(function(window) {
    var ARRAY = 'array',
        BOOLEAN = 'boolean',
        DATE = 'date',
        ERROR = 'error',
        FUNCTION = 'function',
        NUMBER = 'number',
        NULL = 'null',
        OBJECT = 'object',
        REGEX = 'regexp',
        STRING = 'string',
        UNDEFINED = 'undefined',
        TYPES = {
            'undefined': UNDEFINED,
            'number': NUMBER,
            'boolean': BOOLEAN,
            'string': STRING,
            '[object Number]': NUMBER,
            '[object Boolean]': BOOLEAN,
            '[object String]': STRING,
            '[object Function]': FUNCTION,
            '[object RegExp]': REGEX,
            '[object Array]': ARRAY,
            '[object Date]': DATE,
            '[object Object]': OBJECT,
            '[object Error]': ERROR
        },
        _toStr = Object.prototype.toString,
        _type = function(o) {
            return TYPES[typeof o] || TYPES[_toStr.call(o)] || (o ? OBJECT : NULL);
        },

        _isNull = function(o) {
            return _type(o) === NULL;
        },
        _isUndefined = function(o) {
            return _type(o) === UNDEFINED;
        },
        _isFunction = function(o) {
            return _type(o) === FUNCTION;
        },
        _isBoolean = function(o) {
            return _type(o) === BOOLEAN;
        },
        _isNumber = function(o) {
            return _type(o) === NUMBER;
        },
        _isString = function(o) {
            return _type(o) === STRING;
        },
        _isArray = Array.isArray || function(o) {
            return _type(o) === ARRAY;
        },
        _isObject = function(o) {
            return _type(o) === OBJECT;
        },

        MAP = Array.prototype.map,
        _map = MAP ?
            function(array, callback, context) {
                return MAP.call(array, callback, context);
            } :
            function(array, callback, context) {
                var ret = [], i = 0, len = array.length;
                if (_isFunction(callback)) {
                    for( ; i < len; i++) {
                        ret[i] = callback.call(context, array[i], i, array);
                    }
                    return ret;
                }
                return slice.call(array, 0);
            },

        stack = [],

        pieceParser = function(eq) {
            var _unescape = window.QueryString.unescape;

            return function parsePiece (key, val) {
                var sliced, numVal, head, tail, ret;
                if (arguments.length !== 2) {
                    // key=val, called from the map/reduce
                    key = key.split(eq);
                    return parsePiece(
                        _unescape(key.shift()),
                        _unescape(key.join(eq))
                    );
                }
                key = key.replace(/^\s+|\s+$/g, '');
                if (_isString(val)) {
                    val = val.replace(/^\s+|\s+$/g, '');
                    // convert numerals to numbers
                    if (!isNaN(val)) {
                        numVal = +val;
                        if (val === numVal.toString(10)) {
                            val = numVal;
                        }
                    }
                }
                sliced = /(.*)\[([^\]]*)\]$/.exec(key);
                if (!sliced) {
                    ret = {};
                    if (key) {
                        ret[key] = val;
                    }
                    return ret;
                }
                // ["foo[][bar][][baz]", "foo[][bar][]", "baz"]
                tail = sliced[2];
                head = sliced[1];

                // array: key[]=val
                if (!tail) {
                    return parsePiece(head, [val]);
                }

                // obj: key[subkey]=val
                ret = {};
                ret[tail] = val;
                return parsePiece(head, ret);
            };
        },

        // the reducer function that merges each query piece together into one set of params
        mergeParams = function(params, addition) {
            return (
                // if it's uncontested, then just return the addition.
                (!params) ? addition
                // if the existing value is an array, then concat it.
                : (_isArray(params)) ? params.concat(addition)
                // if the existing value is not an array, and either are not objects, arrayify it.
                : (!_isObject(params) || !_isObject(addition)) ? [params].concat(addition)
                // else merge them as objects, which is a little more complex
                : mergeObjects(params, addition)
            );
        },

        // Merge two *objects* together. If this is called, we've already ruled
        // out the simple cases, and need to do the for-in business.
        mergeObjects = function(params, addition) {
            for (var i in addition) {
                if (i && addition.hasOwnProperty(i)) {
                    params[i] = mergeParams(params[i], addition[i]);
                }
            }
            return params;
        },

