/*

Copyright (c) 2009, Yahoo! Inc. All rights reserved.

Code licensed under the BSD License:

http://developer.yahoo.net/yui/license.txt

version: 3.0.0b1

build: 1163

*/

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

/**

 * <p>The JSON module adds support for serializing JavaScript objects into

 * JSON strings and parsing JavaScript objects from strings in JSON format.</p>

 *

 * <p>The JSON namespace is added to your YUI instance including static methods

 * Y.JSON.parse(..) and Y.JSON.stringify(..).</p>

 *

 * <p>The functionality and method signatures follow the ECMAScript 5

 * specification.  In browsers with native JSON support, the native

 * implementation is used.</p>

 *

 * <p>The <code>json</code> module is a rollup of <code>json-parse</code> and

 * <code>json-stringify</code>.</p>

 * 

 * <p>As their names suggest, <code>json-parse</code> adds support for parsing

 * JSON data (Y.JSON.parse) and <code>json-stringify</code> for serializing

 * JavaScript data into JSON strings (Y.JSON.stringify).  You may choose to

 * include either of the submodules individually if you don't need the

 * complementary functionality, or include the rollup for both.</p>

 *

 * @module json

 * @class JSON

 * @static

 */

/**

 * Provides Y.JSON.parse method to accept JSON strings and return native

 * JavaScript objects.

 *

 * @module json

 * @submodule json-parse

 * @for JSON

 * @static

 */

// All internals kept private for security reasons

    /**

     * Alias to native browser implementation of the JSON object if available.

     *

     * @property Native

     * @type {Object}

     * @private

     */

var Native = Y.config.win.JSON,

    /**

     * 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}

     * @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}

     * @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}

     * @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 _INVALID

     * @type {RegExp}

     * @private

     */

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

    /**

     * Test for JSON string of simple data string, number, boolean, or null.

     * E.g. '"some string"', "true", "false", "null", or numbers "-123e+7"

     * This was needed for some WIP native implementations (FF3.1b2) but may be

     * unnecessary now.

     *

     * @property _SIMPLE

     * @type {RegExp}

     * @private

     */

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

    /**

     * Replaces specific unicode characters with their appropriate \unnnn

     * format. Some browsers ignore certain characters during eval.

     *

     * @method escapeException

     * @param c {String} Unicode character

     * @return {String} the \unnnn escapement of the character

     * @private

     */

    _escapeException = function (c) {

        return '\\u'+('0000'+(+(c.charCodeAt(0))).toString(16)).slice(-4);

    },

    /**

     * Traverses nested objects, applying a reviver function to each (key,value)

     * from the scope if the key:value's containing object.  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 data

     * @private

     */

    _revive = function (data, reviver) {

        var walk = function (o,key) {

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

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

                for (k in value) {

                    if (value.hasOwnProperty(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;

    },

    /**

     * Parse a JSON string, returning the native JavaScript representation.

     *

     * @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

     * @method parse

     * @static

     */

    // JavaScript implementation in lieu of native browser support.  Based on

    // the json2.js library from http://json.org

    _parse = function (s,reviver) {

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

            // Replace certain Unicode characters that are otherwise handled

            // incorrectly by some browser implementations.

            // NOTE: This modifies the input if such characters are found!

            s = s.replace(_UNICODE_EXCEPTIONS, _escapeException);

            // Test for any remaining invalid characters

            if (!_INVALID.test(s.replace(_ESCAPES,'@').

                                 replace(_VALUES,']').

                                 replace(_BRACKETS,''))) {

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

                // reviver function, and return

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

            }

        }

        throw new SyntaxError('JSON.parse');

    },

    test;

// Test the level of native browser support

if (Native && Object.prototype.toString.call(Native) === '[object JSON]') {

    try {

        test = Native.parse('{"x":1}', function (k,v) {return k=='x' ? 2 : v;});

        switch (test.x) {

            case 1 : // Reviver not supported

                _parse = function (s,reviver) {

                    return _SIMPLE.test(s) ?

