From 8f3142b761bad3b8411ba6b5ad4be72bb4ed87b5 Mon Sep 17 00:00:00 2001
From: Alan Knowles <alan@akbkhome.com>
Date: Mon, 12 Sep 2011 10:18:31 +0800
Subject: [PATCH] Date.js

---
 Date.js | 804 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 804 insertions(+)
 create mode 100644 Date.js

diff --git a/Date.js b/Date.js
new file mode 100644
index 00000000..88904904
--- /dev/null
+++ b/Date.js
@@ -0,0 +1,804 @@
+/*
+ * Based on:
+ * Ext JS Library 1.1.1
+ * Copyright(c) 2006-2007, Ext JS, LLC.
+ *
+ * Originally Released Under LGPL - original licence link has changed is not relivant.
+ *
+ * Fork - LGPL
+ * <script type="text/javascript">
+ */
+
+/**
+ * @class Date
+ *
+ * The date parsing and format syntax is a subset of
+ * <a href="http://www.php.net/date">PHP's date() function</a>, and the formats that are
+ * supported will provide results equivalent to their PHP versions.
+ *
+ * Following is the list of all currently supported formats:
+ *<pre>
+Sample date:
+'Wed Jan 10 2007 15:05:01 GMT-0600 (Central Standard Time)'
+
+Format  Output      Description
+------  ----------  --------------------------------------------------------------
+  d      10         Day of the month, 2 digits with leading zeros
+  D      Wed        A textual representation of a day, three letters
+  j      10         Day of the month without leading zeros
+  l      Wednesday  A full textual representation of the day of the week
+  S      th         English ordinal day of month suffix, 2 chars (use with j)
+  w      3          Numeric representation of the day of the week
+  z      9          The julian date, or day of the year (0-365)
+  W      01         ISO-8601 2-digit week number of year, weeks starting on Monday (00-52)
+  F      January    A full textual representation of the month
+  m      01         Numeric representation of a month, with leading zeros
+  M      Jan        Month name abbreviation, three letters
+  n      1          Numeric representation of a month, without leading zeros
+  t      31         Number of days in the given month
+  L      0          Whether it's a leap year (1 if it is a leap year, else 0)
+  Y      2007       A full numeric representation of a year, 4 digits
+  y      07         A two digit representation of a year
+  a      pm         Lowercase Ante meridiem and Post meridiem
+  A      PM         Uppercase Ante meridiem and Post meridiem
+  g      3          12-hour format of an hour without leading zeros
+  G      15         24-hour format of an hour without leading zeros
+  h      03         12-hour format of an hour with leading zeros
+  H      15         24-hour format of an hour with leading zeros
+  i      05         Minutes with leading zeros
+  s      01         Seconds, with leading zeros
+  O      -0600      Difference to Greenwich time (GMT) in hours
+  P      -06:00     Difference to Greenwich time (GMT) with colon between hours and minutes
+  T      CST        Timezone setting of the machine running the code
+  Z      -21600     Timezone offset in seconds (negative if west of UTC, positive if east)
+</pre>
+ *
+ * Example usage (note that you must escape format specifiers with '\\' to render them as character literals):
+ * <pre><code>
+var dt = new Date('1/10/2007 03:05:01 PM GMT-0600');
+document.write(dt.format('Y-m-d'));                         //2007-01-10
+document.write(dt.format('F j, Y, g:i a'));                 //January 10, 2007, 3:05 pm
+document.write(dt.format('l, \\t\\he dS of F Y h:i:s A'));  //Wednesday, the 10th of January 2007 03:05:01 PM
+ </code></pre>
+ *
+ * Here are some standard date/time patterns that you might find helpful.  They
+ * are not part of the source of Date.js, but to use them you can simply copy this
+ * block of code into any script that is included after Date.js and they will also become
+ * globally available on the Date object.  Feel free to add or remove patterns as needed in your code.
