/*! store2 - v2.1.6 - 2014-03-10
 * Copyright (c) 2014 Nathan Bubna; Licensed MIT, GPL */
;(function(window, define) {
    var _ = {
        version: "2.1.6",
        areas: {},
        apis: {},

        // utilities
        inherit: function(api, o) {
            for (var p in api) {
                if (!o.hasOwnProperty(p)) {
                    o[p] = api[p];
                }
            }
            return o;
        },
        stringify: function(d) {
            return d === undefined || typeof d === "function" ? d+'' : JSON.stringify(d);
        },
        parse: function(s) {
            // if it doesn't parse, return as is
            try{ return JSON.parse(s); }catch(e){ return s; }
        },

        // extension hooks
        fn: function(name, fn) {
            _.storeAPI[name] = fn;
            for (var api in _.apis) {
                _.apis[api][name] = fn;
            }
        },
        get: function(area, key){ return area.getItem(key); },
        set: function(area, key, string){ area.setItem(key, string); },
        remove: function(area, key){ area.removeItem(key); },
        key: function(area, i){ return area.key(i); },
        length: function(area){ return area.length; },
        clear: function(area){ area.clear(); },

        // core functions
        Store: function(id, area, namespace) {
            var store = _.inherit(_.storeAPI, function(key, data, overwrite) {
                if (arguments.length === 0){ return store.getAll(); }
                if (data !== undefined){ return store.set(key, data, overwrite); }
                if (typeof key === "string"){ return store.get(key); }
                if (!key){ return store.clear(); }
                return store.setAll(key, data);// overwrite=data, data=key
            });
            store._id = id;
            store._area = area || _.inherit(_.storageAPI, { items: {}, name: 'fake' });
            store._ns = namespace || '';
            if (!_.areas[id]) {
                _.areas[id] = store._area;
            }
            if (!_.apis[store._ns+store._id]) {
                _.apis[store._ns+store._id] = store;
            }
            return store;
        },
        storeAPI: {
            // admin functions
            area: function(id, area) {
                var store = this[id];
                if (!store || !store.area) {
                    store = _.Store(id, area, this._ns);//new area-specific api in this namespace
                    if (!this[id]){ this[id] = store; }
                }
                return store;
            },
            namespace: function(namespace, noSession) {
                if (!namespace){
                    return this._ns ? this._ns.substring(0,this._ns.length-1) : '';
                }
                var ns = namespace, store = this[ns];
                if (!store || !store.namespace) {
                    store = _.Store(this._id, this._area, this._ns+ns+'.');//new namespaced api
                    if (!this[ns]){ this[ns] = store; }
                    if (!noSession){ store.area('session', _.areas.session); }
                }
                return store;
            },
            isFake: function(){ return this._area.name === 'fake'; },
            toString: function() {
                return 'store'+(this._ns?'.'+this.namespace():'')+'['+this._id+']';
            },

            // storage functions
            has: function(key) {
                if (this._area.has) {
                    return this._area.has(this._in(key));//extension hook
                }
                return !!(this._in(key) in this._area);
            },
            size: function(){ return this.keys().length; },
            each: function(fn, and) {
                for (var i=0, m=_.length(this._area); i<m; i++) {
                    var key = this._out(_.key(this._area, i));
                    if (key !== undefined) {
                        if (fn.call(this, key, and || this.get(key)) === false) {
                            break;
                        }
                    }
                    if (m > _.length(this._area)) { m--; i--; }// in case of removeItem
                }
                return and || this;
            },
            keys: function() {
                return this.each(function(k, list){ list.push(k); }, []);
            },
            get: function(key, alt) {
                var s = _.get(this._area, this._in(key));
                return s !== null ? _.parse(s) : alt || s;// support alt for easy default mgmt
            },
            getAll: function() {
                return this.each(function(k, all){ all[k] = this.get(k); }, {});
            },
            set: function(key, data, overwrite) {
                var d = this.get(key);
                if (d != null && overwrite === false) {
                    return data;
                }
                return _.set(this._area, this._in(key), _.stringify(data), overwrite) || d;
            },
            setAll: function(data, overwrite) {
                var changed, val;
                for (var key in data) {
                    val = data[key];
                    if (this.set(key, val, overwrite) !== val) {
                        changed = true;
                    }
                }
                return changed;
            },
            remove: function(key) {
                var d = this.get(key);
                _.remove(this._area, this._in(key));
                return d;
            },
            clear: function() {
                if (!this._ns) {
                    _.clear(this._area);
                } else {
                    this.each(function(k){ _.remove(this._area, this._in(k)); }, 1);
                }
                return this;
            },
            clearAll: function() {
                var area = this._area;
                for (var id in _.areas) {
                    if (_.areas.hasOwnProperty(id)) {
                        this._area = _.areas[id];
                        this.clear();
                    }
                }
                this._area = area;
                return this;
            },

            // internal use functions
            _in: function(k) {
                if (typeof k !== "string"){ k = _.stringify(k); }
                return this._ns ? this._ns + k : k;
            },
            _out: function(k) {
                return this._ns ?
                    k && k.indexOf(this._ns) === 0 ?
                        k.substring(this._ns.length) :
                        undefined : // so each() knows to skip it
                    k;
            }
        },// end _.storeAPI
        storageAPI: {
            length: 0,
            has: function(k){ return this.items.hasOwnProperty(k); },
            key: function(i) {
                var c = 0;
                for (var k in this.items){
                    if (this.has(k) && i === c++) {
                        return k;
                    }
                }
            },
            setItem: function(k, v) {
                if (!this.has(k)) {
                    this.length++;
                }
                this.items[k] = v;
            },
            removeItem: function(k) {
                if (this.has(k)) {
                    delete this.items[k];
                    this.length--;
                }
            },
            getItem: function(k){ return this.has(k) ? this.items[k] : null; },
            clear: function(){ for (var k in this.list){ this.removeItem(k); } },
            toString: function(){ return this.length+' items in '+this.name+'Storage'; }
        }// end _.storageAPI
    };

    // setup the primary store fn
    if (window.store){ _.conflict = window.store; }
    var store =
        // safely set this up (throws error in IE10/32bit mode for local files)
        _.Store("local", (function(){try{ return localStorage; }catch(e){}})());
    store.local = store;// for completeness
    store._ = _;// for extenders and debuggers...
    // safely setup store.session (throws exception in FF for file:/// urls)
    store.area("session", (function(){try{ return sessionStorage; }catch(e){}})());

    if (typeof define === 'function' && define.amd !== undefined) {
        define(function () {
            return store;
        });
    } else if (typeof module !== 'undefined' && module.exports) {
        module.exports = store;
    } else {
        window.store = store;
    }

})(window, window.define);
