/*!
 * fullcalendar v2.6.1
 * docs & license: http://fullcalendar.io/
 * (c) 2015 adam shaw
 */

(function(factory) {
	if (typeof define === 'function' && define.amd) {
		define([ 'jquery', 'moment' ], factory);
	}
	else if (typeof exports === 'object') { // node/commonjs
		module.exports = factory(require('jquery'), require('moment'));
	}
	else {
		factory(jquery, moment);
	}
})(function($, moment) {

;;

var fc = $.fullcalendar = {
	version: "2.6.1",
	internalapiversion: 3
};
var fcviews = fc.views = {};


$.fn.fullcalendar = function(options) {
	var args = array.prototype.slice.call(arguments, 1); // for a possible method call
	var res = this; // what this function will return (this jquery object by default)

	this.each(function(i, _element) { // loop each dom element involved
		var element = $(_element);
		var calendar = element.data('fullcalendar'); // get the existing calendar object (if any)
		var singleres; // the returned value of this single method call

		// a method call
		if (typeof options === 'string') {
			if (calendar && $.isfunction(calendar[options])) {
				singleres = calendar[options].apply(calendar, args);
				if (!i) {
					res = singleres; // record the first method call result
				}
				if (options === 'destroy') { // for the destroy method, must remove calendar object data
					element.removedata('fullcalendar');
				}
			}
		}
		// a new calendar initialization
		else if (!calendar) { // don't initialize twice
			calendar = new calendar(element, options);
			element.data('fullcalendar', calendar);
			calendar.render();
		}
	});
	
	return res;
};


var complexoptions = [ // names of options that are objects whose properties should be combined
	'header',
	'buttontext',
	'buttonicons',
	'themebuttonicons'
];


// merges an array of option objects into a single object
function mergeoptions(optionobjs) {
	return mergeprops(optionobjs, complexoptions);
}


// given options specified for the calendar's constructor, massages any legacy options into a non-legacy form.
// converts view-option-hashes into the view-specific-options format.
function massageoverrides(input) {
	var overrides = { views: input.views || {} }; // the output. ensure a `views` hash
	var subobj;

	// iterate through all option override properties (except `views`)
	$.each(input, function(name, val) {
		if (name != 'views') {

			// could the value be a legacy view-option-hash?
			if (
				$.isplainobject(val) &&
				!/(time|duration|interval)$/i.test(name) && // exclude duration options. might be given as objects
				$.inarray(name, complexoptions) == -1 // complex options aren't allowed to be view-option-hashes
			) {
				subobj = null;

				// iterate through the properties of this possible view-option-hash value
				$.each(val, function(subname, subval) {

					// is the property targeting a view?
					if (/^(month|week|day|default|basic(week|day)?|agenda(week|day)?)$/.test(subname)) {
						if (!overrides.views[subname]) { // ensure the view-target entry exists
							overrides.views[subname] = {};
						}
						overrides.views[subname][name] = subval; // record the value in the `views` object
					}
					else { // a non-view-option-hash property
						if (!subobj) {
							subobj = {};
						}
						subobj[subname] = subval; // accumulate these unrelated values for later
					}
				});

				if (subobj) { // non-view-option-hash properties? transfer them as-is
					overrides[name] = subobj;
				}
			}
			else {
				overrides[name] = val; // transfer normal options as-is
			}
		}
	});

	return overrides;
}

;;

// exports
fc.intersectranges = intersectranges;
fc.applyall = applyall;
fc.debounce = debounce;
fc.isint = isint;
fc.htmlescape = htmlescape;
fc.csstostr = csstostr;
fc.proxy = proxy;
fc.capitalisefirstletter = capitalisefirstletter;


/* fullcalendar-specific dom utilities
----------------------------------------------------------------------------------------------------------------------*/


// given the scrollbar widths of some other container, create borders/margins on rowels in order to match the left
// and right space that was offset by the scrollbars. a 1-pixel border first, then margin beyond that.
function compensatescroll(rowels, scrollbarwidths) {
	if (scrollbarwidths.left) {
		rowels.css({
			'border-left-width': 1,
			'margin-left': scrollbarwidths.left - 1
		});
	}
	if (scrollbarwidths.right) {
		rowels.css({
			'border-right-width': 1,
			'margin-right': scrollbarwidths.right - 1
		});
	}
}


// undoes compensatescroll and restores all borders/margins
function uncompensatescroll(rowels) {
	rowels.css({
		'margin-left': '',
		'margin-right': '',
		'border-left-width': '',
		'border-right-width': ''
	});
}


// make the mouse cursor express that an event is not allowed in the current area
function disablecursor() {
	$('body').addclass('fc-not-allowed');
}


// returns the mouse cursor to its original look
function enablecursor() {
	$('body').removeclass('fc-not-allowed');
}


// given a total available height to fill, have `els` (essentially child rows) expand to accomodate.
// by default, all elements that are shorter than the recommended height are expanded uniformly, not considering
// any other els that are already too tall. if `shouldredistribute` is on, it considers these tall rows and 
// reduces the available height.
function distributeheight(els, availableheight, shouldredistribute) {

	// *flooring note*: we floor in certain places because zoom can give inaccurate floating-point dimensions,
	// and it is better to be shorter than taller, to avoid creating unnecessary scrollbars.

	var minoffset1 = math.floor(availableheight / els.length); // for non-last element
	var minoffset2 = math.floor(availableheight - minoffset1 * (els.length - 1)); // for last element *flooring note*
	var flexels = []; // elements that are allowed to expand. array of dom nodes
	var flexoffsets = []; // amount of vertical space it takes up
	var flexheights = []; // actual css height
	var usedheight = 0;

	undistributeheight(els); // give all elements their natural height

	// find elements that are below the recommended height (expandable).
	// important to query for heights in a single first pass (to avoid reflow oscillation).
	els.each(function(i, el) {
		var minoffset = i === els.length - 1 ? minoffset2 : minoffset1;
		var naturaloffset = $(el).outerheight(true);

		if (naturaloffset < minoffset) {
			flexels.push(el);
			flexoffsets.push(naturaloffset);
			flexheights.push($(el).height());
		}
		else {
			// this element stretches past recommended height (non-expandable). mark the space as occupied.
			usedheight += naturaloffset;
		}
	});

	// readjust the recommended height to only consider the height available to non-maxed-out rows.
	if (shouldredistribute) {
		availableheight -= usedheight;
		minoffset1 = math.floor(availableheight / flexels.length);
		minoffset2 = math.floor(availableheight - minoffset1 * (flexels.length - 1)); // *flooring note*
	}

	// assign heights to all expandable elements
	$(flexels).each(function(i, el) {
		var minoffset = i === flexels.length - 1 ? minoffset2 : minoffset1;
		var naturaloffset = flexoffsets[i];
		var naturalheight = flexheights[i];
		var newheight = minoffset - (naturaloffset - naturalheight); // subtract the margin/padding

		if (naturaloffset < minoffset) { // we check this again because redistribution might have changed things
			$(el).height(newheight);
		}
	});
}


// undoes distrubuteheight, restoring all els to their natural height
function undistributeheight(els) {
	els.height('');
}


// given `els`, a jquery set of <td> cells, find the cell with the largest natural width and set the widths of all the
// cells to be that width.
// prerequisite: if you want a cell to take up width, it needs to have a single inner element w/ display:inline
function matchcellwidths(els) {
	var maxinnerwidth = 0;

	els.find('> span').each(function(i, innerel) {
		var innerwidth = $(innerel).outerwidth();
		if (innerwidth > maxinnerwidth) {
			maxinnerwidth = innerwidth;
		}
	});

	maxinnerwidth++; // sometimes not accurate of width the text needs to stay on one line. insurance

	els.width(maxinnerwidth);

	return maxinnerwidth;
}


// turns a container element into a scroller if its contents is taller than the allotted height.
// returns true if the element is now a scroller, false otherwise.
// note: this method is best because it takes weird zooming dimensions into account
function setpotentialscroller(containerel, height) {
	containerel.height(height).addclass('fc-scroller');

	// are scrollbars needed?
	if (containerel[0].scrollheight - 1 > containerel[0].clientheight) { // !!! -1 because ie is often off-by-one :(
		return true;
	}

	unsetscroller(containerel); // undo
	return false;
}


// takes an element that might have been a scroller, and turns it back into a normal element.
function unsetscroller(containerel) {
	containerel.height('').removeclass('fc-scroller');
}


/* general dom utilities
----------------------------------------------------------------------------------------------------------------------*/

fc.getouterrect = getouterrect;
fc.getclientrect = getclientrect;
fc.getcontentrect = getcontentrect;
fc.getscrollbarwidths = getscrollbarwidths;


// borrowed from https://github.com/jquery/jquery-ui/blob/1.11.0/ui/core.js#l51
function getscrollparent(el) {
	var position = el.css('position'),
		scrollparent = el.parents().filter(function() {
			var parent = $(this);
			return (/(auto|scroll)/).test(
				parent.css('overflow') + parent.css('overflow-y') + parent.css('overflow-x')
			);
		}).eq(0);

	return position === 'fixed' || !scrollparent.length ? $(el[0].ownerdocument || document) : scrollparent;
}


// queries the outer bounding area of a jquery element.
// returns a rectangle with absolute coordinates: left, right (exclusive), top, bottom (exclusive).
function getouterrect(el) {
	var offset = el.offset();

	return {
		left: offset.left,
		right: offset.left + el.outerwidth(),
		top: offset.top,
		bottom: offset.top + el.outerheight()
	};
}


// queries the area within the margin/border/scrollbars of a jquery element. does not go within the padding.
// returns a rectangle with absolute coordinates: left, right (exclusive), top, bottom (exclusive).
// note: should use clientleft/clienttop, but very unreliable cross-browser.
function getclientrect(el) {
	var offset = el.offset();
	var scrollbarwidths = getscrollbarwidths(el);
	var left = offset.left + getcssfloat(el, 'border-left-width') + scrollbarwidths.left;
	var top = offset.top + getcssfloat(el, 'border-top-width') + scrollbarwidths.top;

	return {
		left: left,
		right: left + el[0].clientwidth, // clientwidth includes padding but not scrollbars
		top: top,
		bottom: top + el[0].clientheight // clientheight includes padding but not scrollbars
	};
}


// queries the area within the margin/border/padding of a jquery element. assumed not to have scrollbars.
// returns a rectangle with absolute coordinates: left, right (exclusive), top, bottom (exclusive).
function getcontentrect(el) {
	var offset = el.offset(); // just outside of border, margin not included
	var left = offset.left + getcssfloat(el, 'border-left-width') + getcssfloat(el, 'padding-left');
	var top = offset.top + getcssfloat(el, 'border-top-width') + getcssfloat(el, 'padding-top');

	return {
		left: left,
		right: left + el.width(),
		top: top,
		bottom: top + el.height()
	};
}


// returns the computed left/right/top/bottom scrollbar widths for the given jquery element.
// note: should use clientleft/clienttop, but very unreliable cross-browser.
function getscrollbarwidths(el) {
	var leftrightwidth = el.innerwidth() - el[0].clientwidth; // the paddings cancel out, leaving the scrollbars
	var widths = {
		left: 0,
		right: 0,
		top: 0,
		bottom: el.innerheight() - el[0].clientheight // the paddings cancel out, leaving the bottom scrollbar
	};

	if (getisleftrtlscrollbars() && el.css('direction') == 'rtl') { // is the scrollbar on the left side?
		widths.left = leftrightwidth;
	}
	else {
		widths.right = leftrightwidth;
	}

	return widths;
}


// logic for determining if, when the element is right-to-left, the scrollbar appears on the left side

var _isleftrtlscrollbars = null;

function getisleftrtlscrollbars() { // responsible for caching the computation
	if (_isleftrtlscrollbars === null) {
		_isleftrtlscrollbars = computeisleftrtlscrollbars();
	}
	return _isleftrtlscrollbars;
}

function computeisleftrtlscrollbars() { // creates an offscreen test element, then removes it
	var el = $('<div><div/></div>')
		.css({
			position: 'absolute',
			top: -1000,
			left: 0,
			border: 0,
			padding: 0,
			overflow: 'scroll',
			direction: 'rtl'
		})
		.appendto('body');
	var innerel = el.children();
	var res = innerel.offset().left > el.offset().left; // is the inner div shifted to accommodate a left scrollbar?
	el.remove();
	return res;
}


// retrieves a jquery element's computed css value as a floating-point number.
// if the queried value is non-numeric (ex: ie can return "medium" for border width), will just return zero.
function getcssfloat(el, prop) {
	return parsefloat(el.css(prop)) || 0;
}


// returns a boolean whether this was a left mouse click and no ctrl key (which means right click on mac)
function isprimarymousebutton(ev) {
	return ev.which == 1 && !ev.ctrlkey;
}


/* geometry
----------------------------------------------------------------------------------------------------------------------*/

fc.intersectrects = intersectrects;

// returns a new rectangle that is the intersection of the two rectangles. if they don't intersect, returns false
function intersectrects(rect1, rect2) {
	var res = {
		left: math.max(rect1.left, rect2.left),
		right: math.min(rect1.right, rect2.right),
		top: math.max(rect1.top, rect2.top),
		bottom: math.min(rect1.bottom, rect2.bottom)
	};

	if (res.left < res.right && res.top < res.bottom) {
		return res;
	}
	return false;
}


// returns a new point that will have been moved to reside within the given rectangle
function constrainpoint(point, rect) {
	return {
		left: math.min(math.max(point.left, rect.left), rect.right),
		top: math.min(math.max(point.top, rect.top), rect.bottom)
	};
}


// returns a point that is the center of the given rectangle
function getrectcenter(rect) {
	return {
		left: (rect.left + rect.right) / 2,
		top: (rect.top + rect.bottom) / 2
	};
}


// subtracts point2's coordinates from point1's coordinates, returning a delta
function diffpoints(point1, point2) {
	return {
		left: point1.left - point2.left,
		top: point1.top - point2.top
	};
}


/* object ordering by field
----------------------------------------------------------------------------------------------------------------------*/

fc.parsefieldspecs = parsefieldspecs;
fc.comparebyfieldspecs = comparebyfieldspecs;
fc.comparebyfieldspec = comparebyfieldspec;
fc.flexiblecompare = flexiblecompare;


function parsefieldspecs(input) {
	var specs = [];
	var tokens = [];
	var i, token;

	if (typeof input === 'string') {
		tokens = input.split(/\s*,\s*/);
	}
	else if (typeof input === 'function') {
		tokens = [ input ];
	}
	else if ($.isarray(input)) {
		tokens = input;
	}

	for (i = 0; i < tokens.length; i++) {
		token = tokens[i];

		if (typeof token === 'string') {
			specs.push(
				token.charat(0) == '-' ?
					{ field: token.substring(1), order: -1 } :
					{ field: token, order: 1 }
			);
		}
		else if (typeof token === 'function') {
			specs.push({ func: token });
		}
	}

	return specs;
}


function comparebyfieldspecs(obj1, obj2, fieldspecs) {
	var i;
	var cmp;

	for (i = 0; i < fieldspecs.length; i++) {
		cmp = comparebyfieldspec(obj1, obj2, fieldspecs[i]);
		if (cmp) {
			return cmp;
		}
	}

	return 0;
}


function comparebyfieldspec(obj1, obj2, fieldspec) {
	if (fieldspec.func) {
		return fieldspec.func(obj1, obj2);
	}
	return flexiblecompare(obj1[fieldspec.field], obj2[fieldspec.field]) *
		(fieldspec.order || 1);
}


function flexiblecompare(a, b) {
	if (!a && !b) {
		return 0;
	}
	if (b == null) {
		return -1;
	}
	if (a == null) {
		return 1;
	}
	if ($.type(a) === 'string' || $.type(b) === 'string') {
		return string(a).localecompare(string(b));
	}
	return a - b;
}


/* fullcalendar-specific misc utilities
----------------------------------------------------------------------------------------------------------------------*/


// computes the intersection of the two ranges. returns undefined if no intersection.
// expects all dates to be normalized to the same timezone beforehand.
// todo: move to date section?
function intersectranges(subjectrange, constraintrange) {
	var subjectstart = subjectrange.start;
	var subjectend = subjectrange.end;
	var constraintstart = constraintrange.start;
	var constraintend = constraintrange.end;
	var segstart, segend;
	var isstart, isend;

	if (subjectend > constraintstart && subjectstart < constraintend) { // in bounds at all?

		if (subjectstart >= constraintstart) {
			segstart = subjectstart.clone();
			isstart = true;
		}
		else {
			segstart = constraintstart.clone();
			isstart =  false;
		}

		if (subjectend <= constraintend) {
			segend = subjectend.clone();
			isend = true;
		}
		else {
			segend = constraintend.clone();
			isend = false;
		}

		return {
			start: segstart,
			end: segend,
			isstart: isstart,
			isend: isend
		};
	}
}


/* date utilities
----------------------------------------------------------------------------------------------------------------------*/

fc.computeintervalunit = computeintervalunit;
fc.dividerangebyduration = dividerangebyduration;
fc.dividedurationbyduration = dividedurationbyduration;
fc.multiplyduration = multiplyduration;
fc.durationhastime = durationhastime;

var dayids = [ 'sun', 'mon', 'tue', 'wed', 'thu', 'fri', 'sat' ];
var intervalunits = [ 'year', 'month', 'week', 'day', 'hour', 'minute', 'second', 'millisecond' ];


// diffs the two moments into a duration where full-days are recorded first, then the remaining time.
// moments will have their timezones normalized.
function diffdaytime(a, b) {
	return moment.duration({
		days: a.clone().striptime().diff(b.clone().striptime(), 'days'),
		ms: a.time() - b.time() // time-of-day from day start. disregards timezone
	});
}


// diffs the two moments via their start-of-day (regardless of timezone). produces whole-day durations.
function diffday(a, b) {
	return moment.duration({
		days: a.clone().striptime().diff(b.clone().striptime(), 'days')
	});
}


// diffs two moments, producing a duration, made of a whole-unit-increment of the given unit. uses rounding.
function diffbyunit(a, b, unit) {
	return moment.duration(
		math.round(a.diff(b, unit, true)), // returnfloat=true
		unit
	);
}


// computes the unit name of the largest whole-unit period of time.
// for example, 48 hours will be "days" whereas 49 hours will be "hours".
// accepts start/end, a range object, or an original duration object.
function computeintervalunit(start, end) {
	var i, unit;
	var val;

	for (i = 0; i < intervalunits.length; i++) {
		unit = intervalunits[i];
		val = computerangeas(unit, start, end);

		if (val >= 1 && isint(val)) {
			break;
		}
	}

	return unit; // will be "milliseconds" if nothing else matches
}


// computes the number of units (like "hours") in the given range.
// range can be a {start,end} object, separate start/end args, or a duration.
// results are based on moment's .as() and .diff() methods, so results can depend on internal handling
// of month-diffing logic (which tends to vary from version to version).
function computerangeas(unit, start, end) {

	if (end != null) { // given start, end
		return end.diff(start, unit, true);
	}
	else if (moment.isduration(start)) { // given duration
		return start.as(unit);
	}
	else { // given { start, end } range object
		return start.end.diff(start.start, unit, true);
	}
}


// intelligently divides a range (specified by a start/end params) by a duration
function dividerangebyduration(start, end, dur) {
	var months;

	if (durationhastime(dur)) {
		return (end - start) / dur;
	}
	months = dur.asmonths();
	if (math.abs(months) >= 1 && isint(months)) {
		return end.diff(start, 'months', true) / months;
	}
	return end.diff(start, 'days', true) / dur.asdays();
}


// intelligently divides one duration by another
function dividedurationbyduration(dur1, dur2) {
	var months1, months2;

	if (durationhastime(dur1) || durationhastime(dur2)) {
		return dur1 / dur2;
	}
	months1 = dur1.asmonths();
	months2 = dur2.asmonths();
	if (
		math.abs(months1) >= 1 && isint(months1) &&
		math.abs(months2) >= 1 && isint(months2)
	) {
		return months1 / months2;
	}
	return dur1.asdays() / dur2.asdays();
}


// intelligently multiplies a duration by a number
function multiplyduration(dur, n) {
	var months;

	if (durationhastime(dur)) {
		return moment.duration(dur * n);
	}
	months = dur.asmonths();
	if (math.abs(months) >= 1 && isint(months)) {
		return moment.duration({ months: months * n });
	}
	return moment.duration({ days: dur.asdays() * n });
}


// returns a boolean about whether the given duration has any time parts (hours/minutes/seconds/ms)
function durationhastime(dur) {
	return boolean(dur.hours() || dur.minutes() || dur.seconds() || dur.milliseconds());
}


function isnativedate(input) {
	return  object.prototype.tostring.call(input) === '[object date]' || input instanceof date;
}


// returns a boolean about whether the given input is a time string, like "06:40:00" or "06:00"
function istimestring(str) {
	return /^\d+\:\d+(?:\:\d+\.?(?:\d{3})?)?$/.test(str);
}


/* logging and debug
----------------------------------------------------------------------------------------------------------------------*/

fc.log = function() {
	var console = window.console;

	if (console && console.log) {
		return console.log.apply(console, arguments);
	}
};

fc.warn = function() {
	var console = window.console;

	if (console && console.warn) {
		return console.warn.apply(console, arguments);
	}
	else {
		return fc.log.apply(fc, arguments);
	}
};


/* general utilities
----------------------------------------------------------------------------------------------------------------------*/

var hasownpropmethod = {}.hasownproperty;


// merges an array of objects into a single object.
// the second argument allows for an array of property names who's object values will be merged together.
function mergeprops(propobjs, complexprops) {
	var dest = {};
	var i, name;
	var complexobjs;
	var j, val;
	var props;

	if (complexprops) {
		for (i = 0; i < complexprops.length; i++) {
			name = complexprops[i];
			complexobjs = [];

			// collect the trailing object values, stopping when a non-object is discovered
			for (j = propobjs.length - 1; j >= 0; j--) {
				val = propobjs[j][name];

				if (typeof val === 'object') {
					complexobjs.unshift(val);
				}
				else if (val !== undefined) {
					dest[name] = val; // if there were no objects, this value will be used
					break;
				}
			}

			// if the trailing values were objects, use the merged value
			if (complexobjs.length) {
				dest[name] = mergeprops(complexobjs);
			}
		}
	}

	// copy values into the destination, going from last to first
	for (i = propobjs.length - 1; i >= 0; i--) {
		props = propobjs[i];

		for (name in props) {
			if (!(name in dest)) { // if already assigned by previous props or complex props, don't reassign
				dest[name] = props[name];
			}
		}
	}

	return dest;
}


// create an object that has the given prototype. just like object.create
function createobject(proto) {
	var f = function() {};
	f.prototype = proto;
	return new f();
}


function copyownprops(src, dest) {
	for (var name in src) {
		if (hasownprop(src, name)) {
			dest[name] = src[name];
		}
	}
}


// copies over certain methods with the same names as object.prototype methods. overcomes an ie<=8 bug:
// https://developer.mozilla.org/en-us/docs/ecmascript_dontenum_attribute#jscript_dontenum_bug
function copynativemethods(src, dest) {
	var names = [ 'constructor', 'tostring', 'valueof' ];
	var i, name;

	for (i = 0; i < names.length; i++) {
		name = names[i];

		if (src[name] !== object.prototype[name]) {
			dest[name] = src[name];
		}
	}
}


function hasownprop(obj, name) {
	return hasownpropmethod.call(obj, name);
}


// is the given value a non-object non-function value?
function isatomic(val) {
	return /undefined|null|boolean|number|string/.test($.type(val));
}


function applyall(functions, thisobj, args) {
	if ($.isfunction(functions)) {
		functions = [ functions ];
	}
	if (functions) {
		var i;
		var ret;
		for (i=0; i<functions.length; i++) {
			ret = functions[i].apply(thisobj, args) || ret;
		}
		return ret;
	}
}


function firstdefined() {
	for (var i=0; i<arguments.length; i++) {
		if (arguments[i] !== undefined) {
			return arguments[i];
		}
	}
}


function htmlescape(s) {
	return (s + '').replace(/&/g, '&amp;')
		.replace(/</g, '&lt;')
		.replace(/>/g, '&gt;')
		.replace(/'/g, '&#039;')
		.replace(/"/g, '&quot;')
		.replace(/\n/g, '<br />');
}


function striphtmlentities(text) {
	return text.replace(/&.*?;/g, '');
}


// given a hash of css properties, returns a string of css.
// uses property names as-is (no camel-case conversion). will not make statements for null/undefined values.
function csstostr(cssprops) {
	var statements = [];

	$.each(cssprops, function(name, val) {
		if (val != null) {
			statements.push(name + ':' + val);
		}
	});

	return statements.join(';');
}


function capitalisefirstletter(str) {
	return str.charat(0).touppercase() + str.slice(1);
}


function comparenumbers(a, b) { // for .sort()
	return a - b;
}


function isint(n) {
	return n % 1 === 0;
}


// returns a method bound to the given object context.
// just like one of the jquery.proxy signatures, but without the undesired behavior of treating the same method with
// different contexts as identical when binding/unbinding events.
function proxy(obj, methodname) {
	var method = obj[methodname];

	return function() {
		return method.apply(obj, arguments);
	};
}


// returns a function, that, as long as it continues to be invoked, will not
// be triggered. the function will be called after it stops being called for
// n milliseconds.
// https://github.com/jashkenas/underscore/blob/1.6.0/underscore.js#l714
function debounce(func, wait) {
	var timeoutid;
	var args;
	var context;
	var timestamp; // of most recent call
	var later = function() {
		var last = +new date() - timestamp;
		if (last < wait && last > 0) {
			timeoutid = settimeout(later, wait - last);
		}
		else {
			timeoutid = null;
			func.apply(context, args);
			if (!timeoutid) {
				context = args = null;
			}
		}
	};

	return function() {
		context = this;
		args = arguments;
		timestamp = +new date();
		if (!timeoutid) {
			timeoutid = settimeout(later, wait);
		}
	};
}

;;

var ambigdateofmonthregex = /^\s*\d{4}-\d\d$/;
var ambigtimeorzoneregex =
	/^\s*\d{4}-(?:(\d\d-\d\d)|(w\d\d$)|(w\d\d-\d)|(\d\d\d))((t| )(\d\d(:\d\d(:\d\d(\.\d+)?)?)?)?)?$/;
var newmomentproto = moment.fn; // where we will attach our new methods
var oldmomentproto = $.extend({}, newmomentproto); // copy of original moment methods
var allowvalueoptimization;
var setutcvalues; // function defined below
var setlocalvalues; // function defined below


// creating
// -------------------------------------------------------------------------------------------------

// creates a new moment, similar to the vanilla moment(...) constructor, but with
// extra features (ambiguous time, enhanced formatting). when given an existing moment,
// it will function as a clone (and retain the zone of the moment). anything else will
// result in a moment in the local zone.
fc.moment = function() {
	return makemoment(arguments);
};

// sames as fc.moment, but forces the resulting moment to be in the utc timezone.
fc.moment.utc = function() {
	var mom = makemoment(arguments, true);

	// force it into utc because makemoment doesn't guarantee it
	// (if given a pre-existing moment for example)
	if (mom.hastime()) { // don't give ambiguously-timed moments a utc zone
		mom.utc();
	}

	return mom;
};

// same as fc.moment, but when given an iso8601 string, the timezone offset is preserved.
// iso8601 strings with no timezone offset will become ambiguously zoned.
fc.moment.parsezone = function() {
	return makemoment(arguments, true, true);
};

// builds an enhanced moment from args. when given an existing moment, it clones. when given a
// native date, or called with no arguments (the current time), the resulting moment will be local.
// anything else needs to be "parsed" (a string or an array), and will be affected by:
//    parseasutc - if there is no zone information, should we parse the input in utc?
//    parsezone - if there is zone information, should we force the zone of the moment?
function makemoment(args, parseasutc, parsezone) {
	var input = args[0];
	var issinglestring = args.length == 1 && typeof input === 'string';
	var isambigtime;
	var isambigzone;
	var ambigmatch;
	var mom;

	if (moment.ismoment(input)) {
		mom = moment.apply(null, args); // clone it
		transferambigs(input, mom); // the ambig flags weren't transfered with the clone
	}
	else if (isnativedate(input) || input === undefined) {
		mom = moment.apply(null, args); // will be local
	}
	else { // "parsing" is required
		isambigtime = false;
		isambigzone = false;

		if (issinglestring) {
			if (ambigdateofmonthregex.test(input)) {
				// accept strings like '2014-05', but convert to the first of the month
				input += '-01';
				args = [ input ]; // for when we pass it on to moment's constructor
				isambigtime = true;
				isambigzone = true;
			}
			else if ((ambigmatch = ambigtimeorzoneregex.exec(input))) {
				isambigtime = !ambigmatch[5]; // no time part?
				isambigzone = true;
			}
		}
		else if ($.isarray(input)) {
			// arrays have no timezone information, so assume ambiguous zone
			isambigzone = true;
		}
		// otherwise, probably a string with a format

		if (parseasutc || isambigtime) {
			mom = moment.utc.apply(moment, args);
		}
		else {
			mom = moment.apply(null, args);
		}

		if (isambigtime) {
			mom._ambigtime = true;
			mom._ambigzone = true; // ambiguous time always means ambiguous zone
		}
		else if (parsezone) { // let's record the inputted zone somehow
			if (isambigzone) {
				mom._ambigzone = true;
			}
			else if (issinglestring) {
				if (mom.utcoffset) {
					mom.utcoffset(input); // if not a valid zone, will assign utc
				}
				else {
					mom.zone(input); // for moment-pre-2.9
				}
			}
		}
	}

	mom._fullcalendar = true; // flag for extended functionality

	return mom;
}


// a clone method that works with the flags related to our enhanced functionality.
// in the future, use moment.momentproperties
newmomentproto.clone = function() {
	var mom = oldmomentproto.clone.apply(this, arguments);

	// these flags weren't transfered with the clone
	transferambigs(this, mom);
	if (this._fullcalendar) {
		mom._fullcalendar = true;
	}

	return mom;
};


// week number
// -------------------------------------------------------------------------------------------------


// returns the week number, considering the locale's custom week number calcuation
// `weeks` is an alias for `week`
newmomentproto.week = newmomentproto.weeks = function(input) {
	var weekcalc = (this._locale || this._lang) // works pre-moment-2.8
		._fullcalendar_weekcalc;

	if (input == null && typeof weekcalc === 'function') { // custom function only works for getter
		return weekcalc(this);
	}
	else if (weekcalc === 'iso') {
		return oldmomentproto.isoweek.apply(this, arguments); // iso getter/setter
	}

	return oldmomentproto.week.apply(this, arguments); // local getter/setter
};


// time-of-day
// -------------------------------------------------------------------------------------------------

// getter
// returns a duration with the hours/minutes/seconds/ms values of the moment.
// if the moment has an ambiguous time, a duration of 00:00 will be returned.
//
// setter
// you can supply a duration, a moment, or a duration-like argument.
// when setting the time, and the moment has an ambiguous time, it then becomes unambiguous.
newmomentproto.time = function(time) {

	// fallback to the original method (if there is one) if this moment wasn't created via fullcalendar.
	// `time` is a generic enough method name where this precaution is necessary to avoid collisions w/ other plugins.
	if (!this._fullcalendar) {
		return oldmomentproto.time.apply(this, arguments);
	}

	if (time == null) { // getter
		return moment.duration({
			hours: this.hours(),
			minutes: this.minutes(),
			seconds: this.seconds(),
			milliseconds: this.milliseconds()
		});
	}
	else { // setter

		this._ambigtime = false; // mark that the moment now has a time

		if (!moment.isduration(time) && !moment.ismoment(time)) {
			time = moment.duration(time);
		}

		// the day value should cause overflow (so 24 hours becomes 00:00:00 of next day).
		// only for duration times, not moment times.
		var dayhours = 0;
		if (moment.isduration(time)) {
			dayhours = math.floor(time.asdays()) * 24;
		}

		// we need to set the individual fields.
		// can't use startof('day') then add duration. in case of dst at start of day.
		return this.hours(dayhours + time.hours())
			.minutes(time.minutes())
			.seconds(time.seconds())
			.milliseconds(time.milliseconds());
	}
};

// converts the moment to utc, stripping out its time-of-day and timezone offset,
// but preserving its ymd. a moment with a stripped time will display no time
// nor timezone offset when .format() is called.
newmomentproto.striptime = function() {
	var a;

	if (!this._ambigtime) {

		// get the values before any conversion happens
		a = this.toarray(); // array of y/m/d/h/m/s/ms

		// todo: use keeplocaltime in the future
		this.utc(); // set the internal utc flag (will clear the ambig flags)
		setutcvalues(this, a.slice(0, 3)); // set the year/month/date. time will be zero

		// mark the time as ambiguous. this needs to happen after the .utc() call, which might call .utcoffset(),
		// which clears all ambig flags. same with setutcvalues with moment-timezone.
		this._ambigtime = true;
		this._ambigzone = true; // if ambiguous time, also ambiguous timezone offset
	}

	return this; // for chaining
};

// returns if the moment has a non-ambiguous time (boolean)
newmomentproto.hastime = function() {
	return !this._ambigtime;
};


// timezone
// -------------------------------------------------------------------------------------------------

// converts the moment to utc, stripping out its timezone offset, but preserving its
// ymd and time-of-day. a moment with a stripped timezone offset will display no
// timezone offset when .format() is called.
// todo: look into moment's keeplocaltime functionality
newmomentproto.stripzone = function() {
	var a, wasambigtime;

	if (!this._ambigzone) {

		// get the values before any conversion happens
		a = this.toarray(); // array of y/m/d/h/m/s/ms
		wasambigtime = this._ambigtime;

		this.utc(); // set the internal utc flag (might clear the ambig flags, depending on moment internals)
		setutcvalues(this, a); // will set the year/month/date/hours/minutes/seconds/ms

		// the above call to .utc()/.utcoffset() unfortunately might clear the ambig flags, so restore
		this._ambigtime = wasambigtime || false;

		// mark the zone as ambiguous. this needs to happen after the .utc() call, which might call .utcoffset(),
		// which clears the ambig flags. same with setutcvalues with moment-timezone.
		this._ambigzone = true;
	}

	return this; // for chaining
};

// returns of the moment has a non-ambiguous timezone offset (boolean)
newmomentproto.haszone = function() {
	return !this._ambigzone;
};


// this method implicitly marks a zone
newmomentproto.local = function() {
	var a = this.toarray(); // year,month,date,hours,minutes,seconds,ms as an array
	var wasambigzone = this._ambigzone;

	oldmomentproto.local.apply(this, arguments);

	// ensure non-ambiguous
	// this probably already happened via local() -> utcoffset(), but don't rely on moment's internals
	this._ambigtime = false;
	this._ambigzone = false;

	if (wasambigzone) {
		// if the moment was ambiguously zoned, the date fields were stored as utc.
		// we want to preserve these, but in local time.
		// todo: look into moment's keeplocaltime functionality
		setlocalvalues(this, a);
	}

	return this; // for chaining
};


// implicitly marks a zone
newmomentproto.utc = function() {
	oldmomentproto.utc.apply(this, arguments);

	// ensure non-ambiguous
	// this probably already happened via utc() -> utcoffset(), but don't rely on moment's internals
	this._ambigtime = false;
	this._ambigzone = false;

	return this;
};


// methods for arbitrarily manipulating timezone offset.
// should clear time/zone ambiguity when called.
$.each([
	'zone', // only in moment-pre-2.9. deprecated afterwards
	'utcoffset'
], function(i, name) {
	if (oldmomentproto[name]) { // original method exists?