+ * <pre><code>
+Date.patterns = {
+    ISO8601Long:"Y-m-d H:i:s",
+    ISO8601Short:"Y-m-d",
+    ShortDate: "n/j/Y",
+    LongDate: "l, F d, Y",
+    FullDateTime: "l, F d, Y g:i:s A",
+    MonthDay: "F d",
+    ShortTime: "g:i A",
+    LongTime: "g:i:s A",
+    SortableDateTime: "Y-m-d\\TH:i:s",
+    UniversalSortableDateTime: "Y-m-d H:i:sO",
+    YearMonth: "F, Y"
+};
+</code></pre>
+ *
+ * Example usage:
+ * <pre><code>
+var dt = new Date();
+document.write(dt.format(Date.patterns.ShortDate));
+ </code></pre>
+ */
+
+/*
+ * Most of the date-formatting functions below are the excellent work of Baron Schwartz.
+ * They generate precompiled functions from date formats instead of parsing and
+ * processing the pattern every time you format a date.  These functions are available
+ * on every Date object (any javascript function).
+ *
+ * The original article and download are here:
+ * http://www.xaprb.com/blog/2005/12/12/javascript-closures-for-runtime-efficiency/
+ *
+ */
+ 
+ 
+ // was in core
+/**
+ Returns the number of milliseconds between this date and date
+ @param {Date} date (optional) Defaults to now
+ @return {Number} The diff in milliseconds
+ @member Date getElapsed
+ */
+Date.prototype.getElapsed = function(date) {
+	return Math.abs((date || new Date()).getTime()-this.getTime());
+};
+// was in date file..
+
+
+// private
+Date.parseFunctions = {count:0};
+// private
+Date.parseRegexes = [];
+// private
+Date.formatFunctions = {count:0};
+
+// private
+Date.prototype.dateFormat = function(format) {
+    if (Date.formatFunctions[format] == null) {
+        Date.createNewFormat(format);
+    }
+    var func = Date.formatFunctions[format];
+    return this[func]();
+};
+
+
+/**
+ * Formats a date given the supplied format string
+ * @param {String} format The format string
+ * @return {String} The formatted date
+ * @method
+ */
+Date.prototype.format = Date.prototype.dateFormat;
+
+// private
+Date.createNewFormat = function(format) {
+    var funcName = "format" + Date.formatFunctions.count++;
+    Date.formatFunctions[format] = funcName;
+    var code = "Date.prototype." + funcName + " = function(){return ";
+    var special = false;
+    var ch = '';
+    for (var i = 0; i < format.length; ++i) {
+        ch = format.charAt(i);
+        if (!special && ch == "\\") {
+            special = true;
+        }
+        else if (special) {
+            special = false;
+            code += "'" + String.escape(ch) + "' + ";
+        }
+        else {
+            code += Date.getFormatCode(ch);
+        }
+    }
+    /** eval:var:zzzzzzzzzzzzz */
+    eval(code.substring(0, code.length - 3) + ";}");
+};
+
+// private
+Date.getFormatCode = function(character) {
+    switch (character) {
+    case "d":
+        return "String.leftPad(this.getDate(), 2, '0') + ";
+    case "D":
+        return "Date.dayNames[this.getDay()].substring(0, 3) + ";
+    case "j":
+        return "this.getDate() + ";
+    case "l":
+        return "Date.dayNames[this.getDay()] + ";
+    case "S":
+        return "this.getSuffix() + ";
+    case "w":
+        return "this.getDay() + ";
+    case "z":
+        return "this.getDayOfYear() + ";
+    case "W":
+        return "this.getWeekOfYear() + ";
+    case "F":
+        return "Date.monthNames[this.getMonth()] + ";
+    case "m":
+        return "String.leftPad(this.getMonth() + 1, 2, '0') + ";
