localStorage ORM

asyncLs

(function(exports) {
    var mod = function (databaseName, saveInterval) {
        var self;

        saveInterval = saveInterval || 2000;
        databaseName = databaseName || 'unnamed';
  
        this.hasChanged = false;
        this.store = {};

        if (typeof exports.localStorage === 'object') {
            self = this;
            
            this.hasLocalStorage = true;
            databaseName = 'localStorageORM/' + databaseName;

            if (exports.localStorage.getItem(databaseName)) {
                this.store = JSON.parse(exports.localStorage.getItem(databaseName));
            }
            
            setInterval(function() {
                if (self.hasChanged) {
                    exports.localStorage.setItem(databaseName, JSON.stringify(self.store));
                    self.hasChanged = false;
                }
            }, saveInterval);
        }
    }

    mod.fn = mod.prototype;

    mod.fn.get = function (key) {
        return this.store[key];
    };

    mod.fn.set = function (key, data) {
        this.store[key] = data;
        this.hasChanged = true;
    };

    mod.fn.find = function (attribute, value) {
        var i, iMax, result;

        result = [];

        for (i = 0, iMax = this.store.length; i < iMax; i++) {
            if (this.store[i][attribute] && this.store[i][attribute] === value) {
                result.push(this.store[i]);
            }
        }

        return result;
    };

    mod.fn.each = function (callback) {
    	var key;

    	for (key in this.store) {
    		if (this.store.hasOwnProperty(key)) {
    			callback.bind(this, key, this.store[key]);
    		}
    	}
    };

    exports.localStorageORM = mod;

}(window));


/*******************
 Usage
 *******************/

// Initiate
var users = new localStorageORM("users" /* database name */, 1000 /* save interval in ms */);

// Set value to key
users.set("eva" /* key */, {hair: "brown", eyes: "green"} /* value */);

// Get value by key
eva = users.get("eva" /*key */);

// Get an array of documents by attribute.
brownHairedPeople = users.find("hair" /* attribute */, "brown" /* value */);

// For each document, call a function
users.each(function(key, data) {
	console.log(key, data);
});