        /**
         * 
         */
        _parse = function(qs) {
            var arr = qs.split('&'),
                arrMap = _map(arr, pieceParser('=')),
                result = {},
                i = 0, length = arrMap.length;

            for ( ; i < length; i++) {
                result = mergeParams(result, arrMap[i]);
            }

            return result;
        },

        _stringify = function(obj, arrayKey, name) {
            var begin, end, i, l, n, s,
                sep = '&', eq = '=',
                _escape = window.QueryString.escape;
            arrayKey = !!arrayKey;

            if (_isNull(obj) || _isUndefined(obj) || _isFunction(obj)) {
                return name ? _escape(name) + eq : '';
            }

            if (_isBoolean(obj) || _toStr.call(obj) === '[object Boolean]') {
                obj =+ obj;
            }

            if (_isNumber(obj) || _isString(obj)) {
                return _escape(name) + eq + _escape(obj);
            }

            if (_isArray(obj)) {
                s = [];
                name = arrayKey ? name + '[]' : name;
                l = obj.length;
                for (i = 0; i < l; i++) {
                    s.push( _stringify(obj[i], arrayKey, name) );
                }

                return s.join(sep);
            }

            // Check for cyclical references in nested objects
            for (i = stack.length - 1; i >= 0; --i) {
                if (stack[i] === obj) {
                    return '';
                }
            }

            stack.push(obj);
            s = [];
            begin = name ? name + '[' : '';
            end = name ? ']' : '';
            for (i in obj) {
                if (obj.hasOwnProperty(i)) {
                    n = begin + i + end;
                    s.push( _stringify(obj[i], arrayKey, n) );
                }
            }

            stack.pop();
            s = s.join(sep);
            if (!s && name) {
                return name + "=";
            }

            return s;
        };


    window.QueryString = {
        escape: encodeURIComponent,
        unescape: function(s) {
            return decodeURIComponent(s.replace(/\+/g, ' '));
        },
        stringify: _stringify,
        parse: _parse
    };
})(window);

/**
 * Cross-domain POST
 */
(function(window) {
    var supportPostMsg = !!window.postMessage,

        _extend = function (dest, src, overwrite) {
            if (!src || !dest || dest === src) {
                return dest || null;
            }
            var key;
            if (overwrite) { // 覆盖模式
                for (key in src) {
                    dest[key] = src[key];
                }
            } else { // 非覆盖模式
                for (key in src) {
                    if (!dest.hasOwnProperty(key)) {
                        dest[key] = src[key];
                    }
                }
            }
            return dest;
        },

        ARRAY = 'array',
        BOOLEAN = 'boolean',
        DATE = 'date',
        ERROR = 'error',
        FUNCTION = 'function',
        NUMBER = 'number',
        NULL = 'null',
        OBJECT = 'object',
        REGEX = 'regexp',
        STRING = 'string',
        UNDEFINED = 'undefined',
        TYPES = {
            'undefined': UNDEFINED,
            'number': NUMBER,
            'boolean': BOOLEAN,
            'string': STRING,
            '[object Number]': NUMBER,
            '[object Boolean]': BOOLEAN,
            '[object String]': STRING,
            '[object Function]': FUNCTION,
            '[object RegExp]': REGEX,
            '[object Array]': ARRAY,
            '[object Date]': DATE,
            '[object Object]': OBJECT,
            '[object Error]': ERROR
        },
        _toStr = Object.prototype.toString,
        _type = function(o) {
            return TYPES[typeof o] || TYPES[_toStr.call(o)] || (o ? OBJECT : NULL);
        },
        _isNull = function(o) {
            return _type(o) === NULL;
        },
        _isUndefined = function(o) {
            return _type(o) === UNDEFINED;
        },
        _isFunction = function(o) {
            return _type(o) === FUNCTION;
        },
        _isBoolean = function(o) {
            return _type(o) === BOOLEAN;
        },
        _isNumber = function(o) {
            return _type(o) === NUMBER;
        },
        _isString = function(o) {
            return _type(o) === STRING;
        },
        _isArray = Array.isArray || function(o) {
            return _type(o) === ARRAY;
        },
        _isObject = function(o) {
            return _type(o) === OBJECT;
        },