		// this method implicitly marks a zone (will probably get called upon .utc() and .local())
		newmomentproto[name] = function(tzo) {

			if (tzo != null) { // setter
				// these assignments needs to happen before the original zone method is called.
				// i forget why, something to do with a browser crash.
				this._ambigtime = false;
				this._ambigzone = false;
			}

			return oldmomentproto[name].apply(this, arguments);
		};
	}
});


// formatting
// -------------------------------------------------------------------------------------------------

newmomentproto.format = function() {
	if (this._fullcalendar && arguments[0]) { // an enhanced moment? and a format string provided?
		return formatdate(this, arguments[0]); // our extended formatting
	}
	if (this._ambigtime) {
		return oldmomentformat(this, 'yyyy-mm-dd');
	}
	if (this._ambigzone) {
		return oldmomentformat(this, 'yyyy-mm-dd[t]hh:mm:ss');
	}
	return oldmomentproto.format.apply(this, arguments);
};

newmomentproto.toisostring = function() {
	if (this._ambigtime) {
		return oldmomentformat(this, 'yyyy-mm-dd');
	}
	if (this._ambigzone) {
		return oldmomentformat(this, 'yyyy-mm-dd[t]hh:mm:ss');
	}
	return oldmomentproto.toisostring.apply(this, arguments);
};


// querying
// -------------------------------------------------------------------------------------------------

// is the moment within the specified range? `end` is exclusive.
// fyi, this method is not a standard moment method, so always do our enhanced logic.
newmomentproto.iswithin = function(start, end) {
	var a = commonlyambiguate([ this, start, end ]);
	return a[0] >= a[1] && a[0] < a[2];
};

// when issame is called with units, timezone ambiguity is normalized before the comparison happens.
// if no units specified, the two moments must be identically the same, with matching ambig flags.
newmomentproto.issame = function(input, units) {
	var a;

	// only do custom logic if this is an enhanced moment
	if (!this._fullcalendar) {
		return oldmomentproto.issame.apply(this, arguments);
	}

	if (units) {
		a = commonlyambiguate([ this, input ], true); // normalize timezones but don't erase times
		return oldmomentproto.issame.call(a[0], a[1], units);
	}
	else {
		input = fc.moment.parsezone(input); // normalize input
		return oldmomentproto.issame.call(this, input) &&
			boolean(this._ambigtime) === boolean(input._ambigtime) &&
			boolean(this._ambigzone) === boolean(input._ambigzone);
	}
};

// make these query methods work with ambiguous moments
$.each([
	'isbefore',
	'isafter'
], function(i, methodname) {
	newmomentproto[methodname] = function(input, units) {
		var a;

		// only do custom logic if this is an enhanced moment
		if (!this._fullcalendar) {
			return oldmomentproto[methodname].apply(this, arguments);
		}

		a = commonlyambiguate([ this, input ]);
		return oldmomentproto[methodname].call(a[0], a[1], units);
	};
});


// misc internals
// -------------------------------------------------------------------------------------------------

// given an array of moment-like inputs, return a parallel array w/ moments similarly ambiguated.
// for example, of one moment has ambig time, but not others, all moments will have their time stripped.
// set `preservetime` to `true` to keep times, but only normalize zone ambiguity.
// returns the original moments if no modifications are necessary.
function commonlyambiguate(inputs, preservetime) {
	var anyambigtime = false;
	var anyambigzone = false;
	var len = inputs.length;
	var moms = [];
	var i, mom;

	// parse inputs into real moments and query their ambig flags
	for (i = 0; i < len; i++) {
		mom = inputs[i];
		if (!moment.ismoment(mom)) {
			mom = fc.moment.parsezone(mom);
		}
		anyambigtime = anyambigtime || mom._ambigtime;
		anyambigzone = anyambigzone || mom._ambigzone;
		moms.push(mom);
	}

	// strip each moment down to lowest common ambiguity
	// use clones to avoid modifying the original moments
	for (i = 0; i < len; i++) {
		mom = moms[i];
		if (!preservetime && anyambigtime && !mom._ambigtime) {
			moms[i] = mom.clone().striptime();
		}
		else if (anyambigzone && !mom._ambigzone) {
			moms[i] = mom.clone().stripzone();
		}
	}

	return moms;
}

// transfers all the flags related to ambiguous time/zone from the `src` moment to the `dest` moment
// todo: look into moment.momentproperties for this.
function transferambigs(src, dest) {
	if (src._ambigtime) {
		dest._ambigtime = true;
	}
	else if (dest._ambigtime) {
		dest._ambigtime = false;
	}

	if (src._ambigzone) {
		dest._ambigzone = true;
	}
	else if (dest._ambigzone) {
		dest._ambigzone = false;
	}
}


// sets the year/month/date/etc values of the moment from the given array.
// inefficient because it calls each individual setter.
function setmomentvalues(mom, a) {
	mom.year(a[0] || 0)
		.month(a[1] || 0)
		.date(a[2] || 0)
		.hours(a[3] || 0)
		.minutes(a[4] || 0)
		.seconds(a[5] || 0)
		.milliseconds(a[6] || 0);
}

// can we set the moment's internal date directly?
allowvalueoptimization = '_d' in moment() && 'updateoffset' in moment;

// utility function. accepts a moment and an array of the utc year/month/date/etc values to set.
// assumes the given moment is already in utc mode.
setutcvalues = allowvalueoptimization ? function(mom, a) {
	// simlate what moment's accessors do
	mom._d.settime(date.utc.apply(date, a));
	moment.updateoffset(mom, false); // keeptime=false
} : setmomentvalues;

// utility function. accepts a moment and an array of the local year/month/date/etc values to set.
// assumes the given moment is already in local mode.
setlocalvalues = allowvalueoptimization ? function(mom, a) {
	// simlate what moment's accessors do
	mom._d.settime(+new date( // fyi, there is now way to apply an array of args to a constructor
		a[0] || 0,
		a[1] || 0,
		a[2] || 0,
		a[3] || 0,
		a[4] || 0,
		a[5] || 0,
		a[6] || 0
	));
	moment.updateoffset(mom, false); // keeptime=false
} : setmomentvalues;

;;

// single date formatting
// -------------------------------------------------------------------------------------------------


// call this if you want moment's original format method to be used
function oldmomentformat(mom, formatstr) {
	return oldmomentproto.format.call(mom, formatstr); // oldmomentproto defined in moment-ext.js
}


// formats `date` with a moment formatting string, but allow our non-zero areas and
// additional token.
function formatdate(date, formatstr) {
	return formatdatewithchunks(date, getformatstringchunks(formatstr));
}


function formatdatewithchunks(date, chunks) {
	var s = '';
	var i;

	for (i=0; i<chunks.length; i++) {
		s += formatdatewithchunk(date, chunks[i]);
	}

	return s;
}


// addition formatting tokens we want recognized
var tokenoverrides = {
	t: function(date) { // "a" or "p"
		return oldmomentformat(date, 'a').charat(0);
	},
	t: function(date) { // "a" or "p"
		return oldmomentformat(date, 'a').charat(0);
	}
};


function formatdatewithchunk(date, chunk) {
	var token;
	var maybestr;

	if (typeof chunk === 'string') { // a literal string
		return chunk;
	}
	else if ((token = chunk.token)) { // a token, like "yyyy"
		if (tokenoverrides[token]) {
			return tokenoverrides[token](date); // use our custom token
		}
		return oldmomentformat(date, token);
	}
	else if (chunk.maybe) { // a grouping of other chunks that must be non-zero
		maybestr = formatdatewithchunks(date, chunk.maybe);
		if (maybestr.match(/[1-9]/)) {
			return maybestr;
		}
	}

	return '';
}


// date range formatting
// -------------------------------------------------------------------------------------------------
// todo: make it work with timezone offset

// using a formatting string meant for a single date, generate a range string, like
// "sep 2 - 9 2013", that intelligently inserts a separator where the dates differ.
// if the dates are the same as far as the format string is concerned, just return a single
// rendering of one date, without any separator.
function formatrange(date1, date2, formatstr, separator, isrtl) {
	var localedata;

	date1 = fc.moment.parsezone(date1);
	date2 = fc.moment.parsezone(date2);

	localedata = (date1.localedata || date1.lang).call(date1); // works with moment-pre-2.8

	// expand localized format strings, like "ll" -> "mmmm d yyyy"
	formatstr = localedata.longdateformat(formatstr) || formatstr;
	// btw, this is not important for `formatdate` because it is impossible to put custom tokens
	// or non-zero areas in moment's localized format strings.

	separator = separator || ' - ';

	return formatrangewithchunks(
		date1,
		date2,
		getformatstringchunks(formatstr),
		separator,
		isrtl
	);
}
fc.formatrange = formatrange; // expose


function formatrangewithchunks(date1, date2, chunks, separator, isrtl) {
	var unzoneddate1 = date1.clone().stripzone(); // for formatsimilarchunk
	var unzoneddate2 = date2.clone().stripzone(); // "
	var chunkstr; // the rendering of the chunk
	var lefti;
	var leftstr = '';
	var righti;
	var rightstr = '';
	var middlei;
	var middlestr1 = '';
	var middlestr2 = '';
	var middlestr = '';

	// start at the leftmost side of the formatting string and continue until you hit a token
	// that is not the same between dates.
	for (lefti=0; lefti<chunks.length; lefti++) {
		chunkstr = formatsimilarchunk(date1, date2, unzoneddate1, unzoneddate2, chunks[lefti]);
		if (chunkstr === false) {
			break;
		}
		leftstr += chunkstr;
	}

	// similarly, start at the rightmost side of the formatting string and move left
	for (righti=chunks.length-1; righti>lefti; righti--) {
		chunkstr = formatsimilarchunk(date1, date2, unzoneddate1, unzoneddate2,  chunks[righti]);
		if (chunkstr === false) {
			break;
		}
		rightstr = chunkstr + rightstr;
	}

	// the area in the middle is different for both of the dates.
	// collect them distinctly so we can jam them together later.
	for (middlei=lefti; middlei<=righti; middlei++) {
		middlestr1 += formatdatewithchunk(date1, chunks[middlei]);
		middlestr2 += formatdatewithchunk(date2, chunks[middlei]);
	}

	if (middlestr1 || middlestr2) {
		if (isrtl) {
			middlestr = middlestr2 + separator + middlestr1;
		}
		else {
			middlestr = middlestr1 + separator + middlestr2;
		}
	}

	return leftstr + middlestr + rightstr;
}


var similarunitmap = {
	y: 'year',
	m: 'month',
	d: 'day', // day of month
	d: 'day', // day of week
	// prevents a separator between anything time-related...
	a: 'second', // am/pm
	a: 'second', // am/pm
	t: 'second', // a/p
	t: 'second', // a/p
	h: 'second', // hour (24)
	h: 'second', // hour (12)
	m: 'second', // minute
	s: 'second' // second
};
// todo: week maybe?


// given a formatting chunk, and given that both dates are similar in the regard the
// formatting chunk is concerned, format date1 against `chunk`. otherwise, return `false`.
function formatsimilarchunk(date1, date2, unzoneddate1, unzoneddate2, chunk) {
	var token;
	var unit;

	if (typeof chunk === 'string') { // a literal string
		return chunk;
	}
	else if ((token = chunk.token)) {
		unit = similarunitmap[token.charat(0)];

		// are the dates the same for this unit of measurement?
		// use the unzoned dates for this calculation because unreliable when near dst (bug #2396)
		if (unit && unzoneddate1.issame(unzoneddate2, unit)) {
			return oldmomentformat(date1, token); // would be the same if we used `date2`
			// btw, don't support custom tokens
		}
	}

	return false; // the chunk is not the same for the two dates
	// btw, don't support splitting on non-zero areas
}


// chunking utils
// -------------------------------------------------------------------------------------------------


var formatstringchunkcache = {};


function getformatstringchunks(formatstr) {
	if (formatstr in formatstringchunkcache) {
		return formatstringchunkcache[formatstr];
	}
	return (formatstringchunkcache[formatstr] = chunkformatstring(formatstr));
}


// break the formatting string into an array of chunks
function chunkformatstring(formatstr) {
	var chunks = [];
	var chunker = /\[([^\]]*)\]|\(([^\)]*)\)|(lts|lt|(\w)\4*o?)|([^\w\[\(]+)/g; // todo: more descrimination
	var match;

	while ((match = chunker.exec(formatstr))) {
		if (match[1]) { // a literal string inside [ ... ]
			chunks.push(match[1]);
		}
		else if (match[2]) { // non-zero formatting inside ( ... )
			chunks.push({ maybe: chunkformatstring(match[2]) });
		}
		else if (match[3]) { // a formatting token
			chunks.push({ token: match[3] });
		}
		else if (match[5]) { // an unenclosed literal string
			chunks.push(match[5]);
		}
	}

	return chunks;
}

;;

fc.class = class; // export

// class that all other classes will inherit from
function class() { }


// called on a class to create a subclass.
// last argument contains instance methods. any argument before the last are considered mixins.
class.extend = function() {
	var len = arguments.length;
	var i;
	var members;

	for (i = 0; i < len; i++) {
		members = arguments[i];
		if (i < len - 1) { // not the last argument?
			mixintoclass(this, members);
		}
	}

	return extendclass(this, members || {}); // members will be undefined if no arguments
};


// adds new member variables/methods to the class's prototype.
// can be called with another class, or a plain object hash containing new members.
class.mixin = function(members) {
	mixintoclass(this, members);
};


function extendclass(superclass, members) {
	var subclass;

	// ensure a constructor for the subclass, forwarding all arguments to the super-constructor if it doesn't exist
	if (hasownprop(members, 'constructor')) {
		subclass = members.constructor;
	}
	if (typeof subclass !== 'function') {
		subclass = members.constructor = function() {
			superclass.apply(this, arguments);
		};
	}

	// build the base prototype for the subclass, which is an new object chained to the superclass's prototype
	subclass.prototype = createobject(superclass.prototype);

	// copy each member variable/method onto the the subclass's prototype
	copyownprops(members, subclass.prototype);
	copynativemethods(members, subclass.prototype); // hack for ie8

	// copy over all class variables/methods to the subclass, such as `extend` and `mixin`
	copyownprops(superclass, subclass);

	return subclass;
}


function mixintoclass(theclass, members) {
	copyownprops(members.prototype || members, theclass.prototype); // todo: copynativemethods?
}
;;

var emitter = fc.emitter = class.extend({

	callbackhash: null,


	on: function(name, callback) {
		this.getcallbacks(name).add(callback);
		return this; // for chaining
	},


	off: function(name, callback) {
		this.getcallbacks(name).remove(callback);
		return this; // for chaining
	},


	trigger: function(name) { // args...
		var args = array.prototype.slice.call(arguments, 1);

		this.triggerwith(name, this, args);

		return this; // for chaining
	},


	triggerwith: function(name, context, args) {
		var callbacks = this.getcallbacks(name);

		callbacks.firewith(context, args);

		return this; // for chaining
	},


	getcallbacks: function(name) {
		var callbacks;

		if (!this.callbackhash) {
			this.callbackhash = {};
		}

		callbacks = this.callbackhash[name];
		if (!callbacks) {
			callbacks = this.callbackhash[name] = $.callbacks();
		}

		return callbacks;
	}

});
;;

/* a rectangular panel that is absolutely positioned over other content
------------------------------------------------------------------------------------------------------------------------
options:
	- classname (string)
	- content (html string or jquery element set)
	- parentel
	- top
	- left
	- right (the x coord of where the right edge should be. not a "css" right)
	- autohide (boolean)
	- show (callback)
	- hide (callback)
*/

var popover = class.extend({

	ishidden: true,
	options: null,
	el: null, // the container element for the popover. generated by this object
	documentmousedownproxy: null, // document mousedown handler bound to `this`
	margin: 10, // the space required between the popover and the edges of the scroll container


	constructor: function(options) {
		this.options = options || {};
	},


	// shows the popover on the specified position. renders it if not already
	show: function() {
		if (this.ishidden) {
			if (!this.el) {
				this.render();
			}
			this.el.show();
			this.position();
			this.ishidden = false;
			this.trigger('show');
		}
	},


	// hides the popover, through css, but does not remove it from the dom
	hide: function() {
		if (!this.ishidden) {
			this.el.hide();
			this.ishidden = true;
			this.trigger('hide');
		}
	},


	// creates `this.el` and renders content inside of it
	render: function() {
		var _this = this;
		var options = this.options;

		this.el = $('<div class="fc-popover"/>')
			.addclass(options.classname || '')
			.css({
				// position initially to the top left to avoid creating scrollbars
				top: 0,
				left: 0
			})
			.append(options.content)
			.appendto(options.parentel);

		// when a click happens on anything inside with a 'fc-close' classname, hide the popover
		this.el.on('click', '.fc-close', function() {
			_this.hide();
		});

		if (options.autohide) {
			$(document).on('mousedown', this.documentmousedownproxy = proxy(this, 'documentmousedown'));
		}
	},


	// triggered when the user clicks *anywhere* in the document, for the autohide feature
	documentmousedown: function(ev) {
		// only hide the popover if the click happened outside the popover
		if (this.el && !$(ev.target).closest(this.el).length) {
			this.hide();
		}
	},


	// hides and unregisters any handlers
	removeelement: function() {
		this.hide();

		if (this.el) {
			this.el.remove();
			this.el = null;
		}

		$(document).off('mousedown', this.documentmousedownproxy);
	},


	// positions the popover optimally, using the top/left/right options
	position: function() {
		var options = this.options;
		var origin = this.el.offsetparent().offset();
		var width = this.el.outerwidth();
		var height = this.el.outerheight();
		var windowel = $(window);
		var viewportel = getscrollparent(this.el);
		var viewporttop;
		var viewportleft;
		var viewportoffset;
		var top; // the "position" (not "offset") values for the popover
		var left; //

		// compute top and left
		top = options.top || 0;
		if (options.left !== undefined) {
			left = options.left;
		}
		else if (options.right !== undefined) {
			left = options.right - width; // derive the left value from the right value
		}
		else {
			left = 0;
		}

		if (viewportel.is(window) || viewportel.is(document)) { // normalize getscrollparent's result
			viewportel = windowel;
			viewporttop = 0; // the window is always at the top left
			viewportleft = 0; // (and .offset() won't work if called here)
		}
		else {
			viewportoffset = viewportel.offset();
			viewporttop = viewportoffset.top;
			viewportleft = viewportoffset.left;
		}

		// if the window is scrolled, it causes the visible area to be further down
		viewporttop += windowel.scrolltop();
		viewportleft += windowel.scrollleft();

		// constrain to the view port. if constrained by two edges, give precedence to top/left
		if (options.viewportconstrain !== false) {
			top = math.min(top, viewporttop + viewportel.outerheight() - height - this.margin);
			top = math.max(top, viewporttop + this.margin);
			left = math.min(left, viewportleft + viewportel.outerwidth() - width - this.margin);
			left = math.max(left, viewportleft + this.margin);
		}

		this.el.css({
			top: top - origin.top,
			left: left - origin.left
		});
	},


	// triggers a callback. calls a function in the option hash of the same name.
	// arguments beyond the first `name` are forwarded on.
	// todo: better code reuse for this. repeat code
	trigger: function(name) {
		if (this.options[name]) {
			this.options[name].apply(this, array.prototype.slice.call(arguments, 1));
		}
	}

});

;;

/*
a cache for the left/right/top/bottom/width/height values for one or more elements.
works with both offset (from topleft document) and position (from offsetparent).

options:
- els
- ishorizontal
- isvertical
*/
var coordcache = fc.coordcache = class.extend({

	els: null, // jquery set (assumed to be siblings)
	forcedoffsetparentel: null, // options can override the natural offsetparent
	origin: null, // {left,top} position of offsetparent of els
	boundingrect: null, // constrain cordinates to this rectangle. {left,right,top,bottom} or null
	ishorizontal: false, // whether to query for left/right/width
	isvertical: false, // whether to query for top/bottom/height

	// arrays of coordinates (offsets from topleft of document)
	lefts: null,
	rights: null,
	tops: null,
	bottoms: null,


	constructor: function(options) {
		this.els = $(options.els);
		this.ishorizontal = options.ishorizontal;
		this.isvertical = options.isvertical;
		this.forcedoffsetparentel = options.offsetparent ? $(options.offsetparent) : null;
	},


	// queries the els for coordinates and stores them.
	// call this method before using and of the get* methods below.
	build: function() {
		var offsetparentel = this.forcedoffsetparentel || this.els.eq(0).offsetparent();

		this.origin = offsetparentel.offset();
		this.boundingrect = this.queryboundingrect();

		if (this.ishorizontal) {
			this.buildelhorizontals();
		}
		if (this.isvertical) {
			this.buildelverticals();
		}
	},


	// destroys all internal data about coordinates, freeing memory
	clear: function() {
		this.origin = null;
		this.boundingrect = null;
		this.lefts = null;
		this.rights = null;
		this.tops = null;
		this.bottoms = null;
	},


	// when called, if coord caches aren't built, builds them
	ensurebuilt: function() {
		if (!this.origin) {
			this.build();
		}
	},


	// compute and return what the elements' bounding rectangle is, from the user's perspective.
	// right now, only returns a rectangle if constrained by an overflow:scroll element.
	queryboundingrect: function() {
		var scrollparentel = getscrollparent(this.els.eq(0));

		if (!scrollparentel.is(document)) {
			return getclientrect(scrollparentel);
		}
	},


	// populates the left/right internal coordinate arrays
	buildelhorizontals: function() {
		var lefts = [];
		var rights = [];

		this.els.each(function(i, node) {
			var el = $(node);
			var left = el.offset().left;
			var width = el.outerwidth();

			lefts.push(left);
			rights.push(left + width);
		});

		this.lefts = lefts;
		this.rights = rights;
	},


	// populates the top/bottom internal coordinate arrays
	buildelverticals: function() {
		var tops = [];
		var bottoms = [];

		this.els.each(function(i, node) {
			var el = $(node);
			var top = el.offset().top;
			var height = el.outerheight();

			tops.push(top);
			bottoms.push(top + height);
		});

		this.tops = tops;
		this.bottoms = bottoms;
	},


	// given a left offset (from document left), returns the index of the el that it horizontally intersects.
	// if no intersection is made, or outside of the boundingrect, returns undefined.
	gethorizontalindex: function(leftoffset) {
		this.ensurebuilt();

		var boundingrect = this.boundingrect;
		var lefts = this.lefts;
		var rights = this.rights;
		var len = lefts.length;
		var i;

		if (!boundingrect || (leftoffset >= boundingrect.left && leftoffset < boundingrect.right)) {
			for (i = 0; i < len; i++) {
				if (leftoffset >= lefts[i] && leftoffset < rights[i]) {
					return i;
				}
			}
		}
	},


	// given a top offset (from document top), returns the index of the el that it vertically intersects.
	// if no intersection is made, or outside of the boundingrect, returns undefined.
	getverticalindex: function(topoffset) {
		this.ensurebuilt();

		var boundingrect = this.boundingrect;
		var tops = this.tops;
		var bottoms = this.bottoms;
		var len = tops.length;
		var i;

		if (!boundingrect || (topoffset >= boundingrect.top && topoffset < boundingrect.bottom)) {
			for (i = 0; i < len; i++) {
				if (topoffset >= tops[i] && topoffset < bottoms[i]) {
					return i;
				}
			}
		}
	},


	// gets the left offset (from document left) of the element at the given index
	getleftoffset: function(leftindex) {
		this.ensurebuilt();
		return this.lefts[leftindex];
	},


	// gets the left position (from offsetparent left) of the element at the given index
	getleftposition: function(leftindex) {
		this.ensurebuilt();
		return this.lefts[leftindex] - this.origin.left;
	},


	// gets the right offset (from document left) of the element at the given index.
	// this value is not relative to the document's right edge, like the css concept of "right" would be.
	getrightoffset: function(leftindex) {
		this.ensurebuilt();
		return this.rights[leftindex];
	},


	// gets the right position (from offsetparent left) of the element at the given index.
	// this value is not relative to the offsetparent's right edge, like the css concept of "right" would be.
	getrightposition: function(leftindex) {
		this.ensurebuilt();
		return this.rights[leftindex] - this.origin.left;
	},


	// gets the width of the element at the given index
	getwidth: function(leftindex) {
		this.ensurebuilt();
		return this.rights[leftindex] - this.lefts[leftindex];
	},


	// gets the top offset (from document top) of the element at the given index
	gettopoffset: function(topindex) {
		this.ensurebuilt();
		return this.tops[topindex];
	},


	// gets the top position (from offsetparent top) of the element at the given position
	gettopposition: function(topindex) {
		this.ensurebuilt();
		return this.tops[topindex] - this.origin.top;
	},

	// gets the bottom offset (from the document top) of the element at the given index.
	// this value is not relative to the offsetparent's bottom edge, like the css concept of "bottom" would be.
	getbottomoffset: function(topindex) {
		this.ensurebuilt();
		return this.bottoms[topindex];
	},


	// gets the bottom position (from the offsetparent top) of the element at the given index.
	// this value is not relative to the offsetparent's bottom edge, like the css concept of "bottom" would be.
	getbottomposition: function(topindex) {
		this.ensurebuilt();
		return this.bottoms[topindex] - this.origin.top;
	},


	// gets the height of the element at the given index
	getheight: function(topindex) {
		this.ensurebuilt();
		return this.bottoms[topindex] - this.tops[topindex];
	}

});

;;

/* tracks a drag's mouse movement, firing various handlers
----------------------------------------------------------------------------------------------------------------------*/
// todo: use emitter

var draglistener = fc.draglistener = class.extend({

	options: null,

	islistening: false,
	isdragging: false,

	// coordinates of the initial mousedown
	originx: null,
	originy: null,

	// handler attached to the document, bound to the draglistener's `this`
	mousemoveproxy: null,
	mouseupproxy: null,

	// for ie8 bug-fighting behavior, for now
	subjectel: null, // the element being draged. optional
	subjecthref: null,

	scrollel: null,
	scrollbounds: null, // { top, bottom, left, right }
	scrolltopvel: null, // pixels per second
	scrollleftvel: null, // pixels per second
	scrollintervalid: null, // id of settimeout for scrolling animation loop
	scrollhandlerproxy: null, // this-scoped function for handling when scrollel is scrolled

	scrollsensitivity: 30, // pixels from edge for scrolling to start
	scrollspeed: 200, // pixels per second, at maximum speed
	scrollintervalms: 50, // millisecond wait between scroll increment


	constructor: function(options) {
		options = options || {};
		this.options = options;
		this.subjectel = options.subjectel;
	},


	// call this when the user does a mousedown. will probably lead to startlistening
	mousedown: function(ev) {
		if (isprimarymousebutton(ev)) {

			ev.preventdefault(); // prevents native selection in most browsers

			this.startlistening(ev);

			// start the drag immediately if there is no minimum distance for a drag start
			if (!this.options.distance) {
				this.startdrag(ev);
			}
		}
	},


	// call this to start tracking mouse movements
	startlistening: function(ev) {
		var scrollparent;

		if (!this.islistening) {

			// grab scroll container and attach handler
			if (ev && this.options.scroll) {
				scrollparent = getscrollparent($(ev.target));
				if (!scrollparent.is(window) && !scrollparent.is(document)) {
					this.scrollel = scrollparent;

					// scope to `this`, and use `debounce` to make sure rapid calls don't happen
					this.scrollhandlerproxy = debounce(proxy(this, 'scrollhandler'), 100);
					this.scrollel.on('scroll', this.scrollhandlerproxy);
				}
			}

			$(document)
				.on('mousemove', this.mousemoveproxy = proxy(this, 'mousemove'))
				.on('mouseup', this.mouseupproxy = proxy(this, 'mouseup'))
				.on('selectstart', this.preventdefault); // prevents native selection in ie<=8

			if (ev) {
				this.originx = ev.pagex;
				this.originy = ev.pagey;
			}
			else {
				// if no starting information was given, origin will be the topleft corner of the screen.
				// if so, dx/dy in the future will be the absolute coordinates.
				this.originx = 0;
				this.originy = 0;
			}

			this.islistening = true;
			this.listenstart(ev);
		}
	},


	// called when drag listening has started (but a real drag has not necessarily began)
	listenstart: function(ev) {
		this.trigger('listenstart', ev);
	},


	// called when the user moves the mouse
	mousemove: function(ev) {
		var dx = ev.pagex - this.originx;
		var dy = ev.pagey - this.originy;
		var mindistance;
		var distancesq; // current distance from the origin, squared

		if (!this.isdragging) { // if not already dragging...
			// then start the drag if the minimum distance criteria is met
			mindistance = this.options.distance || 1;
			distancesq = dx * dx + dy * dy;
			if (distancesq >= mindistance * mindistance) { // use pythagorean theorem
				this.startdrag(ev);
			}
		}

		if (this.isdragging) {
			this.drag(dx, dy, ev); // report a drag, even if this mousemove initiated the drag
		}
	},


	// call this to initiate a legitimate drag.
	// this function is called internally from this class, but can also be called explicitly from outside
	startdrag: function(ev) {

		if (!this.islistening) { // startdrag must have manually initiated
			this.startlistening();
		}

		if (!this.isdragging) {
			this.isdragging = true;
			this.dragstart(ev);
		}
	},


	// called when the actual drag has started (went beyond mindistance)
	dragstart: function(ev) {
		var subjectel = this.subjectel;

		this.trigger('dragstart', ev);

		// remove a mousedown'd <a>'s href so it is not visited (ie8 bug)
		if ((this.subjecthref = subjectel ? subjectel.attr('href') : null)) {
			subjectel.removeattr('href');
		}
	},


	// called while the mouse is being moved and when we know a legitimate drag is taking place
	drag: function(dx, dy, ev) {
		this.trigger('drag', dx, dy, ev);
		this.updatescroll(ev); // will possibly cause scrolling
	},


	// called when the user does a mouseup
	mouseup: function(ev) {
		this.stoplistening(ev);
	},


	// called when the drag is over. will not cause listening to stop however.
	// a concluding 'cellout' event will not be triggered.
	stopdrag: function(ev) {
		if (this.isdragging) {
			this.stopscrolling();
			this.dragstop(ev);
			this.isdragging = false;
		}
	},


	// called when dragging has been stopped
	dragstop: function(ev) {
		var _this = this;

		this.trigger('dragstop', ev);

		// restore a mousedown'd <a>'s href (for ie8 bug)
		settimeout(function() { // must be outside of the click's execution
			if (_this.subjecthref) {
				_this.subjectel.attr('href', _this.subjecthref);
			}
		}, 0);
	},


	// call this to stop listening to the user's mouse events
	stoplistening: function(ev) {
		this.stopdrag(ev); // if there's a current drag, kill it

		if (this.islistening) {

			// remove the scroll handler if there is a scrollel
			if (this.scrollel) {
				this.scrollel.off('scroll', this.scrollhandlerproxy);
				this.scrollhandlerproxy = null;
			}

			$(document)
				.off('mousemove', this.mousemoveproxy)
				.off('mouseup', this.mouseupproxy)
				.off('selectstart', this.preventdefault);

			this.mousemoveproxy = null;
			this.mouseupproxy = null;

			this.islistening = false;
			this.listenstop(ev);
		}
	},


	// called when drag listening has stopped
	listenstop: function(ev) {
		this.trigger('listenstop', ev);
	},


	// triggers a callback. calls a function in the option hash of the same name.
	// arguments beyond the first `name` are forwarded on.
	trigger: function(name) {
		if (this.options[name]) {
			this.options[name].apply(this, array.prototype.slice.call(arguments, 1));
		}
	},


	// stops a given mouse event from doing it's native browser action. in our case, text selection.
	preventdefault: function(ev) {
		ev.preventdefault();
	},


	/* scrolling
	------------------------------------------------------------------------------------------------------------------*/


	// computes and stores the bounding rectangle of scrollel
	computescrollbounds: function() {
		var el = this.scrollel;

		this.scrollbounds = el ? getouterrect(el) : null;
			// todo: use getclientrect in future. but prevents auto scrolling when on top of scrollbars
	},


	// called when the dragging is in progress and scrolling should be updated
	updatescroll: function(ev) {
		var sensitivity = this.scrollsensitivity;
		var bounds = this.scrollbounds;
		var topcloseness, bottomcloseness;
		var leftcloseness, rightcloseness;
		var topvel = 0;
		var leftvel = 0;

		if (bounds) { // only scroll if scrollel exists

			// compute closeness to edges. valid range is from 0.0 - 1.0
			topcloseness = (sensitivity - (ev.pagey - bounds.top)) / sensitivity;
			bottomcloseness = (sensitivity - (bounds.bottom - ev.pagey)) / sensitivity;
			leftcloseness = (sensitivity - (ev.pagex - bounds.left)) / sensitivity;
			rightcloseness = (sensitivity - (bounds.right - ev.pagex)) / sensitivity;

			// translate vertical closeness into velocity.
			// mouse must be completely in bounds for velocity to happen.
			if (topcloseness >= 0 && topcloseness <= 1) {
				topvel = topcloseness * this.scrollspeed * -1; // negative. for scrolling up
			}
			else if (bottomcloseness >= 0 && bottomcloseness <= 1) {
				topvel = bottomcloseness * this.scrollspeed;
			}

			// translate horizontal closeness into velocity
			if (leftcloseness >= 0 && leftcloseness <= 1) {
				leftvel = leftcloseness * this.scrollspeed * -1; // negative. for scrolling left
			}
			else if (rightcloseness >= 0 && rightcloseness <= 1) {
				leftvel = rightcloseness * this.scrollspeed;
			}
		}

		this.setscrollvel(topvel, leftvel);
	},


	// sets the speed-of-scrolling for the scrollel
	setscrollvel: function(topvel, leftvel) {

		this.scrolltopvel = topvel;
		this.scrollleftvel = leftvel;

		this.constrainscrollvel(); // massages into realistic values

		// if there is non-zero velocity, and an animation loop hasn't already started, then start
		if ((this.scrolltopvel || this.scrollleftvel) && !this.scrollintervalid) {
			this.scrollintervalid = setinterval(
				proxy(this, 'scrollintervalfunc'), // scope to `this`
				this.scrollintervalms
			);
		}
	},


	// forces scrolltopvel and scrollleftvel to be zero if scrolling has already gone all the way
	constrainscrollvel: function() {
		var el = this.scrollel;

		if (this.scrolltopvel < 0) { // scrolling up?
			if (el.scrolltop() <= 0) { // already scrolled all the way up?
				this.scrolltopvel = 0;
			}
		}
		else if (this.scrolltopvel > 0) { // scrolling down?
			if (el.scrolltop() + el[0].clientheight >= el[0].scrollheight) { // already scrolled all the way down?
				this.scrolltopvel = 0;
			}
		}

		if (this.scrollleftvel < 0) { // scrolling left?
			if (el.scrollleft() <= 0) { // already scrolled all the left?
				this.scrollleftvel = 0;
			}
		}
		else if (this.scrollleftvel > 0) { // scrolling right?
			if (el.scrollleft() + el[0].clientwidth >= el[0].scrollwidth) { // already scrolled all the way right?
				this.scrollleftvel = 0;
			}
		}
	},


	// this function gets called during every iteration of the scrolling animation loop
	scrollintervalfunc: function() {
		var el = this.scrollel;
		var frac = this.scrollintervalms / 1000; // considering animation frequency, what the vel should be mult'd by

		// change the value of scrollel's scroll
		if (this.scrolltopvel) {
			el.scrolltop(el.scrolltop() + this.scrolltopvel * frac);
		}
		if (this.scrollleftvel) {
			el.scrollleft(el.scrollleft() + this.scrollleftvel * frac);
		}

		this.constrainscrollvel(); // since the scroll values changed, recompute the velocities

		// if scrolled all the way, which causes the vels to be zero, stop the animation loop
		if (!this.scrolltopvel && !this.scrollleftvel) {
			this.stopscrolling();
		}
	},


	// kills any existing scrolling animation loop
	stopscrolling: function() {
		if (this.scrollintervalid) {
			clearinterval(this.scrollintervalid);
			this.scrollintervalid = null;

			// when all done with scrolling, recompute positions since they probably changed
			this.scrollstop();
		}
	},


	// get called when the scrollel is scrolled (note: this is delayed via debounce)
	scrollhandler: function() {
		// recompute all coordinates, but *only* if this is *not* part of our scrolling animation
		if (!this.scrollintervalid) {
			this.scrollstop();
		}
	},


	// called when scrolling has stopped, whether through auto scroll, or the user scrolling
	scrollstop: function() {
	}

});

;;

/* tracks mouse movements over a component and raises events about which hit the mouse is over.
------------------------------------------------------------------------------------------------------------------------
options:
- subjectel
- subjectcenter
*/

var hitdraglistener = draglistener.extend({

	component: null, // converts coordinates to hits
		// methods: preparehits, releasehits, queryhit

	orighit: null, // the hit the mouse was over when listening started
	hit: null, // the hit the mouse is over
	coordadjust: null, // delta that will be added to the mouse coordinates when computing collisions


	constructor: function(component, options) {
		draglistener.call(this, options); // call the super-constructor

		this.component = component;
	},


	// called when drag listening starts (but a real drag has not necessarily began).
	// ev might be undefined if dragging was started manually.
	listenstart: function(ev) {
		var subjectel = this.subjectel;
		var subjectrect;
		var origpoint;
		var point;

		draglistener.prototype.listenstart.apply(this, arguments); // call the super-method

		this.computecoords();

		if (ev) {
			origpoint = { left: ev.pagex, top: ev.pagey };
			point = origpoint;

			// constrain the point to bounds of the element being dragged
			if (subjectel) {
				subjectrect = getouterrect(subjectel); // used for centering as well
				point = constrainpoint(point, subjectrect);
			}

			this.orighit = this.queryhit(point.left, point.top);

			// treat the center of the subject as the collision point?
			if (subjectel && this.options.subjectcenter) {

				// only consider the area the subject overlaps the hit. best for large subjects.
				// todo: skip this if hit didn't supply left/right/top/bottom
				if (this.orighit) {
					subjectrect = intersectrects(this.orighit, subjectrect) ||
						subjectrect; // in case there is no intersection
				}

				point = getrectcenter(subjectrect);
			}

			this.coordadjust = diffpoints(point, origpoint); // point - origpoint
		}
		else {
			this.orighit = null;
			this.coordadjust = null;
		}
	},


	// recomputes the drag-critical positions of elements
	computecoords: function() {
		this.component.preparehits();
		this.computescrollbounds(); // why is this here???
	},


	// called when the actual drag has started
	dragstart: function(ev) {
		var hit;

		draglistener.prototype.dragstart.apply(this, arguments); // call the super-method

		// might be different from this.orighit if the min-distance is large
		hit = this.queryhit(ev.pagex, ev.pagey);

		// report the initial hit the mouse is over
		// especially important if no min-distance and drag starts immediately
		if (hit) {
			this.hitover(hit);
		}
	},


	// called when the drag moves
	drag: function(dx, dy, ev) {
		var hit;

		draglistener.prototype.drag.apply(this, arguments); // call the super-method

		hit = this.queryhit(ev.pagex, ev.pagey);

		if (!ishitsequal(hit, this.hit)) { // a different hit than before?
			if (this.hit) {
				this.hitout();
			}
			if (hit) {
				this.hitover(hit);
			}
		}
	},


	// called when dragging has been stopped
	dragstop: function() {
		this.hitdone();
		draglistener.prototype.dragstop.apply(this, arguments); // call the super-method
	},


	// called when a the mouse has just moved over a new hit
	hitover: function(hit) {
		var isorig = ishitsequal(hit, this.orighit);

		this.hit = hit;

		this.trigger('hitover', this.hit, isorig, this.orighit);
	},


	// called when the mouse has just moved out of a hit
	hitout: function() {
		if (this.hit) {
			this.trigger('hitout', this.hit);
			this.hitdone();
			this.hit = null;
		}
	},


	// called after a hitout. also called before a dragstop
	hitdone: function() {
		if (this.hit) {
			this.trigger('hitdone', this.hit);
		}
	},


	// called when drag listening has stopped
	listenstop: function() {
		draglistener.prototype.listenstop.apply(this, arguments); // call the super-method

		this.orighit = null;
		this.hit = null;

		this.component.releasehits();
	},


	// called when scrolling has stopped, whether through auto scroll, or the user scrolling
	scrollstop: function() {
		draglistener.prototype.scrollstop.apply(this, arguments); // call the super-method

		this.computecoords(); // hits' absolute positions will be in new places. recompute
	},


	// gets the hit underneath the coordinates for the given mouse event
	queryhit: function(left, top) {

		if (this.coordadjust) {
			left += this.coordadjust.left;
			top += this.coordadjust.top;
		}

		return this.component.queryhit(left, top);
	}

});


// returns `true` if the hits are identically equal. `false` otherwise. must be from the same component.
// two null values will be considered equal, as two "out of the component" states are the same.
function ishitsequal(hit0, hit1) {

	if (!hit0 && !hit1) {
		return true;
	}

	if (hit0 && hit1) {
		return hit0.component === hit1.component &&
			ishitpropswithin(hit0, hit1) &&
			ishitpropswithin(hit1, hit0); // ensures all props are identical
	}

	return false;
}


// returns true if all of subhit's non-standard properties are within superhit
function ishitpropswithin(subhit, superhit) {
	for (var propname in subhit) {
		if (!/^(component|left|right|top|bottom)$/.test(propname)) {
			if (subhit[propname] !== superhit[propname]) {
				return false;
			}
		}
	}
	return true;
}

;;

/* creates a clone of an element and lets it track the mouse as it moves
----------------------------------------------------------------------------------------------------------------------*/

var mousefollower = class.extend({

	options: null,

	sourceel: null, // the element that will be cloned and made to look like it is dragging
	el: null, // the clone of `sourceel` that will track the mouse
	parentel: null, // the element that `el` (the clone) will be attached to

	// the initial position of el, relative to the offset parent. made to match the initial offset of sourceel
	top0: null,
	left0: null,

	// the initial position of the mouse
	mousey0: null,
	mousex0: null,

	// the number of pixels the mouse has moved from its initial position
	topdelta: null,
	leftdelta: null,

	mousemoveproxy: null, // document mousemove handler, bound to the mousefollower's `this`

	isfollowing: false,
	ishidden: false,
	isanimating: false, // doing the revert animation?

	constructor: function(sourceel, options) {
		this.options = options = options || {};
		this.sourceel = sourceel;
		this.parentel = options.parentel ? $(options.parentel) : sourceel.parent(); // default to sourceel's parent
	},


	// causes the element to start following the mouse
	start: function(ev) {
		if (!this.isfollowing) {
			this.isfollowing = true;

			this.mousey0 = ev.pagey;
			this.mousex0 = ev.pagex;
			this.topdelta = 0;
			this.leftdelta = 0;

			if (!this.ishidden) {
				this.updateposition();
			}

			$(document).on('mousemove', this.mousemoveproxy = proxy(this, 'mousemove'));
		}
	},


	// causes the element to stop following the mouse. if shouldrevert is true, will animate back to original position.
	// `callback` gets invoked when the animation is complete. if no animation, it is invoked immediately.
	stop: function(shouldrevert, callback) {
		var _this = this;
		var revertduration = this.options.revertduration;

		function complete() {
			this.isanimating = false;
			_this.removeelement();

			this.top0 = this.left0 = null; // reset state for future updateposition calls

			if (callback) {
				callback();
			}
		}

		if (this.isfollowing && !this.isanimating) { // disallow more than one stop animation at a time
			this.isfollowing = false;

			$(document).off('mousemove', this.mousemoveproxy);

			if (shouldrevert && revertduration && !this.ishidden) { // do a revert animation?
				this.isanimating = true;
				this.el.animate({
					top: this.top0,
					left: this.left0
				}, {
					duration: revertduration,
					complete: complete
				});
			}
			else {
				complete();
			}
		}
	},