+    case "M":
+        return "Date.monthNames[this.getMonth()].substring(0, 3) + ";
+    case "n":
+        return "(this.getMonth() + 1) + ";
+    case "t":
+        return "this.getDaysInMonth() + ";
+    case "L":
+        return "(this.isLeapYear() ? 1 : 0) + ";
+    case "Y":
+        return "this.getFullYear() + ";
+    case "y":
+        return "('' + this.getFullYear()).substring(2, 4) + ";
+    case "a":
+        return "(this.getHours() < 12 ? 'am' : 'pm') + ";
+    case "A":
+        return "(this.getHours() < 12 ? 'AM' : 'PM') + ";
+    case "g":
+        return "((this.getHours() % 12) ? this.getHours() % 12 : 12) + ";
+    case "G":
+        return "this.getHours() + ";
+    case "h":
+        return "String.leftPad((this.getHours() % 12) ? this.getHours() % 12 : 12, 2, '0') + ";
+    case "H":
+        return "String.leftPad(this.getHours(), 2, '0') + ";
+    case "i":
+        return "String.leftPad(this.getMinutes(), 2, '0') + ";
+    case "s":
+        return "String.leftPad(this.getSeconds(), 2, '0') + ";
+    case "O":
+        return "this.getGMTOffset() + ";
+    case "P":
+    	return "this.getGMTColonOffset() + ";
+    case "T":
+        return "this.getTimezone() + ";
+    case "Z":
+        return "(this.getTimezoneOffset() * -60) + ";
+    default:
+        return "'" + String.escape(character) + "' + ";
+    }
+};
+
+/**
+ * Parses the passed string using the specified format. Note that this function expects dates in normal calendar
+ * format, meaning that months are 1-based (1 = January) and not zero-based like in JavaScript dates.  Any part of
+ * the date format that is not specified will default to the current date value for that part.  Time parts can also
+ * be specified, but default to 0.  Keep in mind that the input date string must precisely match the specified format
+ * string or the parse operation will fail.
+ * Example Usage:
+<pre><code>
+//dt = Fri May 25 2007 (current date)
+var dt = new Date();
+
+//dt = Thu May 25 2006 (today's month/day in 2006)
+dt = Date.parseDate("2006", "Y");
+
+//dt = Sun Jan 15 2006 (all date parts specified)
+dt = Date.parseDate("2006-1-15", "Y-m-d");
+
+//dt = Sun Jan 15 2006 15:20:01 GMT-0600 (CST)
+dt = Date.parseDate("2006-1-15 3:20:01 PM", "Y-m-d h:i:s A" );
+</code></pre>
+ * @param {String} input The unparsed date as a string
+ * @param {String} format The format the date is in
+ * @return {Date} The parsed date
+ * @static
+ */
+Date.parseDate = function(input, format) {
+    if (Date.parseFunctions[format] == null) {
+        Date.createParser(format);
+    }
+    var func = Date.parseFunctions[format];
+    return Date[func](input);
+};
+/**
+ * @private
+ */
+Date.createParser = function(format) {
+    var funcName = "parse" + Date.parseFunctions.count++;
+    var regexNum = Date.parseRegexes.length;
+    var currentGroup = 1;
+    Date.parseFunctions[format] = funcName;
+
+    var code = "Date." + funcName + " = function(input){\n"
+        + "var y = -1, m = -1, d = -1, h = -1, i = -1, s = -1, o, z, v;\n"
+        + "var d = new Date();\n"
+        + "y = d.getFullYear();\n"
+        + "m = d.getMonth();\n"
+        + "d = d.getDate();\n"
+        + "var results = input.match(Date.parseRegexes[" + regexNum + "]);\n"
+        + "if (results && results.length > 0) {";
+    var regex = "";
+
+    var special = false;
+    var ch = '';