        _arrayify = (function() {
            var SLICE = Array.prototype.slice,
                sliceIt = function(arr) {
                    return SLICE.call(arr, 0);
                };

            try {
                SLICE.call(document.documentElement.childNodes, 0);
            } catch(e) {
                sliceIt = function(arr) {
                    // IE 下对 NodeList、HTMLCollection 等 slice 会抛异常
                    var result = [], length = arr.length, i = 0;
                    for ( ; i < length; i++) {
                        result[i] = arr[i];
                    }
                    return result;
                };
            }
            return function(obj) {
                if (obj === undefined) return [];

                if (_isArray(obj)) return obj;

                if (obj === null || typeof obj.length !== 'number'
                    || _isString(obj) || _isFunction(obj)) {
                    return [obj];
                }

                return sliceIt(obj);
            };
        })(),

        _spTrim = String.prototype.trim,
        _trim = _spTrim ?
            function(s) {
                return (!s) ? '' : _spTrim.call(s);
            } :
            function(s) {
                return (!s) ? '' : s.toString().replace(/^\s+|\s+$/g, '');
            },

        _id = function(prefix) {
            prefix = prefix || '';
            var rnd = (Math.random() + '').slice(2),
                date = (new Date()).getTime();
            return '' + prefix + date + rnd;
        },

        document = window.document,
        _cloneNode = function(node) {
            var newNode = node.cloneNode(true);
            // MSIE 6/7 bug related to some form field elements
            if (ie < 8) {
                newNode.innerHTML = node.innerHTML;
            }
            return newNode;
        },
        _divCreator = function(str, doc) {
            var frag = doc.createElement('div');
            frag.innerHTML = str;
            return frag;
        },
        _createFragment = function(nodes, doc) {
            if (nodes && nodes.length) {
                var frag = null, i = 0, length = nodes.length;

                doc = doc || nodes[0].ownerDocument;
                frag = doc.createDocumentFragment();

                if (nodes.item) { // a live NodeList
                    nodes = _arrayify(nodes);
                }

                for (i = 0, len = nodes.length; i < len; i++) {
                    frag.appendChild(nodes[i]); 
                }
                return frag;
            }
            return null;
        },
        _createFromStr = function(str, doc) {
            if (typeof str === 'string' && (str = _trim(str))) {
                var nodes = null, created, creator = _divCreator;
                doc = doc || document;

                created = creator(str, doc).childNodes;
                if (created.length === 1) {
                    nodes = created[0].parentNode.removeChild(created[0]);
                } else {
                    nodes = _createFragment(created, doc);
                }
                return nodes;
            }
            return null;
        },

        _defUrl = 'http://api.sina.com.cn/script/javascript/postmsg.html',
        _defDomain = 'sina.com.cn',

        XDPost = {
            extend: _extend,
            arrayify: _arrayify,
            trim: _trim,
            later: function(options) {
                var timerId, f, delayFunc, fn, delay, isPeriodic, params, context,
                    defaults = {
                        fn: function() {},
                        delay: 0,
                        isPeriodic: false,
                        context: null,
                        params: []
                    };

                if (!_isFunction(options) && _isObject(options)) {
                    _extend(options, defaults, false);
                    fn = options.fn;
                    delay = options.delay || 0;
                    isPeriodic = !!options.isPeriodic;
                    params = options.params;
                    context = options.context;
                }
                else {
                    fn = arguments[0];
                    delay = arguments[1] || 0;
                    isPeriodic = !!arguments[2];
                    context = arguments[3] || null;
                    params = arguments[4] || [];
                }


                f = fn;
                if (context && typeof fn === 'string') {
                    f = context[fn];
                }

                if (!f) return null;

                delayFunc = (params && params.length) ? // (typeof params !== 'undefined') ?
                    function() {
                        f.apply(context, params);
                    } :
                    function() {
                        f.call(context);
                    };

                timerId = isPeriodic ? setInterval(delayFunc, delay) : setTimeout(delayFunc, delay);

                // 返回定时器对象
                return {
                    id: timerId,
                    periodic: isPeriodic,
                    cancel: function() {
                        if (this.periodic) {
                            clearInterval(this.id);
                        }
                        else {
                            clearTimeout(this.id);
                        }
                    }
                };
            },
            type: _type,
            isNull: _isNull,
            isUndefined: _isUndefined,
            isFunction: _isFunction,
            isBoolean: _isBoolean,
            isNumber: _isNumber,
            isString: _isString,
            isArray: _isArray,
            isObject: _isObject,
            createNode: _createFromStr,
            cloneNode: _cloneNode,
            generateId: _id,

            mode: supportPostMsg ? 'html5' : 'iframe',
            config: {
                proxyUrl: _defUrl,
                domain: _defDomain,
                form: null
            },
            setConfig: function(cfg) {
                _extend(XDPost.config, cfg, true);
            },