	// gets the tracking element. create it if necessary
	getel: function() {
		var el = this.el;

		if (!el) {
			this.sourceel.width(); // hack to force ie8 to compute correct bounding box
			el = this.el = this.sourceel.clone()
				.css({
					position: 'absolute',
					visibility: '', // in case original element was hidden (commonly through hideevents())
					display: this.ishidden ? 'none' : '', // for when initially hidden
					margin: 0,
					right: 'auto', // erase and set width instead
					bottom: 'auto', // erase and set height instead
					width: this.sourceel.width(), // explicit height in case there was a 'right' value
					height: this.sourceel.height(), // explicit width in case there was a 'bottom' value
					opacity: this.options.opacity || '',
					zindex: this.options.zindex
				})
				.appendto(this.parentel);
		}

		return el;
	},


	// removes the tracking element if it has already been created
	removeelement: function() {
		if (this.el) {
			this.el.remove();
			this.el = null;
		}
	},


	// update the css position of the tracking element
	updateposition: function() {
		var sourceoffset;
		var origin;

		this.getel(); // ensure this.el

		// make sure origin info was computed
		if (this.top0 === null) {
			this.sourceel.width(); // hack to force ie8 to compute correct bounding box
			sourceoffset = this.sourceel.offset();
			origin = this.el.offsetparent().offset();
			this.top0 = sourceoffset.top - origin.top;
			this.left0 = sourceoffset.left - origin.left;
		}

		this.el.css({
			top: this.top0 + this.topdelta,
			left: this.left0 + this.leftdelta
		});
	},


	// gets called when the user moves the mouse
	mousemove: function(ev) {
		this.topdelta = ev.pagey - this.mousey0;
		this.leftdelta = ev.pagex - this.mousex0;

		if (!this.ishidden) {
			this.updateposition();
		}
	},


	// temporarily makes the tracking element invisible. can be called before following starts
	hide: function() {
		if (!this.ishidden) {
			this.ishidden = true;
			if (this.el) {
				this.el.hide();
			}
		}
	},


	// show the tracking element after it has been temporarily hidden
	show: function() {
		if (this.ishidden) {
			this.ishidden = false;
			this.updateposition();
			this.getel().show();
		}
	}

});

;;

/* an abstract class comprised of a "grid" of areas that each represent a specific datetime
----------------------------------------------------------------------------------------------------------------------*/

var grid = fc.grid = class.extend({

	view: null, // a view object
	isrtl: null, // shortcut to the view's isrtl option

	start: null,
	end: null,

	el: null, // the containing element
	elsbyfill: null, // a hash of jquery element sets used for rendering each fill. keyed by fill name.

	externaldragstartproxy: null, // binds the grid's scope to externaldragstart (in daygrid.events)

	// derived from options
	eventtimeformat: null,
	displayeventtime: null,
	displayeventend: null,

	minresizeduration: null, // todo: hack. set by subclasses. minumum event resize duration

	// if defined, holds the unit identified (ex: "year" or "month") that determines the level of granularity
	// of the date areas. if not defined, assumes to be day and time granularity.
	// todo: port istimescale into same system?
	largeunit: null,


	constructor: function(view) {
		this.view = view;
		this.isrtl = view.opt('isrtl');

		this.elsbyfill = {};
		this.externaldragstartproxy = proxy(this, 'externaldragstart');
	},


	/* options
	------------------------------------------------------------------------------------------------------------------*/


	// generates the format string used for event time text, if not explicitly defined by 'timeformat'
	computeeventtimeformat: function() {
		return this.view.opt('smalltimeformat');
	},


	// determines whether events should have their end times displayed, if not explicitly defined by 'displayeventtime'.
	// only applies to non-all-day events.
	computedisplayeventtime: function() {
		return true;
	},


	// determines whether events should have their end times displayed, if not explicitly defined by 'displayeventend'
	computedisplayeventend: function() {
		return true;
	},


	/* dates
	------------------------------------------------------------------------------------------------------------------*/


	// tells the grid about what period of time to display.
	// any date-related internal data should be generated.
	setrange: function(range) {
		this.start = range.start.clone();
		this.end = range.end.clone();

		this.rangeupdated();
		this.processrangeoptions();
	},


	// called when internal variables that rely on the range should be updated
	rangeupdated: function() {
	},


	// updates values that rely on options and also relate to range
	processrangeoptions: function() {
		var view = this.view;
		var displayeventtime;
		var displayeventend;

		this.eventtimeformat =
			view.opt('eventtimeformat') ||
			view.opt('timeformat') || // deprecated
			this.computeeventtimeformat();

		displayeventtime = view.opt('displayeventtime');
		if (displayeventtime == null) {
			displayeventtime = this.computedisplayeventtime(); // might be based off of range
		}

		displayeventend = view.opt('displayeventend');
		if (displayeventend == null) {
			displayeventend = this.computedisplayeventend(); // might be based off of range
		}

		this.displayeventtime = displayeventtime;
		this.displayeventend = displayeventend;
	},


	// converts a span (has unzoned start/end and any other grid-specific location information)
	// into an array of segments (pieces of events whose format is decided by the grid).
	spantosegs: function(span) {
		// subclasses must implement
	},


	// diffs the two dates, returning a duration, based on granularity of the grid
	// todo: port istimescale into this system?
	diffdates: function(a, b) {
		if (this.largeunit) {
			return diffbyunit(a, b, this.largeunit);
		}
		else {
			return diffdaytime(a, b);
		}
	},


	/* hit area
	------------------------------------------------------------------------------------------------------------------*/


	// called before one or more queryhit calls might happen. should prepare any cached coordinates for queryhit
	preparehits: function() {
	},


	// called when queryhit calls have subsided. good place to clear any coordinate caches.
	releasehits: function() {
	},


	// given coordinates from the topleft of the document, return data about the date-related area underneath.
	// can return an object with arbitrary properties (although top/right/left/bottom are encouraged).
	// must have a `grid` property, a reference to this current grid. todo: avoid this
	// the returned object will be processed by gethitspan and gethitel.
	queryhit: function(leftoffset, topoffset) {
	},


	// given position-level information about a date-related area within the grid,
	// should return an object with at least a start/end date. can provide other information as well.
	gethitspan: function(hit) {
	},


	// given position-level information about a date-related area within the grid,
	// should return a jquery element that best represents it. passed to dayclick callback.
	gethitel: function(hit) {
	},


	/* rendering
	------------------------------------------------------------------------------------------------------------------*/


	// sets the container element that the grid should render inside of.
	// does other dom-related initializations.
	setelement: function(el) {
		var _this = this;

		this.el = el;

		// attach a handler to the grid's root element.
		// jquery will take care of unregistering them when removeelement gets called.
		el.on('mousedown', function(ev) {
			if (
				!$(ev.target).is('.fc-event-container *, .fc-more') && // not an an event element, or "more.." link
				!$(ev.target).closest('.fc-popover').length // not on a popover (like the "more.." events one)
			) {
				_this.daymousedown(ev);
			}
		});

		// attach event-element-related handlers. in grid.events
		// same garbage collection note as above.
		this.bindseghandlers();

		this.bindglobalhandlers();
	},


	// removes the grid's container element from the dom. undoes any other dom-related attachments.
	// does not remove any content beforehand (doesn't clear events or call unrenderdates), unlike view
	removeelement: function() {
		this.unbindglobalhandlers();

		this.el.remove();

		// note: we don't null-out this.el for the same reasons we don't do it within view::removeelement
	},


	// renders the basic structure of grid view before any content is rendered
	renderskeleton: function() {
		// subclasses should implement
	},


	// renders the grid's date-related content (like areas that represent days/times).
	// assumes setrange has already been called and the skeleton has already been rendered.
	renderdates: function() {
		// subclasses should implement
	},


	// unrenders the grid's date-related content
	unrenderdates: function() {
		// subclasses should implement
	},


	/* handlers
	------------------------------------------------------------------------------------------------------------------*/


	// binds dom handlers to elements that reside outside the grid, such as the document
	bindglobalhandlers: function() {
		$(document).on('dragstart sortstart', this.externaldragstartproxy); // jqui
	},


	// unbinds dom handlers from elements that reside outside the grid
	unbindglobalhandlers: function() {
		$(document).off('dragstart sortstart', this.externaldragstartproxy); // jqui
	},


	// process a mousedown on an element that represents a day. for day clicking and selecting.
	daymousedown: function(ev) {
		var _this = this;
		var view = this.view;
		var isselectable = view.opt('selectable');
		var dayclickhit; // null if invalid dayclick
		var selectionspan; // null if invalid selection

		// this listener tracks a mousedown on a day element, and a subsequent drag.
		// if the drag ends on the same day, it is a 'dayclick'.
		// if 'selectable' is enabled, this listener also detects selections.
		var draglistener = new hitdraglistener(this, {
			//distance: 5, // needs more work if we want dayclick to fire correctly
			scroll: view.opt('dragscroll'),
			dragstart: function() {
				view.unselect(); // since we could be rendering a new selection, we want to clear any old one
			},
			hitover: function(hit, isorig, orighit) {
				if (orighit) { // click needs to have started on a hit
					dayclickhit = isorig ? hit : null; // single-hit selection is a day click
					if (isselectable) {
						selectionspan = _this.computeselection(
							_this.gethitspan(orighit),
							_this.gethitspan(hit)
						);
						if (selectionspan) {
							_this.renderselection(selectionspan);
						}
						else if (selectionspan === false) {
							disablecursor();
						}
					}
				}
			},
			hitout: function() {
				dayclickhit = null;
				selectionspan = null;
				_this.unrenderselection();
				enablecursor();
			},
			listenstop: function(ev) {
				if (dayclickhit) {
					view.triggerdayclick(
						_this.gethitspan(dayclickhit),
						_this.gethitel(dayclickhit),
						ev
					);
				}
				if (selectionspan) {
					// the selection will already have been rendered. just report it
					view.reportselection(selectionspan, ev);
				}
				enablecursor();
			}
		});

		draglistener.mousedown(ev); // start listening, which will eventually initiate a dragstart
	},


	/* event helper
	------------------------------------------------------------------------------------------------------------------*/
	// todo: should probably move this to grid.events, like we did event dragging / resizing


	// renders a mock event at the given event location, which contains zoned start/end properties.
	rendereventlocationhelper: function(eventlocation, sourceseg) {
		var fakeevent = this.fabricatehelperevent(eventlocation, sourceseg);

		this.renderhelper(fakeevent, sourceseg); // do the actual rendering
	},


	// builds a fake event given zoned event date properties and a segment is should be inspired from.
	// the range's end can be null, in which case the mock event that is rendered will have a null end time.
	// `sourceseg` is the internal segment object involved in the drag. if null, something external is dragging.
	fabricatehelperevent: function(eventlocation, sourceseg) {
		var fakeevent = sourceseg ? createobject(sourceseg.event) : {}; // mask the original event object if possible

		fakeevent.start = eventlocation.start.clone();
		fakeevent.end = eventlocation.end ? eventlocation.end.clone() : null;
		fakeevent.allday = null; // force it to be freshly computed by normalizeeventdates
		this.view.calendar.normalizeeventdates(fakeevent);

		// this extra classname will be useful for differentiating real events from mock events in css
		fakeevent.classname = (fakeevent.classname || []).concat('fc-helper');

		// if something external is being dragged in, don't render a resizer
		if (!sourceseg) {
			fakeevent.editable = false;
		}

		return fakeevent;
	},


	// renders a mock event. given zoned event date properties.
	renderhelper: function(eventlocation, sourceseg) {
		// subclasses must implement
	},


	// unrenders a mock event
	unrenderhelper: function() {
		// subclasses must implement
	},


	/* selection
	------------------------------------------------------------------------------------------------------------------*/


	// renders a visual indication of a selection. will highlight by default but can be overridden by subclasses.
	// given a span (unzoned start/end and other misc data)
	renderselection: function(span) {
		this.renderhighlight(span);
	},


	// unrenders any visual indications of a selection. will unrender a highlight by default.
	unrenderselection: function() {
		this.unrenderhighlight();
	},


	// given the first and last date-spans of a selection, returns another date-span object.
	// subclasses can override and provide additional data in the span object. will be passed to renderselection().
	// will return false if the selection is invalid and this should be indicated to the user.
	// will return null/undefined if a selection invalid but no error should be reported.
	computeselection: function(span0, span1) {
		var span = this.computeselectionspan(span0, span1);

		if (span && !this.view.calendar.isselectionspanallowed(span)) {
			return false;
		}

		return span;
	},


	// given two spans, must return the combination of the two.
	// todo: do this separation of concerns (combining vs validation) for event dnd/resize too.
	computeselectionspan: function(span0, span1) {
		var dates = [ span0.start, span0.end, span1.start, span1.end ];

		dates.sort(comparenumbers); // sorts chronologically. works with moments

		return { start: dates[0].clone(), end: dates[3].clone() };
	},


	/* highlight
	------------------------------------------------------------------------------------------------------------------*/


	// renders an emphasis on the given date range. given a span (unzoned start/end and other misc data)
	renderhighlight: function(span) {
		this.renderfill('highlight', this.spantosegs(span));
	},


	// unrenders the emphasis on a date range
	unrenderhighlight: function() {
		this.unrenderfill('highlight');
	},


	// generates an array of classnames for rendering the highlight. used by the fill system.
	highlightsegclasses: function() {
		return [ 'fc-highlight' ];
	},


	/* business hours
	------------------------------------------------------------------------------------------------------------------*/


	renderbusinesshours: function() {
	},


	unrenderbusinesshours: function() {
	},


	/* now indicator
	------------------------------------------------------------------------------------------------------------------*/


	getnowindicatorunit: function() {
	},


	rendernowindicator: function(date) {
	},


	unrendernowindicator: function() {
	},


	/* fill system (highlight, background events, business hours)
	--------------------------------------------------------------------------------------------------------------------
	todo: remove this system. like we did in timegrid
	*/


	// renders a set of rectangles over the given segments of time.
	// must return a subset of segs, the segs that were actually rendered.
	// responsible for populating this.elsbyfill. todo: better api for expressing this requirement
	renderfill: function(type, segs) {
		// subclasses must implement
	},


	// unrenders a specific type of fill that is currently rendered on the grid
	unrenderfill: function(type) {
		var el = this.elsbyfill[type];

		if (el) {
			el.remove();
			delete this.elsbyfill[type];
		}
	},


	// renders and assigns an `el` property for each fill segment. generic enough to work with different types.
	// only returns segments that successfully rendered.
	// to be harnessed by renderfill (implemented by subclasses).
	// analagous to renderfgsegels.
	renderfillsegels: function(type, segs) {
		var _this = this;
		var segelmethod = this[type + 'segel'];
		var html = '';
		var renderedsegs = [];
		var i;

		if (segs.length) {

			// build a large concatenation of segment html
			for (i = 0; i < segs.length; i++) {
				html += this.fillseghtml(type, segs[i]);
			}

			// grab individual elements from the combined html string. use each as the default rendering.
			// then, compute the 'el' for each segment.
			$(html).each(function(i, node) {
				var seg = segs[i];
				var el = $(node);

				// allow custom filter methods per-type
				if (segelmethod) {
					el = segelmethod.call(_this, seg, el);
				}

				if (el) { // custom filters did not cancel the render
					el = $(el); // allow custom filter to return raw dom node

					// correct element type? (would be bad if a non-td were inserted into a table for example)
					if (el.is(_this.fillsegtag)) {
						seg.el = el;
						renderedsegs.push(seg);
					}
				}
			});
		}

		return renderedsegs;
	},


	fillsegtag: 'div', // subclasses can override


	// builds the html needed for one fill segment. generic enought o work with different types.
	fillseghtml: function(type, seg) {

		// custom hooks per-type
		var classesmethod = this[type + 'segclasses'];
		var cssmethod = this[type + 'segcss'];

		var classes = classesmethod ? classesmethod.call(this, seg) : [];
		var css = csstostr(cssmethod ? cssmethod.call(this, seg) : {});

		return '<' + this.fillsegtag +
			(classes.length ? ' class="' + classes.join(' ') + '"' : '') +
			(css ? ' style="' + css + '"' : '') +
			' />';
	},



	/* generic rendering utilities for subclasses
	------------------------------------------------------------------------------------------------------------------*/


	// computes html classnames for a single-day element
	getdayclasses: function(date) {
		var view = this.view;
		var today = view.calendar.getnow();
		var classes = [ 'fc-' + dayids[date.day()] ];

		if (
			view.intervalduration.as('months') == 1 &&
			date.month() != view.intervalstart.month()
		) {
			classes.push('fc-other-month');
		}

		if (date.issame(today, 'day')) {
			classes.push(
				'fc-today',
				view.highlightstateclass
			);
		}
		else if (date < today) {
			classes.push('fc-past');
		}
		else {
			classes.push('fc-future');
		}

		return classes;
	}

});

;;

/* event-rendering and event-interaction methods for the abstract grid class
----------------------------------------------------------------------------------------------------------------------*/

grid.mixin({

	mousedoverseg: null, // the segment object the user's mouse is over. null if over nothing
	isdraggingseg: false, // is a segment being dragged? boolean
	isresizingseg: false, // is a segment being resized? boolean
	isdraggingexternal: false, // jqui-dragging an external element? boolean
	segs: null, // the *event* segments currently rendered in the grid. todo: rename to `eventsegs`


	// renders the given events onto the grid
	renderevents: function(events) {
		var bgevents = [];
		var fgevents = [];
		var i;

		for (i = 0; i < events.length; i++) {
			(isbgevent(events[i]) ? bgevents : fgevents).push(events[i]);
		}

		this.segs = [].concat( // record all segs
			this.renderbgevents(bgevents),
			this.renderfgevents(fgevents)
		);
	},


	renderbgevents: function(events) {
		var segs = this.eventstosegs(events);

		// renderbgsegs might return a subset of segs, segs that were actually rendered
		return this.renderbgsegs(segs) || segs;
	},


	renderfgevents: function(events) {
		var segs = this.eventstosegs(events);

		// renderfgsegs might return a subset of segs, segs that were actually rendered
		return this.renderfgsegs(segs) || segs;
	},


	// unrenders all events currently rendered on the grid
	unrenderevents: function() {
		this.triggersegmouseout(); // trigger an eventmouseout if user's mouse is over an event

		this.unrenderfgsegs();
		this.unrenderbgsegs();

		this.segs = null;
	},


	// retrieves all rendered segment objects currently rendered on the grid
	geteventsegs: function() {
		return this.segs || [];
	},


	/* foreground segment rendering
	------------------------------------------------------------------------------------------------------------------*/


	// renders foreground event segments onto the grid. may return a subset of segs that were rendered.
	renderfgsegs: function(segs) {
		// subclasses must implement
	},


	// unrenders all currently rendered foreground segments
	unrenderfgsegs: function() {
		// subclasses must implement
	},


	// renders and assigns an `el` property for each foreground event segment.
	// only returns segments that successfully rendered.
	// a utility that subclasses may use.
	renderfgsegels: function(segs, disableresizing) {
		var view = this.view;
		var html = '';
		var renderedsegs = [];
		var i;

		if (segs.length) { // don't build an empty html string

			// build a large concatenation of event segment html
			for (i = 0; i < segs.length; i++) {
				html += this.fgseghtml(segs[i], disableresizing);
			}

			// grab individual elements from the combined html string. use each as the default rendering.
			// then, compute the 'el' for each segment. an el might be null if the eventrender callback returned false.
			$(html).each(function(i, node) {
				var seg = segs[i];
				var el = view.resolveeventel(seg.event, $(node));

				if (el) {
					el.data('fc-seg', seg); // used by handlers
					seg.el = el;
					renderedsegs.push(seg);
				}
			});
		}

		return renderedsegs;
	},


	// generates the html for the default rendering of a foreground event segment. used by renderfgsegels()
	fgseghtml: function(seg, disableresizing) {
		// subclasses should implement
	},


	/* background segment rendering
	------------------------------------------------------------------------------------------------------------------*/


	// renders the given background event segments onto the grid.
	// returns a subset of the segs that were actually rendered.
	renderbgsegs: function(segs) {
		return this.renderfill('bgevent', segs);
	},


	// unrenders all the currently rendered background event segments
	unrenderbgsegs: function() {
		this.unrenderfill('bgevent');
	},


	// renders a background event element, given the default rendering. called by the fill system.
	bgeventsegel: function(seg, el) {
		return this.view.resolveeventel(seg.event, el); // will filter through eventrender
	},


	// generates an array of classnames to be used for the default rendering of a background event.
	// called by the fill system.
	bgeventsegclasses: function(seg) {
		var event = seg.event;
		var source = event.source || {};

		return [ 'fc-bgevent' ].concat(
			event.classname,
			source.classname || []
		);
	},


	// generates a semicolon-separated css string to be used for the default rendering of a background event.
	// called by the fill system.
	bgeventsegcss: function(seg) {
		return {
			'background-color': this.getsegskincss(seg)['background-color']
		};
	},


	// generates an array of classnames to be used for the rendering business hours overlay. called by the fill system.
	businesshourssegclasses: function(seg) {
		return [ 'fc-nonbusiness', 'fc-bgevent' ];
	},


	/* handlers
	------------------------------------------------------------------------------------------------------------------*/


	// attaches event-element-related handlers to the container element and leverage bubbling
	bindseghandlers: function() {
		var _this = this;
		var view = this.view;

		$.each(
			{
				mouseenter: function(seg, ev) {
					_this.triggersegmouseover(seg, ev);
				},
				mouseleave: function(seg, ev) {
					_this.triggersegmouseout(seg, ev);
				},
				click: function(seg, ev) {
					return view.trigger('eventclick', this, seg.event, ev); // can return `false` to cancel
				},
				mousedown: function(seg, ev) {
					if ($(ev.target).is('.fc-resizer') && view.iseventresizable(seg.event)) {
						_this.segresizemousedown(seg, ev, $(ev.target).is('.fc-start-resizer'));
					}
					else if (view.iseventdraggable(seg.event)) {
						_this.segdragmousedown(seg, ev);
					}
				}
			},
			function(name, func) {
				// attach the handler to the container element and only listen for real event elements via bubbling
				_this.el.on(name, '.fc-event-container > *', function(ev) {
					var seg = $(this).data('fc-seg'); // grab segment data. put there by view::renderevents

					// only call the handlers if there is not a drag/resize in progress
					if (seg && !_this.isdraggingseg && !_this.isresizingseg) {
						return func.call(this, seg, ev); // `this` will be the event element
					}
				});
			}
		);
	},


	// updates internal state and triggers handlers for when an event element is moused over
	triggersegmouseover: function(seg, ev) {
		if (!this.mousedoverseg) {
			this.mousedoverseg = seg;
			this.view.trigger('eventmouseover', seg.el[0], seg.event, ev);
		}
	},


	// updates internal state and triggers handlers for when an event element is moused out.
	// can be given no arguments, in which case it will mouseout the segment that was previously moused over.
	triggersegmouseout: function(seg, ev) {
		ev = ev || {}; // if given no args, make a mock mouse event

		if (this.mousedoverseg) {
			seg = seg || this.mousedoverseg; // if given no args, use the currently moused-over segment
			this.mousedoverseg = null;
			this.view.trigger('eventmouseout', seg.el[0], seg.event, ev);
		}
	},


	/* event dragging
	------------------------------------------------------------------------------------------------------------------*/


	// called when the user does a mousedown on an event, which might lead to dragging.
	// generic enough to work with any type of grid.
	segdragmousedown: function(seg, ev) {
		var _this = this;
		var view = this.view;
		var calendar = view.calendar;
		var el = seg.el;
		var event = seg.event;
		var droplocation; // zoned event date properties

		// a clone of the original element that will move with the mouse
		var mousefollower = new mousefollower(seg.el, {
			parentel: view.el,
			opacity: view.opt('dragopacity'),
			revertduration: view.opt('dragrevertduration'),
			zindex: 2 // one above the .fc-view
		});

		// tracks mouse movement over the *view's* coordinate map. allows dragging and dropping between subcomponents
		// of the view.
		var draglistener = new hitdraglistener(view, {
			distance: 5,
			scroll: view.opt('dragscroll'),
			subjectel: el,
			subjectcenter: true,
			listenstart: function(ev) {
				mousefollower.hide(); // don't show until we know this is a real drag
				mousefollower.start(ev);
			},
			dragstart: function(ev) {
				_this.triggersegmouseout(seg, ev); // ensure a mouseout on the manipulated event has been reported
				_this.segdragstart(seg, ev);
				view.hideevent(event); // hide all event segments. our mousefollower will take over
			},
			hitover: function(hit, isorig, orighit) {

				// starting hit could be forced (daygrid.limit)
				if (seg.hit) {
					orighit = seg.hit;
				}

				// since we are querying the parent view, might not belong to this grid
				droplocation = _this.computeeventdrop(
					orighit.component.gethitspan(orighit),
					hit.component.gethitspan(hit),
					event
				);

				if (droplocation && !calendar.iseventspanallowed(_this.eventtospan(droplocation), event)) {
					disablecursor();
					droplocation = null;
				}

				// if a valid drop location, have the subclass render a visual indication
				if (droplocation && view.renderdrag(droplocation, seg)) {
					mousefollower.hide(); // if the subclass is already using a mock event "helper", hide our own
				}
				else {
					mousefollower.show(); // otherwise, have the helper follow the mouse (no snapping)
				}

				if (isorig) {
					droplocation = null; // needs to have moved hits to be a valid drop
				}
			},
			hitout: function() { // called before mouse moves to a different hit or moved out of all hits
				view.unrenderdrag(); // unrender whatever was done in renderdrag
				mousefollower.show(); // show in case we are moving out of all hits
				droplocation = null;
			},
			hitdone: function() { // called after a hitout or before a dragstop
				enablecursor();
			},
			dragstop: function(ev) {
				// do revert animation if hasn't changed. calls a callback when finished (whether animation or not)
				mousefollower.stop(!droplocation, function() {
					view.unrenderdrag();
					view.showevent(event);
					_this.segdragstop(seg, ev);

					if (droplocation) {
						view.reporteventdrop(event, droplocation, this.largeunit, el, ev);
					}
				});
			},
			listenstop: function() {
				mousefollower.stop(); // put in listenstop in case there was a mousedown but the drag never started
			}
		});

		draglistener.mousedown(ev); // start listening, which will eventually lead to a dragstart
	},


	// called before event segment dragging starts
	segdragstart: function(seg, ev) {
		this.isdraggingseg = true;
		this.view.trigger('eventdragstart', seg.el[0], seg.event, ev, {}); // last argument is jqui dummy
	},


	// called after event segment dragging stops
	segdragstop: function(seg, ev) {
		this.isdraggingseg = false;
		this.view.trigger('eventdragstop', seg.el[0], seg.event, ev, {}); // last argument is jqui dummy
	},


	// given the spans an event drag began, and the span event was dropped, calculates the new zoned start/end/allday
	// values for the event. subclasses may override and set additional properties to be used by renderdrag.
	// a falsy returned value indicates an invalid drop.
	// does not consider overlap/constraint.
	computeeventdrop: function(startspan, endspan, event) {
		var calendar = this.view.calendar;
		var dragstart = startspan.start;
		var dragend = endspan.start;
		var delta;
		var droplocation; // zoned event date properties

		if (dragstart.hastime() === dragend.hastime()) {
			delta = this.diffdates(dragend, dragstart);

			// if an all-day event was in a timed area and it was dragged to a different time,
			// guarantee an end and adjust start/end to have times
			if (event.allday && durationhastime(delta)) {
				droplocation = {
					start: event.start.clone(),
					end: calendar.geteventend(event), // will be an ambig day
					allday: false // for normalizeeventtimes
				};
				calendar.normalizeeventtimes(droplocation);
			}
			// othewise, work off existing values
			else {
				droplocation = {
					start: event.start.clone(),
					end: event.end ? event.end.clone() : null,
					allday: event.allday // keep it the same
				};
			}

			droplocation.start.add(delta);
			if (droplocation.end) {
				droplocation.end.add(delta);
			}
		}
		else {
			// if switching from day <-> timed, start should be reset to the dropped date, and the end cleared
			droplocation = {
				start: dragend.clone(),
				end: null, // end should be cleared
				allday: !dragend.hastime()
			};
		}

		return droplocation;
	},


	// utility for apply dragopacity to a jquery set
	applydragopacity: function(els) {
		var opacity = this.view.opt('dragopacity');

		if (opacity != null) {
			els.each(function(i, node) {
				// don't use jquery (will set an ie filter), do it the old fashioned way.
				// in ie8, a helper element will disappears if there's a filter.
				node.style.opacity = opacity;
			});
		}
	},


	/* external element dragging
	------------------------------------------------------------------------------------------------------------------*/


	// called when a jquery ui drag is initiated anywhere in the dom
	externaldragstart: function(ev, ui) {
		var view = this.view;
		var el;
		var accept;

		if (view.opt('droppable')) { // only listen if this setting is on
			el = $((ui ? ui.item : null) || ev.target);

			// test that the dragged element passes the dropaccept selector or filter function.
			// fyi, the default is "*" (matches all)
			accept = view.opt('dropaccept');
			if ($.isfunction(accept) ? accept.call(el[0], el) : el.is(accept)) {
				if (!this.isdraggingexternal) { // prevent double-listening if fired twice
					this.listentoexternaldrag(el, ev, ui);
				}
			}
		}
	},


	// called when a jquery ui drag starts and it needs to be monitored for dropping
	listentoexternaldrag: function(el, ev, ui) {
		var _this = this;
		var calendar = this.view.calendar;
		var meta = getdraggedelmeta(el); // extra data about event drop, including possible event to create
		var droplocation; // a null value signals an unsuccessful drag

		// listener that tracks mouse movement over date-associated pixel regions
		var draglistener = new hitdraglistener(this, {
			listenstart: function() {
				_this.isdraggingexternal = true;
			},
			hitover: function(hit) {
				droplocation = _this.computeexternaldrop(
					hit.component.gethitspan(hit), // since we are querying the parent view, might not belong to this grid
					meta
				);

				if ( // invalid hit?
					droplocation &&
					!calendar.isexternalspanallowed(_this.eventtospan(droplocation), droplocation, meta.eventprops)
				) {
					disablecursor();
					droplocation = null;
				}

				if (droplocation) {
					_this.renderdrag(droplocation); // called without a seg parameter
				}
			},
			hitout: function() {
				droplocation = null; // signal unsuccessful
			},
			hitdone: function() { // called after a hitout or before a dragstop
				enablecursor();
				_this.unrenderdrag();
			},
			dragstop: function() {
				if (droplocation) { // element was dropped on a valid hit
					_this.view.reportexternaldrop(meta, droplocation, el, ev, ui);
				}
			},
			listenstop: function() {
				_this.isdraggingexternal = false;
			}
		});

		draglistener.startdrag(ev); // start listening immediately
	},


	// given a hit to be dropped upon, and misc data associated with the jqui drag (guaranteed to be a plain object),
	// returns the zoned start/end dates for the event that would result from the hypothetical drop. end might be null.
	// returning a null value signals an invalid drop hit.
	// does not consider overlap/constraint.
	computeexternaldrop: function(span, meta) {
		var calendar = this.view.calendar;
		var droplocation = {
			start: calendar.applytimezone(span.start), // simulate a zoned event start date
			end: null
		};

		// if dropped on an all-day span, and element's metadata specified a time, set it
		if (meta.starttime && !droplocation.start.hastime()) {
			droplocation.start.time(meta.starttime);
		}

		if (meta.duration) {
			droplocation.end = droplocation.start.clone().add(meta.duration);
		}

		return droplocation;
	},



	/* drag rendering (for both events and an external elements)
	------------------------------------------------------------------------------------------------------------------*/


	// renders a visual indication of an event or external element being dragged.
	// `droplocation` contains hypothetical start/end/allday values the event would have if dropped. end can be null.
	// `seg` is the internal segment object that is being dragged. if dragging an external element, `seg` is null.
	// a truthy returned value indicates this method has rendered a helper element.
	renderdrag: function(droplocation, seg) {
		// subclasses must implement
	},


	// unrenders a visual indication of an event or external element being dragged
	unrenderdrag: function() {
		// subclasses must implement
	},


	/* resizing
	------------------------------------------------------------------------------------------------------------------*/


	// called when the user does a mousedown on an event's resizer, which might lead to resizing.
	// generic enough to work with any type of grid.
	segresizemousedown: function(seg, ev, isstart) {
		var _this = this;
		var view = this.view;
		var calendar = view.calendar;
		var el = seg.el;
		var event = seg.event;
		var eventend = calendar.geteventend(event);
		var resizelocation; // zoned event date properties. falsy if invalid resize

		// tracks mouse movement over the *grid's* coordinate map
		var draglistener = new hitdraglistener(this, {
			distance: 5,
			scroll: view.opt('dragscroll'),
			subjectel: el,
			dragstart: function(ev) {
				_this.triggersegmouseout(seg, ev); // ensure a mouseout on the manipulated event has been reported
				_this.segresizestart(seg, ev);
			},
			hitover: function(hit, isorig, orighit) {
				var orighitspan = _this.gethitspan(orighit);
				var hitspan = _this.gethitspan(hit);

				resizelocation = isstart ?
					_this.computeeventstartresize(orighitspan, hitspan, event) :
					_this.computeeventendresize(orighitspan, hitspan, event);

				if (resizelocation) {
					if (!calendar.iseventspanallowed(_this.eventtospan(resizelocation), event)) {
						disablecursor();
						resizelocation = null;
					}
					// no change? (todo: how does this work with timezones?)
					else if (resizelocation.start.issame(event.start) && resizelocation.end.issame(eventend)) {
						resizelocation = null;
					}
				}

				if (resizelocation) {
					view.hideevent(event);
					_this.rendereventresize(resizelocation, seg);
				}
			},
			hitout: function() { // called before mouse moves to a different hit or moved out of all hits
				resizelocation = null;
			},
			hitdone: function() { // resets the rendering to show the original event
				_this.unrendereventresize();
				view.showevent(event);
				enablecursor();
			},
			dragstop: function(ev) {
				_this.segresizestop(seg, ev);

				if (resizelocation) { // valid date to resize to?
					view.reporteventresize(event, resizelocation, this.largeunit, el, ev);
				}
			}
		});

		draglistener.mousedown(ev); // start listening, which will eventually lead to a dragstart
	},


	// called before event segment resizing starts
	segresizestart: function(seg, ev) {
		this.isresizingseg = true;
		this.view.trigger('eventresizestart', seg.el[0], seg.event, ev, {}); // last argument is jqui dummy
	},


	// called after event segment resizing stops
	segresizestop: function(seg, ev) {
		this.isresizingseg = false;
		this.view.trigger('eventresizestop', seg.el[0], seg.event, ev, {}); // last argument is jqui dummy
	},


	// returns new date-information for an event segment being resized from its start
	computeeventstartresize: function(startspan, endspan, event) {
		return this.computeeventresize('start', startspan, endspan, event);
	},


	// returns new date-information for an event segment being resized from its end
	computeeventendresize: function(startspan, endspan, event) {
		return this.computeeventresize('end', startspan, endspan, event);
	},


	// returns new zoned date information for an event segment being resized from its start or end
	// `type` is either 'start' or 'end'.
	// does not consider overlap/constraint.
	computeeventresize: function(type, startspan, endspan, event) {
		var calendar = this.view.calendar;
		var delta = this.diffdates(endspan[type], startspan[type]);
		var resizelocation; // zoned event date properties
		var defaultduration;

		// build original values to work from, guaranteeing a start and end
		resizelocation = {
			start: event.start.clone(),
			end: calendar.geteventend(event),
			allday: event.allday
		};

		// if an all-day event was in a timed area and was resized to a time, adjust start/end to have times
		if (resizelocation.allday && durationhastime(delta)) {
			resizelocation.allday = false;
			calendar.normalizeeventtimes(resizelocation);
		}

		resizelocation[type].add(delta); // apply delta to start or end

		// if the event was compressed too small, find a new reasonable duration for it
		if (!resizelocation.start.isbefore(resizelocation.end)) {

			defaultduration =
				this.minresizeduration || // todo: hack
				(event.allday ?
					calendar.defaultalldayeventduration :
					calendar.defaulttimedeventduration);

			if (type == 'start') { // resizing the start?
				resizelocation.start = resizelocation.end.clone().subtract(defaultduration);
			}
			else { // resizing the end?
				resizelocation.end = resizelocation.start.clone().add(defaultduration);
			}
		}

		return resizelocation;
	},


	// renders a visual indication of an event being resized.
	// `range` has the updated dates of the event. `seg` is the original segment object involved in the drag.
	rendereventresize: function(range, seg) {
		// subclasses must implement
	},


	// unrenders a visual indication of an event being resized.
	unrendereventresize: function() {
		// subclasses must implement
	},


	/* rendering utils
	------------------------------------------------------------------------------------------------------------------*/


	// compute the text that should be displayed on an event's element.
	// `range` can be the event object itself, or something range-like, with at least a `start`.
	// if event times are disabled, or the event has no time, will return a blank string.
	// if not specified, formatstr will default to the eventtimeformat setting,
	// and displayend will default to the displayeventend setting.
	geteventtimetext: function(range, formatstr, displayend) {

		if (formatstr == null) {
			formatstr = this.eventtimeformat;
		}

		if (displayend == null) {
			displayend = this.displayeventend;
		}

		if (this.displayeventtime && range.start.hastime()) {
			if (displayend && range.end) {
				return this.view.formatrange(range, formatstr);
			}
			else {
				return range.start.format(formatstr);
			}
		}

		return '';
	},


	// generic utility for generating the html classnames for an event segment's element
	getsegclasses: function(seg, isdraggable, isresizable) {
		var event = seg.event;
		var classes = [
			'fc-event',
			seg.isstart ? 'fc-start' : 'fc-not-start',
			seg.isend ? 'fc-end' : 'fc-not-end'
		].concat(
			event.classname,
			event.source ? event.source.classname : []
		);

		if (isdraggable) {
			classes.push('fc-draggable');
		}
		if (isresizable) {
			classes.push('fc-resizable');
		}

		return classes;
	},


	// utility for generating event skin-related css properties
	getsegskincss: function(seg) {
		var event = seg.event;
		var view = this.view;
		var source = event.source || {};
		var eventcolor = event.color;
		var sourcecolor = source.color;
		var optioncolor = view.opt('eventcolor');

		return {
			'background-color':
				event.backgroundcolor ||
				eventcolor ||
				source.backgroundcolor ||
				sourcecolor ||
				view.opt('eventbackgroundcolor') ||
				optioncolor,
			'border-color':
				event.bordercolor ||
				eventcolor ||
				source.bordercolor ||
				sourcecolor ||
				view.opt('eventbordercolor') ||
				optioncolor,
			color:
				event.textcolor ||
				source.textcolor ||
				view.opt('eventtextcolor')
		};
	},


	/* converting events -> eventrange -> eventspan -> eventsegs
	------------------------------------------------------------------------------------------------------------------*/


	// generates an array of segments for the given single event
	// can accept an event "location" as well (which only has start/end and no allday)
	eventtosegs: function(event) {
		return this.eventstosegs([ event ]);
	},


	eventtospan: function(event) {
		return this.eventtospans(event)[0];
	},


	// generates spans (always unzoned) for the given event.
	// does not do any inverting for inverse-background events.
	// can accept an event "location" as well (which only has start/end and no allday)
	eventtospans: function(event) {
		var range = this.eventtorange(event);
		return this.eventrangetospans(range, event);
	},



	// converts an array of event objects into an array of event segment objects.
	// a custom `segslicefunc` may be given for arbitrarily slicing up events.
	// doesn't guarantee an order for the resulting array.
	eventstosegs: function(allevents, segslicefunc) {
		var _this = this;
		var eventsbyid = groupeventsbyid(allevents);
		var segs = [];

		$.each(eventsbyid, function(id, events) {
			var ranges = [];
			var i;

			for (i = 0; i < events.length; i++) {
				ranges.push(_this.eventtorange(events[i]));
			}

