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YUI.add('yui2-json', function(Y) {

    var YAHOO    = Y.YUI2;

    /*

Copyright (c) 2011, Yahoo! Inc. All rights reserved.

Code licensed under the BSD License:

http://developer.yahoo.com/yui/license.html

version: 2.9.0

*/

/**

 * Provides methods to parse JSON strings and convert objects to JSON strings.

 *

 * @module json

 * @class JSON

 * @namespace YAHOO.lang

 * @static

 */

(function () {

var l = YAHOO.lang,

    isFunction = l.isFunction,

    isObject   = l.isObject,

    isArray    = l.isArray,

    _toStr     = Object.prototype.toString,

                 // 'this' is the global object.  window in browser env.  Keep

                 // the code env agnostic.  Caja requies window, unfortunately.

    Native     = (YAHOO.env.ua.caja ? window : this).JSON,

/* Variables used by parse */

    /**

     * Replace certain Unicode characters that JavaScript may handle incorrectly

     * during eval--either by deleting them or treating them as line

     * endings--with escape sequences.

     * IMPORTANT NOTE: This regex will be used to modify the input if a match is

     * found.

     *

     * @property _UNICODE_EXCEPTIONS

     * @type {RegExp}

     * @private

     */

    _UNICODE_EXCEPTIONS = /[\u0000\u00ad\u0600-\u0604\u070f\u17b4\u17b5\u200c-\u200f\u2028-\u202f\u2060-\u206f\ufeff\ufff0-\uffff]/g,

    /**

     * First step in the safety evaluation.  Regex used to replace all escape

     * sequences (i.e. "\\", etc) with '@' characters (a non-JSON character).

     *

     * @property _ESCAPES

     * @type {RegExp}

     * @static

     * @private

     */

    _ESCAPES = /\\(?:["\\\/bfnrt]|u[0-9a-fA-F]{4})/g,

    /**

     * Second step in the safety evaluation.  Regex used to replace all simple

     * values with ']' characters.

     *

     * @property _VALUES

     * @type {RegExp}

     * @static

     * @private

     */

    _VALUES  = /"[^"\\\n\r]*"|true|false|null|-?\d+(?:\.\d*)?(?:[eE][+\-]?\d+)?/g,

    /**

     * Third step in the safety evaluation.  Regex used to remove all open

     * square brackets following a colon, comma, or at the beginning of the

     * string.

     *

     * @property _BRACKETS

     * @type {RegExp}

     * @static

     * @private

     */

    _BRACKETS = /(?:^|:|,)(?:\s*\[)+/g,

    /**

     * Final step in the safety evaluation.  Regex used to test the string left

     * after all previous replacements for invalid characters.

     *

     * @property _UNSAFE

     * @type {RegExp}

     * @static

     * @private

     */

    _UNSAFE  = /[^\],:{}\s]/,

/* Variables used by stringify */

    /**

     * Regex used to replace special characters in strings for JSON

     * stringification.

     *

     * @property _SPECIAL_CHARS

     * @type {RegExp}

     * @static

     * @private

     */

    _SPECIAL_CHARS = /[\\\"\x00-\x1f\x7f-\x9f\u00ad\u0600-\u0604\u070f\u17b4\u17b5\u200c-\u200f\u2028-\u202f\u2060-\u206f\ufeff\ufff0-\uffff]/g,

    /**

     * Character substitution map for common escapes and special characters.

     *

     * @property _CHARS

     * @type {Object}

     * @static

     * @private

     */

    _CHARS = {

        '\b': '\\b',

        '\t': '\\t',

        '\n': '\\n',

        '\f': '\\f',

        '\r': '\\r',

        '"' : '\\"',

        '\\': '\\\\'

    },

    UNDEFINED = 'undefined',

    OBJECT    = 'object',

    NULL      = 'null',

    STRING    = 'string',

    NUMBER    = 'number',

    BOOLEAN   = 'boolean',

    DATE      = 'date',

    _allowable = {

        'undefined'        : UNDEFINED,

        'string'           : STRING,

        '[object String]'  : STRING,

        'number'           : NUMBER,

        '[object Number]'  : NUMBER,

        'boolean'          : BOOLEAN,

        '[object Boolean]' : BOOLEAN,

        '[object Date]'    : DATE,

        '[object RegExp]'  : OBJECT

    },

    EMPTY     = '',

    OPEN_O    = '{',

    CLOSE_O   = '}',

    OPEN_A    = '[',

    CLOSE_A   = ']',

    COMMA     = ',',

    COMMA_CR  = ",\n",

    CR        = "\n",

    COLON     = ':',

    COLON_SP  = ': ',

    QUOTE     = '"';

