DevTools: extract TracingManager from TracingModel, step 2

Source/devtools/front_end/sdk/TracingManager.js

+/*
+ * Copyright 2014 The Chromium Authors. All rights reserved.

[yurys, 2014/09/11 06:49:23]

nit: I guess we use // -style comments for license header in most of the places

+ * Use of this source code is governed by a BSD-style license that can be
+ * found in the LICENSE file.
+ */
+
+/**
+ * @constructor
+ * @extends {WebInspector.Object}
+ * @implements {WebInspector.TargetManager.Observer}
+ */
+WebInspector.TracingManager = function()
+{
+    WebInspector.Object.call(this);
+    this._active = false;
+    WebInspector.targetManager.observeTargets(this);
+}
+
+WebInspector.TracingManager.Events = {
+    "BufferUsage": "BufferUsage",
+    "TracingStarted": "TracingStarted",
+    "EventsCollected": "EventsCollected",
+    "TracingStopped": "TracingStopped",
+    "TracingComplete": "TracingComplete"
+}
+
+/** @typedef {!{
+        cat: string,
+        pid: number,
+        tid: number,
+        ts: number,
+        ph: string,
+        name: string,
+        args: !Object,
+        dur: number,
+        id: number,
+        s: string
+    }}
+ */
+WebInspector.TracingManager.EventPayload;
+
+WebInspector.TracingManager.prototype = {
+    /**
+     * @param {!WebInspector.Target} target
+     */
+    targetAdded: function(target)
+    {
+        if (this._target)
+            return;
+        this._target = target;
+        InspectorBackend.registerTracingDispatcher(new WebInspector.TracingDispatcher(this));
+    },
+
+    /**
+     * @param {!WebInspector.Target} target
+     */
+    targetRemoved: function(target)
+    {
+        if (this._target !== target)
+            return;
+        delete this._target;
+    },
+
+    /**
+     * @param {number} usage
+     */
+    _bufferUsage: function(usage)
+    {
+        this.dispatchEventToListeners(WebInspector.TracingManager.Events.BufferUsage, usage);
+    },
+
+    /**
+     * @param {!Array.<!WebInspector.TracingManager.EventPayload>} events
+     */
+    _eventsCollected: function(events)
+    {
+        this.dispatchEventToListeners(WebInspector.TracingManager.Events.EventsCollected, events);
+    },
+
+    _tracingComplete: function()
+    {
+        this.dispatchEventToListeners(WebInspector.TracingManager.Events.TracingComplete);
+    },
+
+    _tracingStarted: function()
+    {
+        if (this._active)
+            return;
+        this._active = true;
+        this.dispatchEventToListeners(WebInspector.TracingManager.Events.TracingStarted);
+    },
+
+    /**
+     * @param {string} categoryFilter
+     * @param {string} options
+     * @param {function(?string)=} callback
+     */
+    start: function(categoryFilter, options, callback)
+    {
+        if (this._active)
+            return;
+        WebInspector.profilingLock().acquire();
+        this._shouldReleaseLock = true;
+        var bufferUsageReportingIntervalMs = 500;
+        TracingAgent.start(categoryFilter, options, bufferUsageReportingIntervalMs, callback);
+        this._tracingStarted();
+        this._active = true;
+    },
+
+    stop: function()
+    {
+        if (!this._active)
+            return;
+        TracingAgent.end(this._onStop.bind(this));
+        if (this._shouldReleaseLock) {
+            this._shouldReleaseLock = false;
+            WebInspector.profilingLock().release();
+        }
+    },
+
+    _onStop: function()
+    {
+        if (!this._active)
+            return;
+        this.dispatchEventToListeners(WebInspector.TracingManager.Events.TracingStopped);
+        this._active = false;
+    },
+
+    __proto__: WebInspector.Object.prototype
+}
+
+/**
+ * @constructor
+ * @implements {TracingAgent.Dispatcher}
+ * @param {!WebInspector.TracingManager} tracingManager
+ */
+WebInspector.TracingDispatcher = function(tracingManager)
+{
+    this._tracingManager = tracingManager;
+}
+
+WebInspector.TracingDispatcher.prototype = {
+    /**
+     * @param {number} usage
+     */
+    bufferUsage: function(usage)
+    {
+        this._tracingManager._bufferUsage(usage);
+    },
+
+    /**
+     * @param {!Array.<!WebInspector.TracingManager.EventPayload>} data
+     */
+    dataCollected: function(data)
+    {
+        this._tracingManager._eventsCollected(data);
+    },
+
+    tracingComplete: function()
+    {
+        this._tracingManager._tracingComplete();
+    },
+
+    started: function()
+    {
+        this._tracingManager._tracingStarted();
+    }
+}