			// inverse-background events (utilize only the first event in calculations)
			if (isinversebgevent(events[0])) {
				ranges = _this.invertranges(ranges);

				for (i = 0; i < ranges.length; i++) {
					segs.push.apply(segs, // append to
						_this.eventrangetosegs(ranges[i], events[0], segslicefunc));
				}
			}
			// normal event ranges
			else {
				for (i = 0; i < ranges.length; i++) {
					segs.push.apply(segs, // append to
						_this.eventrangetosegs(ranges[i], events[i], segslicefunc));
				}
			}
		});

		return segs;
	},


	// generates the unzoned start/end dates an event appears to occupy
	// can accept an event "location" as well (which only has start/end and no allday)
	eventtorange: function(event) {
		return {
			start: event.start.clone().stripzone(),
			end: (
				event.end ?
					event.end.clone() :
					// derive the end from the start and allday. compute allday if necessary
					this.view.calendar.getdefaulteventend(
						event.allday != null ?
							event.allday :
							!event.start.hastime(),
						event.start
					)
			).stripzone()
		};
	},


	// given an event's range (unzoned start/end), and the event itself,
	// slice into segments (using the segslicefunc function if specified)
	eventrangetosegs: function(range, event, segslicefunc) {
		var spans = this.eventrangetospans(range, event);
		var segs = [];
		var i;

		for (i = 0; i < spans.length; i++) {
			segs.push.apply(segs, // append to
				this.eventspantosegs(spans[i], event, segslicefunc));
		}

		return segs;
	},


	// given an event's unzoned date range, return an array of "span" objects.
	// subclasses can override.
	eventrangetospans: function(range, event) {
		return [ $.extend({}, range) ]; // copy into a single-item array
	},


	// given an event's span (unzoned start/end and other misc data), and the event itself,
	// slices into segments and attaches event-derived properties to them.
	eventspantosegs: function(span, event, segslicefunc) {
		var segs = segslicefunc ? segslicefunc(span) : this.spantosegs(span);
		var i, seg;

		for (i = 0; i < segs.length; i++) {
			seg = segs[i];
			seg.event = event;
			seg.eventstartms = +span.start; // todo: not the best name after making spans unzoned
			seg.eventdurationms = span.end - span.start;
		}

		return segs;
	},


	// produces a new array of range objects that will cover all the time not covered by the given ranges.
	// side effect: will mutate the given array and will use its date references.
	invertranges: function(ranges) {
		var view = this.view;
		var viewstart = view.start.clone(); // need a copy
		var viewend = view.end.clone(); // need a copy
		var inverseranges = [];
		var start = viewstart; // the end of the previous range. the start of the new range
		var i, range;

		// ranges need to be in order. required for our date-walking algorithm
		ranges.sort(compareranges);

		for (i = 0; i < ranges.length; i++) {
			range = ranges[i];

			// add the span of time before the event (if there is any)
			if (range.start > start) { // compare millisecond time (skip any ambig logic)
				inverseranges.push({
					start: start,
					end: range.start
				});
			}

			start = range.end;
		}

		// add the span of time after the last event (if there is any)
		if (start < viewend) { // compare millisecond time (skip any ambig logic)
			inverseranges.push({
				start: start,
				end: viewend
			});
		}

		return inverseranges;
	},


	sorteventsegs: function(segs) {
		segs.sort(proxy(this, 'compareeventsegs'));
	},


	// a cmp function for determining which segments should take visual priority
	compareeventsegs: function(seg1, seg2) {
		return seg1.eventstartms - seg2.eventstartms || // earlier events go first
			seg2.eventdurationms - seg1.eventdurationms || // tie? longer events go first
			seg2.event.allday - seg1.event.allday || // tie? put all-day events first (booleans cast to 0/1)
			comparebyfieldspecs(seg1.event, seg2.event, this.view.eventorderspecs);
	}

});


/* utilities
----------------------------------------------------------------------------------------------------------------------*/


function isbgevent(event) { // returns true if background or inverse-background
	var rendering = geteventrendering(event);
	return rendering === 'background' || rendering === 'inverse-background';
}
fc.isbgevent = isbgevent; // export


function isinversebgevent(event) {
	return geteventrendering(event) === 'inverse-background';
}


function geteventrendering(event) {
	return firstdefined((event.source || {}).rendering, event.rendering);
}


function groupeventsbyid(events) {
	var eventsbyid = {};
	var i, event;

	for (i = 0; i < events.length; i++) {
		event = events[i];
		(eventsbyid[event._id] || (eventsbyid[event._id] = [])).push(event);
	}

	return eventsbyid;
}


// a cmp function for determining which non-inverted "ranges" (see above) happen earlier
function compareranges(range1, range2) {
	return range1.start - range2.start; // earlier ranges go first
}


/* external-dragging-element data
----------------------------------------------------------------------------------------------------------------------*/

// require all html5 data-* attributes used by fullcalendar to have this prefix.
// a value of '' will query attributes like data-event. a value of 'fc' will query attributes like data-fc-event.
fc.dataattrprefix = '';

// given a jquery element that might represent a dragged fullcalendar event, returns an intermediate data structure
// to be used for event object creation.
// a defined `.eventprops`, even when empty, indicates that an event should be created.
function getdraggedelmeta(el) {
	var prefix = fc.dataattrprefix;
	var eventprops; // properties for creating the event, not related to date/time
	var starttime; // a duration
	var duration;
	var stick;

	if (prefix) { prefix += '-'; }
	eventprops = el.data(prefix + 'event') || null;

	if (eventprops) {
		if (typeof eventprops === 'object') {
			eventprops = $.extend({}, eventprops); // make a copy
		}
		else { // something like 1 or true. still signal event creation
			eventprops = {};
		}

		// pluck special-cased date/time properties
		starttime = eventprops.start;
		if (starttime == null) { starttime = eventprops.time; } // accept 'time' as well
		duration = eventprops.duration;
		stick = eventprops.stick;
		delete eventprops.start;
		delete eventprops.time;
		delete eventprops.duration;
		delete eventprops.stick;
	}

	// fallback to standalone attribute values for each of the date/time properties
	if (starttime == null) { starttime = el.data(prefix + 'start'); }
	if (starttime == null) { starttime = el.data(prefix + 'time'); } // accept 'time' as well
	if (duration == null) { duration = el.data(prefix + 'duration'); }
	if (stick == null) { stick = el.data(prefix + 'stick'); }

	// massage into correct data types
	starttime = starttime != null ? moment.duration(starttime) : null;
	duration = duration != null ? moment.duration(duration) : null;
	stick = boolean(stick);

	return { eventprops: eventprops, starttime: starttime, duration: duration, stick: stick };
}


;;

/*
a set of rendering and date-related methods for a visual component comprised of one or more rows of day columns.
prerequisite: the object being mixed into needs to be a *grid*
*/
var daytablemixin = fc.daytablemixin = {

	breakonweeks: false, // should create a new row for each week?
	daydates: null, // whole-day dates for each column. left to right
	dayindices: null, // for each day from start, the offset
	daysperrow: null,
	rowcnt: null,
	colcnt: null,
	colheadformat: null,


	// populates internal variables used for date calculation and rendering
	updatedaytable: function() {
		var view = this.view;
		var date = this.start.clone();
		var dayindex = -1;
		var dayindices = [];
		var daydates = [];
		var daysperrow;
		var firstday;
		var rowcnt;

		while (date.isbefore(this.end)) { // loop each day from start to end
			if (view.ishiddenday(date)) {
				dayindices.push(dayindex + 0.5); // mark that it's between indices
			}
			else {
				dayindex++;
				dayindices.push(dayindex);
				daydates.push(date.clone());
			}
			date.add(1, 'days');
		}

		if (this.breakonweeks) {
			// count columns until the day-of-week repeats
			firstday = daydates[0].day();
			for (daysperrow = 1; daysperrow < daydates.length; daysperrow++) {
				if (daydates[daysperrow].day() == firstday) {
					break;
				}
			}
			rowcnt = math.ceil(daydates.length / daysperrow);
		}
		else {
			rowcnt = 1;
			daysperrow = daydates.length;
		}

		this.daydates = daydates;
		this.dayindices = dayindices;
		this.daysperrow = daysperrow;
		this.rowcnt = rowcnt;
		
		this.updatedaytablecols();
	},


	// computes and assigned the colcnt property and updates any options that may be computed from it
	updatedaytablecols: function() {
		this.colcnt = this.computecolcnt();
		this.colheadformat = this.view.opt('columnformat') || this.computecolheadformat();
	},


	// determines how many columns there should be in the table
	computecolcnt: function() {
		return this.daysperrow;
	},


	// computes the ambiguously-timed moment for the given cell
	getcelldate: function(row, col) {
		return this.daydates[
				this.getcelldayindex(row, col)
			].clone();
	},


	// computes the ambiguously-timed date range for the given cell
	getcellrange: function(row, col) {
		var start = this.getcelldate(row, col);
		var end = start.clone().add(1, 'days');

		return { start: start, end: end };
	},


	// returns the number of day cells, chronologically, from the first of the grid (0-based)
	getcelldayindex: function(row, col) {
		return row * this.daysperrow + this.getcoldayindex(col);
	},


	// returns the numner of day cells, chronologically, from the first cell in *any given row*
	getcoldayindex: function(col) {
		if (this.isrtl) {
			return this.colcnt - 1 - col;
		}
		else {
			return col;
		}
	},


	// given a date, returns its chronolocial cell-index from the first cell of the grid.
	// if the date lies between cells (because of hiddendays), returns a floating-point value between offsets.
	// if before the first offset, returns a negative number.
	// if after the last offset, returns an offset past the last cell offset.
	// only works for *start* dates of cells. will not work for exclusive end dates for cells.
	getdatedayindex: function(date) {
		var dayindices = this.dayindices;
		var dayoffset = date.diff(this.start, 'days');

		if (dayoffset < 0) {
			return dayindices[0] - 1;
		}
		else if (dayoffset >= dayindices.length) {
			return dayindices[dayindices.length - 1] + 1;
		}
		else {
			return dayindices[dayoffset];
		}
	},


	/* options
	------------------------------------------------------------------------------------------------------------------*/


	// computes a default column header formatting string if `colformat` is not explicitly defined
	computecolheadformat: function() {
		// if more than one week row, or if there are a lot of columns with not much space,
		// put just the day numbers will be in each cell
		if (this.rowcnt > 1 || this.colcnt > 10) {
			return 'ddd'; // "sat"
		}
		// multiple days, so full single date string won't be in title text
		else if (this.colcnt > 1) {
			return this.view.opt('dayofmonthformat'); // "sat 12/10"
		}
		// single day, so full single date string will probably be in title text
		else {
			return 'dddd'; // "saturday"
		}
	},


	/* slicing
	------------------------------------------------------------------------------------------------------------------*/


	// slices up a date range into a segment for every week-row it intersects with
	slicerangebyrow: function(range) {
		var daysperrow = this.daysperrow;
		var normalrange = this.view.computedayrange(range); // make whole-day range, considering nextdaythreshold
		var rangefirst = this.getdatedayindex(normalrange.start); // inclusive first index
		var rangelast = this.getdatedayindex(normalrange.end.clone().subtract(1, 'days')); // inclusive last index
		var segs = [];
		var row;
		var rowfirst, rowlast; // inclusive day-index range for current row
		var segfirst, seglast; // inclusive day-index range for segment

		for (row = 0; row < this.rowcnt; row++) {
			rowfirst = row * daysperrow;
			rowlast = rowfirst + daysperrow - 1;

			// intersect segment's offset range with the row's
			segfirst = math.max(rangefirst, rowfirst);
			seglast = math.min(rangelast, rowlast);

			// deal with in-between indices
			segfirst = math.ceil(segfirst); // in-between starts round to next cell
			seglast = math.floor(seglast); // in-between ends round to prev cell

			if (segfirst <= seglast) { // was there any intersection with the current row?
				segs.push({
					row: row,

					// normalize to start of row
					firstrowdayindex: segfirst - rowfirst,
					lastrowdayindex: seglast - rowfirst,

					// must be matching integers to be the segment's start/end
					isstart: segfirst === rangefirst,
					isend: seglast === rangelast
				});
			}
		}

		return segs;
	},


	// slices up a date range into a segment for every day-cell it intersects with.
	// todo: make more dry with slicerangebyrow somehow.
	slicerangebyday: function(range) {
		var daysperrow = this.daysperrow;
		var normalrange = this.view.computedayrange(range); // make whole-day range, considering nextdaythreshold
		var rangefirst = this.getdatedayindex(normalrange.start); // inclusive first index
		var rangelast = this.getdatedayindex(normalrange.end.clone().subtract(1, 'days')); // inclusive last index
		var segs = [];
		var row;
		var rowfirst, rowlast; // inclusive day-index range for current row
		var i;
		var segfirst, seglast; // inclusive day-index range for segment

		for (row = 0; row < this.rowcnt; row++) {
			rowfirst = row * daysperrow;
			rowlast = rowfirst + daysperrow - 1;

			for (i = rowfirst; i <= rowlast; i++) {

				// intersect segment's offset range with the row's
				segfirst = math.max(rangefirst, i);
				seglast = math.min(rangelast, i);

				// deal with in-between indices
				segfirst = math.ceil(segfirst); // in-between starts round to next cell
				seglast = math.floor(seglast); // in-between ends round to prev cell

				if (segfirst <= seglast) { // was there any intersection with the current row?
					segs.push({
						row: row,

						// normalize to start of row
						firstrowdayindex: segfirst - rowfirst,
						lastrowdayindex: seglast - rowfirst,

						// must be matching integers to be the segment's start/end
						isstart: segfirst === rangefirst,
						isend: seglast === rangelast
					});
				}
			}
		}

		return segs;
	},


	/* header rendering
	------------------------------------------------------------------------------------------------------------------*/


	renderheadhtml: function() {
		var view = this.view;

		return '' +
			'<div class="fc-row ' + view.widgetheaderclass + '">' +
				'<table>' +
					'<thead>' +
						this.renderheadtrhtml() +
					'</thead>' +
				'</table>' +
			'</div>';
	},


	renderheadintrohtml: function() {
		return this.renderintrohtml(); // fall back to generic
	},


	renderheadtrhtml: function() {
		return '' +
			'<tr>' +
				(this.isrtl ? '' : this.renderheadintrohtml()) +
				this.renderheaddatecellshtml() +
				(this.isrtl ? this.renderheadintrohtml() : '') +
			'</tr>';
	},


	renderheaddatecellshtml: function() {
		var htmls = [];
		var col, date;

		for (col = 0; col < this.colcnt; col++) {
			date = this.getcelldate(0, col);
			htmls.push(this.renderheaddatecellhtml(date));
		}

		return htmls.join('');
	},


	// todo: when internalapiversion, accept an object for html attributes
	// (colspan should be no different)
	renderheaddatecellhtml: function(date, colspan, otherattrs) {
		var view = this.view;

		return '' +
			'<th class="fc-day-header ' + view.widgetheaderclass + ' fc-' + dayids[date.day()] + '"' +
				(this.rowcnt == 1 ?
					' data-date="' + date.format('yyyy-mm-dd') + '"' :
					'') +
				(colspan > 1 ?
					' colspan="' + colspan + '"' :
					'') +
				(otherattrs ?
					' ' + otherattrs :
					'') +
			'>' +
				htmlescape(date.format(this.colheadformat)) +
			'</th>';
	},


	/* background rendering
	------------------------------------------------------------------------------------------------------------------*/


	renderbgtrhtml: function(row) {
		return '' +
			'<tr>' +
				(this.isrtl ? '' : this.renderbgintrohtml(row)) +
				this.renderbgcellshtml(row) +
				(this.isrtl ? this.renderbgintrohtml(row) : '') +
			'</tr>';
	},


	renderbgintrohtml: function(row) {
		return this.renderintrohtml(); // fall back to generic
	},


	renderbgcellshtml: function(row) {
		var htmls = [];
		var col, date;

		for (col = 0; col < this.colcnt; col++) {
			date = this.getcelldate(row, col);
			htmls.push(this.renderbgcellhtml(date));
		}

		return htmls.join('');
	},


	renderbgcellhtml: function(date, otherattrs) {
		var view = this.view;
		var classes = this.getdayclasses(date);

		classes.unshift('fc-day', view.widgetcontentclass);

		return '<td class="' + classes.join(' ') + '"' +
			'  id="' + date.format() + '" data-date="' + date.format('yyyy-mm-dd') + '"' + // if date has a time, won't format it
			(otherattrs ?
				' ' + otherattrs :
				'') +
			'></td>';
	},


	/* generic
	------------------------------------------------------------------------------------------------------------------*/


	// generates the default html intro for any row. user classes should override
	renderintrohtml: function() {
	},


	// todo: a generic method for dealing with <tr>, rtl, intro
	// when increment internalapiversion
	// wraptr (scheduler)


	/* utils
	------------------------------------------------------------------------------------------------------------------*/


	// applies the generic "intro" and "outro" html to the given cells.
	// intro means the leftmost cell when the calendar is ltr and the rightmost cell when rtl. vice-versa for outro.
	bookendcells: function(trel) {
		var introhtml = this.renderintrohtml();

		if (introhtml) {
			if (this.isrtl) {
				trel.append(introhtml);
			}
			else {
				trel.prepend(introhtml);
			}
		}
	}

};

;;

/* a component that renders a grid of whole-days that runs horizontally. there can be multiple rows, one per week.
----------------------------------------------------------------------------------------------------------------------*/

var daygrid = fc.daygrid = grid.extend(daytablemixin, {

	numbersvisible: false, // should render a row for day/week numbers? set by outside view. todo: make internal
	bottomcoordpadding: 0, // hack for extending the hit area for the last row of the coordinate grid

	rowels: null, // set of fake row elements
	cellels: null, // set of whole-day elements comprising the row's background
	helperels: null, // set of cell skeleton elements for rendering the mock event "helper"

	rowcoordcache: null,
	colcoordcache: null,


	// renders the rows and columns into the component's `this.el`, which should already be assigned.
	// isrigid determins whether the individual rows should ignore the contents and be a constant height.
	// relies on the view's colcnt and rowcnt. in the future, this component should probably be self-sufficient.
	renderdates: function(isrigid) {
		var view = this.view;
		var rowcnt = this.rowcnt;
		var colcnt = this.colcnt;
		var html = '';
		var row;
		var col;

		for (row = 0; row < rowcnt; row++) {
			html += this.renderdayrowhtml(row, isrigid);
		}
		this.el.html(html);

		this.rowels = this.el.find('.fc-row');
		this.cellels = this.el.find('.fc-day');

		this.rowcoordcache = new coordcache({
			els: this.rowels,
			isvertical: true
		});
		this.colcoordcache = new coordcache({
			els: this.cellels.slice(0, this.colcnt), // only the first row
			ishorizontal: true
		});

		// trigger dayrender with each cell's element
		for (row = 0; row < rowcnt; row++) {
			for (col = 0; col < colcnt; col++) {
				view.trigger(
					'dayrender',
					null,
					this.getcelldate(row, col),
					this.getcellel(row, col)
				);
			}
		}
	},


	unrenderdates: function() {
		this.removesegpopover();
	},


	renderbusinesshours: function() {
		var events = this.view.calendar.getbusinesshoursevents(true); // wholeday=true
		var segs = this.eventstosegs(events);

		this.renderfill('businesshours', segs, 'bgevent');
	},


	// generates the html for a single row, which is a div that wraps a table.
	// `row` is the row number.
	renderdayrowhtml: function(row, isrigid) {
		var view = this.view;
		var classes = [ 'fc-row', 'fc-week', view.widgetcontentclass ];

		if (isrigid) {
			classes.push('fc-rigid');
		}

		return '' +
			'<div class="' + classes.join(' ') + '">' +
				'<div class="fc-bg">' +
					'<table>' +
						this.renderbgtrhtml(row) +
					'</table>' +
				'</div>' +
				'<div class="fc-content-skeleton">' +
					'<table>' +
						(this.numbersvisible ?
							'<thead>' +
								this.rendernumbertrhtml(row) +
							'</thead>' :
							''
							) +
					'</table>' +
				'</div>' +
			'</div>';
	},


	/* grid number rendering
	------------------------------------------------------------------------------------------------------------------*/


	rendernumbertrhtml: function(row) {
		return '' +
			'<tr>' +
				(this.isrtl ? '' : this.rendernumberintrohtml(row)) +
				this.rendernumbercellshtml(row) +
				(this.isrtl ? this.rendernumberintrohtml(row) : '') +
			'</tr>';
	},


	rendernumberintrohtml: function(row) {
		return this.renderintrohtml();
	},


	rendernumbercellshtml: function(row) {
		var htmls = [];
		var col, date;

		for (col = 0; col < this.colcnt; col++) {
			date = this.getcelldate(row, col);
			htmls.push(this.rendernumbercellhtml(date));
		}

		return htmls.join('');
	},


	// generates the html for the <td>s of the "number" row in the daygrid's content skeleton.
	// the number row will only exist if either day numbers or week numbers are turned on.
	rendernumbercellhtml: function(date) {
		var classes;

		if (!this.view.daynumbersvisible) { // if there are week numbers but not day numbers
			return '<td/>'; //  will create an empty space above events :(
		}

		classes = this.getdayclasses(date);
		classes.unshift('fc-day-number');

		return '' +
			'<td class="' + classes.join(' ') + '" data-date="' + date.format() + '">' +
				date.date() +
			'</td>';
	},


	/* options
	------------------------------------------------------------------------------------------------------------------*/


	// computes a default event time formatting string if `timeformat` is not explicitly defined
	computeeventtimeformat: function() {
		return this.view.opt('extrasmalltimeformat'); // like "6p" or "6:30p"
	},


	// computes a default `displayeventend` value if one is not expliclty defined
	computedisplayeventend: function() {
		return this.colcnt == 1; // we'll likely have space if there's only one day
	},


	/* dates
	------------------------------------------------------------------------------------------------------------------*/


	rangeupdated: function() {
		this.updatedaytable();
	},


	// slices up the given span (unzoned start/end with other misc data) into an array of segments
	spantosegs: function(span) {
		var segs = this.slicerangebyrow(span);
		var i, seg;

		for (i = 0; i < segs.length; i++) {
			seg = segs[i];
			if (this.isrtl) {
				seg.leftcol = this.daysperrow - 1 - seg.lastrowdayindex;
				seg.rightcol = this.daysperrow - 1 - seg.firstrowdayindex;
			}
			else {
				seg.leftcol = seg.firstrowdayindex;
				seg.rightcol = seg.lastrowdayindex;
			}
		}

		return segs;
	},


	/* hit system
	------------------------------------------------------------------------------------------------------------------*/


	preparehits: function() {
		this.colcoordcache.build();
		this.rowcoordcache.build();
		this.rowcoordcache.bottoms[this.rowcnt - 1] += this.bottomcoordpadding; // hack
	},


	releasehits: function() {
		this.colcoordcache.clear();
		this.rowcoordcache.clear();
	},


	queryhit: function(leftoffset, topoffset) {
		var col = this.colcoordcache.gethorizontalindex(leftoffset);
		var row = this.rowcoordcache.getverticalindex(topoffset);

		if (row != null && col != null) {
			return this.getcellhit(row, col);
		}
	},


	gethitspan: function(hit) {
		return this.getcellrange(hit.row, hit.col);
	},


	gethitel: function(hit) {
		return this.getcellel(hit.row, hit.col);
	},


	/* cell system
	------------------------------------------------------------------------------------------------------------------*/
	// fyi: the first column is the leftmost column, regardless of date


	getcellhit: function(row, col) {
		return {
			row: row,
			col: col,
			component: this, // needed unfortunately :(
			left: this.colcoordcache.getleftoffset(col),
			right: this.colcoordcache.getrightoffset(col),
			top: this.rowcoordcache.gettopoffset(row),
			bottom: this.rowcoordcache.getbottomoffset(row)
		};
	},


	getcellel: function(row, col) {
		return this.cellels.eq(row * this.colcnt + col);
	},


	/* event drag visualization
	------------------------------------------------------------------------------------------------------------------*/
	// todo: move to daygrid.event, similar to what we did with grid's drag methods


	// renders a visual indication of an event or external element being dragged.
	// `eventlocation` has zoned start and end (optional)
	renderdrag: function(eventlocation, seg) {

		// always render a highlight underneath
		this.renderhighlight(this.eventtospan(eventlocation));

		// if a segment from the same calendar but another component is being dragged, render a helper event
		if (seg && !seg.el.closest(this.el).length) {

			this.rendereventlocationhelper(eventlocation, seg);
			this.applydragopacity(this.helperels);

			return true; // a helper has been rendered
		}
	},


	// unrenders any visual indication of a hovering event
	unrenderdrag: function() {
		this.unrenderhighlight();
		this.unrenderhelper();
	},


	/* event resize visualization
	------------------------------------------------------------------------------------------------------------------*/


	// renders a visual indication of an event being resized
	rendereventresize: function(eventlocation, seg) {
		this.renderhighlight(this.eventtospan(eventlocation));
		this.rendereventlocationhelper(eventlocation, seg);
	},


	// unrenders a visual indication of an event being resized
	unrendereventresize: function() {
		this.unrenderhighlight();
		this.unrenderhelper();
	},


	/* event helper
	------------------------------------------------------------------------------------------------------------------*/


	// renders a mock "helper" event. `sourceseg` is the associated internal segment object. it can be null.
	renderhelper: function(event, sourceseg) {
		var helpernodes = [];
		var segs = this.eventtosegs(event);
		var rowstructs;

		segs = this.renderfgsegels(segs); // assigns each seg's el and returns a subset of segs that were rendered
		rowstructs = this.rendersegrows(segs);

		// inject each new event skeleton into each associated row
		this.rowels.each(function(row, rownode) {
			var rowel = $(rownode); // the .fc-row
			var skeletonel = $('<div class="fc-helper-skeleton"><table/></div>'); // will be absolutely positioned
			var skeletontop;

			// if there is an original segment, match the top position. otherwise, put it at the row's top level
			if (sourceseg && sourceseg.row === row) {
				skeletontop = sourceseg.el.position().top;
			}
			else {
				skeletontop = rowel.find('.fc-content-skeleton tbody').position().top;
			}

			skeletonel.css('top', skeletontop)
				.find('table')
					.append(rowstructs[row].tbodyel);

			rowel.append(skeletonel);
			helpernodes.push(skeletonel[0]);
		});

		this.helperels = $(helpernodes); // array -> jquery set
	},


	// unrenders any visual indication of a mock helper event
	unrenderhelper: function() {
		if (this.helperels) {
			this.helperels.remove();
			this.helperels = null;
		}
	},


	/* fill system (highlight, background events, business hours)
	------------------------------------------------------------------------------------------------------------------*/


	fillsegtag: 'td', // override the default tag name


	// renders a set of rectangles over the given segments of days.
	// only returns segments that successfully rendered.
	renderfill: function(type, segs, classname) {
		var nodes = [];
		var i, seg;
		var skeletonel;

		segs = this.renderfillsegels(type, segs); // assignes `.el` to each seg. returns successfully rendered segs

		for (i = 0; i < segs.length; i++) {
			seg = segs[i];
			skeletonel = this.renderfillrow(type, seg, classname);
			this.rowels.eq(seg.row).append(skeletonel);
			nodes.push(skeletonel[0]);
		}

		this.elsbyfill[type] = $(nodes);

		return segs;
	},


	// generates the html needed for one row of a fill. requires the seg's el to be rendered.
	renderfillrow: function(type, seg, classname) {
		var colcnt = this.colcnt;
		var startcol = seg.leftcol;
		var endcol = seg.rightcol + 1;
		var skeletonel;
		var trel;

		classname = classname || type.tolowercase();

		skeletonel = $(
			'<div class="fc-' + classname + '-skeleton">' +
				'<table><tr/></table>' +
			'</div>'
		);
		trel = skeletonel.find('tr');

		if (startcol > 0) {
			trel.append('<td colspan="' + startcol + '"/>');
		}

		trel.append(
			seg.el.attr('colspan', endcol - startcol)
		);

		if (endcol < colcnt) {
			trel.append('<td colspan="' + (colcnt - endcol) + '"/>');
		}

		this.bookendcells(trel);

		return skeletonel;
	}

});

;;

/* event-rendering methods for the daygrid class
----------------------------------------------------------------------------------------------------------------------*/

daygrid.mixin({

	rowstructs: null, // an array of objects, each holding information about a row's foreground event-rendering


	// unrenders all events currently rendered on the grid
	unrenderevents: function() {
		this.removesegpopover(); // removes the "more.." events popover
		grid.prototype.unrenderevents.apply(this, arguments); // calls the super-method
	},


	// retrieves all rendered segment objects currently rendered on the grid
	geteventsegs: function() {
		return grid.prototype.geteventsegs.call(this) // get the segments from the super-method
			.concat(this.popoversegs || []); // append the segments from the "more..." popover
	},


	// renders the given background event segments onto the grid
	renderbgsegs: function(segs) {

		// don't render timed background events
		var alldaysegs = $.grep(segs, function(seg) {
			return seg.event.allday;
		});

		return grid.prototype.renderbgsegs.call(this, alldaysegs); // call the super-method
	},


	// renders the given foreground event segments onto the grid
	renderfgsegs: function(segs) {
		var rowstructs;

		// render an `.el` on each seg
		// returns a subset of the segs. segs that were actually rendered
		segs = this.renderfgsegels(segs);

		rowstructs = this.rowstructs = this.rendersegrows(segs);

		// append to each row's content skeleton
		this.rowels.each(function(i, rownode) {
			$(rownode).find('.fc-content-skeleton > table').append(
				rowstructs[i].tbodyel
			);
		});

		return segs; // return only the segs that were actually rendered
	},


	// unrenders all currently rendered foreground event segments
	unrenderfgsegs: function() {
		var rowstructs = this.rowstructs || [];
		var rowstruct;

		while ((rowstruct = rowstructs.pop())) {
			rowstruct.tbodyel.remove();
		}

		this.rowstructs = null;
	},


	// uses the given events array to generate <tbody> elements that should be appended to each row's content skeleton.
	// returns an array of rowstruct objects (see the bottom of `rendersegrow`).
	// precondition: each segment shoud already have a rendered and assigned `.el`
	rendersegrows: function(segs) {
		var rowstructs = [];
		var segrows;
		var row;

		segrows = this.groupsegrows(segs); // group into nested arrays

		// iterate each row of segment groupings
		for (row = 0; row < segrows.length; row++) {
			rowstructs.push(
				this.rendersegrow(row, segrows[row])
			);
		}

		return rowstructs;
	},


	// builds the html to be used for the default element for an individual segment
	fgseghtml: function(seg, disableresizing) {
		var view = this.view;
		var event = seg.event;
		var isdraggable = view.iseventdraggable(event);
		var isresizablefromstart = !disableresizing && event.allday &&
			seg.isstart && view.iseventresizablefromstart(event);
		var isresizablefromend = !disableresizing && event.allday &&
			seg.isend && view.iseventresizablefromend(event);
		var classes = this.getsegclasses(seg, isdraggable, isresizablefromstart || isresizablefromend);
		var skincss = csstostr(this.getsegskincss(seg));
		var timehtml = '';
		var timetext;
		var titlehtml;

		classes.unshift('fc-day-grid-event', 'fc-h-event');

		// only display a timed events time if it is the starting segment
		if (seg.isstart) {
			timetext = this.geteventtimetext(event);
			if (timetext) {
				timehtml = '<span class="fc-time">' + htmlescape(timetext) + '</span>';
			}
		}

		titlehtml =
			'<span class="fc-title">' +
				(htmlescape(event.title || '') || '&nbsp;') + // we always want one line of height
			'</span>';
		
		return '<a class="' + classes.join(' ') + '"' +
				(event.url ?
					' href="' + htmlescape(event.url) + '"' :
					''
					) +
				(skincss ?
					' style="' + skincss + '"' :
					''
					) +
			'>' +
				'<div class="fc-content">' +
					(this.isrtl ?
						titlehtml + ' ' + timehtml : // put a natural space in between
						timehtml + ' ' + titlehtml   //
						) +
				'</div>' +
				(isresizablefromstart ?
					'<div class="fc-resizer fc-start-resizer" />' :
					''
					) +
				(isresizablefromend ?
					'<div class="fc-resizer fc-end-resizer" />' :
					''
					) +
			'</a>';
	},


	// given a row # and an array of segments all in the same row, render a <tbody> element, a skeleton that contains
	// the segments. returns object with a bunch of internal data about how the render was calculated.
	// note: modifies rowsegs
	rendersegrow: function(row, rowsegs) {
		var colcnt = this.colcnt;
		var seglevels = this.buildseglevels(rowsegs); // group into sub-arrays of levels
		var levelcnt = math.max(1, seglevels.length); // ensure at least one level
		var tbody = $('<tbody/>');
		var segmatrix = []; // lookup for which segments are rendered into which level+col cells
		var cellmatrix = []; // lookup for all <td> elements of the level+col matrix
		var lonecellmatrix = []; // lookup for <td> elements that only take up a single column
		var i, levelsegs;
		var col;
		var tr;
		var j, seg;
		var td;

		// populates empty cells from the current column (`col`) to `endcol`
		function emptycellsuntil(endcol) {
			while (col < endcol) {
				// try to grab a cell from the level above and extend its rowspan. otherwise, create a fresh cell
				td = (lonecellmatrix[i - 1] || [])[col];
				if (td) {
					td.attr(
						'rowspan',
						parseint(td.attr('rowspan') || 1, 10) + 1
					);
				}
				else {
					td = $('<td/>');
					tr.append(td);
				}
				cellmatrix[i][col] = td;
				lonecellmatrix[i][col] = td;
				col++;
			}
		}

		for (i = 0; i < levelcnt; i++) { // iterate through all levels
			levelsegs = seglevels[i];
			col = 0;
			tr = $('<tr/>');

			segmatrix.push([]);
			cellmatrix.push([]);
			lonecellmatrix.push([]);

			// levelcnt might be 1 even though there are no actual levels. protect against this.
			// this single empty row is useful for styling.
			if (levelsegs) {
				for (j = 0; j < levelsegs.length; j++) { // iterate through segments in level
					seg = levelsegs[j];

					emptycellsuntil(seg.leftcol);

					// create a container that occupies or more columns. append the event element.
					td = $('<td class="fc-event-container"/>').append(seg.el);
					if (seg.leftcol != seg.rightcol) {
						td.attr('colspan', seg.rightcol - seg.leftcol + 1);
					}
					else { // a single-column segment
						lonecellmatrix[i][col] = td;
					}

					while (col <= seg.rightcol) {
						cellmatrix[i][col] = td;
						segmatrix[i][col] = seg;
						col++;
					}

					tr.append(td);
				}
			}

			emptycellsuntil(colcnt); // finish off the row
			this.bookendcells(tr);
			tbody.append(tr);
		}

		return { // a "rowstruct"
			row: row, // the row number
			tbodyel: tbody,
			cellmatrix: cellmatrix,
			segmatrix: segmatrix,
			seglevels: seglevels,
			segs: rowsegs
		};
	},


	// stacks a flat array of segments, which are all assumed to be in the same row, into subarrays of vertical levels.
	// note: modifies segs
	buildseglevels: function(segs) {
		var levels = [];
		var i, seg;
		var j;

		// give preference to elements with certain criteria, so they have
		// a chance to be closer to the top.
		this.sorteventsegs(segs);
		
		for (i = 0; i < segs.length; i++) {
			seg = segs[i];

			// loop through levels, starting with the topmost, until the segment doesn't collide with other segments
			for (j = 0; j < levels.length; j++) {
				if (!isdaysegcollision(seg, levels[j])) {
					break;
				}
			}
			// `j` now holds the desired subrow index
			seg.level = j;

			// create new level array if needed and append segment
			(levels[j] || (levels[j] = [])).push(seg);
		}

		// order segments left-to-right. very important if calendar is rtl
		for (j = 0; j < levels.length; j++) {
			levels[j].sort(comparedaysegcols);
		}

		return levels;
	},


	// given a flat array of segments, return an array of sub-arrays, grouped by each segment's row
	groupsegrows: function(segs) {
		var segrows = [];
		var i;

		for (i = 0; i < this.rowcnt; i++) {
			segrows.push([]);
		}

		for (i = 0; i < segs.length; i++) {
			segrows[segs[i].row].push(segs[i]);
		}

		return segrows;
	}

});


// computes whether two segments' columns collide. they are assumed to be in the same row.
function isdaysegcollision(seg, othersegs) {
	var i, otherseg;

	for (i = 0; i < othersegs.length; i++) {
		otherseg = othersegs[i];

		if (
			otherseg.leftcol <= seg.rightcol &&
			otherseg.rightcol >= seg.leftcol
		) {
			return true;
		}
	}

	return false;
}


// a cmp function for determining the leftmost event
function comparedaysegcols(a, b) {
	return a.leftcol - b.leftcol;
}

;;

/* methods relate to limiting the number events for a given day on a daygrid
----------------------------------------------------------------------------------------------------------------------*/
// note: all the segs being passed around in here are foreground segs

daygrid.mixin({

	segpopover: null, // the popover that holds events that can't fit in a cell. null when not visible
	popoversegs: null, // an array of segment objects that the segpopover holds. null when not visible


	removesegpopover: function() {
		if (this.segpopover) {
			this.segpopover.hide(); // in handler, will call segpopover's removeelement
		}
	},


	// limits the number of "levels" (vertically stacking layers of events) for each row of the grid.
	// `levellimit` can be false (don't limit), a number, or true (should be computed).
	limitrows: function(levellimit) {
		var rowstructs = this.rowstructs || [];
		var row; // row #
		var rowlevellimit;

		for (row = 0; row < rowstructs.length; row++) {
			this.unlimitrow(row);

			if (!levellimit) {
				rowlevellimit = false;
			}
			else if (typeof levellimit === 'number') {
				rowlevellimit = levellimit;
			}
			else {
				rowlevellimit = this.computerowlevellimit(row);
			}

			if (rowlevellimit !== false) {
				this.limitrow(row, rowlevellimit);
			}
		}
	},


	// computes the number of levels a row will accomodate without going outside its bounds.
	// assumes the row is "rigid" (maintains a constant height regardless of what is inside).
	// `row` is the row number.
	computerowlevellimit: function(row) {
		var rowel = this.rowels.eq(row); // the containing "fake" row div
		var rowheight = rowel.height(); // todo: cache somehow?
		var trels = this.rowstructs[row].tbodyel.children();
		var i, trel;
		var trheight;

		function iterinnerheights(i, childnode) {
			trheight = math.max(trheight, $(childnode).outerheight());
		}

		// reveal one level <tr> at a time and stop when we find one out of bounds
		for (i = 0; i < trels.length; i++) {
			trel = trels.eq(i).removeclass('fc-limited'); // reset to original state (reveal)

			// with rowspans>1 and ie8, trel.outerheight() would return the height of the largest cell,
			// so instead, find the tallest inner content element.
			trheight = 0;
			trel.find('> td > :first-child').each(iterinnerheights);

			if (trel.position().top + trheight > rowheight) {
				return i;
			}
		}

		return false; // should not limit at all
	},


	// limits the given grid row to the maximum number of levels and injects "more" links if necessary.
	// `row` is the row number.
	// `levellimit` is a number for the maximum (inclusive) number of levels allowed.
	limitrow: function(row, levellimit) {
		var _this = this;
		var rowstruct = this.rowstructs[row];
		var morenodes = []; // array of "more" <a> links and <td> dom nodes
		var col = 0; // col #, left-to-right (not chronologically)
		var levelsegs; // array of segment objects in the last allowable level, ordered left-to-right
		var cellmatrix; // a matrix (by level, then column) of all <td> jquery elements in the row
		var limitednodes; // array of temporarily hidden level <tr> and segment <td> dom nodes
		var i, seg;
		var segsbelow; // array of segment objects below `seg` in the current `col`
		var totalsegsbelow; // total number of segments below `seg` in any of the columns `seg` occupies
		var colsegsbelow; // array of segment arrays, below seg, one for each column (offset from segs's first column)
		var td, rowspan;
		var segmorenodes; // array of "more" <td> cells that will stand-in for the current seg's cell
		var j;
		var moretd, morewrap, morelink;