            send: supportPostMsg ?
                function(cfg) {
                    var sender = XDPost.sender, config = XDPost.config;
                    if (!sender) {
                        sender = new XDPost.Html5MsgSender({
                            proxyUrl: config.proxyUrl
                        });
                        this.sender = sender;
                    }
                    sender.send(cfg);
                    return sender;
                } :
                function(cfg) {
                    var sender, config = XDPost.config;
                    sender = new XDPost.IframeMsgSender({
                        domain: config.domain,
                        form: config.form
                    });
                    sender.send(cfg);
                    return sender;
                }
        };

    window.XDPost = XDPost;
})(window);

/**
 * Cross-domain POST using window.postMessage()
 */
(function(window) {
    var XDPost = window.XDPost,
        _extend = XDPost.extend,
        _isFunction = XDPost.isFunction,
        _later = XDPost.later,

        _add = document.addEventListener ?
            function(elem, type, fn) {
                if (elem && elem.addEventListener) {
                    elem.addEventListener(type, fn, false);
                }
            } :
            function(elem, type, fn) {
                if (elem && elem.attachEvent) {
                    elem.attachEvent('on' + type, fn);
                }
            },
        _remove = document.removeEventListener ?
            function(elem, type, fn) {
                if (elem && elem.removeEventListener) {
                    elem.removeEventListener(type, fn, false);
                }
            } :
            function(elem, type, fn) {
                if (elem && elem.detachEvent) {
                    elem.detachEvent('on' + type, fn);
                }
            },

        NOOP = function() {},
        RE_URL = /^http\s?\:\/\/[a-z\d\-\.]+/i,
        ID_PREFIX = 'sina-xdpost-iframe-',
        _id = XDPost.generateId,

        /**
         * Message sender class
         */
        MsgSender = function(cfg) {
            if (!(this instanceof MsgSender)) {
                return new MsgSender(cfg);
            }
            cfg = cfg || {};
            this.init(cfg);
        };

    _extend(MsgSender.prototype, {
        ready: false,

        init: function(cfg) {
            if (this.ready) {
                return;
            }
            var me = this,
                iframeId, iframeHtml, iframe, loaded, receiver,
                proxyUrl = cfg.proxyUrl;
            me.onsuccess = cfg.onsuccess || NOOP;
            me.onfailure = cfg.onfailure || NOOP;
            if (!proxyUrl) {
                return;
            }

            receiver = function(e) {
                if (!me.ready || e.origin !== me.target) {
                    return;
                }
                var ret = e.data;
                if (!ret || ret === 'failure') {
                    me.onfailure && me.onfailure();
                } else {
                    me.onsuccess && me.onsuccess(e.data);
                }
            };
            _add(window, 'message', receiver);

            // insert an iframe
            iframeId = _id(ID_PREFIX);
            iframeHtml = '<iframe id="' + iframeId + '" name="' + iframeId + 
                '" src="' + proxyUrl + '" frameborder="0" ' +
                'style="width:0;height:0;display:none;"></iframe>';
            iframe = XDPost.createNode(iframeHtml);
            loaded = function() {
                me.ready = true;
                var src = iframe.src,
                    matched = src.match(RE_URL);
                me.target = (matched && matched[0]) || '*';
            };
            _add(iframe, 'load', loaded);
            document.body.insertBefore(iframe, document.body.firstChild);

            me._iframe = iframe;
            me._iframeLoaded = loaded;
            me._receiver = receiver;
        },

        send: function(cfg) {
            cfg = cfg || {};
            var me = this,
                url = cfg.url,
                data = cfg.data,
                onsuccess = cfg.onsuccess,
                onfailure = cfg.onfailure;

            if (!url || typeof url !== 'string') {
                return;
            }
            if (onsuccess) {
                me.onsuccess = onsuccess;
            }
            if (onfailure) {
                me.onfailure = onfailure;
            }

            if (!me.ready) {
                _later(function() {
                    me.send(cfg);
                }, 50);
                return;
            }

            if (data) {
                data += '&_url=' + window.encodeURIComponent(url);
            } else {
                data = '_url=' + window.encodeURIComponent(url);
            }
            me._iframe.contentWindow.postMessage(data, me.target);
        },

        destroy: function() {
            var iframe = this._iframe;
            _remove(iframe, 'load', this._iframeLoaded);
            iframe.parentNode.removeChild(iframe);
            _remove(window, 'message', this._receiver);
            this._iframe = null;
            this._iframeLoaded = null;
            this._receiver = null;
        }
    });