+    for (var i = 0; i < format.length; ++i) {
+        ch = format.charAt(i);
+        if (!special && ch == "\\") {
+            special = true;
+        }
+        else if (special) {
+            special = false;
+            regex += String.escape(ch);
+        }
+        else {
+            var obj = Date.formatCodeToRegex(ch, currentGroup);
+            currentGroup += obj.g;
+            regex += obj.s;
+            if (obj.g && obj.c) {
+                code += obj.c;
+            }
+        }
+    }
+
+    code += "if (y >= 0 && m >= 0 && d > 0 && h >= 0 && i >= 0 && s >= 0)\n"
+        + "{v = new Date(y, m, d, h, i, s);}\n"
+        + "else if (y >= 0 && m >= 0 && d > 0 && h >= 0 && i >= 0)\n"
+        + "{v = new Date(y, m, d, h, i);}\n"
+        + "else if (y >= 0 && m >= 0 && d > 0 && h >= 0)\n"
+        + "{v = new Date(y, m, d, h);}\n"
+        + "else if (y >= 0 && m >= 0 && d > 0)\n"
+        + "{v = new Date(y, m, d);}\n"
+        + "else if (y >= 0 && m >= 0)\n"
+        + "{v = new Date(y, m);}\n"
+        + "else if (y >= 0)\n"
+        + "{v = new Date(y);}\n"
+        + "}return (v && (z || o))?\n" // favour UTC offset over GMT offset
+        + "    ((z)? v.add(Date.SECOND, (v.getTimezoneOffset() * 60) + (z*1)) :\n" // reset to UTC, then add offset
+        + "        v.add(Date.HOUR, (v.getGMTOffset() / 100) + (o / -100))) : v\n" // reset to GMT, then add offset
+        + ";}";
+
+    Date.parseRegexes[regexNum] = new RegExp("^" + regex + "$");
+    /** eval:var:zzzzzzzzzzzzz */
+    eval(code);
+};
+
+// private
+Date.formatCodeToRegex = function(character, currentGroup) {
+    switch (character) {
+    case "D":
+        return {g:0,
+        c:null,
+        s:"(?:Sun|Mon|Tue|Wed|Thu|Fri|Sat)"};
+    case "j":
+        return {g:1,
+            c:"d = parseInt(results[" + currentGroup + "], 10);\n",
+            s:"(\\d{1,2})"}; // day of month without leading zeroes
+    case "d":
+        return {g:1,
+            c:"d = parseInt(results[" + currentGroup + "], 10);\n",
+            s:"(\\d{2})"}; // day of month with leading zeroes
+    case "l":
+        return {g:0,
+            c:null,
+            s:"(?:" + Date.dayNames.join("|") + ")"};
+    case "S":
+        return {g:0,
+            c:null,
+            s:"(?:st|nd|rd|th)"};
+    case "w":
+        return {g:0,
+            c:null,
+            s:"\\d"};
+    case "z":
+        return {g:0,
+            c:null,
+            s:"(?:\\d{1,3})"};
+    case "W":
+        return {g:0,
+            c:null,
+            s:"(?:\\d{2})"};
+    case "F":
+        return {g:1,
+            c:"m = parseInt(Date.monthNumbers[results[" + currentGroup + "].substring(0, 3)], 10);\n",
+            s:"(" + Date.monthNames.join("|") + ")"};
+    case "M":
+        return {g:1,
+            c:"m = parseInt(Date.monthNumbers[results[" + currentGroup + "]], 10);\n",
+            s:"(Jan|Feb|Mar|Apr|May|Jun|Jul|Aug|Sep|Oct|Nov|Dec)"};
+    case "n":
+        return {g:1,
+            c:"m = parseInt(results[" + currentGroup + "], 10) - 1;\n",
+            s:"(\\d{1,2})"}; // Numeric representation of a month, without leading zeros
+    case "m":
+        return {g:1,
+            c:"m = parseInt(results[" + currentGroup + "], 10) - 1;\n",
+            s:"(\\d{2})"}; // Numeric representation of a month, with leading zeros
+    case "t":
+        return {g:0,
+            c:null,