		// iterates through empty level cells and places "more" links inside if need be
		function emptycellsuntil(endcol) { // goes from current `col` to `endcol`
			while (col < endcol) {
				segsbelow = _this.getcellsegs(row, col, levellimit);
				if (segsbelow.length) {
					td = cellmatrix[levellimit - 1][col];
					morelink = _this.rendermorelink(row, col, segsbelow);
					morewrap = $('<div/>').append(morelink);
					td.append(morewrap);
					morenodes.push(morewrap[0]);
				}
				col++;
			}
		}

		if (levellimit && levellimit < rowstruct.seglevels.length) { // is it actually over the limit?
			levelsegs = rowstruct.seglevels[levellimit - 1];
			cellmatrix = rowstruct.cellmatrix;

			limitednodes = rowstruct.tbodyel.children().slice(levellimit) // get level <tr> elements past the limit
				.addclass('fc-limited').get(); // hide elements and get a simple dom-nodes array

			// iterate though segments in the last allowable level
			for (i = 0; i < levelsegs.length; i++) {
				seg = levelsegs[i];
				emptycellsuntil(seg.leftcol); // process empty cells before the segment

				// determine *all* segments below `seg` that occupy the same columns
				colsegsbelow = [];
				totalsegsbelow = 0;
				while (col <= seg.rightcol) {
					segsbelow = this.getcellsegs(row, col, levellimit);
					colsegsbelow.push(segsbelow);
					totalsegsbelow += segsbelow.length;
					col++;
				}

				if (totalsegsbelow) { // do we need to replace this segment with one or many "more" links?
					td = cellmatrix[levellimit - 1][seg.leftcol]; // the segment's parent cell
					rowspan = td.attr('rowspan') || 1;
					segmorenodes = [];

					// make a replacement <td> for each column the segment occupies. will be one for each colspan
					for (j = 0; j < colsegsbelow.length; j++) {
						moretd = $('<td class="fc-more-cell"/>').attr('rowspan', rowspan);
						segsbelow = colsegsbelow[j];
						morelink = this.rendermorelink(
							row,
							seg.leftcol + j,
							[ seg ].concat(segsbelow) // count seg as hidden too
						);
						morewrap = $('<div/>').append(morelink);
						moretd.append(morewrap);
						segmorenodes.push(moretd[0]);
						morenodes.push(moretd[0]);
					}

					td.addclass('fc-limited').after($(segmorenodes)); // hide original <td> and inject replacements
					limitednodes.push(td[0]);
				}
			}

			emptycellsuntil(this.colcnt); // finish off the level
			rowstruct.moreels = $(morenodes); // for easy undoing later
			rowstruct.limitedels = $(limitednodes); // for easy undoing later
		}
	},


	// reveals all levels and removes all "more"-related elements for a grid's row.
	// `row` is a row number.
	unlimitrow: function(row) {
		var rowstruct = this.rowstructs[row];

		if (rowstruct.moreels) {
			rowstruct.moreels.remove();
			rowstruct.moreels = null;
		}

		if (rowstruct.limitedels) {
			rowstruct.limitedels.removeclass('fc-limited');
			rowstruct.limitedels = null;
		}
	},


	// renders an <a> element that represents hidden event element for a cell.
	// responsible for attaching click handler as well.
	rendermorelink: function(row, col, hiddensegs) {
		var _this = this;
		var view = this.view;

		return $('<a class="fc-more"/>')
			.text(
				this.getmorelinktext(hiddensegs.length)
			)
			.on('click', function(ev) {
				var clickoption = view.opt('eventlimitclick');
				var date = _this.getcelldate(row, col);
				var moreel = $(this);
				var dayel = _this.getcellel(row, col);
				var allsegs = _this.getcellsegs(row, col);

				// rescope the segments to be within the cell's date
				var reslicedallsegs = _this.reslicedaysegs(allsegs, date);
				var reslicedhiddensegs = _this.reslicedaysegs(hiddensegs, date);

				if (typeof clickoption === 'function') {
					// the returned value can be an atomic option
					clickoption = view.trigger('eventlimitclick', null, {
						date: date,
						dayel: dayel,
						moreel: moreel,
						segs: reslicedallsegs,
						hiddensegs: reslicedhiddensegs
					}, ev);
				}

				if (clickoption === 'popover') {
					_this.showsegpopover(row, col, moreel, reslicedallsegs);
				}
				else if (typeof clickoption === 'string') { // a view name
					view.calendar.zoomto(date, clickoption);
				}
			});
	},


	// reveals the popover that displays all events within a cell
	showsegpopover: function(row, col, morelink, segs) {
		var _this = this;
		var view = this.view;
		var morewrap = morelink.parent(); // the <div> wrapper around the <a>
		var topel; // the element we want to match the top coordinate of
		var options;

		if (this.rowcnt == 1) {
			topel = view.el; // will cause the popover to cover any sort of header
		}
		else {
			topel = this.rowels.eq(row); // will align with top of row
		}

		options = {
			classname: 'fc-more-popover',
			content: this.rendersegpopovercontent(row, col, segs),
			parentel: this.el,
			top: topel.offset().top,
			autohide: true, // when the user clicks elsewhere, hide the popover
			viewportconstrain: view.opt('popoverviewportconstrain'),
			hide: function() {
				// kill everything when the popover is hidden
				_this.segpopover.removeelement();
				_this.segpopover = null;
				_this.popoversegs = null;
			}
		};

		// determine horizontal coordinate.
		// we use the morewrap instead of the <td> to avoid border confusion.
		if (this.isrtl) {
			options.right = morewrap.offset().left + morewrap.outerwidth() + 1; // +1 to be over cell border
		}
		else {
			options.left = morewrap.offset().left - 1; // -1 to be over cell border
		}

		this.segpopover = new popover(options);
		this.segpopover.show();
	},


	// builds the inner dom contents of the segment popover
	rendersegpopovercontent: function(row, col, segs) {
		var view = this.view;
		var istheme = view.opt('theme');
		var title = this.getcelldate(row, col).format(view.opt('daypopoverformat'));
		var content = $(
			'<div class="fc-header ' + view.widgetheaderclass + '">' +
				'<span class="fc-close ' +
					(istheme ? 'ui-icon ui-icon-closethick' : 'fc-icon fc-icon-x') +
				'"></span>' +
				'<span class="fc-title">' +
					htmlescape(title) +
				'</span>' +
				'<div class="fc-clear"/>' +
			'</div>' +
			'<div class="fc-body ' + view.widgetcontentclass + '">' +
				'<div class="fc-event-container"></div>' +
			'</div>'
		);
		var segcontainer = content.find('.fc-event-container');
		var i;

		// render each seg's `el` and only return the visible segs
		segs = this.renderfgsegels(segs, true); // disableresizing=true
		this.popoversegs = segs;

		for (i = 0; i < segs.length; i++) {

			// because segments in the popover are not part of a grid coordinate system, provide a hint to any
			// grids that want to do drag-n-drop about which cell it came from
			this.preparehits();
			segs[i].hit = this.getcellhit(row, col);
			this.releasehits();

			segcontainer.append(segs[i].el);
		}

		return content;
	},


	// given the events within an array of segment objects, reslice them to be in a single day
	reslicedaysegs: function(segs, daydate) {

		// build an array of the original events
		var events = $.map(segs, function(seg) {
			return seg.event;
		});

		var daystart = daydate.clone();
		var dayend = daystart.clone().add(1, 'days');
		var dayrange = { start: daystart, end: dayend };

		// slice the events with a custom slicing function
		segs = this.eventstosegs(
			events,
			function(range) {
				var seg = intersectranges(range, dayrange); // undefind if no intersection
				return seg ? [ seg ] : []; // must return an array of segments
			}
		);

		// force an order because eventstosegs doesn't guarantee one
		this.sorteventsegs(segs);

		return segs;
	},


	// generates the text that should be inside a "more" link, given the number of events it represents
	getmorelinktext: function(num) {
		var opt = this.view.opt('eventlimittext');

		if (typeof opt === 'function') {
			return opt(num);
		}
		else {
			return '+' + num + ' ' + opt;
		}
	},


	// returns segments within a given cell.
	// if `startlevel` is specified, returns only events including and below that level. otherwise returns all segs.
	getcellsegs: function(row, col, startlevel) {
		var segmatrix = this.rowstructs[row].segmatrix;
		var level = startlevel || 0;
		var segs = [];
		var seg;

		while (level < segmatrix.length) {
			seg = segmatrix[level][col];
			if (seg) {
				segs.push(seg);
			}
			level++;
		}

		return segs;
	}

});

;;

/* a component that renders one or more columns of vertical time slots
----------------------------------------------------------------------------------------------------------------------*/
// we mixin daytable, even though there is only a single row of days

var timegrid = fc.timegrid = grid.extend(daytablemixin, {

	slotduration: null, // duration of a "slot", a distinct time segment on given day, visualized by lines
	snapduration: null, // granularity of time for dragging and selecting
	snapsperslot: null,
	mintime: null, // duration object that denotes the first visible time of any given day
	maxtime: null, // duration object that denotes the exclusive visible end time of any given day
	labelformat: null, // formatting string for times running along vertical axis
	labelinterval: null, // duration of how often a label should be displayed for a slot

	colels: null, // cells elements in the day-row background
	slatels: null, // elements running horizontally across all columns
	nowindicatorels: null,

	colcoordcache: null,
	slatcoordcache: null,


	constructor: function() {
		grid.apply(this, arguments); // call the super-constructor

		this.processoptions();
	},


	// renders the time grid into `this.el`, which should already be assigned.
	// relies on the view's colcnt. in the future, this component should probably be self-sufficient.
	renderdates: function() {
		this.el.html(this.renderhtml());
		this.colels = this.el.find('.fc-day');
		this.slatels = this.el.find('.fc-slats tr');

		this.colcoordcache = new coordcache({
			els: this.colels,
			ishorizontal: true
		});
		this.slatcoordcache = new coordcache({
			els: this.slatels,
			isvertical: true
		});

		this.rendercontentskeleton();
	},


	// renders the basic html skeleton for the grid
	renderhtml: function() {
		return '' +
			'<div class="fc-bg">' +
				'<table>' +
					this.renderbgtrhtml(0) + // row=0
				'</table>' +
			'</div>' +
			'<div class="fc-slats">' +
				'<table>' +
					this.renderslatrowhtml() +
				'</table>' +
			'</div>';
	},


	// generates the html for the horizontal "slats" that run width-wise. has a time axis on a side. depends on rtl.
	renderslatrowhtml: function() {
		var view = this.view;
		var isrtl = this.isrtl;
		var html = '';
		var slottime = moment.duration(+this.mintime); // wish there was .clone() for durations
		var slotdate; // will be on the view's first day, but we only care about its time
		var islabeled;
		var axishtml;

		// calculate the time for each slot
		while (slottime < this.maxtime) {
			slotdate = this.start.clone().time(slottime);
			islabeled = isint(dividedurationbyduration(slottime, this.labelinterval));

			axishtml =
				'<td class="fc-axis fc-time ' + view.widgetcontentclass + '" ' + view.axisstyleattr() + '>' +
					(islabeled ?
						'<span>' + // for matchcellwidths
							htmlescape(slotdate.format(this.labelformat)) +
						'</span>' :
						''
						) +
				'</td>';

			html +=
				'<tr data-time="' + slotdate.format('hh:mm:ss') + '"' +
					(islabeled ? '' : ' class="fc-minor"') +
					'>' +
					(!isrtl ? axishtml : '') +
					'<td class="' + view.widgetcontentclass + '"/>' +
					(isrtl ? axishtml : '') +
				"</tr>";

			slottime.add(this.slotduration);
		}

		return html;
	},


	/* options
	------------------------------------------------------------------------------------------------------------------*/


	// parses various options into properties of this object
	processoptions: function() {
		var view = this.view;
		var slotduration = view.opt('slotduration');
		var snapduration = view.opt('snapduration');
		var input;

		slotduration = moment.duration(slotduration);
		snapduration = snapduration ? moment.duration(snapduration) : slotduration;

		this.slotduration = slotduration;
		this.snapduration = snapduration;
		this.snapsperslot = slotduration / snapduration; // todo: ensure an integer multiple?

		this.minresizeduration = snapduration; // hack

		this.mintime = moment.duration(view.opt('mintime'));
		this.maxtime = moment.duration(view.opt('maxtime'));

		// might be an array value (for timelineview).
		// if so, getting the most granular entry (the last one probably).
		input = view.opt('slotlabelformat');
		if ($.isarray(input)) {
			input = input[input.length - 1];
		}

		this.labelformat =
			input ||
			view.opt('axisformat') || // deprecated
			view.opt('smalltimeformat'); // the computed default

		input = view.opt('slotlabelinterval');
		this.labelinterval = input ?
			moment.duration(input) :
			this.computelabelinterval(slotduration);
	},


	// computes an automatic value for slotlabelinterval
	computelabelinterval: function(slotduration) {
		var i;
		var labelinterval;
		var slotsperlabel;

		// find the smallest stock label interval that results in more than one slots-per-label
		for (i = agenda_stock_sub_durations.length - 1; i >= 0; i--) {
			labelinterval = moment.duration(agenda_stock_sub_durations[i]);
			slotsperlabel = dividedurationbyduration(labelinterval, slotduration);
			if (isint(slotsperlabel) && slotsperlabel > 1) {
				return labelinterval;
			}
		}

		return moment.duration(slotduration); // fall back. clone
	},


	// computes a default event time formatting string if `timeformat` is not explicitly defined
	computeeventtimeformat: function() {
		return this.view.opt('nomeridiemtimeformat'); // like "6:30" (no am/pm)
	},


	// computes a default `displayeventend` value if one is not expliclty defined
	computedisplayeventend: function() {
		return true;
	},


	/* hit system
	------------------------------------------------------------------------------------------------------------------*/


	preparehits: function() {
		this.colcoordcache.build();
		this.slatcoordcache.build();
	},


	releasehits: function() {
		this.colcoordcache.clear();
		// note: don't clear slatcoordcache because we rely on it for computetimetop
	},


	queryhit: function(leftoffset, topoffset) {
		var snapsperslot = this.snapsperslot;
		var colcoordcache = this.colcoordcache;
		var slatcoordcache = this.slatcoordcache;
		var colindex = colcoordcache.gethorizontalindex(leftoffset);
		var slatindex = slatcoordcache.getverticalindex(topoffset);

		if (colindex != null && slatindex != null) {
			var slattop = slatcoordcache.gettopoffset(slatindex);
			var slatheight = slatcoordcache.getheight(slatindex);
			var partial = (topoffset - slattop) / slatheight; // floating point number between 0 and 1
			var localsnapindex = math.floor(partial * snapsperslot); // the snap # relative to start of slat
			var snapindex = slatindex * snapsperslot + localsnapindex;
			var snaptop = slattop + (localsnapindex / snapsperslot) * slatheight;
			var snapbottom = slattop + ((localsnapindex + 1) / snapsperslot) * slatheight;

			return {
				col: colindex,
				snap: snapindex,
				component: this, // needed unfortunately :(
				left: colcoordcache.getleftoffset(colindex),
				right: colcoordcache.getrightoffset(colindex),
				top: snaptop,
				bottom: snapbottom
			};
		}
	},


	gethitspan: function(hit) {
		var start = this.getcelldate(0, hit.col); // row=0
		var time = this.computesnaptime(hit.snap); // pass in the snap-index
		var end;

		start.time(time);
		end = start.clone().add(this.snapduration);

		return { start: start, end: end };
	},


	gethitel: function(hit) {
		return this.colels.eq(hit.col);
	},


	/* dates
	------------------------------------------------------------------------------------------------------------------*/


	rangeupdated: function() {
		this.updatedaytable();
	},


	// given a row number of the grid, representing a "snap", returns a time (duration) from its start-of-day
	computesnaptime: function(snapindex) {
		return moment.duration(this.mintime + this.snapduration * snapindex);
	},


	// slices up the given span (unzoned start/end with other misc data) into an array of segments
	spantosegs: function(span) {
		var segs = this.slicerangebytimes(span);
		var i;

		for (i = 0; i < segs.length; i++) {
			if (this.isrtl) {
				segs[i].col = this.daysperrow - 1 - segs[i].dayindex;
			}
			else {
				segs[i].col = segs[i].dayindex;
			}
		}

		return segs;
	},


	slicerangebytimes: function(range) {
		var segs = [];
		var seg;
		var dayindex;
		var daydate;
		var dayrange;

		for (dayindex = 0; dayindex < this.daysperrow; dayindex++) {
			daydate = this.daydates[dayindex].clone(); // todo: better api for this?
			dayrange = {
				start: daydate.clone().time(this.mintime),
				end: daydate.clone().time(this.maxtime)
			};
			seg = intersectranges(range, dayrange); // both will be ambig timezone
			if (seg) {
				seg.dayindex = dayindex;
				segs.push(seg);
			}
		}

		return segs;
	},


	/* coordinates
	------------------------------------------------------------------------------------------------------------------*/


	updatesize: function(isresize) { // not a standard grid method
		this.slatcoordcache.build();

		if (isresize) {
			this.updatesegverticals(
				[].concat(this.fgsegs || [], this.bgsegs || [], this.businesssegs || [])
			);
		}
	},


	// computes the top coordinate, relative to the bounds of the grid, of the given date.
	// a `startofdaydate` must be given for avoiding ambiguity over how to treat midnight.
	computedatetop: function(date, startofdaydate) {
		return this.computetimetop(
			moment.duration(
				date - startofdaydate.clone().striptime()
			)
		);
	},


	// computes the top coordinate, relative to the bounds of the grid, of the given time (a duration).
	computetimetop: function(time) {
		var len = this.slatels.length;
		var slatcoverage = (time - this.mintime) / this.slotduration; // floating-point value of # of slots covered
		var slatindex;
		var slatremainder;

		// compute a floating-point number for how many slats should be progressed through.
		// from 0 to number of slats (inclusive)
		// constrained because mintime/maxtime might be customized.
		slatcoverage = math.max(0, slatcoverage);
		slatcoverage = math.min(len, slatcoverage);

		// an integer index of the furthest whole slat
		// from 0 to number slats (*exclusive*, so len-1)
		slatindex = math.floor(slatcoverage);
		slatindex = math.min(slatindex, len - 1);

		// how much further through the slatindex slat (from 0.0-1.0) must be covered in addition.
		// could be 1.0 if slatcoverage is covering *all* the slots
		slatremainder = slatcoverage - slatindex;

		return this.slatcoordcache.gettopposition(slatindex) +
			this.slatcoordcache.getheight(slatindex) * slatremainder;
	},



	/* event drag visualization
	------------------------------------------------------------------------------------------------------------------*/


	// renders a visual indication of an event being dragged over the specified date(s).
	// a returned value of `true` signals that a mock "helper" event has been rendered.
	renderdrag: function(eventlocation, seg) {

		if (seg) { // if there is event information for this drag, render a helper event
			this.rendereventlocationhelper(eventlocation, seg);

			for (var i = 0; i < this.helpersegs.length; i++) {
				this.applydragopacity(this.helpersegs[i].el);
			}

			return true; // signal that a helper has been rendered
		}
		else {
			// otherwise, just render a highlight
			this.renderhighlight(this.eventtospan(eventlocation));
		}
	},


	// unrenders any visual indication of an event being dragged
	unrenderdrag: function() {
		this.unrenderhelper();
		this.unrenderhighlight();
	},


	/* event resize visualization
	------------------------------------------------------------------------------------------------------------------*/


	// renders a visual indication of an event being resized
	rendereventresize: function(eventlocation, seg) {
		this.rendereventlocationhelper(eventlocation, seg);
	},


	// unrenders any visual indication of an event being resized
	unrendereventresize: function() {
		this.unrenderhelper();
	},


	/* event helper
	------------------------------------------------------------------------------------------------------------------*/


	// renders a mock "helper" event. `sourceseg` is the original segment object and might be null (an external drag)
	renderhelper: function(event, sourceseg) {
		this.renderhelpersegs(this.eventtosegs(event), sourceseg);
	},


	// unrenders any mock helper event
	unrenderhelper: function() {
		this.unrenderhelpersegs();
	},


	/* business hours
	------------------------------------------------------------------------------------------------------------------*/


	renderbusinesshours: function() {
		var events = this.view.calendar.getbusinesshoursevents();
		var segs = this.eventstosegs(events);

		this.renderbusinesssegs(segs);
	},


	unrenderbusinesshours: function() {
		this.unrenderbusinesssegs();
	},


	/* now indicator
	------------------------------------------------------------------------------------------------------------------*/


	getnowindicatorunit: function() {
		return 'minute'; // will refresh on the minute
	},


	rendernowindicator: function(date) {
		// seg system might be overkill, but it handles scenario where line needs to be rendered
		//  more than once because of columns with the same date (resources columns for example)
		var segs = this.spantosegs({ start: date, end: date });
		var top = this.computedatetop(date, date);
		var nodes = [];
		var i;

		// render lines within the columns
		for (i = 0; i < segs.length; i++) {
			nodes.push($('<div class="fc-now-indicator fc-now-indicator-line"></div>')
				.css('top', top)
				.appendto(this.colcontainerels.eq(segs[i].col))[0]);
		}

		// render an arrow over the axis
		if (segs.length > 0) { // is the current time in view?
			nodes.push($('<div class="fc-now-indicator fc-now-indicator-arrow"></div>')
				.css('top', top)
				.appendto(this.el.find('.fc-content-skeleton'))[0]);
		}

		this.nowindicatorels = $(nodes);
	},


	unrendernowindicator: function() {
		if (this.nowindicatorels) {
			this.nowindicatorels.remove();
			this.nowindicatorels = null;
		}
	},


	/* selection
	------------------------------------------------------------------------------------------------------------------*/


	// renders a visual indication of a selection. overrides the default, which was to simply render a highlight.
	renderselection: function(span) {
		if (this.view.opt('selecthelper')) { // this setting signals that a mock helper event should be rendered

			// normally acceps an eventlocation, span has a start/end, which is good enough
			this.rendereventlocationhelper(span);
		}
		else {
			this.renderhighlight(span);
		}
	},


	// unrenders any visual indication of a selection
	unrenderselection: function() {
		this.unrenderhelper();
		this.unrenderhighlight();
	},


	/* highlight
	------------------------------------------------------------------------------------------------------------------*/


	renderhighlight: function(span) {
		this.renderhighlightsegs(this.spantosegs(span));
	},


	unrenderhighlight: function() {
		this.unrenderhighlightsegs();
	}

});

;;

/* methods for rendering segments, pieces of content that live on the view
 ( this file is no longer just for events )
----------------------------------------------------------------------------------------------------------------------*/

timegrid.mixin({

	colcontainerels: null, // containers for each column

	// inner-containers for each column where different types of segs live
	fgcontainerels: null,
	bgcontainerels: null,
	helpercontainerels: null,
	highlightcontainerels: null,
	businesscontainerels: null,

	// arrays of different types of displayed segments
	fgsegs: null,
	bgsegs: null,
	helpersegs: null,
	highlightsegs: null,
	businesssegs: null,


	// renders the dom that the view's content will live in
	rendercontentskeleton: function() {
		var cellhtml = '';
		var i;
		var skeletonel;

		for (i = 0; i < this.colcnt; i++) {
			cellhtml +=
				'<td>' +
					'<div class="fc-content-col">' +
						'<div class="fc-event-container fc-helper-container"></div>' +
						'<div class="fc-event-container"></div>' +
						'<div class="fc-highlight-container"></div>' +
						'<div class="fc-bgevent-container"></div>' +
						'<div class="fc-business-container"></div>' +
					'</div>' +
				'</td>';
		}

		skeletonel = $(
			'<div class="fc-content-skeleton">' +
				'<table>' +
					'<tr>' + cellhtml + '</tr>' +
				'</table>' +
			'</div>'
		);

		this.colcontainerels = skeletonel.find('.fc-content-col');
		this.helpercontainerels = skeletonel.find('.fc-helper-container');
		this.fgcontainerels = skeletonel.find('.fc-event-container:not(.fc-helper-container)');
		this.bgcontainerels = skeletonel.find('.fc-bgevent-container');
		this.highlightcontainerels = skeletonel.find('.fc-highlight-container');
		this.businesscontainerels = skeletonel.find('.fc-business-container');

		this.bookendcells(skeletonel.find('tr')); // todo: do this on string level
		this.el.append(skeletonel);
	},


	/* foreground events
	------------------------------------------------------------------------------------------------------------------*/


	renderfgsegs: function(segs) {
		segs = this.renderfgsegsintocontainers(segs, this.fgcontainerels);
		this.fgsegs = segs;
		return segs; // needed for grid::renderevents
	},


	unrenderfgsegs: function() {
		this.unrendernamedsegs('fgsegs');
	},


	/* foreground helper events
	------------------------------------------------------------------------------------------------------------------*/


	renderhelpersegs: function(segs, sourceseg) {
		var i, seg;
		var sourceel;

		segs = this.renderfgsegsintocontainers(segs, this.helpercontainerels);

		// try to make the segment that is in the same row as sourceseg look the same
		for (i = 0; i < segs.length; i++) {
			seg = segs[i];
			if (sourceseg && sourceseg.col === seg.col) {
				sourceel = sourceseg.el;
				seg.el.css({
					left: sourceel.css('left'),
					right: sourceel.css('right'),
					'margin-left': sourceel.css('margin-left'),
					'margin-right': sourceel.css('margin-right')
				});
			}
		}

		this.helpersegs = segs;
	},


	unrenderhelpersegs: function() {
		this.unrendernamedsegs('helpersegs');
	},


	/* background events
	------------------------------------------------------------------------------------------------------------------*/


	renderbgsegs: function(segs) {
		segs = this.renderfillsegels('bgevent', segs); // todo: old fill system
		this.updatesegverticals(segs);
		this.attachsegsbycol(this.groupsegsbycol(segs), this.bgcontainerels);
		this.bgsegs = segs;
		return segs; // needed for grid::renderevents
	},


	unrenderbgsegs: function() {
		this.unrendernamedsegs('bgsegs');
	},


	/* highlight
	------------------------------------------------------------------------------------------------------------------*/


	renderhighlightsegs: function(segs) {
		segs = this.renderfillsegels('highlight', segs); // todo: old fill system
		this.updatesegverticals(segs);
		this.attachsegsbycol(this.groupsegsbycol(segs), this.highlightcontainerels);
		this.highlightsegs = segs;
	},


	unrenderhighlightsegs: function() {
		this.unrendernamedsegs('highlightsegs');
	},


	/* business hours
	------------------------------------------------------------------------------------------------------------------*/


	renderbusinesssegs: function(segs) {
		segs = this.renderfillsegels('businesshours', segs); // todo: old fill system
		this.updatesegverticals(segs);
		this.attachsegsbycol(this.groupsegsbycol(segs), this.businesscontainerels);
		this.businesssegs = segs;
	},


	unrenderbusinesssegs: function() {
		this.unrendernamedsegs('businesssegs');
	},


	/* seg rendering utils
	------------------------------------------------------------------------------------------------------------------*/


	// given a flat array of segments, return an array of sub-arrays, grouped by each segment's col
	groupsegsbycol: function(segs) {
		var segsbycol = [];
		var i;

		for (i = 0; i < this.colcnt; i++) {
			segsbycol.push([]);
		}

		for (i = 0; i < segs.length; i++) {
			segsbycol[segs[i].col].push(segs[i]);
		}

		return segsbycol;
	},


	// given segments grouped by column, insert the segments' elements into a parallel array of container
	// elements, each living within a column.
	attachsegsbycol: function(segsbycol, containerels) {
		var col;
		var segs;
		var i;

		for (col = 0; col < this.colcnt; col++) { // iterate each column grouping
			segs = segsbycol[col];

			for (i = 0; i < segs.length; i++) {
				containerels.eq(col).append(segs[i].el);
			}
		}
	},


	// given the name of a property of `this` object, assumed to be an array of segments,
	// loops through each segment and removes from dom. will null-out the property afterwards.
	unrendernamedsegs: function(propname) {
		var segs = this[propname];
		var i;

		if (segs) {
			for (i = 0; i < segs.length; i++) {
				segs[i].el.remove();
			}
			this[propname] = null;
		}
	},



	/* foreground event rendering utils
	------------------------------------------------------------------------------------------------------------------*/


	// given an array of foreground segments, render a dom element for each, computes position,
	// and attaches to the column inner-container elements.
	renderfgsegsintocontainers: function(segs, containerels) {
		var segsbycol;
		var col;

		segs = this.renderfgsegels(segs); // will call fgseghtml
		segsbycol = this.groupsegsbycol(segs);

		for (col = 0; col < this.colcnt; col++) {
			this.updatefgsegcoords(segsbycol[col]);
		}

		this.attachsegsbycol(segsbycol, containerels);

		return segs;
	},


	// renders the html for a single event segment's default rendering
	fgseghtml: function(seg, disableresizing) {
		var view = this.view;
		var event = seg.event;
		var isdraggable = view.iseventdraggable(event);
		var isresizablefromstart = !disableresizing && seg.isstart && view.iseventresizablefromstart(event);
		var isresizablefromend = !disableresizing && seg.isend && view.iseventresizablefromend(event);
		var classes = this.getsegclasses(seg, isdraggable, isresizablefromstart || isresizablefromend);
		var skincss = csstostr(this.getsegskincss(seg));
		var timetext;
		var fulltimetext; // more verbose time text. for the print stylesheet
		var starttimetext; // just the start time text

		classes.unshift('fc-time-grid-event', 'fc-v-event');

		if (view.ismultidayevent(event)) { // if the event appears to span more than one day...
			// don't display time text on segments that run entirely through a day.
			// that would appear as midnight-midnight and would look dumb.
			// otherwise, display the time text for the *segment's* times (like 6pm-midnight or midnight-10am)
			if (seg.isstart || seg.isend) {
				timetext = this.geteventtimetext(seg);
				fulltimetext = this.geteventtimetext(seg, 'lt');
				starttimetext = this.geteventtimetext(seg, null, false); // displayend=false
			}
		} else {
			// display the normal time text for the *event's* times
			timetext = this.geteventtimetext(event);
			fulltimetext = this.geteventtimetext(event, 'lt');
			starttimetext = this.geteventtimetext(event, null, false); // displayend=false
		}

		return '<a class="' + classes.join(' ') + '"' +
			(event.url ?
				' href="' + htmlescape(event.url) + '"' :
				''
				) +
			(skincss ?
				' style="' + skincss + '"' :
				''
				) +
			'>' +
				'<div class="fc-content">' +
					(timetext ?
						'<div class="fc-time"' +
						' data-start="' + htmlescape(starttimetext) + '"' +
						' data-full="' + htmlescape(fulltimetext) + '"' +
						'>' +
							'<span>' + htmlescape(timetext) + '</span>' +
						'</div>' :
						''
						) +
					(event.title ?
						'<div class="fc-title">' +
							htmlescape(event.title) +
						'</div>' :
						''
						) +
				'</div>' +
				'<div class="fc-bg"/>' +
				/* todo: write css for this
				(isresizablefromstart ?
					'<div class="fc-resizer fc-start-resizer" />' :
					''
					) +
				*/
				(isresizablefromend ?
					'<div class="fc-resizer fc-end-resizer" />' :
					''
					) +
			'</a>';
	},


	/* seg position utils
	------------------------------------------------------------------------------------------------------------------*/


	// refreshes the css top/bottom coordinates for each segment element.
	// works when called after initial render, after a window resize/zoom for example.
	updatesegverticals: function(segs) {
		this.computesegverticals(segs);
		this.assignsegverticals(segs);
	},


	// for each segment in an array, computes and assigns its top and bottom properties
	computesegverticals: function(segs) {
		var i, seg;

		for (i = 0; i < segs.length; i++) {
			seg = segs[i];
			seg.top = this.computedatetop(seg.start, seg.start);
			seg.bottom = this.computedatetop(seg.end, seg.start);
		}
	},


	// given segments that already have their top/bottom properties computed, applies those values to
	// the segments' elements.
	assignsegverticals: function(segs) {
		var i, seg;

		for (i = 0; i < segs.length; i++) {
			seg = segs[i];
			seg.el.css(this.generatesegverticalcss(seg));
		}
	},


	// generates an object with css properties for the top/bottom coordinates of a segment element
	generatesegverticalcss: function(seg) {
		return {
			top: seg.top,
			bottom: -seg.bottom // flipped because needs to be space beyond bottom edge of event container
		};
	},


	/* foreground event positioning utils
	------------------------------------------------------------------------------------------------------------------*/


	// given segments that are assumed to all live in the *same column*,
	// compute their verical/horizontal coordinates and assign to their elements.
	updatefgsegcoords: function(segs) {
		this.computesegverticals(segs); // horizontals relies on this
		this.computefgseghorizontals(segs); // compute horizontal coordinates, z-index's, and reorder the array
		this.assignsegverticals(segs);
		this.assignfgseghorizontals(segs);
	},


	// given an array of segments that are all in the same column, sets the backwardcoord and forwardcoord on each.
	// note: also reorders the given array by date!
	computefgseghorizontals: function(segs) {
		var levels;
		var level0;
		var i;

		this.sorteventsegs(segs); // order by certain criteria
		levels = buildslotseglevels(segs);
		computeforwardslotsegs(levels);

		if ((level0 = levels[0])) {

			for (i = 0; i < level0.length; i++) {
				computeslotsegpressures(level0[i]);
			}

			for (i = 0; i < level0.length; i++) {
				this.computefgsegforwardback(level0[i], 0, 0);
			}
		}
	},


	// calculate seg.forwardcoord and seg.backwardcoord for the segment, where both values range
	// from 0 to 1. if the calendar is left-to-right, the seg.backwardcoord maps to "left" and
	// seg.forwardcoord maps to "right" (via percentage). vice-versa if the calendar is right-to-left.
	//
	// the segment might be part of a "series", which means consecutive segments with the same pressure
	// who's width is unknown until an edge has been hit. `seriesbackwardpressure` is the number of
	// segments behind this one in the current series, and `seriesbackwardcoord` is the starting
	// coordinate of the first segment in the series.
	computefgsegforwardback: function(seg, seriesbackwardpressure, seriesbackwardcoord) {
		var forwardsegs = seg.forwardsegs;
		var i;

		if (seg.forwardcoord === undefined) { // not already computed

			if (!forwardsegs.length) {

				// if there are no forward segments, this segment should butt up against the edge
				seg.forwardcoord = 1;
			}
			else {

				// sort highest pressure first
				this.sortforwardsegs(forwardsegs);

				// this segment's forwardcoord will be calculated from the backwardcoord of the
				// highest-pressure forward segment.
				this.computefgsegforwardback(forwardsegs[0], seriesbackwardpressure + 1, seriesbackwardcoord);
				seg.forwardcoord = forwardsegs[0].backwardcoord;
			}

			// calculate the backwardcoord from the forwardcoord. consider the series
			seg.backwardcoord = seg.forwardcoord -
				(seg.forwardcoord - seriesbackwardcoord) / // available width for series
				(seriesbackwardpressure + 1); // # of segments in the series

			// use this segment's coordinates to computed the coordinates of the less-pressurized
			// forward segments
			for (i=0; i<forwardsegs.length; i++) {
				this.computefgsegforwardback(forwardsegs[i], 0, seg.forwardcoord);
			}
		}
	},


	sortforwardsegs: function(forwardsegs) {
		forwardsegs.sort(proxy(this, 'compareforwardsegs'));
	},


	// a cmp function for determining which forward segment to rely on more when computing coordinates.
	compareforwardsegs: function(seg1, seg2) {
		// put higher-pressure first
		return seg2.forwardpressure - seg1.forwardpressure ||
			// put segments that are closer to initial edge first (and favor ones with no coords yet)
			(seg1.backwardcoord || 0) - (seg2.backwardcoord || 0) ||
			// do normal sorting...
			this.compareeventsegs(seg1, seg2);
	},


	// given foreground event segments that have already had their position coordinates computed,
	// assigns position-related css values to their elements.
	assignfgseghorizontals: function(segs) {
		var i, seg;

		for (i = 0; i < segs.length; i++) {
			seg = segs[i];
			seg.el.css(this.generatefgseghorizontalcss(seg));

			// if the height is short, add a classname for alternate styling
			if (seg.bottom - seg.top < 30) {
				seg.el.addclass('fc-short');
			}
		}
	},


	// generates an object with css properties/values that should be applied to an event segment element.
	// contains important positioning-related properties that should be applied to any event element, customized or not.
	generatefgseghorizontalcss: function(seg) {
		var shouldoverlap = this.view.opt('sloteventoverlap');
		var backwardcoord = seg.backwardcoord; // the left side if ltr. the right side if rtl. floating-point
		var forwardcoord = seg.forwardcoord; // the right side if ltr. the left side if rtl. floating-point
		var props = this.generatesegverticalcss(seg); // get top/bottom first
		var left; // amount of space from left edge, a fraction of the total width
		var right; // amount of space from right edge, a fraction of the total width

		if (shouldoverlap) {
			// double the width, but don't go beyond the maximum forward coordinate (1.0)
			forwardcoord = math.min(1, backwardcoord + (forwardcoord - backwardcoord) * 2);
		}

		if (this.isrtl) {
			left = 1 - forwardcoord;
			right = backwardcoord;
		}
		else {
			left = backwardcoord;
			right = 1 - forwardcoord;
		}

		props.zindex = seg.level + 1; // convert from 0-base to 1-based
		props.left = left * 100 + '%';
		props.right = right * 100 + '%';

		if (shouldoverlap && seg.forwardpressure) {
			// add padding to the edge so that forward stacked events don't cover the resizer's icon
			props[this.isrtl ? 'marginleft' : 'marginright'] = 10 * 2; // 10 is a guesstimate of the icon's width
		}

		return props;
	}

});


// builds an array of segments "levels". the first level will be the leftmost tier of segments if the calendar is
// left-to-right, or the rightmost if the calendar is right-to-left. assumes the segments are already ordered by date.
function buildslotseglevels(segs) {
	var levels = [];
	var i, seg;
	var j;

	for (i=0; i<segs.length; i++) {
		seg = segs[i];

		// go through all the levels and stop on the first level where there are no collisions
		for (j=0; j<levels.length; j++) {
			if (!computeslotsegcollisions(seg, levels[j]).length) {
				break;
			}
		}

		seg.level = j;

		(levels[j] || (levels[j] = [])).push(seg);
	}

	return levels;
}


// for every segment, figure out the other segments that are in subsequent
// levels that also occupy the same vertical space. accumulate in seg.forwardsegs
function computeforwardslotsegs(levels) {
	var i, level;
	var j, seg;
	var k;

	for (i=0; i<levels.length; i++) {
		level = levels[i];

		for (j=0; j<level.length; j++) {
			seg = level[j];

			seg.forwardsegs = [];
			for (k=i+1; k<levels.length; k++) {
				computeslotsegcollisions(seg, levels[k], seg.forwardsegs);
			}
		}
	}
}


// figure out which path forward (via seg.forwardsegs) results in the longest path until
// the furthest edge is reached. the number of segments in this path will be seg.forwardpressure
function computeslotsegpressures(seg) {
	var forwardsegs = seg.forwardsegs;
	var forwardpressure = 0;
	var i, forwardseg;

	if (seg.forwardpressure === undefined) { // not already computed

		for (i=0; i<forwardsegs.length; i++) {
			forwardseg = forwardsegs[i];

			// figure out the child's maximum forward path
			computeslotsegpressures(forwardseg);

