Websites/browserbench.org/Speedometer/resources/todomvc/vanilla-examples/vanillajs/js/store.js

/*jshint eqeqeq:false */
(function (window) {
    'use strict';

    var localStorage = {}; // Benchmark modification: Avoid disk access.

    /**
     * Creates a new client side storage object and will create an empty
     * collection if no collection already exists.
     *
     * @param {string} name The name of our DB we want to use
     * @param {function} callback Our fake DB uses callbacks because in
     * real life you probably would be making AJAX calls
     */
    function Store(name, callback) {
    var data;
    var dbName;

    callback = callback || function () {};

    dbName = this._dbName = name;

    if (!localStorage[dbName]) {
    data = {
    todos: []
    };

    localStorage[dbName] = JSON.stringify(data);
    }

    callback.call(this, JSON.parse(localStorage[dbName]));
    }

    /**
     * Finds items based on a query given as a JS object
     *
     * @param {object} query The query to match against (i.e. {foo: 'bar'})
     * @param {function} callback     The callback to fire when the query has
     * completed running
     *
     * @example
     * db.find({foo: 'bar', hello: 'world'}, function (data) {
     *     // data will return any items that have foo: bar and
     *     // hello: world in their properties
     * });
     */
    Store.prototype.find = function (query, callback) {
    if (!callback) {
    return;
    }

    var todos = JSON.parse(localStorage[this._dbName]).todos;

    callback.call(this, todos.filter(function (todo) {
    for (var q in query) {
    return query[q] === todo[q];
    }
    }));
    };

    /**
     * Will retrieve all data from the collection
     *
     * @param {function} callback The callback to fire upon retrieving data
     */
    Store.prototype.findAll = function (callback) {
    callback = callback || function () {};
    callback.call(this, JSON.parse(localStorage[this._dbName]).todos);
    };

    /**
     * Will save the given data to the DB. If no item exists it will create a new
     * item, otherwise it'll simply update an existing item's properties
     *
     * @param {number} id An optional param to enter an ID of an item to update
     * @param {object} data The data to save back into the DB
     * @param {function} callback The callback to fire after saving
     */
    Store.prototype.save = function (id, updateData, callback) {
    var data = JSON.parse(localStorage[this._dbName]);
    var todos = data.todos;

    callback = callback || function () {};

    // If an ID was actually given, find the item and update each property
    if (typeof id !== 'object') {
    for (var i = 0; i < todos.length; i++) {
    if (todos[i].id == id) {
    for (var x in updateData) {
    todos[i][x] = updateData[x];
    }
    }
    }

    localStorage[this._dbName] = JSON.stringify(data);
    callback.call(this, JSON.parse(localStorage[this._dbName]).todos);
    } else {
    callback = updateData;

    updateData = id;

    // Generate an ID
    updateData.id = new Date().getTime();

    todos.push(updateData);
    localStorage[this._dbName] = JSON.stringify(data);
    callback.call(this, [updateData]);
    }
    };

    /**
     * Will remove an item from the Store based on its ID
     *
     * @param {number} id The ID of the item you want to remove
     * @param {function} callback The callback to fire after saving
     */
    Store.prototype.remove = function (id, callback) {
    var data = JSON.parse(localStorage[this._dbName]);
    var todos = data.todos;

    for (var i = 0; i < todos.length; i++) {
    if (todos[i].id == id) {
    todos.splice(i, 1);
    break;
    }
    }

    localStorage[this._dbName] = JSON.stringify(data);
    callback.call(this, JSON.parse(localStorage[this._dbName]).todos);
    };

    /**
     * Will drop all storage and start fresh
     *
     * @param {function} callback The callback to fire after dropping the data
     */
    Store.prototype.drop = function (callback) {
    localStorage[this._dbName] = JSON.stringify({todos: []});
    callback.call(this, JSON.parse(localStorage[this._dbName]).todos);
    };

    // Export to window
    window.app.Store = Store;
})(window);