+            s:"\\d{1,2}"};
+    case "L":
+        return {g:0,
+            c:null,
+            s:"(?:1|0)"};
+    case "Y":
+        return {g:1,
+            c:"y = parseInt(results[" + currentGroup + "], 10);\n",
+            s:"(\\d{4})"};
+    case "y":
+        return {g:1,
+            c:"var ty = parseInt(results[" + currentGroup + "], 10);\n"
+                + "y = ty > Date.y2kYear ? 1900 + ty : 2000 + ty;\n",
+            s:"(\\d{1,2})"};
+    case "a":
+        return {g:1,
+            c:"if (results[" + currentGroup + "] == 'am') {\n"
+                + "if (h == 12) { h = 0; }\n"
+                + "} else { if (h < 12) { h += 12; }}",
+            s:"(am|pm)"};
+    case "A":
+        return {g:1,
+            c:"if (results[" + currentGroup + "] == 'AM') {\n"
+                + "if (h == 12) { h = 0; }\n"
+                + "} else { if (h < 12) { h += 12; }}",
+            s:"(AM|PM)"};
+    case "g":
+    case "G":
+        return {g:1,
+            c:"h = parseInt(results[" + currentGroup + "], 10);\n",
+            s:"(\\d{1,2})"}; // 12/24-hr format  format of an hour without leading zeroes
+    case "h":
+    case "H":
+        return {g:1,
+            c:"h = parseInt(results[" + currentGroup + "], 10);\n",
+            s:"(\\d{2})"}; //  12/24-hr format  format of an hour with leading zeroes
+    case "i":
+        return {g:1,
+            c:"i = parseInt(results[" + currentGroup + "], 10);\n",
+            s:"(\\d{2})"};
+    case "s":
+        return {g:1,
+            c:"s = parseInt(results[" + currentGroup + "], 10);\n",
+            s:"(\\d{2})"};
+    case "O":
+        return {g:1,
+            c:[
+                "o = results[", currentGroup, "];\n",
+                "var sn = o.substring(0,1);\n", // get + / - sign
+                "var hr = o.substring(1,3)*1 + Math.floor(o.substring(3,5) / 60);\n", // get hours (performs minutes-to-hour conversion also)
+                "var mn = o.substring(3,5) % 60;\n", // get minutes
+                "o = ((-12 <= (hr*60 + mn)/60) && ((hr*60 + mn)/60 <= 14))?\n", // -12hrs <= GMT offset <= 14hrs
+                "    (sn + String.leftPad(hr, 2, 0) + String.leftPad(mn, 2, 0)) : null;\n"
+            ].join(""),
+            s:"([+\-]\\d{4})"};
+    case "P":
+    	return {g:1,
+    		c:[
+    		   "o = results[", currentGroup, "];\n",
+    		   "var sn = o.substring(0,1);\n",
+    		   "var hr = o.substring(1,3)*1 + Math.floor(o.substring(4,6) / 60);\n",
+    		   "var mn = o.substring(4,6) % 60;\n",
+    		   "o = ((-12 <= (hr*60 + mn)/60) && ((hr*60 + mn)/60 <= 14))?\n",
+    	                "    (sn + String.leftPad(hr, 2, 0) + String.leftPad(mn, 2, 0)) : null;\n"
+            ].join(""),
+            s:"([+\-]\\d{4})"};
+    case "T":
+        return {g:0,
+            c:null,
+            s:"[A-Z]{1,4}"}; // timezone abbrev. may be between 1 - 4 chars
+    case "Z":
+        return {g:1,
+            c:"z = results[" + currentGroup + "];\n" // -43200 <= UTC offset <= 50400
+                  + "z = (-43200 <= z*1 && z*1 <= 50400)? z : null;\n",
+            s:"([+\-]?\\d{1,5})"}; // leading '+' sign is optional for UTC offset
+    default:
+        return {g:0,
+            c:null,
+            s:String.escape(character)};
+    }
+};
+
+/**
+ * Get the timezone abbreviation of the current date (equivalent to the format specifier 'T').