    XDPost.Html5MsgSender = MsgSender;
})(window);

/**
 * Cross-domain POST using iframe
 */
(function(window) {
    var XDPost = window.XDPost,
        _extend = XDPost.extend,
        // _ready = XDPost.ready,
        _later = XDPost.later,
        QS = window.QueryString,
        _parse = QS.parse,

        NOOP = function() {},
        FORM_PREFIX = 'sina-xdpost-form-',
        IFRAME_PREFIX = 'sina-xdpost-iframe-',
        _id = XDPost.generateId,

        /**
         * Message sender class
         */
        MsgSender = function(cfg) {
            if (!(this instanceof MsgSender)) {
                return new MsgSender(cfg);
            }
            cfg = cfg || {};
            this.init(cfg);
        };

    MsgSender.defaultDomain = 'sina.com.cn';
    _extend(MsgSender.prototype, {
        ready: false,

        init: function(cfg) {
            if (this.ready) {
                return;
            }
            var me = this,
                formId, placeholder, fnName, callback,
                form = cfg.form,
                domain = cfg.domain || MsgSender.defaultDomain;
            me.onsuccess = cfg.onsuccess || NOOP;
            me.onfailure = cfg.onfailure || NOOP;

            if (!form) {
                // create a hidden form
                formId = _id(FORM_PREFIX);
                form = document.createElement('form');
                form.id = formId;
                form.method = 'POST';
                document.body.insertBefore(form, document.body.firstChild);
                // me.ready = true;
            }

            callback = function(data) {
                me._clear();
                me.onsuccess && me.onsuccess(data);
            };
            fnName = _id('callback');
            window[fnName] = callback;

            // me.ready = S.isReady;
            me.ready = true;
            me._callbackName = fnName;
            me._form = form;
            document.domain = domain;
        },

        send: function(cfg) {
            cfg = cfg || {};
            var me = this, db,
                iframeId, iframeHtml, iframe, placeholder,
                form, key, inputs = [],
                fnName = me._callbackName,
                url = cfg.url,
                data = cfg.data,
                onsuccess = cfg.onsuccess,
                onfailure = cfg.onfailure;

            if (!url || typeof url !== 'string') {
                return;
            }
            if (onsuccess) {
                me.onsuccess = onsuccess;
            }
            if (onfailure) {
                me.onfailure = onfailure;
            }

            if (!me.ready) {
                _later(function() {
                    me.send(cfg);
                }, 50);
                return;
            }

            if (!(placeholder = me._placeholder)) {
                db = document.body;
                placeholder = document.createElement('div');
                placeholder.style.display = 'none';
                placeholder.style.visibility = 'hidden';
                // document.body.appendChild(placeholder);
                db.insertBefore(placeholder, db.firstChild);
                me._placeholder = placeholder;
            }
            form = this._form;
            iframeId = _id(IFRAME_PREFIX);
            iframeHtml = '<iframe id="' + iframeId + '" name="' + iframeId + 
                '" src="about:blank" frameborder="0" ' +
                'style="width:0;height:0;display:none;"></iframe>';
            this._iframeId = iframeId;
            placeholder.innerHTML = iframeHtml;
            if (url.indexOf('?') === -1) {
                form.action = url + '?callback=' + fnName;
            } else {
                form.action = url + '&callback=' + fnName;
            }
            form.target = iframeId;

            if (data) {
                if (typeof data === 'string') {
                    data = _parse(data) || {};
                }
                for (key in data) {
                    inputs.push('<input type="hidden" name="');
                    inputs.push(key);
                    inputs.push('" value="');
                    inputs.push(data[key]);
                    inputs.push('" />');
                }
                frag = XDPost.createNode(inputs.join(''));
                form.appendChild(frag);
            }

            form.submit();
            form.removeChild(frag);
        },

        inProgress: function() {
            return !!(me._iframeId && document.getElementById(me._iframeId));
        },

        _clear: function() {
            var iframe = this._iframeId &&
                document.getElementById(this._iframeId);
            if (iframe) {
                iframe.parentNode.removeChild(iframe);
            }
            this._iframeId = null;
        },

        cancel: function() {
            this._clear();
        },

        destroy: function() {
            var form = this._form, ph = this._placeholder;
            form.parentNode.removeChild(form);
            ph.parentNode.removeChild(ph);
            this._form = null;
            this._placeholder = null;
            delete window[this._callbackName];
            this._iframeId = null;
        }
    });

