/* Date Math
-----------------------------------------------------------------------------*/

var DAY_MS = 86400000,
	HOUR_MS = 3600000,
	MINUTE_MS = 60000;

function addYears(d, n, keepTime) {
	d.setFullYear(d.getFullYear() + n);
	if (!keepTime) {
		clearTime(d);
	}
	return d;
}

function addMonths(d, n, keepTime) { // prevents day overflow/underflow
	if (+d) { // prevent infinite looping on invalid dates
		var m = d.getMonth() + n,
			check = cloneDate(d);
		check.setDate(1);
		check.setMonth(m);
		d.setMonth(m);
		if (!keepTime) {
			clearTime(d);
		}
		while (d.getMonth() != check.getMonth()) {
			d.setDate(d.getDate() + (d < check ? 1 : -1));
		}
	}
	return d;
}

function addDays(d, n, keepTime) { // deals with daylight savings
	if (+d) {
		var dd = d.getDate() + n,
			check = cloneDate(d);
		check.setHours(9); // set to middle of day
		check.setDate(dd);
		d.setDate(dd);
		if (!keepTime) {
			clearTime(d);
		}
		fixDate(d, check);
	}
	return d;
}
fc.addDays = addDays;

function fixDate(d, check) { // force d to be on check's YMD, for daylight savings purposes
	if (+d) { // prevent infinite looping on invalid dates
		while (d.getDate() != check.getDate()) {
			d.setTime(+d + (d < check ? 1 : -1) * HOUR_MS);
		}
	}
}

function addMinutes(d, n) {
	d.setMinutes(d.getMinutes() + n);
	return d;
}

function clearTime(d) {
	d.setHours(0);
	d.setMinutes(0);
	d.setSeconds(0); 
	d.setMilliseconds(0);
	return d;
}

function cloneDate(d, dontKeepTime) {
	if (dontKeepTime) {
		return clearTime(new Date(+d));
	}
	return new Date(+d);
}

function zeroDate() { // returns a Date with time 00:00:00 and dateOfMonth=1
	var i=0, d;
	do {
		d = new Date(1970, i++, 1);
	} while (d.getHours() != 0);
	return d;
}

function skipWeekend(date, inc, excl) {
	inc = inc || 1;
	while (date.getDay()==0 || (excl && date.getDay()==1 || !excl && date.getDay()==6)) {
		addDays(date, inc);
	}
	return date;
}



/* Date Parsing
-----------------------------------------------------------------------------*/

var parseDate = fc.parseDate = function(s) {
	if (typeof s == 'object') { // already a Date object
		return s;
	}
	if (typeof s == 'number') { // a UNIX timestamp
		return new Date(s * 1000);
	}
	if (typeof s == 'string') {
		if (s.match(/^\d+$/)) { // a UNIX timestamp
			return new Date(parseInt(s) * 1000);
		}
		return parseISO8601(s, true) || (s ? new Date(s) : null);
	}
	// TODO: never return invalid dates (like from new Date(<string>)), return null instead
	return null;
}

var parseISO8601 = fc.parseISO8601 = function(s, ignoreTimezone) {
	// derived from http://delete.me.uk/2005/03/iso8601.html
	// TODO: for a know glitch/feature, read tests/issue_206_parseDate_dst.html
	var m = s.match(/^([0-9]{4})(-([0-9]{2})(-([0-9]{2})([T ]([0-9]{2}):([0-9]{2})(:([0-9]{2})(\.([0-9]+))?)?(Z|(([-+])([0-9]{2}):([0-9]{2})))?)?)?)?$/);
	if (!m) {
		return null;
	}
	var date = new Date(m[1], 0, 1),
		check = new Date(m[1], 0, 1, 9, 0),
		offset = 0;
	if (m[3]) {
		date.setMonth(m[3] - 1);
		check.setMonth(m[3] - 1);
	}
	if (m[5]) {
		date.setDate(m[5]);
		check.setDate(m[5]);
	}
	fixDate(date, check);
	if (m[7]) {
		date.setHours(m[7]);
	}
	if (m[8]) {
		date.setMinutes(m[8]);
	}
	if (m[10]) {
		date.setSeconds(m[10]);
	}
	if (m[12]) {
		date.setMilliseconds(Number("0." + m[12]) * 1000);
	}
	fixDate(date, check);
	if (!ignoreTimezone) {
		if (m[14]) {
			offset = Number(m[16]) * 60 + Number(m[17]);
			offset *= m[15] == '-' ? 1 : -1;
		}
		offset -= date.getTimezoneOffset();
	}
	return new Date(+date + (offset * 60 * 1000));
}

var parseTime = fc.parseTime = function(s) { // returns minutes since start of day
	if (typeof s == 'number') { // an hour
		return s * 60;
	}
	if (typeof s == 'object') { // a Date object
		return s.getHours() * 60 + s.getMinutes();
	}
	var m = s.match(/(\d+)(?::(\d+))?\s*(\w+)?/);
	if (m) {
		var h = parseInt(m[1]);
		if (m[3]) {
			h %= 12;
			if (m[3].toLowerCase().charAt(0) == 'p') {
				h += 12;
			}
		}
		return h * 60 + (m[2] ? parseInt(m[2]) : 0);
	}
};