+ * @return {String} The abbreviated timezone name (e.g. 'CST')
+ */
+Date.prototype.getTimezone = function() {
+    return this.toString().replace(/^.*? ([A-Z]{1,4})[\-+][0-9]{4} .*$/, "$1");
+};
+
+/**
+ * Get the offset from GMT of the current date (equivalent to the format specifier 'O').
+ * @return {String} The 4-character offset string prefixed with + or - (e.g. '-0600')
+ */
+Date.prototype.getGMTOffset = function() {
+    return (this.getTimezoneOffset() > 0 ? "-" : "+")
+        + String.leftPad(Math.abs(Math.floor(this.getTimezoneOffset() / 60)), 2, "0")
+        + String.leftPad(this.getTimezoneOffset() % 60, 2, "0");
+};
+
+/**
+ * Get the offset from GMT of the current date (equivalent to the format specifier 'P').
+ * @return {String} 2-characters representing hours and 2-characters representing minutes
+ * seperated by a colon and prefixed with + or - (e.g. '-06:00')
+ */
+Date.prototype.getGMTColonOffset = function() {
+	return (this.getTimezoneOffset() > 0 ? "-" : "+")
+		+ String.leftPad(Math.abs(Math.floor(this.getTimezoneOffset() / 60)), 2, "0")
+		+ ":"
+		+ String.leftPad(this.getTimezoneOffset() %60, 2, "0");
+}
+
+/**
+ * Get the numeric day number of the year, adjusted for leap year.
+ * @return {Number} 0 through 364 (365 in leap years)
+ */
+Date.prototype.getDayOfYear = function() {
+    var num = 0;
+    Date.daysInMonth[1] = this.isLeapYear() ? 29 : 28;
+    for (var i = 0; i < this.getMonth(); ++i) {
+        num += Date.daysInMonth[i];
+    }
+    return num + this.getDate() - 1;
+};
+
+/**
+ * Get the string representation of the numeric week number of the year
+ * (equivalent to the format specifier 'W').
+ * @return {String} '00' through '52'
+ */
+Date.prototype.getWeekOfYear = function() {
+    // Skip to Thursday of this week
+    var now = this.getDayOfYear() + (4 - this.getDay());
+    // Find the first Thursday of the year
+    var jan1 = new Date(this.getFullYear(), 0, 1);
+    var then = (7 - jan1.getDay() + 4);
+    return String.leftPad(((now - then) / 7) + 1, 2, "0");
+};
+
+/**
+ * Whether or not the current date is in a leap year.
+ * @return {Boolean} True if the current date is in a leap year, else false
+ */
+Date.prototype.isLeapYear = function() {
+    var year = this.getFullYear();
+    return ((year & 3) == 0 && (year % 100 || (year % 400 == 0 && year)));
+};
+
+/**
+ * Get the first day of the current month, adjusted for leap year.  The returned value
+ * is the numeric day index within the week (0-6) which can be used in conjunction with
+ * the {@link #monthNames} array to retrieve the textual day name.
+ * Example:
+ *<pre><code>
+var dt = new Date('1/10/2007');
+document.write(Date.dayNames[dt.getFirstDayOfMonth()]); //output: 'Monday'
+</code></pre>
+ * @return {Number} The day number (0-6)
+ */
+Date.prototype.getFirstDayOfMonth = function() {
+    var day = (this.getDay() - (this.getDate() - 1)) % 7;
+    return (day < 0) ? (day + 7) : day;
+};
+
+/**
+ * Get the last day of the current month, adjusted for leap year.  The returned value
+ * is the numeric day index within the week (0-6) which can be used in conjunction with
+ * the {@link #monthNames} array to retrieve the textual day name.
