;
(function (win) {
    var store = {},
        doc = win.document,
        localStorageName = 'localStorage',
        scriptTag = 'script',
        storage;

    store.disabled = false;
    store.set = function (key, value) {
    };
    store.get = function (key) {
    };
    store.remove = function (key) {
    };
    store.clear = function () {
    };
    store.transact = function (key, defaultVal, transactionFn) {
        var val = store.get(key);
        if (transactionFn == null) {
            transactionFn = defaultVal;
            defaultVal = null
        }
        if (typeof val == 'undefined') {
            val = defaultVal || {}
        }
        transactionFn(val);
        store.set(key, val)
    };
    store.getAll = function () {
    };
    store.forEach = function () {
    };

    store.serialize = function (value) {
        return JSON.stringify(value)
    };
    store.deserialize = function (value) {
        if (typeof value != 'string') {
            return undefined
        }
        try {
            return JSON.parse(value)
        }
        catch (e) {
            return value || undefined
        }
    };

    // Functions to encapsulate questionable FireFox 3.6.13 behavior
    // when about.config::dom.storage.enabled === false
    // See https://github.com/marcuswestin/store.js/issues#issue/13
    function isLocalStorageNameSupported() {
        try {
            return (localStorageName in win && win[localStorageName])
        }
        catch (err) {
            return false
        }
    }

    if (isLocalStorageNameSupported()) {
        storage = win[localStorageName];
        store.set = function (key, val) {
            if (val === undefined) {
                return store.remove(key)
            }
            storage.setItem(key, store.serialize(val));
            return val
        };
        store.get = function (key) {
            return store.deserialize(storage.getItem(key))
        };
        store.remove = function (key) {
            storage.removeItem(key)
        };
        store.clear = function () {
            storage.clear()
        };
        store.getAll = function () {
            var ret = {};
            store.forEach(function (key, val) {
                ret[key] = val
            });
            return ret
        };
        store.forEach = function (callback) {
            for (var i = 0; i < storage.length; i++) {
                var key = storage.key(i);
                callback(key, store.get(key))
            }
        }
    } else if (doc.documentElement.addBehavior) {
        var storageOwner,
            storageContainer;
        // Since #userData storage applies only to specific paths, we need to
        // somehow link our data to a specific path.  We choose /favicon.ico
        // as a pretty safe option, since all browsers already make a request to
        // this URL anyway and being a 404 will not hurt us here.  We wrap an
        // iframe pointing to the favicon in an ActiveXObject(htmlfile) object
        // (see: http://msdn.microsoft.com/en-us/library/aa752574(v=VS.85).aspx)
        // since the iframe access rules appear to allow direct access and
        // manipulation of the document element, even for a 404 page.  This
        // document can be used instead of the current document (which would
        // have been limited to the current path) to perform #userData storage.
        try {
            storageContainer = new ActiveXObject('htmlfile');
            storageContainer.open();
            storageContainer.write('<' + scriptTag + '>document.w=window</' + scriptTag + '><iframe src="/favicon.ico"></iframe>');
            storageContainer.close();
            storageOwner = storageContainer.w.frames[0].document;
            storage = storageOwner.createElement('div')
        } catch (e) {
            // somehow ActiveXObject instantiation failed (perhaps some special
            // security settings or otherwse), fall back to per-path storage
            storage = doc.createElement('div');
            storageOwner = doc.body
        }

        function withIEStorage(storeFunction) {
            return function () {
                var args = Array.prototype.slice.call(arguments, 0);
                args.unshift(storage);
                // See http://msdn.microsoft.com/en-us/library/ms531081(v=VS.85).aspx
                // and http://msdn.microsoft.com/en-us/library/ms531424(v=VS.85).aspx
                storageOwner.appendChild(storage);
                storage.addBehavior('#default#userData');
                storage.load(localStorageName);
                var result = storeFunction.apply(store, args);
                storageOwner.removeChild(storage);
                return result
            }
        }

        // In IE7, keys cannot start with a digit or contain certain chars.
        // See https://github.com/marcuswestin/store.js/issues/40
        // See https://github.com/marcuswestin/store.js/issues/83
        var forbiddenCharsRegex = new RegExp("[!\"#$%&'()*+,/\\\\:;<=>?@[\\]^`{|}~]", "g");

        function ieKeyFix(key) {
            return key.replace(/^d/, '___$&').replace(forbiddenCharsRegex, '___')
        }

        store.set = withIEStorage(function (storage, key, val) {
            key = ieKeyFix(key);
            if (val === undefined) {
                return store.remove(key)
            }
            storage.setAttribute(key, store.serialize(val));
            storage.save(localStorageName);
            return val
        });
        store.get = withIEStorage(function (storage, key) {
            key = ieKeyFix(key);
            return store.deserialize(storage.getAttribute(key))
        });
        store.remove = withIEStorage(function (storage, key) {
            key = ieKeyFix(key);
            storage.removeAttribute(key);
            storage.save(localStorageName)
        });
        store.clear = withIEStorage(function (storage) {
            var attributes = storage.XMLDocument.documentElement.attributes;
            storage.load(localStorageName);
            for (var i = 0, attr; attr = attributes[i]; i++) {
                storage.removeAttribute(attr.name)
            }
            storage.save(localStorageName)
        });
        store.getAll = function (storage) {
            var ret = {};
            store.forEach(function (key, val) {
                ret[key] = val
            });
            return ret
        };
        store.forEach = withIEStorage(function (storage, callback) {
            var attributes = storage.XMLDocument.documentElement.attributes;
            for (var i = 0, attr; attr = attributes[i]; ++i) {
                callback(attr.name, store.deserialize(storage.getAttribute(attr.name)))
            }
        })
    }

    try {
        var testKey = '__storejs__';
        store.set(testKey, testKey);
        if (store.get(testKey) != testKey) {
            store.disabled = true
        }
        store.remove(testKey)
    } catch (e) {
        store.disabled = true
    }
    store.enabled = !store.disabled;

    if (typeof module != 'undefined' && module.exports && this.module !== module) {
        module.exports = store
    }
    else if (typeof define === 'function' && define.amd) {
        define(store)
    }
    else {
        win.store = store
    }

})(Function('return this')());