			// either use the existing maximum, or use the child's forward pressure
			// plus one (for the forwardseg itself)
			forwardpressure = math.max(
				forwardpressure,
				1 + forwardseg.forwardpressure
			);
		}

		seg.forwardpressure = forwardpressure;
	}
}


// find all the segments in `othersegs` that vertically collide with `seg`.
// append into an optionally-supplied `results` array and return.
function computeslotsegcollisions(seg, othersegs, results) {
	results = results || [];

	for (var i=0; i<othersegs.length; i++) {
		if (isslotsegcollision(seg, othersegs[i])) {
			results.push(othersegs[i]);
		}
	}

	return results;
}


// do these segments occupy the same vertical space?
function isslotsegcollision(seg1, seg2) {
	return seg1.bottom > seg2.top && seg1.top < seg2.bottom;
}

;;

/* an abstract class from which other views inherit from
----------------------------------------------------------------------------------------------------------------------*/

var view = fc.view = class.extend({

	type: null, // subclass' view name (string)
	name: null, // deprecated. use `type` instead
	title: null, // the text that will be displayed in the header's title

	calendar: null, // owner calendar object
	options: null, // hash containing all options. already merged with view-specific-options
	el: null, // the view's containing element. set by calendar

	displaying: null, // a promise representing the state of rendering. null if no render requested
	isskeletonrendered: false,
	iseventsrendered: false,

	// range the view is actually displaying (moments)
	start: null,
	end: null, // exclusive

	// range the view is formally responsible for (moments)
	// may be different from start/end. for example, a month view might have 1st-31st, excluding padded dates
	intervalstart: null,
	intervalend: null, // exclusive
	intervalduration: null,
	intervalunit: null, // name of largest unit being displayed, like "month" or "week"

	isrtl: false,
	isselected: false, // boolean whether a range of time is user-selected or not

	eventorderspecs: null, // criteria for ordering events when they have same date/time

	// subclasses can optionally use a scroll container
	scrollerel: null, // the element that will most likely scroll when content is too tall
	scrolltop: null, // cached vertical scroll value

	// classnames styled by jqui themes
	widgetheaderclass: null,
	widgetcontentclass: null,
	highlightstateclass: null,

	// for date utils, computed from options
	nextdaythreshold: null,
	ishiddendayhash: null,

	// document handlers, bound to `this` object
	documentmousedownproxy: null, // todo: doesn't work with touch

	// now indicator
	isnowindicatorrendered: null,
	initialnowdate: null, // result first getnow call
	initialnowqueriedms: null, // ms time the getnow was called
	nowindicatortimeoutid: null, // for refresh timing of now indicator
	nowindicatorintervalid: null, // "


	constructor: function(calendar, type, options, intervalduration) {

		this.calendar = calendar;
		this.type = this.name = type; // .name is deprecated
		this.options = options;
		this.intervalduration = intervalduration || moment.duration(1, 'day');

		this.nextdaythreshold = moment.duration(this.opt('nextdaythreshold'));
		this.initthemingprops();
		this.inithiddendays();
		this.isrtl = this.opt('isrtl');

		this.eventorderspecs = parsefieldspecs(this.opt('eventorder'));

		this.documentmousedownproxy = proxy(this, 'documentmousedown');

		this.initialize();
	},


	// a good place for subclasses to initialize member variables
	initialize: function() {
		// subclasses can implement
	},


	// retrieves an option with the given name
	opt: function(name) {
		return this.options[name];
	},


	// triggers handlers that are view-related. modifies args before passing to calendar.
	trigger: function(name, thisobj) { // arguments beyond thisobj are passed along
		var calendar = this.calendar;

		return calendar.trigger.apply(
			calendar,
			[name, thisobj || this].concat(
				array.prototype.slice.call(arguments, 2), // arguments beyond thisobj
				[ this ] // always make the last argument a reference to the view. todo: deprecate
			)
		);
	},


	/* dates
	------------------------------------------------------------------------------------------------------------------*/


	// updates all internal dates to center around the given current unzoned date.
	setdate: function(date) {
		this.setrange(this.computerange(date));
	},


	// updates all internal dates for displaying the given unzoned range.
	setrange: function(range) {
		$.extend(this, range); // assigns every property to this object's member variables
		this.updatetitle();
	},


	// given a single current unzoned date, produce information about what range to display.
	// subclasses can override. must return all properties.
	computerange: function(date) {
		var intervalunit = computeintervalunit(this.intervalduration);
		var intervalstart = date.clone().startof(intervalunit);
		var intervalend = intervalstart.clone().add(this.intervalduration);
		var start, end;

		// normalize the range's time-ambiguity
		if (/year|month|week|day/.test(intervalunit)) { // whole-days?
			intervalstart.striptime();
			intervalend.striptime();
		}
		else { // needs to have a time?
			if (!intervalstart.hastime()) {
				intervalstart = this.calendar.time(0); // give 00:00 time
			}
			if (!intervalend.hastime()) {
				intervalend = this.calendar.time(0); // give 00:00 time
			}
		}

		start = intervalstart.clone();
		start = this.skiphiddendays(start);
		end = intervalend.clone();
		end = this.skiphiddendays(end, -1, true); // exclusively move backwards

		return {
			intervalunit: intervalunit,
			intervalstart: intervalstart,
			intervalend: intervalend,
			start: start,
			end: end
		};
	},


	// computes the new date when the user hits the prev button, given the current date
	computeprevdate: function(date) {
		return this.massagecurrentdate(
			date.clone().startof(this.intervalunit).subtract(this.intervalduration), -1
		);
	},


	// computes the new date when the user hits the next button, given the current date
	computenextdate: function(date) {
		return this.massagecurrentdate(
			date.clone().startof(this.intervalunit).add(this.intervalduration)
		);
	},


	// given an arbitrarily calculated current date of the calendar, returns a date that is ensured to be completely
	// visible. `direction` is optional and indicates which direction the current date was being
	// incremented or decremented (1 or -1).
	massagecurrentdate: function(date, direction) {
		if (this.intervalduration.as('days') <= 1) { // if the view displays a single day or smaller
			if (this.ishiddenday(date)) {
				date = this.skiphiddendays(date, direction);
				date.startof('day');
			}
		}

		return date;
	},


	/* title and date formatting
	------------------------------------------------------------------------------------------------------------------*/


	// sets the view's title property to the most updated computed value
	updatetitle: function() {
		this.title = this.computetitle();
	},


	// computes what the title at the top of the calendar should be for this view
	computetitle: function() {
		return this.formatrange(
			{
				// in case intervalstart/end has a time, make sure timezone is correct
				start: this.calendar.applytimezone(this.intervalstart),
				end: this.calendar.applytimezone(this.intervalend)
			},
			this.opt('titleformat') || this.computetitleformat(),
			this.opt('titlerangeseparator')
		);
	},


	// generates the format string that should be used to generate the title for the current date range.
	// attempts to compute the most appropriate format if not explicitly specified with `titleformat`.
	computetitleformat: function() {
		if (this.intervalunit == 'year') {
			return 'yyyy';
		}
		else if (this.intervalunit == 'month') {
			return this.opt('monthyearformat'); // like "september 2014"
		}
		else if (this.intervalduration.as('days') > 1) {
			return 'll'; // multi-day range. shorter, like "sep 9 - 10 2014"
		}
		else {
			return 'll'; // one day. longer, like "september 9 2014"
		}
	},


	// utility for formatting a range. accepts a range object, formatting string, and optional separator.
	// displays all-day ranges naturally, with an inclusive end. takes the current isrtl into account.
	// the timezones of the dates within `range` will be respected.
	formatrange: function(range, formatstr, separator) {
		var end = range.end;

		if (!end.hastime()) { // all-day?
			end = end.clone().subtract(1); // convert to inclusive. last ms of previous day
		}

		return formatrange(range.start, end, formatstr, separator, this.opt('isrtl'));
	},


	/* rendering
	------------------------------------------------------------------------------------------------------------------*/


	// sets the container element that the view should render inside of.
	// does other dom-related initializations.
	setelement: function(el) {
		this.el = el;
		this.bindglobalhandlers();
	},


	// removes the view's container element from the dom, clearing any content beforehand.
	// undoes any other dom-related attachments.
	removeelement: function() {
		this.clear(); // clears all content

		// clean up the skeleton
		if (this.isskeletonrendered) {
			this.unrenderskeleton();
			this.isskeletonrendered = false;
		}

		this.unbindglobalhandlers();

		this.el.remove();

		// note: don't null-out this.el in case the view was destroyed within an api callback.
		// we don't null-out the view's other jquery element references upon destroy,
		//  so we shouldn't kill this.el either.
	},


	// does everything necessary to display the view centered around the given unzoned date.
	// does every type of rendering except rendering events.
	// is asychronous and returns a promise.
	display: function(date) {
		var _this = this;
		var scrollstate = null;

		if (this.displaying) {
			scrollstate = this.queryscroll();
		}

		this.calendar.freezecontentheight();

		return this.clear().then(function() { // clear the content first (async)
			return (
				_this.displaying =
					$.when(_this.displayview(date)) // displayview might return a promise
						.then(function() {
							_this.forcescroll(_this.computeinitialscroll(scrollstate));
							_this.calendar.unfreezecontentheight();
							_this.triggerrender();
						})
			);
		});
	},


	// does everything necessary to clear the content of the view.
	// clears dates and events. does not clear the skeleton.
	// is asychronous and returns a promise.
	clear: function() {
		var _this = this;
		var displaying = this.displaying;

		if (displaying) { // previously displayed, or in the process of being displayed?
			return displaying.then(function() { // wait for the display to finish
				_this.displaying = null;
				_this.clearevents();
				return _this.clearview(); // might return a promise. chain it
			});
		}
		else {
			return $.when(); // an immediately-resolved promise
		}
	},


	// displays the view's non-event content, such as date-related content or anything required by events.
	// renders the view's non-content skeleton if necessary.
	// can be asynchronous and return a promise.
	displayview: function(date) {
		if (!this.isskeletonrendered) {
			this.renderskeleton();
			this.isskeletonrendered = true;
		}
		if (date) {
			this.setdate(date);
		}
		if (this.render) {
			this.render(); // todo: deprecate
		}
		this.renderdates();
		this.updatesize();
		this.renderbusinesshours(); // might need coordinates, so should go after updatesize()
		this.startnowindicator();
	},


	// unrenders the view content that was rendered in displayview.
	// can be asynchronous and return a promise.
	clearview: function() {
		this.unselect();
		this.stopnowindicator();
		this.triggerunrender();
		this.unrenderbusinesshours();
		this.unrenderdates();
		if (this.destroy) {
			this.destroy(); // todo: deprecate
		}
	},


	// renders the basic structure of the view before any content is rendered
	renderskeleton: function() {
		// subclasses should implement
	},


	// unrenders the basic structure of the view
	unrenderskeleton: function() {
		// subclasses should implement
	},


	// renders the view's date-related content.
	// assumes setrange has already been called and the skeleton has already been rendered.
	renderdates: function() {
		// subclasses should implement
	},


	// unrenders the view's date-related content
	unrenderdates: function() {
		// subclasses should override
	},


	// signals that the view's content has been rendered
	triggerrender: function() {
		this.trigger('viewrender', this, this, this.el);
	},


	// signals that the view's content is about to be unrendered
	triggerunrender: function() {
		this.trigger('viewdestroy', this, this, this.el);
	},


	// binds dom handlers to elements that reside outside the view container, such as the document
	bindglobalhandlers: function() {
		$(document).on('mousedown', this.documentmousedownproxy);
	},


	// unbinds dom handlers from elements that reside outside the view container
	unbindglobalhandlers: function() {
		$(document).off('mousedown', this.documentmousedownproxy);
	},


	// initializes internal variables related to theming
	initthemingprops: function() {
		var tm = this.opt('theme') ? 'ui' : 'fc';

		this.widgetheaderclass = tm + '-widget-header';
		this.widgetcontentclass = tm + '-widget-content';
		this.highlightstateclass = tm + '-state-highlight';
	},


	/* business hours
	------------------------------------------------------------------------------------------------------------------*/


	// renders business-hours onto the view. assumes updatesize has already been called.
	renderbusinesshours: function() {
		// subclasses should implement
	},


	// unrenders previously-rendered business-hours
	unrenderbusinesshours: function() {
		// subclasses should implement
	},


	/* now indicator
	------------------------------------------------------------------------------------------------------------------*/


	// immediately render the current time indicator and begins re-rendering it at an interval,
	// which is defined by this.getnowindicatorunit().
	// todo: somehow do this for the current whole day's background too
	startnowindicator: function() {
		var _this = this;
		var unit;
		var update;
		var delay; // ms wait value

		if (this.opt('nowindicator')) {
			unit = this.getnowindicatorunit();
			if (unit) {
				update = proxy(this, 'updatenowindicator'); // bind to `this`

				this.initialnowdate = this.calendar.getnow();
				this.initialnowqueriedms = +new date();
				this.rendernowindicator(this.initialnowdate);
				this.isnowindicatorrendered = true;

				// wait until the beginning of the next interval
				delay = this.initialnowdate.clone().startof(unit).add(1, unit) - this.initialnowdate;
				this.nowindicatortimeoutid = settimeout(function() {
					_this.nowindicatortimeoutid = null;
					update();
					delay = +moment.duration(1, unit);
					delay = math.max(100, delay); // prevent too frequent
					_this.nowindicatorintervalid = setinterval(update, delay); // update every interval
				}, delay);
			}
		}
	},


	// rerenders the now indicator, computing the new current time from the amount of time that has passed
	// since the initial getnow call.
	updatenowindicator: function() {
		if (this.isnowindicatorrendered) {
			this.unrendernowindicator();
			this.rendernowindicator(
				this.initialnowdate.clone().add(new date() - this.initialnowqueriedms) // add ms
			);
		}
	},


	// immediately unrenders the view's current time indicator and stops any re-rendering timers.
	// won't cause side effects if indicator isn't rendered.
	stopnowindicator: function() {
		if (this.isnowindicatorrendered) {

			if (this.nowindicatortimeoutid) {
				cleartimeout(this.nowindicatortimeoutid);
				this.nowindicatortimeoutid = null;
			}
			if (this.nowindicatorintervalid) {
				cleartimeout(this.nowindicatorintervalid);
				this.nowindicatorintervalid = null;
			}

			this.unrendernowindicator();
			this.isnowindicatorrendered = false;
		}
	},


	// returns a string unit, like 'second' or 'minute' that defined how often the current time indicator
	// should be refreshed. if something falsy is returned, no time indicator is rendered at all.
	getnowindicatorunit: function() {
		// subclasses should implement
	},


	// renders a current time indicator at the given datetime
	rendernowindicator: function(date) {
		// subclasses should implement
	},


	// undoes the rendering actions from rendernowindicator
	unrendernowindicator: function() {
		// subclasses should implement
	},


	/* dimensions
	------------------------------------------------------------------------------------------------------------------*/


	// refreshes anything dependant upon sizing of the container element of the grid
	updatesize: function(isresize) {
		var scrollstate;

		if (isresize) {
			scrollstate = this.queryscroll();
		}

		this.updateheight(isresize);
		this.updatewidth(isresize);
		this.updatenowindicator();

		if (isresize) {
			this.setscroll(scrollstate);
		}
	},


	// refreshes the horizontal dimensions of the calendar
	updatewidth: function(isresize) {
		// subclasses should implement
	},


	// refreshes the vertical dimensions of the calendar
	updateheight: function(isresize) {
		var calendar = this.calendar; // we poll the calendar for height information

		this.setheight(
			calendar.getsuggestedviewheight(),
			calendar.isheightauto()
		);
	},


	// updates the vertical dimensions of the calendar to the specified height.
	// if `isauto` is set to true, height becomes merely a suggestion and the view should use its "natural" height.
	setheight: function(height, isauto) {
		// subclasses should implement
	},


	/* scroller
	------------------------------------------------------------------------------------------------------------------*/


	// given the total height of the view, return the number of pixels that should be used for the scroller.
	// utility for subclasses.
	computescrollerheight: function(totalheight) {
		var scrollerel = this.scrollerel;
		var both;
		var otherheight; // cumulative height of everything that is not the scrollerel in the view (header+borders)

		both = this.el.add(scrollerel);

		// fuckin ie8/9/10/11 sometimes returns 0 for dimensions. this weird hack was the only thing that worked
		both.css({
			position: 'relative', // cause a reflow, which will force fresh dimension recalculation
			left: -1 // ensure reflow in case the el was already relative. negative is less likely to cause new scroll
		});
		otherheight = this.el.outerheight() - scrollerel.height(); // grab the dimensions
		both.css({ position: '', left: '' }); // undo hack

		return totalheight - otherheight;
	},


	// computes the initial pre-configured scroll state prior to allowing the user to change it.
	// given the scroll state from the previous rendering. if first time rendering, given null.
	computeinitialscroll: function(previousscrollstate) {
		return 0;
	},


	// retrieves the view's current natural scroll state. can return an arbitrary format.
	queryscroll: function() {
		if (this.scrollerel) {
			return this.scrollerel.scrolltop(); // operates on scrollerel by default
		}
	},


	// sets the view's scroll state. will accept the same format computeinitialscroll and queryscroll produce.
	setscroll: function(scrollstate) {
		if (this.scrollerel) {
			return this.scrollerel.scrolltop(scrollstate); // operates on scrollerel by default
		}
	},


	// sets the scroll state, making sure to overcome any predefined scroll value the browser has in mind
	forcescroll: function(scrollstate) {
		var _this = this;

		this.setscroll(scrollstate);
		settimeout(function() {
			_this.setscroll(scrollstate);
		}, 0);
	},


	/* event elements / segments
	------------------------------------------------------------------------------------------------------------------*/


	// does everything necessary to display the given events onto the current view
	displayevents: function(events) {
		var scrollstate = this.queryscroll();

		this.clearevents();
		this.renderevents(events);
		this.iseventsrendered = true;
		this.setscroll(scrollstate);
		this.triggereventrender();
	},


	// does everything necessary to clear the view's currently-rendered events
	clearevents: function() {
		var scrollstate;

		if (this.iseventsrendered) {

			// todo: optimize: if we know this is part of a displayevents call, don't queryscroll/setscroll
			scrollstate = this.queryscroll();

			this.triggereventunrender();
			if (this.destroyevents) {
				this.destroyevents(); // todo: deprecate
			}
			this.unrenderevents();
			this.setscroll(scrollstate);
			this.iseventsrendered = false;
		}
	},


	// renders the events onto the view.
	renderevents: function(events) {
		// subclasses should implement
	},


	// removes event elements from the view.
	unrenderevents: function() {
		// subclasses should implement
	},


	// signals that all events have been rendered
	triggereventrender: function() {
		this.renderedeventsegeach(function(seg) {
			this.trigger('eventafterrender', seg.event, seg.event, seg.el);
		});
		this.trigger('eventafterallrender');
	},


	// signals that all event elements are about to be removed
	triggereventunrender: function() {
		this.renderedeventsegeach(function(seg) {
			this.trigger('eventdestroy', seg.event, seg.event, seg.el);
		});
	},


	// given an event and the default element used for rendering, returns the element that should actually be used.
	// basically runs events and elements through the eventrender hook.
	resolveeventel: function(event, el) {
		var custom = this.trigger('eventrender', event, event, el);

		if (custom === false) { // means don't render at all
			el = null;
		}
		else if (custom && custom !== true) {
			el = $(custom);
		}

		return el;
	},


	// hides all rendered event segments linked to the given event
	showevent: function(event) {
		this.renderedeventsegeach(function(seg) {
			seg.el.css('visibility', '');
		}, event);
	},


	// shows all rendered event segments linked to the given event
	hideevent: function(event) {
		this.renderedeventsegeach(function(seg) {
			seg.el.css('visibility', 'hidden');
		}, event);
	},


	// iterates through event segments that have been rendered (have an el). goes through all by default.
	// if the optional `event` argument is specified, only iterates through segments linked to that event.
	// the `this` value of the callback function will be the view.
	renderedeventsegeach: function(func, event) {
		var segs = this.geteventsegs();
		var i;

		for (i = 0; i < segs.length; i++) {
			if (!event || segs[i].event._id === event._id) {
				if (segs[i].el) {
					func.call(this, segs[i]);
				}
			}
		}
	},


	// retrieves all the rendered segment objects for the view
	geteventsegs: function() {
		// subclasses must implement
		return [];
	},


	/* event drag-n-drop
	------------------------------------------------------------------------------------------------------------------*/


	// computes if the given event is allowed to be dragged by the user
	iseventdraggable: function(event) {
		var source = event.source || {};

		return firstdefined(
			event.starteditable,
			source.starteditable,
			this.opt('eventstarteditable'),
			event.editable,
			source.editable,
			this.opt('editable')
		);
	},


	// must be called when an event in the view is dropped onto new location.
	// `droplocation` is an object that contains the new zoned start/end/allday values for the event.
	reporteventdrop: function(event, droplocation, largeunit, el, ev) {
		var calendar = this.calendar;
		var mutateresult = calendar.mutateevent(event, droplocation, largeunit);
		var undofunc = function() {
			mutateresult.undo();
			calendar.reporteventchange();
		};

		this.triggereventdrop(event, mutateresult.datedelta, undofunc, el, ev);
		calendar.reporteventchange(); // will rerender events
	},


	// triggers event-drop handlers that have subscribed via the api
	triggereventdrop: function(event, datedelta, undofunc, el, ev) {
		this.trigger('eventdrop', el[0], event, datedelta, undofunc, ev, {}); // {} = jqui dummy
	},


	/* external element drag-n-drop
	------------------------------------------------------------------------------------------------------------------*/


	// must be called when an external element, via jquery ui, has been dropped onto the calendar.
	// `meta` is the parsed data that has been embedded into the dragging event.
	// `droplocation` is an object that contains the new zoned start/end/allday values for the event.
	reportexternaldrop: function(meta, droplocation, el, ev, ui) {
		var eventprops = meta.eventprops;
		var eventinput;
		var event;

		// try to build an event object and render it. todo: decouple the two
		if (eventprops) {
			eventinput = $.extend({}, eventprops, droplocation);
			event = this.calendar.renderevent(eventinput, meta.stick)[0]; // renderevent returns an array
		}

		this.triggerexternaldrop(event, droplocation, el, ev, ui);
	},


	// triggers external-drop handlers that have subscribed via the api
	triggerexternaldrop: function(event, droplocation, el, ev, ui) {

		// trigger 'drop' regardless of whether element represents an event
		this.trigger('drop', el[0], droplocation.start, ev, ui);

		if (event) {
			this.trigger('eventreceive', null, event); // signal an external event landed
		}
	},


	/* drag-n-drop rendering (for both events and external elements)
	------------------------------------------------------------------------------------------------------------------*/


	// renders a visual indication of a event or external-element drag over the given drop zone.
	// if an external-element, seg will be `null`
	renderdrag: function(droplocation, seg) {
		// subclasses must implement
	},


	// unrenders a visual indication of an event or external-element being dragged.
	unrenderdrag: function() {
		// subclasses must implement
	},


	/* event resizing
	------------------------------------------------------------------------------------------------------------------*/


	// computes if the given event is allowed to be resized from its starting edge
	iseventresizablefromstart: function(event) {
		return this.opt('eventresizablefromstart') && this.iseventresizable(event);
	},


	// computes if the given event is allowed to be resized from its ending edge
	iseventresizablefromend: function(event) {
		return this.iseventresizable(event);
	},


	// computes if the given event is allowed to be resized by the user at all
	iseventresizable: function(event) {
		var source = event.source || {};

		return firstdefined(
			event.durationeditable,
			source.durationeditable,
			this.opt('eventdurationeditable'),
			event.editable,
			source.editable,
			this.opt('editable')
		);
	},


	// must be called when an event in the view has been resized to a new length
	reporteventresize: function(event, resizelocation, largeunit, el, ev) {
		var calendar = this.calendar;
		var mutateresult = calendar.mutateevent(event, resizelocation, largeunit);
		var undofunc = function() {
			mutateresult.undo();
			calendar.reporteventchange();
		};

		this.triggereventresize(event, mutateresult.durationdelta, undofunc, el, ev);
		calendar.reporteventchange(); // will rerender events
	},


	// triggers event-resize handlers that have subscribed via the api
	triggereventresize: function(event, durationdelta, undofunc, el, ev) {
		this.trigger('eventresize', el[0], event, durationdelta, undofunc, ev, {}); // {} = jqui dummy
	},


	/* selection
	------------------------------------------------------------------------------------------------------------------*/


	// selects a date span on the view. `start` and `end` are both moments.
	// `ev` is the native mouse event that begin the interaction.
	select: function(span, ev) {
		this.unselect(ev);
		this.renderselection(span);
		this.reportselection(span, ev);
	},


	// renders a visual indication of the selection
	renderselection: function(span) {
		// subclasses should implement
	},


	// called when a new selection is made. updates internal state and triggers handlers.
	reportselection: function(span, ev) {
		this.isselected = true;
		this.triggerselect(span, ev);
	},


	// triggers handlers to 'select'
	triggerselect: function(span, ev) {
		this.trigger(
			'select',
			null,
			this.calendar.applytimezone(span.start), // convert to calendar's tz for external api
			this.calendar.applytimezone(span.end), // "
			ev
		);
	},


	// undoes a selection. updates in the internal state and triggers handlers.
	// `ev` is the native mouse event that began the interaction.
	unselect: function(ev) {
		if (this.isselected) {
			this.isselected = false;
			if (this.destroyselection) {
				this.destroyselection(); // todo: deprecate
			}
			this.unrenderselection();
			this.trigger('unselect', null, ev);
		}
	},


	// unrenders a visual indication of selection
	unrenderselection: function() {
		// subclasses should implement
	},


	// handler for unselecting when the user clicks something and the 'unselectauto' setting is on
	documentmousedown: function(ev) {
		var ignore;

		// is there a selection, and has the user made a proper left click?
		if (this.isselected && this.opt('unselectauto') && isprimarymousebutton(ev)) {

			// only unselect if the clicked element is not identical to or inside of an 'unselectcancel' element
			ignore = this.opt('unselectcancel');
			if (!ignore || !$(ev.target).closest(ignore).length) {
				this.unselect(ev);
			}
		}
	},


	/* day click
	------------------------------------------------------------------------------------------------------------------*/


	// triggers handlers to 'dayclick'
	// span has start/end of the clicked area. only the start is useful.
	triggerdayclick: function(span, dayel, ev) {
		this.trigger(
			'dayclick',
			dayel,
			this.calendar.applytimezone(span.start), // convert to calendar's timezone for external api
			ev
		);
	},


	/* date utils
	------------------------------------------------------------------------------------------------------------------*/


	// initializes internal variables related to calculating hidden days-of-week
	inithiddendays: function() {
		var hiddendays = this.opt('hiddendays') || []; // array of day-of-week indices that are hidden
		var ishiddendayhash = []; // is the day-of-week hidden? (hash with day-of-week-index -> bool)
		var daycnt = 0;
		var i;

		if (this.opt('weekends') === false) {
			hiddendays.push(0, 6); // 0=sunday, 6=saturday
		}

		for (i = 0; i < 7; i++) {
			if (
				!(ishiddendayhash[i] = $.inarray(i, hiddendays) !== -1)
			) {
				daycnt++;
			}
		}

		if (!daycnt) {
			throw 'invalid hiddendays'; // all days were hidden? bad.
		}

		this.ishiddendayhash = ishiddendayhash;
	},


	// is the current day hidden?
	// `day` is a day-of-week index (0-6), or a moment
	ishiddenday: function(day) {
		if (moment.ismoment(day)) {
			day = day.day();
		}
		return this.ishiddendayhash[day];
	},


	// incrementing the current day until it is no longer a hidden day, returning a copy.
	// if the initial value of `date` is not a hidden day, don't do anything.
	// pass `isexclusive` as `true` if you are dealing with an end date.
	// `inc` defaults to `1` (increment one day forward each time)
	skiphiddendays: function(date, inc, isexclusive) {
		var out = date.clone();
		inc = inc || 1;
		while (
			this.ishiddendayhash[(out.day() + (isexclusive ? inc : 0) + 7) % 7]
		) {
			out.add(inc, 'days');
		}
		return out;
	},


	// returns the date range of the full days the given range visually appears to occupy.
	// returns a new range object.
	computedayrange: function(range) {
		var startday = range.start.clone().striptime(); // the beginning of the day the range starts
		var end = range.end;
		var endday = null;
		var endtimems;

		if (end) {
			endday = end.clone().striptime(); // the beginning of the day the range exclusively ends
			endtimems = +end.time(); // # of milliseconds into `endday`

			// if the end time is actually inclusively part of the next day and is equal to or
			// beyond the next day threshold, adjust the end to be the exclusive end of `endday`.
			// otherwise, leaving it as inclusive will cause it to exclude `endday`.
			if (endtimems && endtimems >= this.nextdaythreshold) {
				endday.add(1, 'days');
			}
		}

		// if no end was specified, or if it is within `startday` but not past nextdaythreshold,
		// assign the default duration of one day.
		if (!end || endday <= startday) {
			endday = startday.clone().add(1, 'days');
		}

		return { start: startday, end: endday };
	},


	// does the given event visually appear to occupy more than one day?
	ismultidayevent: function(event) {
		var range = this.computedayrange(event); // event is range-ish

		return range.end.diff(range.start, 'days') > 1;
	}

});

;;

var calendar = fc.calendar = class.extend({

	dirdefaults: null, // option defaults related to ltr or rtl
	langdefaults: null, // option defaults related to current locale
	overrides: null, // option overrides given to the fullcalendar constructor
	options: null, // all defaults combined with overrides
	viewspeccache: null, // cache of view definitions
	view: null, // current view object
	header: null,
	loadinglevel: 0, // number of simultaneous loading tasks


	// a lot of this class' oop logic is scoped within this constructor function,
	// but in the future, write individual methods on the prototype.
	constructor: calendar_constructor,


	// subclasses can override this for initialization logic after the constructor has been called
	initialize: function() {
	},


	// initializes `this.options` and other important options-related objects
	initoptions: function(overrides) {
		var lang, langdefaults;
		var isrtl, dirdefaults;

		// converts legacy options into non-legacy ones.
		// in the future, when this is removed, don't use `overrides` reference. make a copy.
		overrides = massageoverrides(overrides);

		lang = overrides.lang;
		langdefaults = langoptionhash[lang];
		if (!langdefaults) {
			lang = calendar.defaults.lang;
			langdefaults = langoptionhash[lang] || {};
		}

		isrtl = firstdefined(
			overrides.isrtl,
			langdefaults.isrtl,
			calendar.defaults.isrtl
		);
		dirdefaults = isrtl ? calendar.rtldefaults : {};

		this.dirdefaults = dirdefaults;
		this.langdefaults = langdefaults;
		this.overrides = overrides;
		this.options = mergeoptions([ // merge defaults and overrides. lowest to highest precedence
			calendar.defaults, // global defaults
			dirdefaults,
			langdefaults,
			overrides
		]);
		populateinstancecomputableoptions(this.options);

		this.viewspeccache = {}; // somewhat unrelated
	},


	// gets information about how to create a view. will use a cache.
	getviewspec: function(viewtype) {
		var cache = this.viewspeccache;

		return cache[viewtype] || (cache[viewtype] = this.buildviewspec(viewtype));
	},


	// given a duration singular unit, like "week" or "day", finds a matching view spec.
	// preference is given to views that have corresponding buttons.
	getunitviewspec: function(unit) {
		var viewtypes;
		var i;
		var spec;

		if ($.inarray(unit, intervalunits) != -1) {

			// put views that have buttons first. there will be duplicates, but oh well
			viewtypes = this.header.getviewswithbuttons();
			$.each(fc.views, function(viewtype) { // all views
				viewtypes.push(viewtype);
			});

			for (i = 0; i < viewtypes.length; i++) {
				spec = this.getviewspec(viewtypes[i]);
				if (spec) {
					if (spec.singleunit == unit) {
						return spec;
					}
				}
			}
		}
	},


	// builds an object with information on how to create a given view
	buildviewspec: function(requestedviewtype) {
		var viewoverrides = this.overrides.views || {};
		var specchain = []; // for the view. lowest to highest priority
		var defaultschain = []; // for the view. lowest to highest priority
		var overrideschain = []; // for the view. lowest to highest priority
		var viewtype = requestedviewtype;
		var spec; // for the view
		var overrides; // for the view
		var duration;
		var unit;

		// iterate from the specific view definition to a more general one until we hit an actual view class
		while (viewtype) {
			spec = fcviews[viewtype];
			overrides = viewoverrides[viewtype];
			viewtype = null; // clear. might repopulate for another iteration

			if (typeof spec === 'function') { // todo: deprecate
				spec = { 'class': spec };
			}

			if (spec) {
				specchain.unshift(spec);
				defaultschain.unshift(spec.defaults || {});
				duration = duration || spec.duration;
				viewtype = viewtype || spec.type;
			}

			if (overrides) {
				overrideschain.unshift(overrides); // view-specific option hashes have options at zero-level
				duration = duration || overrides.duration;
				viewtype = viewtype || overrides.type;
			}
		}

		spec = mergeprops(specchain);
		spec.type = requestedviewtype;
		if (!spec['class']) {
			return false;
		}

		if (duration) {
			duration = moment.duration(duration);
			if (duration.valueof()) { // valid?
				spec.duration = duration;
				unit = computeintervalunit(duration);

				// view is a single-unit duration, like "week" or "day"
				// incorporate options for this. lowest priority
				if (duration.as(unit) === 1) {
					spec.singleunit = unit;
					overrideschain.unshift(viewoverrides[unit] || {});
				}
			}
		}

		spec.defaults = mergeoptions(defaultschain);
		spec.overrides = mergeoptions(overrideschain);

		this.buildviewspecoptions(spec);
		this.buildviewspecbuttontext(spec, requestedviewtype);

		return spec;
	},


	// builds and assigns a view spec's options object from its already-assigned defaults and overrides
	buildviewspecoptions: function(spec) {
		spec.options = mergeoptions([ // lowest to highest priority
			calendar.defaults, // global defaults
			spec.defaults, // view's defaults (from viewsubclass.defaults)
			this.dirdefaults,
			this.langdefaults, // locale and dir take precedence over view's defaults!
			this.overrides, // calendar's overrides (options given to constructor)
			spec.overrides // view's overrides (view-specific options)
		]);
		populateinstancecomputableoptions(spec.options);
	},


	// computes and assigns a view spec's buttontext-related options
	buildviewspecbuttontext: function(spec, requestedviewtype) {

		// given an options object with a possible `buttontext` hash, lookup the buttontext for the
		// requested view, falling back to a generic unit entry like "week" or "day"
		function querybuttontext(options) {
			var buttontext = options.buttontext || {};
			return buttontext[requestedviewtype] ||
				(spec.singleunit ? buttontext[spec.singleunit] : null);
		}

		// highest to lowest priority
		spec.buttontextoverride =
			querybuttontext(this.overrides) || // constructor-specified buttontext lookup hash takes precedence
			spec.overrides.buttontext; // `buttontext` for view-specific options is a string

		// highest to lowest priority. mirrors buildviewspecoptions
		spec.buttontextdefault =
			querybuttontext(this.langdefaults) ||
			querybuttontext(this.dirdefaults) ||
			spec.defaults.buttontext || // a single string. from viewsubclass.defaults
			querybuttontext(calendar.defaults) ||
			(spec.duration ? this.humanizeduration(spec.duration) : null) || // like "3 days"
			requestedviewtype; // fall back to given view name
	},


	// given a view name for a custom view or a standard view, creates a ready-to-go view object
	instantiateview: function(viewtype) {
		var spec = this.getviewspec(viewtype);

		return new spec['class'](this, viewtype, spec.options, spec.duration);
	},


	// returns a boolean about whether the view is okay to instantiate at some point
	isvalidviewtype: function(viewtype) {
		return boolean(this.getviewspec(viewtype));
	},


	// should be called when any type of async data fetching begins
	pushloading: function() {
		if (!(this.loadinglevel++)) {
			this.trigger('loading', null, true, this.view);
		}
	},


	// should be called when any type of async data fetching completes
	poploading: function() {
		if (!(--this.loadinglevel)) {
			this.trigger('loading', null, false, this.view);
		}
	},


	// given arguments to the select method in the api, returns a span (unzoned start/end and other info)
	buildselectspan: function(zonedstartinput, zonedendinput) {
		var start = this.moment(zonedstartinput).stripzone();
		var end;

		if (zonedendinput) {
			end = this.moment(zonedendinput).stripzone();
		}
		else if (start.hastime()) {
			end = start.clone().add(this.defaulttimedeventduration);
		}
		else {
			end = start.clone().add(this.defaultalldayeventduration);
		}

		return { start: start, end: end };
	}

});


calendar.mixin(emitter);


function calendar_constructor(element, overrides) {
	var t = this;


	t.initoptions(overrides || {});
	var options = this.options;

	
	// exports
	// -----------------------------------------------------------------------------------

	t.render = render;
	t.destroy = destroy;
	t.refetchevents = refetchevents;
	t.reportevents = reportevents;
	t.reporteventchange = reporteventchange;
	t.rerenderevents = renderevents; // `renderevents` serves as a rerender. an api method
	t.changeview = renderview; // `renderview` will switch to another view
	t.select = select;
	t.unselect = unselect;
	t.prev = prev;
	t.next = next;
	t.prevyear = prevyear;
	t.nextyear = nextyear;
	t.today = today;
	t.gotodate = gotodate;
	t.incrementdate = incrementdate;
	t.zoomto = zoomto;
	t.getdate = getdate;
	t.getcalendar = getcalendar;
	t.getview = getview;
	t.option = option;
	t.trigger = trigger;



	// language-data internals
	// -----------------------------------------------------------------------------------
	// apply overrides to the current language's data


	var localedata = createobject( // make a cheap copy
		getmomentlocaledata(options.lang) // will fall back to en
	);

	if (options.monthnames) {
		localedata._months = options.monthnames;
	}
	if (options.monthnamesshort) {
		localedata._monthsshort = options.monthnamesshort;
	}
	if (options.daynames) {
		localedata._weekdays = options.daynames;
	}
	if (options.daynamesshort) {
		localedata._weekdaysshort = options.daynamesshort;
	}
	if (options.firstday != null) {
		var _week = createobject(localedata._week); // _week: { dow: # }
		_week.dow = options.firstday;
		localedata._week = _week;
	}

	// assign a normalized value, to be used by our .week() moment extension
	localedata._fullcalendar_weekcalc = (function(weekcalc) {
		if (typeof weekcalc === 'function') {
			return weekcalc;
		}
		else if (weekcalc === 'local') {
			return weekcalc;
		}
		else if (weekcalc === 'iso' || weekcalc === 'iso') {
			return 'iso';
		}
	})(options.weeknumbercalculation);



	// calendar-specific date utilities
	// -----------------------------------------------------------------------------------


	t.defaultalldayeventduration = moment.duration(options.defaultalldayeventduration);
	t.defaulttimedeventduration = moment.duration(options.defaulttimedeventduration);


	// builds a moment using the settings of the current calendar: timezone and language.
	// accepts anything the vanilla moment() constructor accepts.
	t.moment = function() {
		var mom;

		if (options.timezone === 'local') {
			mom = fc.moment.apply(null, arguments);

			// force the moment to be local, because fc.moment doesn't guarantee it.
			if (mom.hastime()) { // don't give ambiguously-timed moments a local zone
				mom.local();
			}
		}
		else if (options.timezone === 'utc') {
			mom = fc.moment.utc.apply(null, arguments); // process as utc
		}
		else {
			mom = fc.moment.parsezone.apply(null, arguments); // let the input decide the zone
		}

		if ('_locale' in mom) { // moment 2.8 and above
			mom._locale = localedata;
		}
		else { // pre-moment-2.8
			mom._lang = localedata;
		}

		return mom;
	};