/* Date Formatting
-----------------------------------------------------------------------------*/

var formatDate = fc.formatDate = function(date, format, options) {
	return formatDates(date, null, format, options);
}

var formatDates = fc.formatDates = function(date1, date2, format, options) {
	options = options || defaults;
	var date = date1,
		otherDate = date2,
		i, len = format.length, c,
		i2, formatter,
		res = '';
	for (i=0; i<len; i++) {
		c = format.charAt(i);
		if (c == "'") {
			for (i2=i+1; i2<len; i2++) {
				if (format.charAt(i2) == "'") {
					if (date) {
						if (i2 == i+1) {
							res += "'";
						}else{
							res += format.substring(i+1, i2);
						}
						i = i2;
					}
					break;
				}
			}
		}
		else if (c == '(') {
			for (i2=i+1; i2<len; i2++) {
				if (format.charAt(i2) == ')') {
					var subres = formatDate(date, format.substring(i+1, i2), options);
					if (parseInt(subres.replace(/\D/, ''))) {
						res += subres;
					}
					i = i2;
					break;
				}
			}
		}
		else if (c == '[') {
			for (i2=i+1; i2<len; i2++) {
				if (format.charAt(i2) == ']') {
					var subformat = format.substring(i+1, i2);
					var subres = formatDate(date, subformat, options);
					if (subres != formatDate(otherDate, subformat, options)) {
						res += subres;
					}
					i = i2;
					break;
				}
			}
		}
		else if (c == '{') {
			date = date2;
			otherDate = date1;
		}
		else if (c == '}') {
			date = date1;
			otherDate = date2;
		}
		else {
			for (i2=len; i2>i; i2--) {
				if (formatter = dateFormatters[format.substring(i, i2)]) {
					if (date) {
						res += formatter(date, options);
					}
					i = i2 - 1;
					break;
				}
			}
			if (i2 == i) {
				if (date) {
					res += c;
				}
			}
		}
	}
	return res;
}

var dateFormatters = {
	s	: function(d)	{ return d.getSeconds() },
	ss	: function(d)	{ return zeroPad(d.getSeconds()) },
	m	: function(d)	{ return d.getMinutes() },
	mm	: function(d)	{ return zeroPad(d.getMinutes()) },
	h	: function(d)	{ return d.getHours() % 12 || 12 },
	hh	: function(d)	{ return zeroPad(d.getHours() % 12 || 12) },
	H	: function(d)	{ return d.getHours() },
	HH	: function(d)	{ return zeroPad(d.getHours()) },
	d	: function(d)	{ return d.getDate() },
	dd	: function(d)	{ return zeroPad(d.getDate()) },
	ddd	: function(d,o)	{ return o.dayNamesShort[d.getDay()] },
	dddd: function(d,o)	{ return o.dayNames[d.getDay()] },
	M	: function(d)	{ return d.getMonth() + 1 },
	MM	: function(d)	{ return zeroPad(d.getMonth() + 1) },
	MMM	: function(d,o)	{ return o.monthNamesShort[d.getMonth()] },
	MMMM: function(d,o)	{ return o.monthNames[d.getMonth()] },
	yy	: function(d)	{ return (d.getFullYear()+'').substring(2) },
	yyyy: function(d)	{ return d.getFullYear() },
	t	: function(d)	{ return d.getHours() < 12 ? 'a' : 'p' },
	tt	: function(d)	{ return d.getHours() < 12 ? 'am' : 'pm' },
	T	: function(d)	{ return d.getHours() < 12 ? 'A' : 'P' },
	TT	: function(d)	{ return d.getHours() < 12 ? 'AM' : 'PM' },
	u	: function(d)	{ return formatDate(d, "yyyy-MM-dd'T'HH:mm:ss'Z'") },
	S	: function(d)	{
		var date = d.getDate();
		if (date > 10 && date < 20) return 'th';
		return ['st', 'nd', 'rd'][date%10-1] || 'th';
	}
};