    XDPost.IframeMsgSender = MsgSender;
})(window);

/**
 * JSON 字符串与 JavaScript 数据的相互转换.
 * @module json
 * @author 朴扬
 */
(function(window) {
    var _toStr = Object.prototype.toString,
        isFunction = function(o) {
            return (_toStr.call(o) === '[object Function]');
        },
        isObject = function(o) {
            return (_toStr.call(o) === '[object Object]');
        },
        isArray = function(o) {
            return (_toStr.call(o) === '[object Array]');
        },
        gJSON = window.JSON,
        Native = (_toStr.call(gJSON) === '[object JSON]' && gJSON),
        useNativeStringify = !!Native,
        useNativeParse = useNativeStringify,

        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     = '"',

        // Regex used to capture characters that need escaping before enclosing
        // their containing string in quotes.
        _SPECIAL_CHARS = /[\\\"\x00-\x1f\x7f-\x9f\u00ad\u0600-\u0604\u070f\u17b4\u17b5\u200c-\u200f\u2028-\u202f\u2060-\u206f\ufeff\ufff0-\uffff]/g,

        _CHARS = {
            '\b': '\\b',
            '\t': '\\t',
            '\n': '\\n',
            '\f': '\\f',
            '\r': '\\r',
            '"' : '\\"',
            '\\': '\\\\'
        },

// =============================== stringify ===============================

        // Utility function used to determine how to serialize a variable.
        _type = function(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
        },

        // Escapes a special character to a safe Unicode representation
        _char = function(c) {
            if (!_CHARS[c]) {
                _CHARS[c] =  '\\u' + ('0000' + (+(c.charCodeAt(0))).toString(16)).slice(-4);
            }
            return _CHARS[c];
        },

        // Enclose escaped strings in quotes
        _string = function(s) {
            return QUOTE + s.replace(_SPECIAL_CHARS, _char) + QUOTE;
        },

        // Adds the provided space to the beginning of every line in the input string
        _indent = function(s, space) {
            return s.replace(/^/gm, space);
        },

        // JavaScript implementation of stringify (see API declaration of stringify)
        _stringify = function(o, w, space) {
            if (o === undefined) {
                return undefined;
            }

            var replacer = isFunction(w) ? w : null,
                format   = _toStr.call(space).match(/String|Number/) || [],
                _date    = window.JSONUtils.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 (keys.hasOwnProperty(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}, '');
        }, 

        // =============================== parse ===============================

        _eval  = window['eval'],
        _UNICODE_EXCEPTIONS = /[\u0000\u00ad\u0600-\u0604\u070f\u17b4\u17b5\u200c-\u200f\u2028-\u202f\u2060-\u206f\ufeff\ufff0-\uffff]/g,
        _ESCAPES = /\\(?:["\\\/bfnrt]|u[0-9a-fA-F]{4})/g,
        _VALUES  = /"[^"\\\n\r]*"|true|false|null|-?\d+(?:\.\d*)?(?:[eE][+\-]?\d+)?/g,
        _BRACKETS = /(?:^|:|,)(?:\s*\[)+/g,
        _UNSAFE = /[^\],:{}\s]/,

        _escapeException = function (c) {
            return '\\u'+('0000'+(+(c.charCodeAt(0))).toString(16)).slice(-4);
        },

        _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 = function (s, reviver) {
            // 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 (!_UNSAFE.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');
        },

        _parseUsed;


    // Double check basic native functionality.  This is primarily to catch broken
    // early JSON API implementations in Firefox 3.1 beta1 and beta2.
    if (Native) {
        try {
            useNativeStringify = ('0' === Native.stringify(0));
        }
        catch (e) {
            useNativeStringify = false;
        }

        try {
            useNativeParse = (Native.parse('{"ok":false}', function(k, v) {
                return k === "ok" ? true : v;
            })).ok;
        }
        catch (e) {
            useNativeParse = false;
        }
    }

    _parseUsed = useNativeParse ? Native.parse : _parse;



    // expose
    window.JSONUtils = {
        /**
         * 序列化.
         */
        stringify: useNativeStringify ?  Native.stringify : _stringify,

        /**
         * 反序列化.
         */
        parse: function(s, reviver) {
            if (typeof s !== 'string') {
                s += '';
            }
            try {
                return _parseUsed(s, reviver);
            }
            catch (e) {
            }
        },
        