// Only accept JSON objects that report a [[Class]] of JSON

Native = _toStr.call(Native) === '[object JSON]' && Native;

// Escapes a special character to a safe Unicode representation

function _char(c) {

    if (!_CHARS[c]) {

        _CHARS[c] =  '\\u'+('0000'+(+(c.charCodeAt(0))).toString(16)).slice(-4);

    }

    return _CHARS[c];

}

/* functions used by parse */

/**

 * Traverses nested objects, applying a filter or reviver function to

 * each value.  The value returned from the function will replace the

 * original value in the key:value pair.  If the value returned is

 * undefined, the key will be omitted from the returned object.

 *

 * @method _revive

 * @param data {MIXED} Any JavaScript data

 * @param reviver {Function} filter or mutation function

 * @return {MIXED} The results of the filtered/mutated data structure

 * @private

 */

function _revive(data, reviver) {

    var walk = function (o,key) {

        var k,v,value = o[key];

        if (value && typeof value === 'object') {

            for (k in value) {

                if (l.hasOwnProperty(value,k)) {

                    v = walk(value, k);

                    if (v === undefined) {

                        delete value[k];

                    } else {

                        value[k] = v;

                    }

                }

            }

        }

        return reviver.call(o,key,value);

    };

    return typeof reviver === 'function' ? walk({'':data},'') : data;

}

/**

 * Replace certain Unicode characters that may be handled incorrectly by

 * some browser implementations.

 *

 * @method _prepare

 * @param s {String} parse input

 * @return {String} sanitized JSON string ready to be validated/parsed

 * @private

 */

function _prepare(s) {

    return s.replace(_UNICODE_EXCEPTIONS, _char);

}

function _isSafe(str) {

    return l.isString(str) &&

            !_UNSAFE.test(str.replace(_ESCAPES,'@').

                             replace(_VALUES,']').

                             replace(_BRACKETS,''));

}

function _parse(s,reviver) {

    // sanitize

    s = _prepare(s);

    // Ensure valid JSON

    if (_isSafe(s)) {

        // Eval the text into a JavaScript data structure, apply the

        // reviver function if provided, and return

        return _revive( eval('(' + s + ')'), reviver );

    }

    // The text is not valid JSON

    throw new SyntaxError('JSON.parse');

}

/* functions used by stringify */

// Utility function used to determine how to serialize a variable.

function _type(o) {

    var t = typeof o;

    return  _allowable[t] ||              // number, string, boolean, undefined

            _allowable[_toStr.call(o)] || // Number, String, Boolean, Date

            (t === OBJECT ?

                (o ? OBJECT : NULL) :     // object, array, null, misc natives

                UNDEFINED);               // function, unknown

}

// Enclose escaped strings in quotes

function _string(s) {

    return QUOTE + s.replace(_SPECIAL_CHARS, _char) + QUOTE;

}

// Adds the provided space to the beginning of every line in the input string

function _indent(s,space) {

    return s.replace(/^/gm, space);

}

// JavaScript implementation of stringify (see API declaration of stringify)

function _stringify(o,w,space) {

    if (o === undefined) {

        return undefined;

    }

    var replacer = isFunction(w) ? w : null,

        format   = _toStr.call(space).match(/String|Number/) || [],

        _date    = YAHOO.lang.JSON.dateToString,

        stack    = [],

        tmp,i,len;

    if (replacer || !isArray(w)) {

        w = undefined;

    }

    // Ensure whitelist keys are unique (bug 2110391)

    if (w) {

        tmp = {};

        for (i = 0, len = w.length; i < len; ++i) {

            tmp[w[i]] = true;

        }

        w = tmp;

    }

    // Per the spec, strings are truncated to 10 characters and numbers

    // are converted to that number of spaces (max 10)

    space = format[0] === 'Number' ?

                new Array(Math.min(Math.max(0,space),10)+1).join(" ") :

