/lib/MS Silk/Scripts/Debug/mstats.pubsub.js

//===================================================================================

// Microsoft patterns & practices

// Silk : Web Client Guidance

//===================================================================================

// Copyright (c) Microsoft Corporation.  All rights reserved.

// THIS CODE AND INFORMATION IS PROVIDED "AS IS" WITHOUT WARRANTY

// OF ANY KIND, EITHER EXPRESSED OR IMPLIED, INCLUDING BUT NOT

// LIMITED TO THE IMPLIED WARRANTIES OF MERCHANTABILITY AND

// FITNESS FOR A PARTICULAR PURPOSE.

//===================================================================================

// The example companies, organizations, products, domain names,

// e-mail addresses, logos, people, places, and events depicted

// herein are fictitious.  No association with any real company,

// organization, product, domain name, email address, logo, person,

// places, or events is intended or should be inferred.

//===================================================================================

/*jslint onevar: true, undef: true, newcap: true, regexp: true, plusplus: true, bitwise: true, devel: true, maxerr: 50 */

/*global jQuery, setInterval, clearInterval */



(function (mstats, $) {

    /**

    * PubSub is the messaging system used by 

    * the widgets to listen for and fire events

    */

    mstats.pubsub = (function () {

        var queue = [],

            that = {};



        /**

        * Executes all callbacks associated with eventName using the 

        * context provided in the subscription.

        *

        * @param {string} eventName  The name of the event to publish

        *                            Uses a dot notation for consistency

        * @param {object} data       Any data to be passed to the event

        *                            handler. Custom to the event.

        */



        that.publish = function (eventName, data) {

            var context, intervalId, idx = 0;

            if (queue[eventName]) {

                intervalId = setInterval(function () {

                    if (queue[eventName][idx]) {

                        context = queue[eventName][idx].context || this;

                        queue[eventName][idx].callback.call(context, data);

                        idx += 1;

                    } else {

                        clearInterval(intervalId);

                    }

                }, 0);



            }

        };

        /**

        * Stores an event subscription. Subsequent event subscriptions

        * are always added (not overwritten). Use unsubscribe to remove

        * event subscriptions.

        *

        * @param {string} eventName  The name of the event to publish

        *                            Uses a dot notation for consistency

        * @param {function} callback The function to be called when the 

        *                            event is published.

        * @param {object} context    The context to execute the callback

        */

        that.subscribe = function (eventName, callback, context) {

            if (!queue[eventName]) {

                queue[eventName] = [];

            }

            queue[eventName].push({

                callback: callback,

                context: context

            });

        };

        /**

        * Removes an event subscription.

        *

        * @param {string} eventName  The name of the event to remove

        * @param {function} callback The function associated witht the

        *                            event. Used to ensure the correct

        *                            event is being removed.

        * @param {object} context    The context associated with the 

        *                            callback. Used to ensure the correct

        *                            event is being removed.

        */

        that.unsubscribe = function (eventName, callback, context) {

            if (queue[eventName]) {

                queue[eventName].pop({

                    callback: callback,

                    context: context

                });

            }

        };



        return that;

    } ());



} (this.mstats = this.mstats || {}, jQuery));