	// returns a boolean about whether or not the calendar knows how to calculate
	// the timezone offset of arbitrary dates in the current timezone.
	t.getisambigtimezone = function() {
		return options.timezone !== 'local' && options.timezone !== 'utc';
	};


	// returns a copy of the given date in the current timezone. has no effect on dates without times.
	t.applytimezone = function(date) {
		if (!date.hastime()) {
			return date.clone();
		}

		var zoneddate = t.moment(date.toarray());
		var timeadjust = date.time() - zoneddate.time();
		var adjustedzoneddate;

		// safari sometimes has problems with this coersion when near dst. adjust if necessary. (bug #2396)
		if (timeadjust) { // is the time result different than expected?
			adjustedzoneddate = zoneddate.clone().add(timeadjust); // add milliseconds
			if (date.time() - adjustedzoneddate.time() === 0) { // does it match perfectly now?
				zoneddate = adjustedzoneddate;
			}
		}

		return zoneddate;
	};


	// returns a moment for the current date, as defined by the client's computer or from the `now` option.
	// will return an moment with an ambiguous timezone.
	t.getnow = function() {
		var now = options.now;
		if (typeof now === 'function') {
			now = now();
		}
		return t.moment(now).stripzone();
	};


	// get an event's normalized end date. if not present, calculate it from the defaults.
	t.geteventend = function(event) {
		if (event.end) {
			return event.end.clone();
		}
		else {
			return t.getdefaulteventend(event.allday, event.start);
		}
	};


	// given an event's allday status and start date, return what its fallback end date should be.
	// todo: rename to computedefaulteventend
	t.getdefaulteventend = function(allday, zonedstart) {
		var end = zonedstart.clone();

		if (allday) {
			end.striptime().add(t.defaultalldayeventduration);
		}
		else {
			end.add(t.defaulttimedeventduration);
		}

		if (t.getisambigtimezone()) {
			end.stripzone(); // we don't know what the tzo should be
		}

		return end;
	};


	// produces a human-readable string for the given duration.
	// side-effect: changes the locale of the given duration.
	t.humanizeduration = function(duration) {
		return (duration.locale || duration.lang).call(duration, options.lang) // works moment-pre-2.8
			.humanize();
	};


	
	// imports
	// -----------------------------------------------------------------------------------


	eventmanager.call(t, options);
	var isfetchneeded = t.isfetchneeded;
	var fetchevents = t.fetchevents;



	// locals
	// -----------------------------------------------------------------------------------


	var _element = element[0];
	var header;
	var headerelement;
	var content;
	var tm; // for making theme classes
	var currentview; // note: keep this in sync with this.view
	var viewsbytype = {}; // holds all instantiated view instances, current or not
	var suggestedviewheight;
	var windowresizeproxy; // wraps the windowresize function
	var ignorewindowresize = 0;
	var events = [];
	var date; // unzoned
	
	
	
	// main rendering
	// -----------------------------------------------------------------------------------


	// compute the initial ambig-timezone date
	if (options.defaultdate != null) {
		date = t.moment(options.defaultdate).stripzone();
	}
	else {
		date = t.getnow(); // getnow already returns unzoned
	}
	
	
	function render() {
		if (!content) {
			initialrender();
		}
		else if (elementvisible()) {
			// mainly for the public api
			calcsize();
			renderview();
		}
	}
	
	
	function initialrender() {
		tm = options.theme ? 'ui' : 'fc';
		element.addclass('fc');

		if (options.isrtl) {
			element.addclass('fc-rtl');
		}
		else {
			element.addclass('fc-ltr');
		}

		if (options.theme) {
			element.addclass('ui-widget');
		}
		else {
			element.addclass('fc-unthemed');
		}

		content = $("<div class='fc-view-container'/>").prependto(element);

		header = t.header = new header(t, options);
		headerelement = header.render();
		if (headerelement) {
			element.prepend(headerelement);
		}

		renderview(options.defaultview);

		if (options.handlewindowresize) {
			windowresizeproxy = debounce(windowresize, options.windowresizedelay); // prevents rapid calls
			$(window).resize(windowresizeproxy);
		}
	}
	
	
	function destroy() {

		if (currentview) {
			currentview.removeelement();

			// note: don't null-out currentview/t.view in case api methods are called after destroy.
			// it is still the "current" view, just not rendered.
		}

		header.removeelement();
		content.remove();
		element.removeclass('fc fc-ltr fc-rtl fc-unthemed ui-widget');

		if (windowresizeproxy) {
			$(window).unbind('resize', windowresizeproxy);
		}
	}
	
	
	function elementvisible() {
		return element.is(':visible');
	}
	
	

	// view rendering
	// -----------------------------------------------------------------------------------


	// renders a view because of a date change, view-type change, or for the first time.
	// if not given a viewtype, keep the current view but render different dates.
	function renderview(viewtype) {
		ignorewindowresize++;

		// if viewtype is changing, remove the old view's rendering
		if (currentview && viewtype && currentview.type !== viewtype) {
			header.deactivatebutton(currentview.type);
			freezecontentheight(); // prevent a scroll jump when view element is removed
			currentview.removeelement();
			currentview = t.view = null;
		}

		// if viewtype changed, or the view was never created, create a fresh view
		if (!currentview && viewtype) {
			currentview = t.view =
				viewsbytype[viewtype] ||
				(viewsbytype[viewtype] = t.instantiateview(viewtype));

			currentview.setelement(
				$("<div class='fc-view fc-" + viewtype + "-view' />").appendto(content)
			);
			header.activatebutton(viewtype);
		}

		if (currentview) {

			// in case the view should render a period of time that is completely hidden
			date = currentview.massagecurrentdate(date);

			// render or rerender the view
			if (
				!currentview.displaying ||
				!date.iswithin(currentview.intervalstart, currentview.intervalend) // implicit date window change
			) {
				if (elementvisible()) {

					currentview.display(date); // will call freezecontentheight
					unfreezecontentheight(); // immediately unfreeze regardless of whether display is async

					// need to do this after view::render, so dates are calculated
					updateheadertitle();
					updatetodaybutton();

					getandrenderevents();
				}
			}
		}

		unfreezecontentheight(); // undo any lone freezecontentheight calls
		ignorewindowresize--;
	}

	

	// resizing
	// -----------------------------------------------------------------------------------


	t.getsuggestedviewheight = function() {
		if (suggestedviewheight === undefined) {
			calcsize();
		}
		return suggestedviewheight;
	};


	t.isheightauto = function() {
		return options.contentheight === 'auto' || options.height === 'auto';
	};
	
	
	function updatesize(shouldrecalc) {
		if (elementvisible()) {

			if (shouldrecalc) {
				_calcsize();
			}

			ignorewindowresize++;
			currentview.updatesize(true); // isresize=true. will poll getsuggestedviewheight() and isheightauto()
			ignorewindowresize--;

			return true; // signal success
		}
	}


	function calcsize() {
		if (elementvisible()) {
			_calcsize();
		}
	}
	
	
	function _calcsize() { // assumes elementvisible
		if (typeof options.contentheight === 'number') { // exists and not 'auto'
			suggestedviewheight = options.contentheight;
		}
		else if (typeof options.height === 'number') { // exists and not 'auto'
			suggestedviewheight = options.height - (headerelement ? headerelement.outerheight(true) : 0);
		}
		else {
			suggestedviewheight = math.round(content.width() / math.max(options.aspectratio, .5));
		}
	}
	
	
	function windowresize(ev) {
		if (
			!ignorewindowresize &&
			ev.target === window && // so we don't process jqui "resize" events that have bubbled up
			currentview.start // view has already been rendered
		) {
			if (updatesize(true)) {
				currentview.trigger('windowresize', _element);
			}
		}
	}
	
	
	
	/* event fetching/rendering
	-----------------------------------------------------------------------------*/
	// todo: going forward, most of this stuff should be directly handled by the view


	function refetchevents() { // can be called as an api method
		destroyevents(); // so that events are cleared before user starts waiting for ajax
		fetchandrenderevents();
	}


	function renderevents() { // destroys old events if previously rendered
		if (elementvisible()) {
			freezecontentheight();
			currentview.displayevents(events);
			unfreezecontentheight();
		}
	}


	function destroyevents() {
		freezecontentheight();
		currentview.clearevents();
		unfreezecontentheight();
	}
	

	function getandrenderevents() {
		if (!options.lazyfetching || isfetchneeded(currentview.start, currentview.end)) {
			fetchandrenderevents();
		}
		else {
			renderevents();
		}
	}


	function fetchandrenderevents() {
		fetchevents(currentview.start, currentview.end);
			// ... will call reportevents
			// ... which will call renderevents
	}

	
	// called when event data arrives
	function reportevents(_events) {
		events = _events;
		renderevents();
	}


	// called when a single event's data has been changed
	function reporteventchange() {
		renderevents();
	}



	/* header updating
	-----------------------------------------------------------------------------*/


	function updateheadertitle() {
		header.updatetitle(currentview.title);
	}


	function updatetodaybutton() {
		var now = t.getnow();
		if (now.iswithin(currentview.intervalstart, currentview.intervalend)) {
			header.disablebutton('today');
		}
		else {
			header.enablebutton('today');
		}
	}
	


	/* selection
	-----------------------------------------------------------------------------*/
	

	// this public method receives start/end dates in any format, with any timezone
	function select(zonedstartinput, zonedendinput) {
		currentview.select(
			t.buildselectspan.apply(t, arguments)
		);
	}
	

	function unselect() { // safe to be called before renderview
		if (currentview) {
			currentview.unselect();
		}
	}
	
	
	
	/* date
	-----------------------------------------------------------------------------*/
	
	
	function prev() {
		date = currentview.computeprevdate(date);
		renderview();
	}
	
	
	function next() {
		date = currentview.computenextdate(date);
		renderview();
	}
	
	
	function prevyear() {
		date.add(-1, 'years');
		renderview();
	}
	
	
	function nextyear() {
		date.add(1, 'years');
		renderview();
	}
	
	
	function today() {
		date = t.getnow();
		renderview();
	}
	
	
	function gotodate(zoneddateinput) {
		date = t.moment(zoneddateinput).stripzone();
		renderview();
	}
	
	
	function incrementdate(delta) {
		date.add(moment.duration(delta));
		renderview();
	}


	// forces navigation to a view for the given date.
	// `viewtype` can be a specific view name or a generic one like "week" or "day".
	function zoomto(newdate, viewtype) {
		var spec;

		viewtype = viewtype || 'day'; // day is default zoom
		spec = t.getviewspec(viewtype) || t.getunitviewspec(viewtype);

		date = newdate.clone();
		renderview(spec ? spec.type : null);
	}
	
	
	// for external api
	function getdate() {
		return t.applytimezone(date); // infuse the calendar's timezone
	}



	/* height "freezing"
	-----------------------------------------------------------------------------*/
	// todo: move this into the view

	t.freezecontentheight = freezecontentheight;
	t.unfreezecontentheight = unfreezecontentheight;


	function freezecontentheight() {
		content.css({
			width: '100%',
			height: content.height(),
			overflow: 'hidden'
		});
	}


	function unfreezecontentheight() {
		content.css({
			width: '',
			height: '',
			overflow: ''
		});
	}
	
	
	
	/* misc
	-----------------------------------------------------------------------------*/
	

	function getcalendar() {
		return t;
	}

	
	function getview() {
		return currentview;
	}
	
	
	function option(name, value) {
		if (value === undefined) {
			return options[name];
		}
		if (name == 'height' || name == 'contentheight' || name == 'aspectratio') {
			options[name] = value;
			updatesize(true); // true = allow recalculation of height
		}
	}
	
	
	function trigger(name, thisobj) { // overrides the emitter's trigger method :(
		var args = array.prototype.slice.call(arguments, 2);

		thisobj = thisobj || _element;
		this.triggerwith(name, thisobj, args); // emitter's method

		if (options[name]) {
			return options[name].apply(thisobj, args);
		}
	}

	t.initialize();
}

;;

calendar.defaults = {

	titlerangeseparator: ' \u2014 ', // emphasized dash
	monthyearformat: 'mmmm yyyy', // required for en. other languages rely on datepicker computable option

	defaulttimedeventduration: '02:00:00',
	defaultalldayeventduration: { days: 1 },
	forceeventduration: false,
	nextdaythreshold: '09:00:00', // 9am

	// display
	defaultview: 'month',
	aspectratio: 1.35,
	header: {
		left: 'title',
		center: '',
		right: 'today prev,next'
	},
	weekends: true,
	weeknumbers: false,

	weeknumbertitle: 'w',
	weeknumbercalculation: 'local',
	
	//editable: false,

	//nowindicator: false,

	scrolltime: '06:00:00',
	
	// event ajax
	lazyfetching: true,
	startparam: 'start',
	endparam: 'end',
	timezoneparam: 'timezone',

	timezone: false,

	//alldaydefault: undefined,

	// locale
	isrtl: false,
	buttontext: {
		prev: "prev",
		next: "next",
		prevyear: "prev year",
		nextyear: "next year",
		year: 'year', // todo: locale files need to specify this
		today: 'today',
		month: 'month',
		week: 'week',
		day: 'day'
	},

	buttonicons: {
		prev: 'left-single-arrow',
		next: 'right-single-arrow',
		prevyear: 'left-double-arrow',
		nextyear: 'right-double-arrow'
	},
	
	// jquery-ui theming
	theme: false,
	themebuttonicons: {
		prev: 'circle-triangle-w',
		next: 'circle-triangle-e',
		prevyear: 'seek-prev',
		nextyear: 'seek-next'
	},

	//eventresizablefromstart: false,
	dragopacity: .75,
	dragrevertduration: 500,
	dragscroll: true,
	
	//selectable: false,
	unselectauto: true,
	
	dropaccept: '*',

	eventorder: 'title',

	eventlimit: false,
	eventlimittext: 'more',
	eventlimitclick: 'popover',
	daypopoverformat: 'll',
	
	handlewindowresize: true,
	windowresizedelay: 200 // milliseconds before an updatesize happens
	
};


calendar.englishdefaults = { // used by lang.js
	daypopoverformat: 'dddd, mmmm d'
};


calendar.rtldefaults = { // right-to-left defaults
	header: { // todo: smarter solution (first/center/last ?)
		left: 'next,prev today',
		center: '',
		right: 'title'
	},
	buttonicons: {
		prev: 'right-single-arrow',
		next: 'left-single-arrow',
		prevyear: 'right-double-arrow',
		nextyear: 'left-double-arrow'
	},
	themebuttonicons: {
		prev: 'circle-triangle-e',
		next: 'circle-triangle-w',
		nextyear: 'seek-prev',
		prevyear: 'seek-next'
	}
};

;;

var langoptionhash = fc.langs = {}; // initialize and expose


// todo: document the structure and ordering of a fullcalendar lang file
// todo: rename everything "lang" to "locale", like what the moment project did


// initialize jquery ui datepicker translations while using some of the translations
// will set this as the default language for datepicker.
fc.datepickerlang = function(langcode, dplangcode, dpoptions) {

	// get the fullcalendar internal option hash for this language. create if necessary
	var fcoptions = langoptionhash[langcode] || (langoptionhash[langcode] = {});

	// transfer some simple options from datepicker to fc
	fcoptions.isrtl = dpoptions.isrtl;
	fcoptions.weeknumbertitle = dpoptions.weekheader;

	// compute some more complex options from datepicker
	$.each(dpcomputableoptions, function(name, func) {
		fcoptions[name] = func(dpoptions);
	});

	// is jquery ui datepicker is on the page?
	if ($.datepicker) {

		// register the language data.
		// fullcalendar and momentjs use language codes like "pt-br" but datepicker
		// does it like "pt-br" or if it doesn't have the language, maybe just "pt".
		// make an alias so the language can be referenced either way.
		$.datepicker.regional[dplangcode] =
			$.datepicker.regional[langcode] = // alias
				dpoptions;

		// alias 'en' to the default language data. do this every time.
		$.datepicker.regional.en = $.datepicker.regional[''];

		// set as datepicker's global defaults.
		$.datepicker.setdefaults(dpoptions);
	}
};


// sets fullcalendar-specific translations. will set the language as the global default.
fc.lang = function(langcode, newfcoptions) {
	var fcoptions;
	var momoptions;

	// get the fullcalendar internal option hash for this language. create if necessary
	fcoptions = langoptionhash[langcode] || (langoptionhash[langcode] = {});

	// provided new options for this language? merge them in
	if (newfcoptions) {
		fcoptions = langoptionhash[langcode] = mergeoptions([ fcoptions, newfcoptions ]);
	}

	// compute language options that weren't defined.
	// always do this. newfcoptions can be undefined when initializing from i18n file,
	// so no way to tell if this is an initialization or a default-setting.
	momoptions = getmomentlocaledata(langcode); // will fall back to en
	$.each(momcomputableoptions, function(name, func) {
		if (fcoptions[name] == null) {
			fcoptions[name] = func(momoptions, fcoptions);
		}
	});

	// set it as the default language for fullcalendar
	calendar.defaults.lang = langcode;
};


// note: can't guarantee any of these computations will run because not every language has datepicker
// configs, so make sure there are english fallbacks for these in the defaults file.
var dpcomputableoptions = {

	buttontext: function(dpoptions) {
		return {
			// the translations sometimes wrongly contain html entities
			prev: striphtmlentities(dpoptions.prevtext),
			next: striphtmlentities(dpoptions.nexttext),
			today: striphtmlentities(dpoptions.currenttext)
		};
	},

	// produces format strings like "mmmm yyyy" -> "september 2014"
	monthyearformat: function(dpoptions) {
		return dpoptions.showmonthafteryear ?
			'yyyy[' + dpoptions.yearsuffix + '] mmmm' :
			'mmmm yyyy[' + dpoptions.yearsuffix + ']';
	}

};

var momcomputableoptions = {

	// produces format strings like "ddd m/d" -> "fri 9/15"
	dayofmonthformat: function(momoptions, fcoptions) {
		var format = momoptions.longdateformat('l'); // for the format like "m/d/yyyy"

		// strip the year off the edge, as well as other misc non-whitespace chars
		format = format.replace(/^y+[^\w\s]*|[^\w\s]*y+$/g, '');

		if (fcoptions.isrtl) {
			format += ' ddd'; // for rtl, add day-of-week to end
		}
		else {
			format = 'ddd ' + format; // for ltr, add day-of-week to beginning
		}
		return format;
	},

	// produces format strings like "h:mma" -> "6:00pm"
	mediumtimeformat: function(momoptions) { // can't be called `timeformat` because collides with option
		return momoptions.longdateformat('lt')
			.replace(/\s*a$/i, 'a'); // convert am/pm/am/pm to lowercase. remove any spaces beforehand
	},

	// produces format strings like "h(:mm)a" -> "6pm" / "6:30pm"
	smalltimeformat: function(momoptions) {
		return momoptions.longdateformat('lt')
			.replace(':mm', '(:mm)')
			.replace(/(\wmm)$/, '($1)') // like above, but for foreign langs
			.replace(/\s*a$/i, 'a'); // convert am/pm/am/pm to lowercase. remove any spaces beforehand
	},

	// produces format strings like "h(:mm)t" -> "6p" / "6:30p"
	extrasmalltimeformat: function(momoptions) {
		return momoptions.longdateformat('lt')
			.replace(':mm', '(:mm)')
			.replace(/(\wmm)$/, '($1)') // like above, but for foreign langs
			.replace(/\s*a$/i, 't'); // convert to am/pm/am/pm to lowercase one-letter. remove any spaces beforehand
	},

	// produces format strings like "ha" / "h" -> "6pm" / "18"
	hourformat: function(momoptions) {
		return momoptions.longdateformat('lt')
			.replace(':mm', '')
			.replace(/(\wmm)$/, '') // like above, but for foreign langs
			.replace(/\s*a$/i, 'a'); // convert am/pm/am/pm to lowercase. remove any spaces beforehand
	},

	// produces format strings like "h:mm" -> "6:30" (with no am/pm)
	nomeridiemtimeformat: function(momoptions) {
		return momoptions.longdateformat('lt')
			.replace(/\s*a$/i, ''); // remove trailing am/pm
	}

};


// options that should be computed off live calendar options (considers override options)
// todo: best place for this? related to lang?
// todo: flipping text based on isrtl is a bad idea because the css `direction` might want to handle it
var instancecomputableoptions = {

	// produces format strings for results like "mo 16"
	smalldaydateformat: function(options) {
		return options.isrtl ?
			'd dd' :
			'dd d';
	},

	// produces format strings for results like "wk 5"
	weekformat: function(options) {
		return options.isrtl ?
			'w[ ' + options.weeknumbertitle + ']' :
			'[' + options.weeknumbertitle + ' ]w';
	},

	// produces format strings for results like "wk5"
	smallweekformat: function(options) {
		return options.isrtl ?
			'w[' + options.weeknumbertitle + ']' :
			'[' + options.weeknumbertitle + ']w';
	}

};

function populateinstancecomputableoptions(options) {
	$.each(instancecomputableoptions, function(name, func) {
		if (options[name] == null) {
			options[name] = func(options);
		}
	});
}


// returns moment's internal locale data. if doesn't exist, returns english.
// works with moment-pre-2.8
function getmomentlocaledata(langcode) {
	var func = moment.localedata || moment.langdata;
	return func.call(moment, langcode) ||
		func.call(moment, 'en'); // the newer localdata could return null, so fall back to en
}


// initialize english by forcing computation of moment-derived options.
// also, sets it as the default.
fc.lang('en', calendar.englishdefaults);

;;

/* top toolbar area with buttons and title
----------------------------------------------------------------------------------------------------------------------*/
// todo: rename all header-related things to "toolbar"

function header(calendar, options) {
	var t = this;
	
	// exports
	t.render = render;
	t.removeelement = removeelement;
	t.updatetitle = updatetitle;
	t.activatebutton = activatebutton;
	t.deactivatebutton = deactivatebutton;
	t.disablebutton = disablebutton;
	t.enablebutton = enablebutton;
	t.getviewswithbuttons = getviewswithbuttons;
	
	// locals
	var el = $();
	var viewswithbuttons = [];
	var tm;


	function render() {
		var sections = options.header;

		tm = options.theme ? 'ui' : 'fc';

		if (sections) {
			el = $("<div class='fc-toolbar'/>")
				.append(rendersection('left'))
				.append(rendersection('right'))
				.append(rendersection('center'))
				.append('<div class="fc-clear"/>');

			return el;
		}
	}
	
	
	function removeelement() {
		el.remove();
		el = $();
	}
	
	
	function rendersection(position) {
		var sectionel = $('<div class="fc-' + position + '"/>');
		var buttonstr = options.header[position];

		if (buttonstr) {
			$.each(buttonstr.split(' '), function(i) {
				var groupchildren = $();
				var isonlybuttons = true;
				var groupel;

				$.each(this.split(','), function(j, buttonname) {
					var custombuttonprops;
					var viewspec;
					var buttonclick;
					var overridetext; // text explicitly set by calendar's constructor options. overcomes icons
					var defaulttext;
					var themeicon;
					var normalicon;
					var innerhtml;
					var classes;
					var button; // the element

					if (buttonname == 'title') {
						groupchildren = groupchildren.add($('<h2>&nbsp;</h2>')); // we always want it to take up height
						isonlybuttons = false;
					}
					else {
						if ((custombuttonprops = (calendar.options.custombuttons || {})[buttonname])) {
							buttonclick = function(ev) {
								if (custombuttonprops.click) {
									custombuttonprops.click.call(button[0], ev);
								}
							};
							overridetext = ''; // icons will override text
							defaulttext = custombuttonprops.text;
						}
						else if ((viewspec = calendar.getviewspec(buttonname))) {
							buttonclick = function() {
								calendar.changeview(buttonname);
							};
							viewswithbuttons.push(buttonname);
							overridetext = viewspec.buttontextoverride;
							defaulttext = viewspec.buttontextdefault;
						}
						else if (calendar[buttonname]) { // a calendar method
							buttonclick = function() {
								calendar[buttonname]();
							};
							overridetext = (calendar.overrides.buttontext || {})[buttonname];
							defaulttext = options.buttontext[buttonname]; // everything else is considered default
						}

						if (buttonclick) {

							themeicon =
								custombuttonprops ?
									custombuttonprops.themeicon :
									options.themebuttonicons[buttonname];

							normalicon =
								custombuttonprops ?
									custombuttonprops.icon :
									options.buttonicons[buttonname];

							if (overridetext) {
								innerhtml = htmlescape(overridetext);
							}
							else if (themeicon && options.theme) {
								innerhtml = "<span class='ui-icon ui-icon-" + themeicon + "'></span>";
							}
							else if (normalicon && !options.theme) {
								innerhtml = "<span class='fc-icon fc-icon-" + normalicon + "'></span>";
							}
							else {
								innerhtml = htmlescape(defaulttext);
							}

							classes = [
								'fc-' + buttonname + '-button',
								tm + '-button',
								tm + '-state-default'
							];

							button = $( // type="button" so that it doesn't submit a form
								'<button type="button" class="' + classes.join(' ') + '">' +
									innerhtml +
								'</button>'
								)
								.click(function(ev) {
									// don't process clicks for disabled buttons
									if (!button.hasclass(tm + '-state-disabled')) {

										buttonclick(ev);

										// after the click action, if the button becomes the "active" tab, or disabled,
										// it should never have a hover class, so remove it now.
										if (
											button.hasclass(tm + '-state-active') ||
											button.hasclass(tm + '-state-disabled')
										) {
											button.removeclass(tm + '-state-hover');
										}
									}
								})
								.mousedown(function() {
									// the *down* effect (mouse pressed in).
									// only on buttons that are not the "active" tab, or disabled
									button
										.not('.' + tm + '-state-active')
										.not('.' + tm + '-state-disabled')
										.addclass(tm + '-state-down');
								})
								.mouseup(function() {
									// undo the *down* effect
									button.removeclass(tm + '-state-down');
								})
								.hover(
									function() {
										// the *hover* effect.
										// only on buttons that are not the "active" tab, or disabled
										button
											.not('.' + tm + '-state-active')
											.not('.' + tm + '-state-disabled')
											.addclass(tm + '-state-hover');
									},
									function() {
										// undo the *hover* effect
										button
											.removeclass(tm + '-state-hover')
											.removeclass(tm + '-state-down'); // if mouseleave happens before mouseup
									}
								);

							groupchildren = groupchildren.add(button);
						}
					}
				});

				if (isonlybuttons) {
					groupchildren
						.first().addclass(tm + '-corner-left').end()
						.last().addclass(tm + '-corner-right').end();
				}

				if (groupchildren.length > 1) {
					groupel = $('<div/>');
					if (isonlybuttons) {
						groupel.addclass('fc-button-group');
					}
					groupel.append(groupchildren);
					sectionel.append(groupel);
				}
				else {
					sectionel.append(groupchildren); // 1 or 0 children
				}
			});
		}

		return sectionel;
	}
	
	
	function updatetitle(text) {
		el.find('h2').text(text);
	}
	
	
	function activatebutton(buttonname) {
		el.find('.fc-' + buttonname + '-button')
			.addclass(tm + '-state-active');
	}
	
	
	function deactivatebutton(buttonname) {
		el.find('.fc-' + buttonname + '-button')
			.removeclass(tm + '-state-active');
	}
	
	
	function disablebutton(buttonname) {
		el.find('.fc-' + buttonname + '-button')
			.attr('disabled', 'disabled')
			.addclass(tm + '-state-disabled');
	}
	
	
	function enablebutton(buttonname) {
		el.find('.fc-' + buttonname + '-button')
			.removeattr('disabled')
			.removeclass(tm + '-state-disabled');
	}


	function getviewswithbuttons() {
		return viewswithbuttons;
	}

}

;;

fc.sourcenormalizers = [];
fc.sourcefetchers = [];

var ajaxdefaults = {
	datatype: 'json',
	cache: false
};

var eventguid = 1;


function eventmanager(options) { // assumed to be a calendar
	var t = this;
	
	
	// exports
	t.isfetchneeded = isfetchneeded;
	t.fetchevents = fetchevents;
	t.addeventsource = addeventsource;
	t.removeeventsource = removeeventsource;
	t.updateevent = updateevent;
	t.renderevent = renderevent;
	t.removeevents = removeevents;
	t.clientevents = clientevents;
	t.mutateevent = mutateevent;
	t.normalizeeventdates = normalizeeventdates;
	t.normalizeeventtimes = normalizeeventtimes;
	
	
	// imports
	var reportevents = t.reportevents;
	
	
	// locals
	var stickysource = { events: [] };
	var sources = [ stickysource ];
	var rangestart, rangeend;
	var currentfetchid = 0;
	var pendingsourcecnt = 0;
	var cache = []; // holds events that have already been expanded


	$.each(
		(options.events ? [ options.events ] : []).concat(options.eventsources || []),
		function(i, sourceinput) {
			var source = buildeventsource(sourceinput);
			if (source) {
				sources.push(source);
			}
		}
	);
	
	
	
	/* fetching
	-----------------------------------------------------------------------------*/


	// start and end are assumed to be unzoned
	function isfetchneeded(start, end) {
		return !rangestart || // nothing has been fetched yet?
			start < rangestart || end > rangeend; // is part of the new range outside of the old range?
	}
	
	
	function fetchevents(start, end) {
		rangestart = start;
		rangeend = end;
		cache = [];
		var fetchid = ++currentfetchid;
		var len = sources.length;
		pendingsourcecnt = len;
		for (var i=0; i<len; i++) {
			fetcheventsource(sources[i], fetchid);
		}
	}
	
	
	function fetcheventsource(source, fetchid) {
		_fetcheventsource(source, function(eventinputs) {
			var isarraysource = $.isarray(source.events);
			var i, eventinput;
			var abstractevent;

			if (fetchid == currentfetchid) {

				if (eventinputs) {
					for (i = 0; i < eventinputs.length; i++) {
						eventinput = eventinputs[i];

						if (isarraysource) { // array sources have already been convert to event objects
							abstractevent = eventinput;
						}
						else {
							abstractevent = buildeventfrominput(eventinput, source);
						}

						if (abstractevent) { // not false (an invalid event)
							cache.push.apply(
								cache,
								expandevent(abstractevent) // add individual expanded events to the cache
							);
						}
					}
				}

				pendingsourcecnt--;
				if (!pendingsourcecnt) {
					reportevents(cache);
				}
			}
		});
	}
	
	
	function _fetcheventsource(source, callback) {
		var i;
		var fetchers = fc.sourcefetchers;
		var res;

		for (i=0; i<fetchers.length; i++) {
			res = fetchers[i].call(
				t, // this, the calendar object
				source,
				rangestart.clone(),
				rangeend.clone(),
				options.timezone,
				callback
			);

			if (res === true) {
				// the fetcher is in charge. made its own async request
				return;
			}
			else if (typeof res == 'object') {
				// the fetcher returned a new source. process it
				_fetcheventsource(res, callback);
				return;
			}
		}

		var events = source.events;
		if (events) {
			if ($.isfunction(events)) {
				t.pushloading();
				events.call(
					t, // this, the calendar object
					rangestart.clone(),
					rangeend.clone(),
					options.timezone,
					function(events) {
						callback(events);
						t.poploading();
					}
				);
			}
			else if ($.isarray(events)) {
				callback(events);
			}
			else {
				callback();
			}
		}else{
			var url = source.url;
			if (url) {
				var success = source.success;
				var error = source.error;
				var complete = source.complete;

				// retrieve any outbound get/post $.ajax data from the options
				var customdata;
				if ($.isfunction(source.data)) {
					// supplied as a function that returns a key/value object
					customdata = source.data();
				}
				else {
					// supplied as a straight key/value object
					customdata = source.data;
				}

				// use a copy of the custom data so we can modify the parameters
				// and not affect the passed-in object.
				var data = $.extend({}, customdata || {});

				var startparam = firstdefined(source.startparam, options.startparam);
				var endparam = firstdefined(source.endparam, options.endparam);
				var timezoneparam = firstdefined(source.timezoneparam, options.timezoneparam);

				if (startparam) {
					data[startparam] = rangestart.format();
				}
				if (endparam) {
					data[endparam] = rangeend.format();
				}
				if (options.timezone && options.timezone != 'local') {
					data[timezoneparam] = options.timezone;
				}

				t.pushloading();
				$.ajax($.extend({}, ajaxdefaults, source, {
					data: data,
					success: function(events) {
						events = events || [];
						var res = applyall(success, this, arguments);
						if ($.isarray(res)) {
							events = res;
						}
						callback(events);
					},
					error: function() {
						applyall(error, this, arguments);
						callback();
					},
					complete: function() {
						applyall(complete, this, arguments);
						t.poploading();
					}
				}));
			}else{
				callback();
			}
		}
	}
	
	
	
	/* sources
	-----------------------------------------------------------------------------*/
	

	function addeventsource(sourceinput) {
		var source = buildeventsource(sourceinput);
		if (source) {
			sources.push(source);
			pendingsourcecnt++;
			fetcheventsource(source, currentfetchid); // will eventually call reportevents
		}
	}


	function buildeventsource(sourceinput) { // will return undefined if invalid source
		var normalizers = fc.sourcenormalizers;
		var source;
		var i;

		if ($.isfunction(sourceinput) || $.isarray(sourceinput)) {
			source = { events: sourceinput };
		}
		else if (typeof sourceinput === 'string') {
			source = { url: sourceinput };
		}
		else if (typeof sourceinput === 'object') {
			source = $.extend({}, sourceinput); // shallow copy
		}

		if (source) {

			// todo: repeat code, same code for event classnames
			if (source.classname) {
				if (typeof source.classname === 'string') {
					source.classname = source.classname.split(/\s+/);
				}
				// otherwise, assumed to be an array
			}
			else {
				source.classname = [];
			}

			// for array sources, we convert to standard event objects up front
			if ($.isarray(source.events)) {
				source.origarray = source.events; // for removeeventsource
				source.events = $.map(source.events, function(eventinput) {
					return buildeventfrominput(eventinput, source);
				});
			}

			for (i=0; i<normalizers.length; i++) {
				normalizers[i].call(t, source);
			}

			return source;
		}
	}


	function removeeventsource(source) {
		sources = $.grep(sources, function(src) {
			return !issourcesequal(src, source);
		});
		// remove all client events from that source
		cache = $.grep(cache, function(e) {
			return !issourcesequal(e.source, source);
		});
		reportevents(cache);
	}


	function issourcesequal(source1, source2) {
		return source1 && source2 && getsourceprimitive(source1) == getsourceprimitive(source2);
	}


	function getsourceprimitive(source) {
		return (
			(typeof source === 'object') ? // a normalized event source?
				(source.origarray || source.googlecalendarid || source.url || source.events) : // get the primitive
				null
		) ||
		source; // the given argument *is* the primitive
	}
	
	
	
	/* manipulation
	-----------------------------------------------------------------------------*/


	// only ever called from the externally-facing api
	function updateevent(event) {

		// massage start/end values, even if date string values
		event.start = t.moment(event.start);
		if (event.end) {
			event.end = t.moment(event.end);
		}
		else {
			event.end = null;
		}

		mutateevent(event, getmisceventprops(event)); // will handle start/end/allday normalization
		reportevents(cache); // reports event modifications (so we can redraw)
	}


	// returns a hash of misc event properties that should be copied over to related events.
	function getmisceventprops(event) {
		var props = {};

		$.each(event, function(name, val) {
			if (ismisceventpropname(name)) {
				if (val !== undefined && isatomic(val)) { // a defined non-object
					props[name] = val;
				}
			}
		});

		return props;
	}

	// non-date-related, non-id-related, non-secret
	function ismisceventpropname(name) {
		return !/^_|^(id|allday|start|end)$/.test(name);
	}

	
	// returns the expanded events that were created
	function renderevent(eventinput, stick) {
		var abstractevent = buildeventfrominput(eventinput);
		var events;
		var i, event;

		if (abstractevent) { // not false (a valid input)
			events = expandevent(abstractevent);

			for (i = 0; i < events.length; i++) {
				event = events[i];

				if (!event.source) {
					if (stick) {
						stickysource.events.push(event);
						event.source = stickysource;
					}
					cache.push(event);
				}
			}

			reportevents(cache);

			return events;
		}

		return [];
	}
	
	
	function removeevents(filter) {
		var eventid;
		var i;

		if (filter == null) { // null or undefined. remove all events
			filter = function() { return true; }; // will always match
		}
		else if (!$.isfunction(filter)) { // an event id
			eventid = filter + '';
			filter = function(event) {
				return event._id == eventid;
			};
		}

		// purge event(s) from our local cache
		cache = $.grep(cache, filter, true); // inverse=true

		// remove events from array sources.
		// this works because they have been converted to official event objects up front.
		// (and as a result, event._id has been calculated).
		for (i=0; i<sources.length; i++) {
			if ($.isarray(sources[i].events)) {
				sources[i].events = $.grep(sources[i].events, filter, true);
			}
		}

		reportevents(cache);
	}
	
	
	function clientevents(filter) {
		if ($.isfunction(filter)) {
			return $.grep(cache, filter);
		}
		else if (filter != null) { // not null, not undefined. an event id
			filter += '';
			return $.grep(cache, function(e) {
				return e._id == filter;
			});
		}
		return cache; // else, return all
	}
	
	
	
	/* event normalization
	-----------------------------------------------------------------------------*/


	// given a raw object with key/value properties, returns an "abstract" event object.
	// an "abstract" event is an event that, if recurring, will not have been expanded yet.
	// will return `false` when input is invalid.
	// `source` is optional
	function buildeventfrominput(input, source) {
		var out = {};
		var start, end;
		var allday;

		if (options.eventdatatransform) {
			input = options.eventdatatransform(input);
		}
		if (source && source.eventdatatransform) {
			input = source.eventdatatransform(input);
		}

		// copy all properties over to the resulting object.
		// the special-case properties will be copied over afterwards.
		$.extend(out, input);

		if (source) {
			out.source = source;
		}

		out._id = input._id || (input.id === undefined ? '_fc' + eventguid++ : input.id + '');

		if (input.classname) {
			if (typeof input.classname == 'string') {
				out.classname = input.classname.split(/\s+/);
			}
			else { // assumed to be an array
				out.classname = input.classname;
			}
		}
		else {
			out.classname = [];
		}

		start = input.start || input.date; // "date" is an alias for "start"
		end = input.end;

		// parse as a time (duration) if applicable
		if (istimestring(start)) {
			start = moment.duration(start);
		}
		if (istimestring(end)) {
			end = moment.duration(end);
		}

		if (input.dow || moment.isduration(start) || moment.isduration(end)) {

			// the event is "abstract" (recurring) so don't calculate exact start/end dates just yet
			out.start = start ? moment.duration(start) : null; // will be a duration or null
			out.end = end ? moment.duration(end) : null; // will be a duration or null
			out._recurring = true; // our internal marker
		}
		else {

			if (start) {
				start = t.moment(start);
				if (!start.isvalid()) {
					return false;
				}
			}

			if (end) {
				end = t.moment(end);
				if (!end.isvalid()) {
					end = null; // let defaults take over
				}
			}

			allday = input.allday;
			if (allday === undefined) { // still undefined? fallback to default
				allday = firstdefined(
					source ? source.alldaydefault : undefined,
					options.alldaydefault
				);
				// still undefined? normalizeeventdates will calculate it
			}

			assigndatestoevent(start, end, allday, out);
		}

		return out;
	}


	// normalizes and assigns the given dates to the given partially-formed event object.
	// note: mutates the given start/end moments. does not make a copy.
	function assigndatestoevent(start, end, allday, event) {
		event.start = start;
		event.end = end;
		event.allday = allday;
		normalizeeventdates(event);
		backupeventdates(event);
	}