                            eval('(' + s + ')') :

                            _revive(Native.parse(s), reviver);

                };

                break;

            case 2 : // Full support

                _parse = function (s, reviver) {

                    return Native.parse(s, reviver);

                };

                break;

            // default is JS implementation

        }

    }

    catch (e) {} // defer to JS implementation

}

Y.mix(Y.namespace('JSON'),{ parse : _parse });

}, '3.0.0b1' );

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

/**

 * Provides Y.JSON.stringify method for converting objects to JSON strings.

 *

 * @module json

 * @submodule json-stringify

 * @for JSON

 * @static

 */

var _toString = Object.prototype.toString,

    Lang      = Y.Lang,

    isFunction= Lang.isFunction,

    isArray   = Lang.isArray,

    type      = Lang.type,

    STRING    = 'string',

    NUMBER    = 'number',

    BOOLEAN   = 'boolean',

    OBJECT    = 'object',

    ARRAY     = 'array',

    REGEXP    = 'regexp',

    ERROR     = 'error',

    NULL      = 'null',

    DATE      = 'date',

    EMPTY     = '',

    OPEN_O    = '{',

    CLOSE_O   = '}',

    OPEN_A    = '[',

    CLOSE_A   = ']',

    COMMA     = ',',

    COMMA_CR  = ",\n",

    CR        = "\n",

    COLON     = ':',

    COLON_SP  = ': ',

    QUOTE     = '"';

Y.mix(Y.namespace('JSON'),{

    /**

     * Regex used to capture characters that need escaping before enclosing

     * their containing string in quotes.

     *

     * @property _SPECIAL_CHARS

     * @type {RegExp}

     * @protected

     */

    _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

     * @protected

     */

    _CHARS : {

        '\b': '\\b',

        '\t': '\\t',

        '\n': '\\n',

        '\f': '\\f',

        '\r': '\\r',

        '"' : '\\"',

        '\\': '\\\\'

    },

    /**

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

     * stringify.  Override this method if you need Dates serialized in a

     * different format.

     *

     * @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 QUOTE + d.getUTCFullYear()   + '-' +

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

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

              _zeroPad(d.getUTCHours())     + COLON +

              _zeroPad(d.getUTCMinutes())   + COLON +

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

    },

    /**

     * <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>

     *

     * @method stringify

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

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

     *                  keys to include, or a replacer function to modify the

     *                  raw value before serialization

     * @param ind {Number|String} (optional) indentation character or depth of

     *                  spaces to format the output.

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

     * @static

     */

    stringify : function (o,w,ind) {

        var m      = Y.JSON._CHARS,

            str_re = Y.JSON._SPECIAL_CHARS,

            rep    = isFunction(w) ? w : null,

            pstack = [], // Processing stack used for cyclical ref protection

            _date  = Y.JSON.dateToString, // Use configured date serialization

            format = _toString.call(ind).match(/String|Number/);

        if (rep || typeof w !== 'object') {

            w = undefined;

        }

        if (format) {

            // String instances and primatives are left alone.  String objects

            // coerce for the indenting operations.

            if (format[0] === 'Number') {

                // force numeric indent values between {0,100} per the spec

                // This also converts Number instances to primative

                ind = new Array(Math.min(Math.max(0,ind),100)+1).join(" ");

            }

            // turn off formatting for 0 or empty string

            format = ind;

        }

        // escape encode special characters

        function _char(c) {

            if (!m[c]) {

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

            }

            return m[c];

        }

        // Enclose the escaped string in double quotes

        function _string(s) {

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

        }

        // Check for cyclical references

        function _cyclicalTest(o) {

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

                if (pstack[i] === o) {

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

                }

            }

            return false;

        }

        function _indent(s) {

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

        }

        function _object(o,arr) {

            // Add the object to the processing stack

            pstack.push(o);

            var a = [],

                colon = format ? COLON_SP : COLON,

                i, j, len, k, v;

            if (arr) { // Array