        // 测试用
        _stringify: _stringify,
        _parse: _parse,

        useNativeParse: useNativeParse,
        useNativeStringify: useNativeStringify
    };
})(window);
(function(window) {
    if (!window.WeiboFollow) {
        window.WeiboFollow = {};
    }

    var XDPost = window.XDPost,
        _extend = XDPost.extend,
        _isFunction = XDPost.isFunction,
        _isString = XDPost.isString,
        _isArray = XDPost.isArray,
        QS = window.QueryString,
        JSON = window.JSONUtils,
        NOOP = function() {},
        _isIE = !!window.ActiveXObject,

        _splitUrl = function(url) {
            var base, pSlash, pQs, pHash, qs, fragId;

            if ((pSlash = url.lastIndexOf('/')) === -1) {
                pSlash = 0;
            }
            pHash = url.indexOf('#', pSlash);
            fragId = (pHash > -1) ? url.substr(pHash + 1) : '';
            pQs = url.indexOf('?', pSlash);
            if (pQs > -1) {
                qs = (pHash > -1) ?
                    url.substr(pQs + 1, pHash - pQs - 1) : 
                    url.substr(pQs + 1);
                base = url.substr(0, pQs);
            } else {
                qs = '';
                base = (pHash > -1) ? url.substr(0, pHash) : url;
            }

            return [base, qs, fragId];
        },

        _scriptOnload = document.createElement('script').readyState ?
            function(node, callback) {
                var oldCallback = node.onreadystatechange;
                node.onreadystatechange = function() {
                    var rs = node.readyState;
                    if (rs === 'loaded' || rs === 'complete') {
                        node.onreadystatechange = null;
                        oldCallback && oldCallback();
                        callback.call(this);
                    }
                };
            } :
            function(node, callback) {
                node.addEventListener('load', callback, false);
            },
        _head = document.getElementsByTagName('head')[0] ||
            document.documentElement,
        _getScript = function(url, fn) {
            var node = document.createElement('script');
            node.src = url;
            node.async = true;
            _scriptOnload(node, function() {
                if (_isFunction(fn)) {
                    fn.call(node, '');
                }
                if (_head && node.parentNode) {
                    _head.removeChild(node);
                }
            });
            _head.insertBefore(node, _head.firstChild);
            return node;
        },
        _jsonp = function(url, data, success) {
            var jsonpCallback = arguments[3], jsonp = arguments[4];
            if (_isFunction(data)) {
                // 没有传 data 参数
                jsonp = jsonpCallback;
                jsonpCallback = success;
                success = data;
                data = null;
            }

            var splitted = _splitUrl(url),
                base = splitted[0], qs = splitted[1], fragId = splitted[2],
                rndCallback, str, tempCallback, fn = null;
            // data
            if (_isString(data)) {
                qs += (qs.length) ? '&' + data : data;
            }
            jsonp = jsonp || 'callback';
            rndCallback = 'jsonp' + (new Date()).getTime() +
                Math.floor(Math.random() * 100000);
            jsonpCallback = jsonpCallback || rndCallback;
            str = jsonp + '=' + jsonpCallback;
            qs += (qs.length) ? '&' + str : str;

            tempCallback = window[jsonpCallback];
            window[jsonpCallback] = function(data) {
                if (_isFunction(tempCallback)) {
                    tempCallback(data);
                } else {
                    try {
                        delete window[jsonpCallback];
                    } catch(e) {}
                    window[jsonpCallback] = undefined;
                }
                // onsuccess
                if (_isFunction(success)) {
                    success(data);
                }
            };

            // url = base + '?' + qs + '#' + fragId;
            url = base;
            if (qs) {
                url += '?' + qs;
            }
            if (fragId) {
                url += '#' + fragId;
            }
            return _getScript(url, fn);
        },

