/**
+ * @class Ext.util.TaskRunner
+ * Provides the ability to execute one or more arbitrary tasks in a multithreaded
+ * manner. Generally, you can use the singleton {@link Ext.TaskManager} instead, but
+ * if needed, you can create separate instances of TaskRunner. Any number of
+ * separate tasks can be started at any time and will run independently of each
+ * other. Example usage:
+ * <pre><code>
+// Start a simple clock task that updates a div once per second
+var updateClock = function(){
+ Ext.fly('clock').update(new Date().format('g:i:s A'));
+}
+var task = {
+ run: updateClock,
+ interval: 1000 //1 second
+}
+var runner = new Ext.util.TaskRunner();
+runner.start(task);
+
+// equivalent using TaskManager
+Ext.TaskManager.start({
+ run: updateClock,
+ interval: 1000
+});
+
+ * </code></pre>
+ * <p>See the {@link #start} method for details about how to configure a task object.</p>
+ * Also see {@link Ext.util.DelayedTask}.
+ *
+ * @constructor
+ * @param {Number} interval (optional) The minimum precision in milliseconds supported by this TaskRunner instance
+ * (defaults to 10)
+ */
+Ext.ns('Ext.util');
+
+Ext.util.TaskRunner = function(interval) {
+ interval = interval || 10;
+ var tasks = [],
+ removeQueue = [],
+ id = 0,
+ running = false,
+
+ // private
+ stopThread = function() {
+ running = false;
+ clearInterval(id);
+ id = 0;
+ },
+
+ // private
+ startThread = function() {
+ if (!running) {
+ running = true;
+ id = setInterval(runTasks, interval);
+ }
+ },
+
+ // private
+ removeTask = function(t) {
+ removeQueue.push(t);
+ if (t.onStop) {
+ t.onStop.apply(t.scope || t);
+ }
+ },
+
+ // private
+ runTasks = function() {
+ var rqLen = removeQueue.length,
+ now = new Date().getTime(),
+ i;
+
+ if (rqLen > 0) {
+ for (i = 0; i < rqLen; i++) {
+ Ext.Array.remove(tasks, removeQueue[i]);
+ }
+ removeQueue = [];
+ if (tasks.length < 1) {
+ stopThread();
+ return;
+ }
+ }
+ i = 0;
+ var t,
+ itime,
+ rt,
+ len = tasks.length;
+ for (; i < len; ++i) {
+ t = tasks[i];
+ itime = now - t.taskRunTime;
+ if (t.interval <= itime) {
+ rt = t.run.apply(t.scope || t, t.args || [++t.taskRunCount]);
+ t.taskRunTime = now;
+ if (rt === false || t.taskRunCount === t.repeat) {
+ removeTask(t);
+ return;
+ }
+ }
+ if (t.duration && t.duration <= (now - t.taskStartTime)) {
+ removeTask(t);
+ }
+ }
+ };
+
+ /**
+ * Starts a new task.
+ * @method start
+ * @param {Object} task <p>A config object that supports the following properties:<ul>
+ * <li><code>run</code> : Function<div class="sub-desc"><p>The function to execute each time the task is invoked. The
+ * function will be called at each interval and passed the <code>args</code> argument if specified, and the
+ * current invocation count if not.</p>
+ * <p>If a particular scope (<code>this</code> reference) is required, be sure to specify it using the <code>scope</code> argument.</p>
+ * <p>Return <code>false</code> from this function to terminate the task.</p></div></li>
+ * <li><code>interval</code> : Number<div class="sub-desc">The frequency in milliseconds with which the task
+ * should be invoked.</div></li>
+ * <li><code>args</code> : Array<div class="sub-desc">(optional) An array of arguments to be passed to the function
+ * specified by <code>run</code>. If not specified, the current invocation count is passed.</div></li>
+ * <li><code>scope</code> : Object<div class="sub-desc">(optional) The scope (<tt>this</tt> reference) in which to execute the
+ * <code>run</code> function. Defaults to the task config object.</div></li>
+ * <li><code>duration</code> : Number<div class="sub-desc">(optional) The length of time in milliseconds to invoke
+ * the task before stopping automatically (defaults to indefinite).</div></li>
+ * <li><code>repeat</code> : Number<div class="sub-desc">(optional) The number of times to invoke the task before
+ * stopping automatically (defaults to indefinite).</div></li>
+ * </ul></p>
+ * <p>Before each invocation, Ext injects the property <code>taskRunCount</code> into the task object so
+ * that calculations based on the repeat count can be performed.</p>
+ * @return {Object} The task
+ */
+ this.start = function(task) {
+ tasks.push(task);
+ task.taskStartTime = new Date().getTime();
+ task.taskRunTime = 0;
+ task.taskRunCount = 0;
+ startThread();
+ return task;
+ };
+
+ /**
+ * Stops an existing running task.
+ * @method stop
+ * @param {Object} task The task to stop
+ * @return {Object} The task
+ */
+ this.stop = function(task) {
+ removeTask(task);
+ return task;
+ };
+
+ /**
+ * Stops all tasks that are currently running.
+ * @method stopAll
+ */
+ this.stopAll = function() {
+ stopThread();
+ for (var i = 0, len = tasks.length; i < len; i++) {
+ if (tasks[i].onStop) {
+ tasks[i].onStop();
+ }
+ }
+ tasks = [];
+ removeQueue = [];
+ };
+};
+
+/**
+ * @class Ext.TaskManager
+ * @extends Ext.util.TaskRunner
+ * A static {@link Ext.util.TaskRunner} instance that can be used to start and stop arbitrary tasks. See
+ * {@link Ext.util.TaskRunner} for supported methods and task config properties.
+ * <pre><code>
+// Start a simple clock task that updates a div once per second
+var task = {
+ run: function(){
+ Ext.fly('clock').update(new Date().format('g:i:s A'));
+ },
+ interval: 1000 //1 second
+}
+Ext.TaskManager.start(task);
+</code></pre>
+ * <p>See the {@link #start} method for details about how to configure a task object.</p>
+ * @singleton
+ */
+Ext.TaskManager = Ext.create('Ext.util.TaskRunner');