                (space || EMPTY).slice(0,10);

    function _serialize(h,key) {

        var value = h[key],

            t     = _type(value),

            a     = [],

            colon = space ? COLON_SP : COLON,

            arr, i, keys, k, v;

        // Per the ECMA 5 spec, toJSON is applied before the replacer is

        // called.  Also per the spec, Date.prototype.toJSON has been added, so

        // Date instances should be serialized prior to exposure to the

        // replacer.  I disagree with this decision, but the spec is the spec.

        if (isObject(value) && isFunction(value.toJSON)) {

            value = value.toJSON(key);

        } else if (t === DATE) {

            value = _date(value);

        }

        if (isFunction(replacer)) {

            value = replacer.call(h,key,value);

        }

        if (value !== h[key]) {

            t = _type(value);

        }

        switch (t) {

            case DATE    : // intentional fallthrough.  Pre-replacer Dates are

                           // serialized in the toJSON stage.  Dates here would

                           // have been produced by the replacer.

            case OBJECT  : break;

            case STRING  : return _string(value);

            case NUMBER  : return isFinite(value) ? value+EMPTY : NULL;

            case BOOLEAN : return value+EMPTY;

            case NULL    : return NULL;

            default      : return undefined;

        }

        // Check for cyclical references in nested objects

        for (i = stack.length - 1; i >= 0; --i) {

            if (stack[i] === value) {

                throw new Error("JSON.stringify. Cyclical reference");

            }

        }

        arr = isArray(value);

        // Add the object to the processing stack

        stack.push(value);

        if (arr) { // Array

            for (i = value.length - 1; i >= 0; --i) {

                a[i] = _serialize(value, i) || NULL;

            }

        } else {   // Object

            // If whitelist provided, take only those keys

            keys = w || value;

            i = 0;

            for (k in keys) {

                if (l.hasOwnProperty(keys, k)) {

                    v = _serialize(value, k);

                    if (v) {

                        a[i++] = _string(k) + colon + v;

                    }

                }

            }

        }

        // remove the array from the stack

        stack.pop();

        if (space && a.length) {

            return arr ?

                OPEN_A + CR + _indent(a.join(COMMA_CR), space) + CR + CLOSE_A :

                OPEN_O + CR + _indent(a.join(COMMA_CR), space) + CR + CLOSE_O;

        } else {

            return arr ?

                OPEN_A + a.join(COMMA) + CLOSE_A :

                OPEN_O + a.join(COMMA) + CLOSE_O;

        }

    }

    // process the input

    return _serialize({'':o},'');

}

/* Public API */

YAHOO.lang.JSON = {

    /**

     * Leverage native JSON parse if the browser has a native implementation.

     * In general, this is a good idea.  See the Known Issues section in the

     * JSON user guide for caveats.  The default value is true for browsers with

     * native JSON support.

     *

     * @property useNativeParse

     * @type Boolean

     * @default true

     * @static

     */

    useNativeParse : !!Native,

    /**

     * Leverage native JSON stringify if the browser has a native

     * implementation.  In general, this is a good idea.  See the Known Issues

     * section in the JSON user guide for caveats.  The default value is true

     * for browsers with native JSON support.

     *

     * @property useNativeStringify

     * @type Boolean

     * @default true

     * @static

     */

    useNativeStringify : !!Native,

    /**

     * Four step determination whether a string is safe to eval. In three steps,

     * escape sequences, safe values, and properly placed open square brackets

     * are replaced with placeholders or removed.  Then in the final step, the

     * result of all these replacements is checked for invalid characters.

     *

     * @method isSafe

     * @param str {String} JSON string to be tested

     * @return {boolean} is the string safe for eval?

     * @static

     */

    isSafe : function (s) {

        return _isSafe(_prepare(s));

    },

    /**

     * <p>Parse a JSON string, returning the native JavaScript

     * representation.</p>

     *

     * <p>When lang.JSON.useNativeParse is true, this will defer to the native

     * JSON.parse if the browser has a native implementation.  Otherwise, a

     * JavaScript implementation based on http://www.json.org/json2.js

     * is used.</p>

     *

     * @method parse

     * @param s {string} JSON string data

     * @param reviver {function} (optional) function(k,v) passed each key:value

     *          pair of object literals, allowing pruning or altering values

     * @return {MIXED} the native JavaScript representation of the JSON string

     * @throws SyntaxError

     * @static

     */

    parse : function (s,reviver) {

        if (typeof s !== 'string') {

            s += '';

        }

        return Native && YAHOO.lang.JSON.useNativeParse ?