        _postRequest = function(opts) {
            opts = opts || {};
            var url = opts.url,
                data = opts.data || {},
                success = opts.onsuccess || NOOP,
                failure = opts.onfailure || NOOP,
                onsuccess;
                // failure = function() {
                //     onfailure({'code': -10000002, 'msg': '通讯错误'});
                // };

            if (!url || typeof url !== 'string') {
                failure({code: -10000003, msg: '接口 URL 未指定'});
                return;
            }
            if (XDPost.mode === 'html5') {
                data = QS.stringify(data);
                onsuccess = function(ret) {
                    ret = JSON.parse(ret);
                    var status = ret && ret.result && ret.result.status;
                    if (status && status.code === 0) {
                        success(ret.result.data);
                    } else {
                        if (status) {
                            failure(status);
                        } else {
                            failure({code: -10000001, msg: '未知错误'});
                        }
                    }
                };
            } else {
                onsuccess = function(ret) {
                    var status = ret && ret.result && ret.result.status;
                    if (status && status.code === 0) {
                        success(ret.result.data);
                    } else {
                        if (status) {
                            failure(status);
                        } else {
                            failure({code: -10000001, msg: '未知错误'});
                        }
                    }
                };
            }
            XDPost.send({
                url: url,
                data: data,
                onsuccess: onsuccess,
                onfailure: NOOP
            });
        },

        _getRequest = function(opts) {
            opts = opts || {};
            var url = opts.url,
                data = opts.data || {},
                success = opts.onsuccess || NOOP,
                failure = opts.onfailure || NOOP;

            if (!url || typeof url !== 'string') {
                failure({code: -10000003, msg: '接口 URL 未指定'});
                return;
            }
            _jsonp(url, QS.stringify(data), function(ret) {
                var status = ret && ret.result && ret.result.status;
                if (status && status.code === 0) {
                    success(ret.result.data);
                } else {
                    if (status) {
                        failure(status);
                    } else {
                        failure({'code': -10000001, 'msg': '未知错误'});
                    }
                }
            });
        },

        SSO = 'sinaSSOManager',
        SSO_ERR = '未载入 SSO 模块',
        _apiBase = 'http://api.sina.com.cn/weibo/';


    _extend(WeiboFollow, {
        apis: {
            check: _apiBase + 'wb/friendships_exists.json',
            follow: _apiBase + 'wb/friendships_create.' +
                (_isIE ? 'xml' : 'json'),
            appKey: '2835469272'
        },
        config: function(cfg) {
            _extend(this.apis, cfg, true);
        },

        _check: function(opts) {
            opts = opts || {};
            var url = opts.url, apis = this.apis;
            if (!url) {
                url = apis.check;
            }
            if (url.indexOf('?') >= 0) {
                url += '&source=' + apis.appKey;
            } else {
                url += '?source=' + apis.appKey;
            }
            opts.url = url;
            _getRequest(opts);
        },

        _follow: function(opts) {
            opts = opts || {};
            var url = opts.url, apis = this.apis;
            if (!url) {
                url = apis.follow;
            }
            if (url.indexOf('?') >= 0) {
                url += '&source=' + apis.appKey;
            } else {
                url += '?source=' + apis.appKey;
            }
            opts.url = url;
            _postRequest(opts);
        },

        LOGIN_URL: 'http://weibo.com/login.php',
        LOGIN_MSG: '您还没有登录，无法添加关注。您是否现在登录？',

        check: function(users) {
            var sso = window[SSO], cookie, uid;
            cookie = sso && sso.getSinaCookie();
            uid = (cookie && cookie.uid) || 0;
            if (!_isArray(users)) {
                users = [users];
            }
            WeiboFollow._check({
                data: {
                    uid: uid,
                    uids: users.join(',')
                },
                onsuccess: function(data) {
                    WeiboFollow.oncheck && WeiboFollow.oncheck(data);
                },
                onfailure: function(status) {
                    alert('获取关注状态失败：' + status.msg);
                }
            });
        },

        follow: function(users,o) {
            var sso = window[SSO], cookie, uid;
            if (!sso) {
                alert(SSO_ERR);
                return;
            }
            cookie = sso.getSinaCookie();
            if (!cookie) {
                if (confirm(WeiboFollow.LOGIN_MSG) === true) {
                    window.open(WeiboFollow.LOGIN_URL);
                }
                return;
            }
            uid = (cookie && cookie.uid) || 0;
            if (!_isArray(users)) {
                users = [users];
            }
            WeiboFollow._follow({
                data: {
                    uid: uid,
                    uids: users.join(',')
                },
                onsuccess: function(data) {
                    alert('关注成功');
                    WeiboFollow.onfollow && WeiboFollow.onfollow(data,o);
                },
                onfailure: function(status) {
                    alert('关注失败：' + status.msg);
                }
            });
        },

        onfollow: function(data,o){
			o.parentNode.innerHTML = "<span class='add_yet'>已关注</span>";
			},
        oncheck: null
    });
})(window);