+ * Example:
+ *<pre><code>
+var dt = new Date('1/10/2007');
+document.write(Date.dayNames[dt.getLastDayOfMonth()]); //output: 'Wednesday'
+</code></pre>
+ * @return {Number} The day number (0-6)
+ */
+Date.prototype.getLastDayOfMonth = function() {
+    var day = (this.getDay() + (Date.daysInMonth[this.getMonth()] - this.getDate())) % 7;
+    return (day < 0) ? (day + 7) : day;
+};
+
+
+/**
+ * Get the first date of this date's month
+ * @return {Date}
+ */
+Date.prototype.getFirstDateOfMonth = function() {
+    return new Date(this.getFullYear(), this.getMonth(), 1);
+};
+
+/**
+ * Get the last date of this date's month
+ * @return {Date}
+ */
+Date.prototype.getLastDateOfMonth = function() {
+    return new Date(this.getFullYear(), this.getMonth(), this.getDaysInMonth());
+};
+/**
+ * Get the number of days in the current month, adjusted for leap year.
+ * @return {Number} The number of days in the month
+ */
+Date.prototype.getDaysInMonth = function() {
+    Date.daysInMonth[1] = this.isLeapYear() ? 29 : 28;
+    return Date.daysInMonth[this.getMonth()];
+};
+
+/**
+ * Get the English ordinal suffix of the current day (equivalent to the format specifier 'S').
+ * @return {String} 'st, 'nd', 'rd' or 'th'
+ */
+Date.prototype.getSuffix = function() {
+    switch (this.getDate()) {
+        case 1:
+        case 21:
+        case 31:
+            return "st";
+        case 2:
+        case 22:
+            return "nd";
+        case 3:
+        case 23:
+            return "rd";
+        default:
+            return "th";
+    }
+};
+
+// private
+Date.daysInMonth = [31,28,31,30,31,30,31,31,30,31,30,31];
+
+/**
+ * An array of textual month names.
+ * Override these values for international dates, for example...
+ * Date.monthNames = ['JanInYourLang', 'FebInYourLang', ...];
+ * @type Array
+ * @static
+ */
+Date.monthNames =
+   ["January",
+    "February",
+    "March",
+    "April",
+    "May",
+    "June",
+    "July",
+    "August",
+    "September",
+    "October",
+    "November",
+    "December"];
+
+/**
+ * An array of textual day names.
+ * Override these values for international dates, for example...
+ * Date.dayNames = ['SundayInYourLang', 'MondayInYourLang', ...];
+ * @type Array
+ * @static
+ */
+Date.dayNames =
+   ["Sunday",
+    "Monday",
+    "Tuesday",
+    "Wednesday",
+    "Thursday",
+    "Friday",
+    "Saturday"];
+
+// private
+Date.y2kYear = 50;
+// private
+Date.monthNumbers = {
+    Jan:0,
+    Feb:1,
+    Mar:2,
+    Apr:3,
+    May:4,
+    Jun:5,
+    Jul:6,
+    Aug:7,
+    Sep:8,
+    Oct:9,
+    Nov:10,
+    Dec:11};
+
+/**
+ * Creates and returns a new Date instance with the exact same date value as the called instance.
+ * Dates are copied and passed by reference, so if a copied date variable is modified later, the original
+ * variable will also be changed.  When the intention is to create a new variable that will not
+ * modify the original instance, you should create a clone.
+ *
+ * Example of correctly cloning a date:
+ * <pre><code>
+//wrong way:
+var orig = new Date('10/1/2006');
+var copy = orig;
+copy.setDate(5);
+document.write(orig);  //returns 'Thu Oct 05 2006'!