            Native.parse(s,reviver) : _parse(s,reviver);

    },

    /**

     * <p>Converts an arbitrary value to a JSON string representation.</p>

     *

     * <p>Objects with cyclical references will trigger an exception.</p>

     *

     * <p>If a whitelist is provided, only matching object keys will be

     * included.  Alternately, a replacer function may be passed as the

     * second parameter.  This function is executed on every value in the

     * input, and its return value will be used in place of the original value.

     * This is useful to serialize specialized objects or class instances.</p>

     *

     * <p>If a positive integer or non-empty string is passed as the third

     * parameter, the output will be formatted with carriage returns and

     * indentation for readability.  If a String is passed (such as "\t") it

     * will be used once for each indentation level.  If a number is passed,

     * that number of spaces will be used.</p>

     *

     * <p>When lang.JSON.useNativeStringify is true, this will defer to the

     * native JSON.stringify if the browser has a native implementation.

     * Otherwise, a JavaScript implementation is used.</p>

     *

     * @method stringify

     * @param o {MIXED} any arbitrary object to convert to JSON string

     * @param w {Array|Function} (optional) whitelist of acceptable object keys

     *                  to include OR a function(value,key) to alter values

     *                  before serialization

     * @param space {Number|String} (optional) indentation character(s) or

     *                  depthy of spaces to format the output

     * @return {string} JSON string representation of the input

     * @throws Error

     * @static

     */

    stringify : function (o,w,space) {

        return Native && YAHOO.lang.JSON.useNativeStringify ?

            Native.stringify(o,w,space) : _stringify(o,w,space);

    },

    /**

     * Serializes a Date instance as a UTC date string.  Used internally by

     * the JavaScript implementation of stringify.  If you need a different

     * Date serialization format, override this method.  If you change this,

     * you should also set useNativeStringify to false, since native JSON

     * implementations serialize Dates per the ECMAScript 5 spec.  You've been

     * warned.

     *

     * @method dateToString

     * @param d {Date} The Date to serialize

     * @return {String} stringified Date in UTC format YYYY-MM-DDTHH:mm:SSZ

     * @static

     */

    dateToString : function (d) {

        function _zeroPad(v) {

            return v < 10 ? '0' + v : v;

        }

        return d.getUTCFullYear()         + '-' +

            _zeroPad(d.getUTCMonth() + 1) + '-' +

            _zeroPad(d.getUTCDate())      + 'T' +

            _zeroPad(d.getUTCHours())     + COLON +

            _zeroPad(d.getUTCMinutes())   + COLON +

            _zeroPad(d.getUTCSeconds())   + 'Z';

    },

    /**

     * Reconstitute Date instances from the default JSON UTC serialization.

     * Reference this from a reviver function to rebuild Dates during the

     * parse operation.

     *

     * @method stringToDate

     * @param str {String} String serialization of a Date

     * @return {Date}

     */

    stringToDate : function (str) {

        var m = str.match(/^(\d{4})-(\d{2})-(\d{2})T(\d{2}):(\d{2}):(\d{2})(?:\.(\d{3}))?Z$/);

        if (m) {

            var d = new Date();

            d.setUTCFullYear(m[1], m[2]-1, m[3]);

            d.setUTCHours(m[4], m[5], m[6], (m[7] || 0));

            return d;

        }

        return str;

    }

};

/**

 * <p>Four step determination whether a string is safe to eval. In three steps,

 * escape sequences, safe values, and properly placed open square brackets

 * are replaced with placeholders or removed.  Then in the final step, the

 * result of all these replacements is checked for invalid characters.</p>

 *

 * <p>This is an alias for isSafe.</p>

 *

 * @method isValid

 * @param str {String} JSON string to be tested

 * @return {boolean} is the string safe for eval?

 * @static

 * @deprecated use isSafe

 */

YAHOO.lang.JSON.isValid = YAHOO.lang.JSON.isSafe;

})();

YAHOO.register("json", YAHOO.lang.JSON, {version: "2.9.0", build: "2800"});

}, '2.9.0' ,{"requires": ["yui2-yahoo"]});