File: vendors/datejs/src/core/parser.js

(function () {
	var $D = Date;

	/**
	 * @desc Converts the specified string value into its JavaScript Date equivalent using CultureInfo specific format information.
	 * 
	 * Example
	<pre><code>
	///////////
	// Dates //
	///////////

	// 15-Oct-2004
	var d1 = Date.parse("10/15/2004");

	// 15-Oct-2004
	var d1 = Date.parse("15-Oct-2004");

	// 15-Oct-2004
	var d1 = Date.parse("2004.10.15");

	//Fri Oct 15, 2004
	var d1 = Date.parse("Fri Oct 15, 2004");

	///////////
	// Times //
	///////////

	// Today at 10 PM.
	var d1 = Date.parse("10 PM");

	// Today at 10:30 PM.
	var d1 = Date.parse("10:30 P.M.");

	// Today at 6 AM.
	var d1 = Date.parse("06am");

	/////////////////////
	// Dates and Times //
	/////////////////////

	// 8-July-2004 @ 10:30 PM
	var d1 = Date.parse("July 8th, 2004, 10:30 PM");

	// 1-July-2004 @ 10:30 PM
	var d1 = Date.parse("2004-07-01T22:30:00");

	////////////////////
	// Relative Dates //
	////////////////////

	// Returns today's date. The string "today" is culture specific.
	var d1 = Date.parse("today");

	// Returns yesterday's date. The string "yesterday" is culture specific.
	var d1 = Date.parse("yesterday");

	// Returns the date of the next thursday.
	var d1 = Date.parse("Next thursday");

	// Returns the date of the most previous monday.
	var d1 = Date.parse("last monday");

	// Returns today's day + one year.
	var d1 = Date.parse("next year");

	///////////////
	// Date Math //
	///////////////

	// Today + 2 days
	var d1 = Date.parse("t+2");

	// Today + 2 days
	var d1 = Date.parse("today + 2 days");

	// Today + 3 months
	var d1 = Date.parse("t+3m");

	// Today - 1 year
	var d1 = Date.parse("today - 1 year");

	// Today - 1 year
	var d1 = Date.parse("t-1y"); 


	/////////////////////////////
	// Partial Dates and Times //
	/////////////////////////////

	// July 15th of this year.
	var d1 = Date.parse("July 15");

	// 15th day of current day and year.
	var d1 = Date.parse("15");

	// July 1st of current year at 10pm.
	var d1 = Date.parse("7/1 10pm");
	</code></pre>
	 *
	 * @param {String}   The string value to convert into a Date object [Required]
	 * @return {Date}    A Date object or null if the string cannot be converted into a Date.
	 */
	var parseUtils = {
		removeOrds: function (s) {
			ords = s.match(/\b(\d+)(?:st|nd|rd|th)\b/); // find ordinal matches
			s = ((ords && ords.length === 2) ? s.replace(ords[0], ords[1]) : s);
			return s;
		},
		grammarParser: function (s) {
			var r = null;
			try {
				r = $D.Grammar.start.call({}, s.replace(/^\s*(\S*(\s+\S+)*)\s*$/, "$1"));
			} catch (e) {
				return null;
			}
			
			return ((r[1].length === 0) ? r[0] : null);
		},
		nativeFallback: function(s) {
			var t;
			try {
				// ok we haven't parsed it, last ditch attempt with the built-in parser.
				t = Date._parse(s);
				return (t || t === 0) ? new Date(t) : null;
			} catch (e) {
				return null;
			}
		}
	};
	function parse (s) {
		var d;
		if (!s) {
			return null;
		}
		if (s instanceof Date) {
			return s.clone();
		}
		if (s.length >= 4 && s.charAt(0) !== "0" && s.charAt(0) !== "+"&& s.charAt(0) !== "-") { // ie: 2004 will pass, 0800 won't.
			//  Start with specific formats
			d = $D.Parsing.ISO.parse(s) || $D.Parsing.Numeric.parse(s);
		}
		if (d instanceof Date && !isNaN(d.getTime())) {
			return d;
		} else {
			// find ordinal dates (1st, 3rd, 8th, etc and remove them as they cause parsing issues)
			s = $D.Parsing.Normalizer.parse(parseUtils.removeOrds(s));
			d = parseUtils.grammarParser(s);
			if (d !== null) {
				return d;
			} else {
				return parseUtils.nativeFallback(s);
			}
		}
	}

	if (!$D._parse) {
		$D._parse = $D.parse;
	}
	$D.parse = parse;

	Date.getParseFunction = function (fx) {
		var fns = Date.Grammar.allformats(fx);
		return function (s) {
			var r = null;
			for (var i = 0; i < fns.length; i++) {
				try {
					r = fns[i].call({}, s);
				} catch (e) {
					continue;
				}
				if (r[1].length === 0) {
					return r[0];
				}
			}
			return null;
		};
	};
	
	/**
	 * Converts the specified string value into its JavaScript Date equivalent using the specified format {String} or formats {Array} and the CultureInfo specific format information.
	 * The format of the string value must match one of the supplied formats exactly.
	 * 
	 * Example
	<pre><code>
	// 15-Oct-2004
	var d1 = Date.parseExact("10/15/2004", "M/d/yyyy");

	// 15-Oct-2004
	var d1 = Date.parse("15-Oct-2004", "M-ddd-yyyy");

	// 15-Oct-2004
	var d1 = Date.parse("2004.10.15", "yyyy.MM.dd");

	// Multiple formats
	var d1 = Date.parseExact("10/15/2004", ["M/d/yyyy", "MMMM d, yyyy"]);
	</code></pre>
	 *
	 * @param {String}   The string value to convert into a Date object [Required].
	 * @param {Object}   The expected format {String} or an array of expected formats {Array} of the date string [Required].
	 * @return {Date}    A Date object or null if the string cannot be converted into a Date.
	 */
	$D.parseExact = function (s, fx) {
		return $D.getParseFunction(fx)(s);
	};
}());