+
+//correct way:
+var orig = new Date('10/1/2006');
+var copy = orig.clone();
+copy.setDate(5);
+document.write(orig);  //returns 'Thu Oct 01 2006'
+</code></pre>
+ * @return {Date} The new Date instance
+ */
+Date.prototype.clone = function() {
+	return new Date(this.getTime());
+};
+
+/**
+ * Clears any time information from this date
+ @param {Boolean} clone true to create a clone of this date, clear the time and return it
+ @return {Date} this or the clone
+ */
+Date.prototype.clearTime = function(clone){
+    if(clone){
+        return this.clone().clearTime();
+    }
+    this.setHours(0);
+    this.setMinutes(0);
+    this.setSeconds(0);
+    this.setMilliseconds(0);
+    return this;
+};
+
+// private
+// safari setMonth is broken
+if(Roo.isSafari){
+    Date.brokenSetMonth = Date.prototype.setMonth;
+	Date.prototype.setMonth = function(num){
+		if(num <= -1){
+			var n = Math.ceil(-num);
+			var back_year = Math.ceil(n/12);
+			var month = (n % 12) ? 12 - n % 12 : 0 ;
+			this.setFullYear(this.getFullYear() - back_year);
+			return Date.brokenSetMonth.call(this, month);
+		} else {
+			return Date.brokenSetMonth.apply(this, arguments);
+		}
+	};
+}
+
+/** Date interval constant 
+* @static 
+* @type String */
+Date.MILLI = "ms";
+/** Date interval constant 
+* @static 
+* @type String */
+Date.SECOND = "s";
+/** Date interval constant 
+* @static 
+* @type String */
+Date.MINUTE = "mi";
+/** Date interval constant 
+* @static 
+* @type String */
+Date.HOUR = "h";
+/** Date interval constant 
+* @static 
+* @type String */
+Date.DAY = "d";
+/** Date interval constant 
+* @static 
+* @type String */
+Date.MONTH = "mo";
+/** Date interval constant 
+* @static 
+* @type String */
+Date.YEAR = "y";
+
+/**
+ * Provides a convenient method of performing basic date arithmetic.  This method
+ * does not modify the Date instance being called - it creates and returns
+ * a new Date instance containing the resulting date value.
+ *
+ * Examples:
+ * <pre><code>
+//Basic usage:
+var dt = new Date('10/29/2006').add(Date.DAY, 5);
+document.write(dt); //returns 'Fri Oct 06 2006 00:00:00'
+
+//Negative values will subtract correctly:
+var dt2 = new Date('10/1/2006').add(Date.DAY, -5);
+document.write(dt2); //returns 'Tue Sep 26 2006 00:00:00'
+
+//You can even chain several calls together in one line!
+var dt3 = new Date('10/1/2006').add(Date.DAY, 5).add(Date.HOUR, 8).add(Date.MINUTE, -30);
+document.write(dt3); //returns 'Fri Oct 06 2006 07:30:00'
+ </code></pre>
+ *
+ * @param {String} interval   A valid date interval enum value
+ * @param {Number} value      The amount to add to the current date
+ * @return {Date} The new Date instance
+ */
+Date.prototype.add = function(interval, value){
+  var d = this.clone();
+  if (!interval || value === 0) return d;
+  switch(interval.toLowerCase()){
+    case Date.MILLI:
+      d.setMilliseconds(this.getMilliseconds() + value);
+      break;
+    case Date.SECOND:
+      d.setSeconds(this.getSeconds() + value);
+      break;
+    case Date.MINUTE:
+      d.setMinutes(this.getMinutes() + value);
+      break;
+    case Date.HOUR:
+      d.setHours(this.getHours() + value);
+      break;
+    case Date.DAY:
+      d.setDate(this.getDate() + value);
+      break;
+    case Date.MONTH:
+      var day = this.getDate();
+      if(day > 28){
+          day = Math.min(day, this.getFirstDateOfMonth().add('mo', value).getLastDateOfMonth().getDate());
+      }
+      d.setDate(day);
+      d.setMonth(this.getMonth() + value);
+      break;
+    case Date.YEAR:
+      d.setFullYear(this.getFullYear() + value);
+      break;
+  }
+  return d;
+};
-- 
2.39.2