/* Element Dimensions
-----------------------------------------------------------------------------*/

function setOuterWidth(element, width, includeMargins) {
	element.each(function(i, _element) {
		_element.style.width = width - hsides(_element, includeMargins) + 'px';
	});
}

function setOuterHeight(element, height, includeMargins) {
	element.each(function(i, _element) {
		_element.style.height = height - vsides(_element, includeMargins) + 'px';
	});
}


function hsides(_element, includeMargins) {
	return (parseFloat(jQuery.curCSS(_element, 'paddingLeft', true)) || 0) +
	       (parseFloat(jQuery.curCSS(_element, 'paddingRight', true)) || 0) +
	       (parseFloat(jQuery.curCSS(_element, 'borderLeftWidth', true)) || 0) +
	       (parseFloat(jQuery.curCSS(_element, 'borderRightWidth', true)) || 0) +
	       (includeMargins ? hmargins(_element) : 0);
}

function hmargins(_element) {
	return (parseFloat(jQuery.curCSS(_element, 'marginLeft', true)) || 0) +
	       (parseFloat(jQuery.curCSS(_element, 'marginRight', true)) || 0);
}

function vsides(_element, includeMargins) {
	return (parseFloat(jQuery.curCSS(_element, 'paddingTop', true)) || 0) +
	       (parseFloat(jQuery.curCSS(_element, 'paddingBottom', true)) || 0) +
	       (parseFloat(jQuery.curCSS(_element, 'borderTopWidth', true)) || 0) +
	       (parseFloat(jQuery.curCSS(_element, 'borderBottomWidth', true)) || 0) +
	       (includeMargins ? vmargins(_element) : 0);
}

function vmargins(_element) {
	return (parseFloat(jQuery.curCSS(_element, 'marginTop', true)) || 0) +
	       (parseFloat(jQuery.curCSS(_element, 'marginBottom', true)) || 0);
}



/* Position Calculation
-----------------------------------------------------------------------------*/
// nasty bugs in opera 9.25
// position()'s top returning incorrectly with TR/TD or elements within TD

var topBug;

function topCorrect(tr) { // tr/th/td or anything else
	if (topBug !== false) {
		var cell;
		if (tr.is('th,td')) {
			tr = (cell = tr).parent();
		}
		if (topBug == undefined && tr.is('tr')) {
			topBug = tr.position().top != tr.children().position().top;
		}
		if (topBug) {
			return tr.parent().position().top + (cell ? tr.position().top - cell.position().top : 0);
		}
	}
	return 0;
}



/* Hover Matrix
-----------------------------------------------------------------------------*/

function HoverMatrix(changeCallback) {

	var t=this,
		tops=[], lefts=[],
		prevRowE, prevColE,
		origRow, origCol,
		currRow, currCol;
	
	t.row = function(e) {
		prevRowE = $(e);
		tops.push(prevRowE.offset().top + topCorrect(prevRowE));
	};
	
	t.col = function(e) {
		prevColE = $(e);
		lefts.push(prevColE.offset().left);
	};

	t.mouse = function(x, y) {
		if (origRow == undefined) {
			tops.push(tops[tops.length-1] + prevRowE.outerHeight());
			lefts.push(lefts[lefts.length-1] + prevColE.outerWidth());
			currRow = currCol = -1;
		}
		var r, c;
		for (r=0; r<tops.length && y>=tops[r]; r++) ;
		for (c=0; c<lefts.length && x>=lefts[c]; c++) ;
		r = r >= tops.length ? -1 : r - 1;
		c = c >= lefts.length ? -1 : c - 1;
		if (r != currRow || c != currCol) {
			currRow = r;
			currCol = c;
			if (r == -1 || c == -1) {
				t.cell = null;
			}else{
				if (origRow == undefined) {
					origRow = r;
					origCol = c;
				}
				t.cell = {
					row: r,
					col: c,
					top: tops[r],
					left: lefts[c],
					width: lefts[c+1] - lefts[c],
					height: tops[r+1] - tops[r],
					isOrig: r==origRow && c==origCol,
					rowDelta: r-origRow,
					colDelta: c-origCol
				};
			}
			changeCallback(t.cell);
		}
	};

}



/* Misc Utils
-----------------------------------------------------------------------------*/

var undefined,
	dayIDs = ['sun', 'mon', 'tue', 'wed', 'thu', 'fri', 'sat'],
	arrayPop = Array.prototype.pop;

function zeroPad(n) {
	return (n < 10 ? '0' : '') + n;
}

function smartProperty(obj, name) { // get a camel-cased/namespaced property of an object
	if (obj[name] != undefined) {
		return obj[name];
	}
	var parts = name.split(/(?=[A-Z])/),
		i=parts.length-1, res;
	for (; i>=0; i--) {
		res = obj[parts[i].toLowerCase()];
		if (res != undefined) {
			return res;
		}
	}
	return obj[''];
}

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



function HorizontalPositionCache(getElement) {

	var t = this,
		elements = {},
		lefts = {},
		rights = {};
		
	function e(i) {
		return elements[i] =
			elements[i] || getElement(i);
	}
	
	t.left = function(i) {
		return lefts[i] =
			lefts[i] == undefined ? e(i).position().left : lefts[i];
	};
	
	t.right = function(i) {
		return rights[i] =
			rights[i] == undefined ? t.left(i) + e(i).width() : rights[i];
	};
	
	t.clear = function() {
		elements = {};
		lefts = {};
		rights = {};
	};
	
}