	// ensures proper values for allday/start/end. accepts an event object, or a plain object with event-ish properties.
	// note: will modify the given object.
	function normalizeeventdates(eventprops) {

		normalizeeventtimes(eventprops);

		if (eventprops.end && !eventprops.end.isafter(eventprops.start)) {
			eventprops.end = null;
		}

		if (!eventprops.end) {
			if (options.forceeventduration) {
				eventprops.end = t.getdefaulteventend(eventprops.allday, eventprops.start);
			}
			else {
				eventprops.end = null;
			}
		}
	}


	// ensures the allday property exists and the timeliness of the start/end dates are consistent
	function normalizeeventtimes(eventprops) {
		if (eventprops.allday == null) {
			eventprops.allday = !(eventprops.start.hastime() || (eventprops.end && eventprops.end.hastime()));
		}

		if (eventprops.allday) {
			eventprops.start.striptime();
			if (eventprops.end) {
				// todo: consider nextdaythreshold here? if so, will require a lot of testing and adjustment
				eventprops.end.striptime();
			}
		}
		else {
			if (!eventprops.start.hastime()) {
				eventprops.start = t.applytimezone(eventprops.start.time(0)); // will assign a 00:00 time
			}
			if (eventprops.end && !eventprops.end.hastime()) {
				eventprops.end = t.applytimezone(eventprops.end.time(0)); // will assign a 00:00 time
			}
		}
	}


	// if the given event is a recurring event, break it down into an array of individual instances.
	// if not a recurring event, return an array with the single original event.
	// if given a falsy input (probably because of a failed buildeventfrominput call), returns an empty array.
	// hack: can override the recurring window by providing custom rangestart/rangeend (for businesshours).
	function expandevent(abstractevent, _rangestart, _rangeend) {
		var events = [];
		var dowhash;
		var dow;
		var i;
		var date;
		var starttime, endtime;
		var start, end;
		var event;

		_rangestart = _rangestart || rangestart;
		_rangeend = _rangeend || rangeend;

		if (abstractevent) {
			if (abstractevent._recurring) {

				// make a boolean hash as to whether the event occurs on each day-of-week
				if ((dow = abstractevent.dow)) {
					dowhash = {};
					for (i = 0; i < dow.length; i++) {
						dowhash[dow[i]] = true;
					}
				}

				// iterate through every day in the current range
				date = _rangestart.clone().striptime(); // holds the date of the current day
				while (date.isbefore(_rangeend)) {

					if (!dowhash || dowhash[date.day()]) { // if everyday, or this particular day-of-week

						starttime = abstractevent.start; // the stored start and end properties are times (durations)
						endtime = abstractevent.end; // "
						start = date.clone();
						end = null;

						if (starttime) {
							start = start.time(starttime);
						}
						if (endtime) {
							end = date.clone().time(endtime);
						}

						event = $.extend({}, abstractevent); // make a copy of the original
						assigndatestoevent(
							start, end,
							!starttime && !endtime, // allday?
							event
						);
						events.push(event);
					}

					date.add(1, 'days');
				}
			}
			else {
				events.push(abstractevent); // return the original event. will be a one-item array
			}
		}

		return events;
	}



	/* event modification math
	-----------------------------------------------------------------------------------------*/


	// modifies an event and all related events by applying the given properties.
	// special date-diffing logic is used for manipulation of dates.
	// if `props` does not contain start/end dates, the updated values are assumed to be the event's current start/end.
	// all date comparisons are done against the event's pristine _start and _end dates.
	// returns an object with delta information and a function to undo all operations.
	// for making computations in a granularity greater than day/time, specify largeunit.
	// note: the given `newprops` might be mutated for normalization purposes.
	function mutateevent(event, newprops, largeunit) {
		var miscprops = {};
		var oldprops;
		var clearend;
		var startdelta;
		var enddelta;
		var durationdelta;
		var undofunc;

		// diffs the dates in the appropriate way, returning a duration
		function diffdates(date1, date0) { // date1 - date0
			if (largeunit) {
				return diffbyunit(date1, date0, largeunit);
			}
			else if (newprops.allday) {
				return diffday(date1, date0);
			}
			else {
				return diffdaytime(date1, date0);
			}
		}

		newprops = newprops || {};

		// normalize new date-related properties
		if (!newprops.start) {
			newprops.start = event.start.clone();
		}
		if (newprops.end === undefined) {
			newprops.end = event.end ? event.end.clone() : null;
		}
		if (newprops.allday == null) { // is null or undefined?
			newprops.allday = event.allday;
		}
		normalizeeventdates(newprops);

		// create normalized versions of the original props to compare against
		// need a real end value, for diffing
		oldprops = {
			start: event._start.clone(),
			end: event._end ? event._end.clone() : t.getdefaulteventend(event._allday, event._start),
			allday: newprops.allday // normalize the dates in the same regard as the new properties
		};
		normalizeeventdates(oldprops);

		// need to clear the end date if explicitly changed to null
		clearend = event._end !== null && newprops.end === null;

		// compute the delta for moving the start date
		startdelta = diffdates(newprops.start, oldprops.start);

		// compute the delta for moving the end date
		if (newprops.end) {
			enddelta = diffdates(newprops.end, oldprops.end);
			durationdelta = enddelta.subtract(startdelta);
		}
		else {
			durationdelta = null;
		}

		// gather all non-date-related properties
		$.each(newprops, function(name, val) {
			if (ismisceventpropname(name)) {
				if (val !== undefined) {
					miscprops[name] = val;
				}
			}
		});

		// apply the operations to the event and all related events
		undofunc = mutateevents(
			clientevents(event._id), // get events with this id
			clearend,
			newprops.allday,
			startdelta,
			durationdelta,
			miscprops
		);

		return {
			datedelta: startdelta,
			durationdelta: durationdelta,
			undo: undofunc
		};
	}


	// modifies an array of events in the following ways (operations are in order):
	// - clear the event's `end`
	// - convert the event to allday
	// - add `datedelta` to the start and end
	// - add `durationdelta` to the event's duration
	// - assign `miscprops` to the event
	//
	// returns a function that can be called to undo all the operations.
	//
	// todo: don't use so many closures. possible memory issues when lots of events with same id.
	//
	function mutateevents(events, clearend, allday, datedelta, durationdelta, miscprops) {
		var isambigtimezone = t.getisambigtimezone();
		var undofunctions = [];

		// normalize zero-length deltas to be null
		if (datedelta && !datedelta.valueof()) { datedelta = null; }
		if (durationdelta && !durationdelta.valueof()) { durationdelta = null; }

		$.each(events, function(i, event) {
			var oldprops;
			var newprops;

			// build an object holding all the old values, both date-related and misc.
			// for the undo function.
			oldprops = {
				start: event.start.clone(),
				end: event.end ? event.end.clone() : null,
				allday: event.allday
			};
			$.each(miscprops, function(name) {
				oldprops[name] = event[name];
			});

			// new date-related properties. work off the original date snapshot.
			// ok to use references because they will be thrown away when backupeventdates is called.
			newprops = {
				start: event._start,
				end: event._end,
				allday: allday // normalize the dates in the same regard as the new properties
			};
			normalizeeventdates(newprops); // massages start/end/allday

			// strip or ensure the end date
			if (clearend) {
				newprops.end = null;
			}
			else if (durationdelta && !newprops.end) { // the duration translation requires an end date
				newprops.end = t.getdefaulteventend(newprops.allday, newprops.start);
			}

			if (datedelta) {
				newprops.start.add(datedelta);
				if (newprops.end) {
					newprops.end.add(datedelta);
				}
			}

			if (durationdelta) {
				newprops.end.add(durationdelta); // end already ensured above
			}

			// if the dates have changed, and we know it is impossible to recompute the
			// timezone offsets, strip the zone.
			if (
				isambigtimezone &&
				!newprops.allday &&
				(datedelta || durationdelta)
			) {
				newprops.start.stripzone();
				if (newprops.end) {
					newprops.end.stripzone();
				}
			}

			$.extend(event, miscprops, newprops); // copy over misc props, then date-related props
			backupeventdates(event); // regenerate internal _start/_end/_allday

			undofunctions.push(function() {
				$.extend(event, oldprops);
				backupeventdates(event); // regenerate internal _start/_end/_allday
			});
		});

		return function() {
			for (var i = 0; i < undofunctions.length; i++) {
				undofunctions[i]();
			}
		};
	}


	/* business hours
	-----------------------------------------------------------------------------------------*/

	t.getbusinesshoursevents = getbusinesshoursevents;


	// returns an array of events as to when the business hours occur in the given view.
	// abuse of our event system :(
	function getbusinesshoursevents(wholeday) {
		var optionval = options.businesshours;
		var defaultval = {
			classname: 'fc-nonbusiness',
			start: '09:00',
			end: '17:00',
			dow: [ 1, 2, 3, 4, 5 ], // monday - friday
			rendering: 'inverse-background'
		};
		var view = t.getview();
		var eventinput;

		if (optionval) { // `true` (which means "use the defaults") or an override object
			eventinput = $.extend(
				{}, // copy to a new object in either case
				defaultval,
				typeof optionval === 'object' ? optionval : {} // override the defaults
			);
		}

		if (eventinput) {

			// if a whole-day series is requested, clear the start/end times
			if (wholeday) {
				eventinput.start = null;
				eventinput.end = null;
			}

			return expandevent(
				buildeventfrominput(eventinput),
				view.start,
				view.end
			);
		}

		return [];
	}


	/* overlapping / constraining
	-----------------------------------------------------------------------------------------*/

	t.iseventspanallowed = iseventspanallowed;
	t.isexternalspanallowed = isexternalspanallowed;
	t.isselectionspanallowed = isselectionspanallowed;


	// determines if the given event can be relocated to the given span (unzoned start/end with other misc data)
	function iseventspanallowed(span, event) {
		var source = event.source || {};
		var constraint = firstdefined(
			event.constraint,
			source.constraint,
			options.eventconstraint
		);
		var overlap = firstdefined(
			event.overlap,
			source.overlap,
			options.eventoverlap
		);
		return isspanallowed(span, constraint, overlap, event);
	}


	// determines if an external event can be relocated to the given span (unzoned start/end with other misc data)
	function isexternalspanallowed(eventspan, eventlocation, eventprops) {
		var eventinput;
		var event;

		// note: very similar logic is in view's reportexternaldrop
		if (eventprops) {
			eventinput = $.extend({}, eventprops, eventlocation);
			event = expandevent(buildeventfrominput(eventinput))[0];
		}

		if (event) {
			return iseventspanallowed(eventspan, event);
		}
		else { // treat it as a selection

			return isselectionspanallowed(eventspan);
		}
	}


	// determines the given span (unzoned start/end with other misc data) can be selected.
	function isselectionspanallowed(span) {
		return isspanallowed(span, options.selectconstraint, options.selectoverlap);
	}


	// returns true if the given span (caused by an event drop/resize or a selection) is allowed to exist
	// according to the constraint/overlap settings.
	// `event` is not required if checking a selection.
	function isspanallowed(span, constraint, overlap, event) {
		var constraintevents;
		var anycontainment;
		var peerevents;
		var i, peerevent;
		var peeroverlap;

		// the range must be fully contained by at least one of produced constraint events
		if (constraint != null) {

			// not treated as an event! intermediate data structure
			// todo: use ranges in the future
			constraintevents = constrainttoevents(constraint);

			anycontainment = false;
			for (i = 0; i < constraintevents.length; i++) {
				if (eventcontainsrange(constraintevents[i], span)) {
					anycontainment = true;
					break;
				}
			}

			if (!anycontainment) {
				return false;
			}
		}

		peerevents = t.getpeerevents(span, event);

		for (i = 0; i < peerevents.length; i++)  {
			peerevent = peerevents[i];

			// there needs to be an actual intersection before disallowing anything
			if (eventintersectsrange(peerevent, span)) {

				// evaluate overlap for the given range and short-circuit if necessary
				if (overlap === false) {
					return false;
				}
				// if the event's overlap is a test function, pass the peer event in question as the first param
				else if (typeof overlap === 'function' && !overlap(peerevent, event)) {
					return false;
				}

				// if we are computing if the given range is allowable for an event, consider the other event's
				// eventobject-specific or source-specific `overlap` property
				if (event) {
					peeroverlap = firstdefined(
						peerevent.overlap,
						(peerevent.source || {}).overlap
						// we already considered the global `eventoverlap`
					);
					if (peeroverlap === false) {
						return false;
					}
					// if the peer event's overlap is a test function, pass the subject event as the first param
					if (typeof peeroverlap === 'function' && !peeroverlap(event, peerevent)) {
						return false;
					}
				}
			}
		}

		return true;
	}


	// given an event input from the api, produces an array of event objects. possible event inputs:
	// 'businesshours'
	// an event id (number or string)
	// an object with specific start/end dates or a recurring event (like what businesshours accepts)
	function constrainttoevents(constraintinput) {

		if (constraintinput === 'businesshours') {
			return getbusinesshoursevents();
		}

		if (typeof constraintinput === 'object') {
			return expandevent(buildeventfrominput(constraintinput));
		}

		return clientevents(constraintinput); // probably an id
	}


	// does the event's date range fully contain the given range?
	// start/end already assumed to have stripped zones :(
	function eventcontainsrange(event, range) {
		var eventstart = event.start.clone().stripzone();
		var eventend = t.geteventend(event).stripzone();

		return range.start >= eventstart && range.end <= eventend;
	}


	// does the event's date range intersect with the given range?
	// start/end already assumed to have stripped zones :(
	function eventintersectsrange(event, range) {
		var eventstart = event.start.clone().stripzone();
		var eventend = t.geteventend(event).stripzone();

		return range.start < eventend && range.end > eventstart;
	}


	t.geteventcache = function() {
		return cache;
	};

}


// returns a list of events that the given event should be compared against when being considered for a move to
// the specified span. attached to the calendar's prototype because eventmanager is a mixin for a calendar.
calendar.prototype.getpeerevents = function(span, event) {
	var cache = this.geteventcache();
	var peerevents = [];
	var i, otherevent;

	for (i = 0; i < cache.length; i++) {
		otherevent = cache[i];
		if (
			!event ||
			event._id !== otherevent._id // don't compare the event to itself or other related [repeating] events
		) {
			peerevents.push(otherevent);
		}
	}

	return peerevents;
};


// updates the "backup" properties, which are preserved in order to compute diffs later on.
function backupeventdates(event) {
	event._allday = event.allday;
	event._start = event.start.clone();
	event._end = event.end ? event.end.clone() : null;
}

;;

/* an abstract class for the "basic" views, as well as month view. renders one or more rows of day cells.
----------------------------------------------------------------------------------------------------------------------*/
// it is a manager for a daygrid subcomponent, which does most of the heavy lifting.
// it is responsible for managing width/height.

var basicview = fc.basicview = view.extend({

	daygridclass: daygrid, // class the daygrid will be instantiated from (overridable by subclasses)
	daygrid: null, // the main subcomponent that does most of the heavy lifting

	daynumbersvisible: false, // display day numbers on each day cell?
	weeknumbersvisible: false, // display week numbers along the side?

	weeknumberwidth: null, // width of all the week-number cells running down the side

	headcontainerel: null, // div that hold's the daygrid's rendered date header
	headrowel: null, // the fake row element of the day-of-week header


	initialize: function() {
		this.daygrid = this.instantiatedaygrid();
	},


	// generates the daygrid object this view needs. draws from this.daygridclass
	instantiatedaygrid: function() {
		// generate a subclass on the fly with basicview-specific behavior
		// todo: cache this subclass
		var subclass = this.daygridclass.extend(basicdaygridmethods);

		return new subclass(this);
	},


	// sets the display range and computes all necessary dates
	setrange: function(range) {
		view.prototype.setrange.call(this, range); // call the super-method

		this.daygrid.breakonweeks = /year|month|week/.test(this.intervalunit); // do before setrange
		this.daygrid.setrange(range);
	},


	// compute the value to feed into setrange. overrides superclass.
	computerange: function(date) {
		var range = view.prototype.computerange.call(this, date); // get value from the super-method

		// year and month views should be aligned with weeks. this is already done for week
		if (/year|month/.test(range.intervalunit)) {
			range.start.startof('week');
			range.start = this.skiphiddendays(range.start);

			// make end-of-week if not already
			if (range.end.weekday()) {
				range.end.add(1, 'week').startof('week');
				range.end = this.skiphiddendays(range.end, -1, true); // exclusively move backwards
			}
		}

		return range;
	},


	// renders the view into `this.el`, which should already be assigned
	renderdates: function() {

		this.daynumbersvisible = this.daygrid.rowcnt > 1; // todo: make grid responsible
		this.weeknumbersvisible = this.opt('weeknumbers');
		this.daygrid.numbersvisible = this.daynumbersvisible || this.weeknumbersvisible;

		this.el.addclass('fc-basic-view').html(this.renderskeletonhtml());
		this.renderhead();

		this.scrollerel = this.el.find('.fc-day-grid-container');

		this.daygrid.setelement(this.el.find('.fc-day-grid'));
		this.daygrid.renderdates(this.hasrigidrows());
	},


	// render the day-of-week headers
	renderhead: function() {
		this.headcontainerel =
			this.el.find('.fc-head-container')
				.html(this.daygrid.renderheadhtml());
		this.headrowel = this.headcontainerel.find('.fc-row');
	},


	// unrenders the content of the view. since we haven't separated skeleton rendering from date rendering,
	// always completely kill the daygrid's rendering.
	unrenderdates: function() {
		this.daygrid.unrenderdates();
		this.daygrid.removeelement();
	},


	renderbusinesshours: function() {
		this.daygrid.renderbusinesshours();
	},


	// builds the html skeleton for the view.
	// the day-grid component will render inside of a container defined by this html.
	renderskeletonhtml: function() {
		return '' +
			'<table>' +
				'<thead class="fc-head">' +
					'<tr>' +
						'<td class="fc-head-container ' + this.widgetheaderclass + '"></td>' +
					'</tr>' +
				'</thead>' +
				'<tbody class="fc-body">' +
					'<tr>' +
						'<td class="' + this.widgetcontentclass + '">' +
							'<div class="fc-day-grid-container">' +
								'<div class="fc-day-grid"/>' +
							'</div>' +
						'</td>' +
					'</tr>' +
				'</tbody>' +
			'</table>';
	},


	// generates an html attribute string for setting the width of the week number column, if it is known
	weeknumberstyleattr: function() {
		if (this.weeknumberwidth !== null) {
			return 'style="width:' + this.weeknumberwidth + 'px"';
		}
		return '';
	},


	// determines whether each row should have a constant height
	hasrigidrows: function() {
		var eventlimit = this.opt('eventlimit');
		return eventlimit && typeof eventlimit !== 'number';
	},


	/* dimensions
	------------------------------------------------------------------------------------------------------------------*/


	// refreshes the horizontal dimensions of the view
	updatewidth: function() {
		if (this.weeknumbersvisible) {
			// make sure all week number cells running down the side have the same width.
			// record the width for cells created later.
			this.weeknumberwidth = matchcellwidths(
				this.el.find('.fc-week-number')
			);
		}
	},


	// adjusts the vertical dimensions of the view to the specified values
	setheight: function(totalheight, isauto) {
		var eventlimit = this.opt('eventlimit');
		var scrollerheight;

		// reset all heights to be natural
		unsetscroller(this.scrollerel);
		uncompensatescroll(this.headrowel);

		this.daygrid.removesegpopover(); // kill the "more" popover if displayed

		// is the event limit a constant level number?
		if (eventlimit && typeof eventlimit === 'number') {
			this.daygrid.limitrows(eventlimit); // limit the levels first so the height can redistribute after
		}

		scrollerheight = this.computescrollerheight(totalheight);
		this.setgridheight(scrollerheight, isauto);

		// is the event limit dynamically calculated?
		if (eventlimit && typeof eventlimit !== 'number') {
			this.daygrid.limitrows(eventlimit); // limit the levels after the grid's row heights have been set
		}

		if (!isauto && setpotentialscroller(this.scrollerel, scrollerheight)) { // using scrollbars?

			compensatescroll(this.headrowel, getscrollbarwidths(this.scrollerel));

			// doing the scrollbar compensation might have created text overflow which created more height. redo
			scrollerheight = this.computescrollerheight(totalheight);
			this.scrollerel.height(scrollerheight);
		}
	},


	// sets the height of just the daygrid component in this view
	setgridheight: function(height, isauto) {
		if (isauto) {
			undistributeheight(this.daygrid.rowels); // let the rows be their natural height with no expanding
		}
		else {
			distributeheight(this.daygrid.rowels, height, true); // true = compensate for height-hogging rows
		}
	},


	/* hit areas
	------------------------------------------------------------------------------------------------------------------*/
	// forward all hit-related method calls to daygrid


	preparehits: function() {
		this.daygrid.preparehits();
	},


	releasehits: function() {
		this.daygrid.releasehits();
	},


	queryhit: function(left, top) {
		return this.daygrid.queryhit(left, top);
	},


	gethitspan: function(hit) {
		return this.daygrid.gethitspan(hit);
	},


	gethitel: function(hit) {
		return this.daygrid.gethitel(hit);
	},


	/* events
	------------------------------------------------------------------------------------------------------------------*/


	// renders the given events onto the view and populates the segments array
	renderevents: function(events) {
		this.daygrid.renderevents(events);

		this.updateheight(); // must compensate for events that overflow the row
	},


	// retrieves all segment objects that are rendered in the view
	geteventsegs: function() {
		return this.daygrid.geteventsegs();
	},


	// unrenders all event elements and clears internal segment data
	unrenderevents: function() {
		this.daygrid.unrenderevents();

		// we don't need to call updateheight() because:
		// a) a renderevents() call always happens after this, which will eventually call updateheight()
		// b) in ie8, this causes a flash whenever events are rerendered
	},


	/* dragging (for both events and external elements)
	------------------------------------------------------------------------------------------------------------------*/


	// a returned value of `true` signals that a mock "helper" event has been rendered.
	renderdrag: function(droplocation, seg) {
		return this.daygrid.renderdrag(droplocation, seg);
	},


	unrenderdrag: function() {
		this.daygrid.unrenderdrag();
	},


	/* selection
	------------------------------------------------------------------------------------------------------------------*/


	// renders a visual indication of a selection
	renderselection: function(span) {
		this.daygrid.renderselection(span);
	},


	// unrenders a visual indications of a selection
	unrenderselection: function() {
		this.daygrid.unrenderselection();
	}

});


// methods that will customize the rendering behavior of the basicview's daygrid
var basicdaygridmethods = {


	// generates the html that will go before the day-of week header cells
	renderheadintrohtml: function() {
		var view = this.view;

		if (view.weeknumbersvisible) {
			return '' +
				'<th class="fc-week-number ' + view.widgetheaderclass + '" ' + view.weeknumberstyleattr() + '>' +
					'<span>' + // needed for matchcellwidths
						htmlescape(view.opt('weeknumbertitle')) +
					'</span>' +
				'</th>';
		}

		return '';
	},


	// generates the html that will go before content-skeleton cells that display the day/week numbers
	rendernumberintrohtml: function(row) {
		var view = this.view;

		if (view.weeknumbersvisible) {
			return '' +
				'<td class="fc-week-number" ' + view.weeknumberstyleattr() + '>' +
					'<span>' + // needed for matchcellwidths
						this.getcelldate(row, 0).format('w') +
					'</span>' +
				'</td>';
		}

		return '';
	},


	// generates the html that goes before the day bg cells for each day-row
	renderbgintrohtml: function() {
		var view = this.view;

		if (view.weeknumbersvisible) {
			return '<td class="fc-week-number ' + view.widgetcontentclass + '" ' +
				view.weeknumberstyleattr() + '></td>';
		}

		return '';
	},


	// generates the html that goes before every other type of row generated by daygrid.
	// affects helper-skeleton and highlight-skeleton rows.
	renderintrohtml: function() {
		var view = this.view;

		if (view.weeknumbersvisible) {
			return '<td class="fc-week-number" ' + view.weeknumberstyleattr() + '></td>';
		}

		return '';
	}

};

;;

/* a month view with day cells running in rows (one-per-week) and columns
----------------------------------------------------------------------------------------------------------------------*/

var monthview = fc.monthview = basicview.extend({

	// produces information about what range to display
	computerange: function(date) {
		var range = basicview.prototype.computerange.call(this, date); // get value from super-method
		var rowcnt;

		// ensure 6 weeks
		if (this.isfixedweeks()) {
			rowcnt = math.ceil(range.end.diff(range.start, 'weeks', true)); // could be partial weeks due to hiddendays
			range.end.add(6 - rowcnt, 'weeks');
		}

		return range;
	},


	// overrides the default basicview behavior to have special multi-week auto-height logic
	setgridheight: function(height, isauto) {

		isauto = isauto || this.opt('weekmode') === 'variable'; // legacy: weekmode is deprecated

		// if auto, make the height of each row the height that it would be if there were 6 weeks
		if (isauto) {
			height *= this.rowcnt / 6;
		}

		distributeheight(this.daygrid.rowels, height, !isauto); // if auto, don't compensate for height-hogging rows
	},


	isfixedweeks: function() {
		var weekmode = this.opt('weekmode'); // legacy: weekmode is deprecated
		if (weekmode) {
			return weekmode === 'fixed'; // if any other type of weekmode, assume not fixed
		}

		return this.opt('fixedweekcount');
	}

});

;;

fcviews.basic = {
	'class': basicview
};

fcviews.basicday = {
	type: 'basic',
	duration: { days: 1 }
};

fcviews.basicweek = {
	type: 'basic',
	duration: { weeks: 1 }
};

fcviews.month = {
	'class': monthview,
	duration: { months: 1 }, // important for prev/next
	defaults: {
		fixedweekcount: true
	}
};
;;

/* an abstract class for all agenda-related views. displays one more columns with time slots running vertically.
----------------------------------------------------------------------------------------------------------------------*/
// is a manager for the timegrid subcomponent and possibly the daygrid subcomponent (if alldayslot is on).
// responsible for managing width/height.

var agendaview = fc.agendaview = view.extend({

	timegridclass: timegrid, // class used to instantiate the timegrid. subclasses can override
	timegrid: null, // the main time-grid subcomponent of this view

	daygridclass: daygrid, // class used to instantiate the daygrid. subclasses can override
	daygrid: null, // the "all-day" subcomponent. if all-day is turned off, this will be null

	axiswidth: null, // the width of the time axis running down the side

	headcontainerel: null, // div that hold's the timegrid's rendered date header
	noscrollrowels: null, // set of fake row elements that must compensate when scrollerel has scrollbars

	// when the time-grid isn't tall enough to occupy the given height, we render an <hr> underneath
	bottomruleel: null,
	bottomruleheight: null,


	initialize: function() {
		this.timegrid = this.instantiatetimegrid();

		if (this.opt('alldayslot')) { // should we display the "all-day" area?
			this.daygrid = this.instantiatedaygrid(); // the all-day subcomponent of this view
		}
	},


	// instantiates the timegrid object this view needs. draws from this.timegridclass
	instantiatetimegrid: function() {
		var subclass = this.timegridclass.extend(agendatimegridmethods);

		return new subclass(this);
	},


	// instantiates the daygrid object this view might need. draws from this.daygridclass
	instantiatedaygrid: function() {
		var subclass = this.daygridclass.extend(agendadaygridmethods);

		return new subclass(this);
	},


	/* rendering
	------------------------------------------------------------------------------------------------------------------*/


	// sets the display range and computes all necessary dates
	setrange: function(range) {
		view.prototype.setrange.call(this, range); // call the super-method

		this.timegrid.setrange(range);
		if (this.daygrid) {
			this.daygrid.setrange(range);
		}
	},


	// renders the view into `this.el`, which has already been assigned
	renderdates: function() {

		this.el.addclass('fc-agenda-view').html(this.renderskeletonhtml());
		this.renderhead();

		// the element that wraps the time-grid that will probably scroll
		this.scrollerel = this.el.find('.fc-time-grid-container');

		this.timegrid.setelement(this.el.find('.fc-time-grid'));
		this.timegrid.renderdates();

		// the <hr> that sometimes displays under the time-grid
		this.bottomruleel = $('<hr class="fc-divider ' + this.widgetheaderclass + '"/>')
			.appendto(this.timegrid.el); // inject it into the time-grid

		if (this.daygrid) {
			this.daygrid.setelement(this.el.find('.fc-day-grid'));
			this.daygrid.renderdates();

			// have the day-grid extend it's coordinate area over the <hr> dividing the two grids
			this.daygrid.bottomcoordpadding = this.daygrid.el.next('hr').outerheight();
		}

		this.noscrollrowels = this.el.find('.fc-row:not(.fc-scroller *)'); // fake rows not within the scroller
	},


	// render the day-of-week headers
	renderhead: function() {
		this.headcontainerel =
			this.el.find('.fc-head-container')
				.html(this.timegrid.renderheadhtml());
	},


	// unrenders the content of the view. since we haven't separated skeleton rendering from date rendering,
	// always completely kill each grid's rendering.
	unrenderdates: function() {
		this.timegrid.unrenderdates();
		this.timegrid.removeelement();

		if (this.daygrid) {
			this.daygrid.unrenderdates();
			this.daygrid.removeelement();
		}
	},


	// builds the html skeleton for the view.
	// the day-grid and time-grid components will render inside containers defined by this html.
	renderskeletonhtml: function() {
		return '' +
			'<table>' +
				'<thead class="fc-head">' +
					'<tr>' +
						'<td class="fc-head-container ' + this.widgetheaderclass + '"></td>' +
					'</tr>' +
				'</thead>' +
				'<tbody class="fc-body">' +
					'<tr>' +
						'<td class="' + this.widgetcontentclass + '">' +
							(this.daygrid ?
								'<div class="fc-day-grid"/>' +
								'<hr class="fc-divider ' + this.widgetheaderclass + '"/>' :
								''
								) +
							'<div class="fc-time-grid-container">' +
								'<div class="fc-time-grid"/>' +
							'</div>' +
						'</td>' +
					'</tr>' +
				'</tbody>' +
			'</table>';
	},


	// generates an html attribute string for setting the width of the axis, if it is known
	axisstyleattr: function() {
		if (this.axiswidth !== null) {
			 return 'style="width:' + this.axiswidth + 'px"';
		}
		return '';
	},


	/* business hours
	------------------------------------------------------------------------------------------------------------------*/


	renderbusinesshours: function() {
		this.timegrid.renderbusinesshours();

		if (this.daygrid) {
			this.daygrid.renderbusinesshours();
		}
	},


	unrenderbusinesshours: function() {
		this.timegrid.unrenderbusinesshours();

		if (this.daygrid) {
			this.daygrid.unrenderbusinesshours();
		}
	},


	/* now indicator
	------------------------------------------------------------------------------------------------------------------*/


	getnowindicatorunit: function() {
		return this.timegrid.getnowindicatorunit();
	},


	rendernowindicator: function(date) {
		this.timegrid.rendernowindicator(date);
	},


	unrendernowindicator: function() {
		this.timegrid.unrendernowindicator();
	},


	/* dimensions
	------------------------------------------------------------------------------------------------------------------*/


	updatesize: function(isresize) {
		this.timegrid.updatesize(isresize);

		view.prototype.updatesize.call(this, isresize); // call the super-method
	},


	// refreshes the horizontal dimensions of the view
	updatewidth: function() {
		// make all axis cells line up, and record the width so newly created axis cells will have it
		this.axiswidth = matchcellwidths(this.el.find('.fc-axis'));
	},


	// adjusts the vertical dimensions of the view to the specified values
	setheight: function(totalheight, isauto) {
		var eventlimit;
		var scrollerheight;

		if (this.bottomruleheight === null) {
			// calculate the height of the rule the very first time
			this.bottomruleheight = this.bottomruleel.outerheight();
		}
		this.bottomruleel.hide(); // .show() will be called later if this <hr> is necessary

		// reset all dimensions back to the original state
		this.scrollerel.css('overflow', '');
		unsetscroller(this.scrollerel);
		uncompensatescroll(this.noscrollrowels);

		// limit number of events in the all-day area
		if (this.daygrid) {
			this.daygrid.removesegpopover(); // kill the "more" popover if displayed

			eventlimit = this.opt('eventlimit');
			if (eventlimit && typeof eventlimit !== 'number') {
				eventlimit = agenda_all_day_event_limit; // make sure "auto" goes to a real number
			}
			if (eventlimit) {
				this.daygrid.limitrows(eventlimit);
			}
		}

		if (!isauto) { // should we force dimensions of the scroll container, or let the contents be natural height?

			scrollerheight = this.computescrollerheight(totalheight);
			if (setpotentialscroller(this.scrollerel, scrollerheight)) { // using scrollbars?

				// make the all-day and header rows lines up
				compensatescroll(this.noscrollrowels, getscrollbarwidths(this.scrollerel));

				// the scrollbar compensation might have changed text flow, which might affect height, so recalculate
				// and reapply the desired height to the scroller.
				scrollerheight = this.computescrollerheight(totalheight);
				this.scrollerel.height(scrollerheight);
			}
			else { // no scrollbars
				// still, force a height and display the bottom rule (marks the end of day)
				this.scrollerel.height(scrollerheight).css('overflow', 'hidden'); // in case <hr> goes outside
				this.bottomruleel.show();
			}
		}
	},


	// computes the initial pre-configured scroll state prior to allowing the user to change it
	computeinitialscroll: function() {
		var scrolltime = moment.duration(this.opt('scrolltime'));
		var top = this.timegrid.computetimetop(scrolltime);

		// zoom can give weird floating-point values. rather scroll a little bit further
		top = math.ceil(top);

		if (top) {
			top++; // to overcome top border that slots beyond the first have. looks better
		}

		return top;
	},


	/* hit areas
	------------------------------------------------------------------------------------------------------------------*/
	// forward all hit-related method calls to the grids (daygrid might not be defined)


	preparehits: function() {
		this.timegrid.preparehits();
		if (this.daygrid) {
			this.daygrid.preparehits();
		}
	},


	releasehits: function() {
		this.timegrid.releasehits();
		if (this.daygrid) {
			this.daygrid.releasehits();
		}
	},


	queryhit: function(left, top) {
		var hit = this.timegrid.queryhit(left, top);

		if (!hit && this.daygrid) {
			hit = this.daygrid.queryhit(left, top);
		}

		return hit;
	},


	gethitspan: function(hit) {
		// todo: hit.component is set as a hack to identify where the hit came from
		return hit.component.gethitspan(hit);
	},


	gethitel: function(hit) {
		// todo: hit.component is set as a hack to identify where the hit came from
		return hit.component.gethitel(hit);
	},


	/* events
	------------------------------------------------------------------------------------------------------------------*/


	// renders events onto the view and populates the view's segment array
	renderevents: function(events) {
		var dayevents = [];
		var timedevents = [];
		var daysegs = [];
		var timedsegs;
		var i;

		// separate the events into all-day and timed
		for (i = 0; i < events.length; i++) {
			if (events[i].allday) {
				dayevents.push(events[i]);
			}
			else {
				timedevents.push(events[i]);
			}
		}

		// render the events in the subcomponents
		timedsegs = this.timegrid.renderevents(timedevents);
		if (this.daygrid) {
			daysegs = this.daygrid.renderevents(dayevents);
		}

		// the all-day area is flexible and might have a lot of events, so shift the height
		this.updateheight();
	},


	// retrieves all segment objects that are rendered in the view
	geteventsegs: function() {
		return this.timegrid.geteventsegs().concat(
			this.daygrid ? this.daygrid.geteventsegs() : []
		);
	},


	// unrenders all event elements and clears internal segment data
	unrenderevents: function() {

		// unrender the events in the subcomponents
		this.timegrid.unrenderevents();
		if (this.daygrid) {
			this.daygrid.unrenderevents();
		}

		// we don't need to call updateheight() because:
		// a) a renderevents() call always happens after this, which will eventually call updateheight()
		// b) in ie8, this causes a flash whenever events are rerendered
	},


	/* dragging (for events and external elements)
	------------------------------------------------------------------------------------------------------------------*/


	// a returned value of `true` signals that a mock "helper" event has been rendered.
	renderdrag: function(droplocation, seg) {
		if (droplocation.start.hastime()) {
			return this.timegrid.renderdrag(droplocation, seg);
		}
		else if (this.daygrid) {
			return this.daygrid.renderdrag(droplocation, seg);
		}
	},


	unrenderdrag: function() {
		this.timegrid.unrenderdrag();
		if (this.daygrid) {
			this.daygrid.unrenderdrag();
		}
	},


	/* selection
	------------------------------------------------------------------------------------------------------------------*/


	// renders a visual indication of a selection
	renderselection: function(span) {
		if (span.start.hastime() || span.end.hastime()) {
			this.timegrid.renderselection(span);
		}
		else if (this.daygrid) {
			this.daygrid.renderselection(span);
		}
	},


	// unrenders a visual indications of a selection
	unrenderselection: function() {
		this.timegrid.unrenderselection();
		if (this.daygrid) {
			this.daygrid.unrenderselection();
		}
	}

});


// methods that will customize the rendering behavior of the agendaview's timegrid
// todo: move into timegrid
var agendatimegridmethods = {


	// generates the html that will go before the day-of week header cells
	renderheadintrohtml: function() {
		var view = this.view;
		var weektext;

		if (view.opt('weeknumbers')) {
			weektext = this.start.format(view.opt('smallweekformat'));

			return '' +
				'<th class="fc-axis fc-week-number ' + view.widgetheaderclass + '" ' + view.axisstyleattr() + '>' +
					'<span>' + // needed for matchcellwidths
						htmlescape(weektext) +
					'</span>' +
				'</th>';
		}
		else {
			return '<th class="fc-axis ' + view.widgetheaderclass + '" ' + view.axisstyleattr() + '></th>';
		}
	},


	// generates the html that goes before the bg of the timegrid slot area. long vertical column.
	renderbgintrohtml: function() {
		var view = this.view;

		return '<td class="fc-axis ' + view.widgetcontentclass + '" ' + view.axisstyleattr() + '></td>';
	},


	// generates the html that goes before all other types of cells.
	// affects content-skeleton, helper-skeleton, highlight-skeleton for both the time-grid and day-grid.
	renderintrohtml: function() {
		var view = this.view;

		return '<td class="fc-axis" ' + view.axisstyleattr() + '></td>';
	}

};


// methods that will customize the rendering behavior of the agendaview's daygrid
var agendadaygridmethods = {


	// generates the html that goes before the all-day cells
	renderbgintrohtml: function() {
		var view = this.view;

		return '' +
			'<td class="fc-axis ' + view.widgetcontentclass + '" ' + view.axisstyleattr() + '>' +
				'<span>' + // needed for matchcellwidths
					(view.opt('alldayhtml') || htmlescape(view.opt('alldaytext'))) +
				'</span>' +
			'</td>';
	},


	// generates the html that goes before all other types of cells.
	// affects content-skeleton, helper-skeleton, highlight-skeleton for both the time-grid and day-grid.
	renderintrohtml: function() {
		var view = this.view;

		return '<td class="fc-axis" ' + view.axisstyleattr() + '></td>';
	}

};

;;

var agenda_all_day_event_limit = 5;

// potential nice values for the slot-duration and interval-duration
// from largest to smallest
var agenda_stock_sub_durations = [
	{ hours: 1 },
	{ minutes: 30 },
	{ minutes: 15 },
	{ seconds: 30 },
	{ seconds: 15 }
];

fcviews.agenda = {
	'class': agendaview,
	defaults: {
		alldayslot: true,
		alldaytext: 'all-day',
		slotduration: '00:30:00',
		mintime: '00:00:00',
		maxtime: '24:00:00',
		sloteventoverlap: true // a bad name. confused with overlap/constraint system
	}
};

fcviews.agendaday = {
	type: 'agenda',
	duration: { days: 1 }
};

fcviews.agendaweek = {
	type: 'agenda',
	duration: { weeks: 1 }
};
;;

return fc; // export for node/commonjs
});