From c013a531cfdd93da8f9b4f294498c6255c9927ca Mon Sep 17 00:00:00 2001
From: Andrey Lushnikov <lushnikov@chromium.org>
Date: Sat, 29 Jul 2017 19:12:17 -0700
Subject: [PATCH] Refactor EmulationManager

This patch refactors EmulationManager so that it is a normal
class with a state.
---
 lib/EmulationManager.js | 40 +++++++++++++++++++++-------------------
 lib/Page.js             | 28 +++++++++-------------------
 2 files changed, 30 insertions(+), 38 deletions(-)

diff --git a/lib/EmulationManager.js b/lib/EmulationManager.js
index 9c851ecc97d..d5763770c63 100644
--- a/lib/EmulationManager.js
+++ b/lib/EmulationManager.js
@@ -17,41 +17,47 @@
 class EmulationManager {
   /**
    * @param {!Connection} client
+   */
+  constructor(client) {
+    this._client = client;
+    this._emulatingMobile = false;
+    this._injectedTouchScriptId = null;
+  }
+
+  /**
    * @param {!Page.Viewport} viewport
    * @return {Promise<boolean>}
    */
-  static async emulateViewport(client, viewport) {
+  async emulateViewport(client, viewport) {
     const mobile = viewport.isMobile || false;
-    const landscape = viewport.isLandscape || false;
     const width = viewport.width;
     const height = viewport.height;
     const deviceScaleFactor = viewport.deviceScaleFactor || 1;
-    const screenOrientation = landscape ? { angle: 90, type: 'landscapePrimary' } : { angle: 0, type: 'portraitPrimary' };
+    const screenOrientation = viewport.isLandscape ? { angle: 90, type: 'landscapePrimary' } : { angle: 0, type: 'portraitPrimary' };
 
     await Promise.all([
-      client.send('Emulation.setDeviceMetricsOverride', { mobile, width, height, deviceScaleFactor, screenOrientation }),
-      client.send('Emulation.setTouchEmulationEnabled', {
+      this._client.send('Emulation.setDeviceMetricsOverride', { mobile, width, height, deviceScaleFactor, screenOrientation }),
+      this._client.send('Emulation.setTouchEmulationEnabled', {
         enabled: viewport.hasTouch || false,
         configuration: viewport.isMobile ? 'mobile' : 'desktop'
       })
     ]);
 
     let reloadNeeded = false;
-    if (viewport.hasTouch && !client[EmulationManager._touchScriptId]) {
+    if (viewport.hasTouch && !this._injectedTouchScriptId) {
       const source = `(${injectedTouchEventsFunction})()`;
-      client[EmulationManager._touchScriptId] = (await client.send('Page.addScriptToEvaluateOnNewDocument', { source })).identifier;
+      this._injectedTouchScriptId = (await this._client.send('Page.addScriptToEvaluateOnNewDocument', { source })).identifier;
+      reloadNeeded = true;
+    } else if (!viewport.hasTouch && this._injectedTouchScriptId) {
+      await this._client.send('Page.removeScriptToEvaluateOnNewDocument', {identifier: this._injectedTouchScriptId});
+      this._injectedTouchScriptId = null;
       reloadNeeded = true;
     }
 
-    if (!viewport.hasTouch && client[EmulationManager._touchScriptId]) {
-      await client.send('Page.removeScriptToEvaluateOnNewDocument', {identifier: client[EmulationManager._touchScriptId]});
-      client[EmulationManager._touchScriptId] = null;
+    if (this._emulatingMobile !== mobile)
       reloadNeeded = true;
-    }
-
-    if (client[EmulationManager._emulatingMobile] !== mobile)
-      reloadNeeded = true;
-    client[EmulationManager._emulatingMobile] = mobile;
+    this._emulatingMobile = mobile;
+    return reloadNeeded;
 
     function injectedTouchEventsFunction() {
       const touchEvents = ['ontouchstart', 'ontouchend', 'ontouchmove', 'ontouchcancel'];
@@ -66,11 +72,7 @@ class EmulationManager {
         }
       }
     }
-    return reloadNeeded;
   }
 }
 
-EmulationManager._touchScriptId = Symbol('emulatingTouchScriptId');
-EmulationManager._emulatingMobile = Symbol('emulatingMobile');
-
 module.exports = EmulationManager;
diff --git a/lib/Page.js b/lib/Page.js
index 708df3f1b35..660bb6c8304 100644
--- a/lib/Page.js
+++ b/lib/Page.js
@@ -38,36 +38,28 @@ class Page extends EventEmitter {
       client.send('Runtime.enable', {}),
       client.send('Security.enable', {}),
     ]);
-    const keyboard = new Keyboard(client);
-    const mouse = new Mouse(client, keyboard);
-    const frameManager = new FrameManager(client, mouse);
-    const networkManager = new NetworkManager(client);
-    const page = new Page(client, frameManager, networkManager, screenshotTaskQueue, mouse, keyboard);
+    const page = new Page(client, screenshotTaskQueue);
+    await page.navigate('about:blank');
     // Initialize default page size.
     await page.setViewport({width: 400, height: 300});
-    await page.navigate('about:blank');
     return page;
   }
 
   /**
    * @param {!Connection} client
-   * @param {!FrameManager} frameManager
-   * @param {!NetworkManager} networkManager
    * @param {!TaskQueue} screenshotTaskQueue
-   * @param {!Mouse} mouse
-   * @param {!Keyboard} keyboard
    */
-  constructor(client, frameManager, networkManager, screenshotTaskQueue, mouse, keyboard) {
+  constructor(client, screenshotTaskQueue) {
     super();
     this._client = client;
-    this._frameManager = frameManager;
-    this._networkManager = networkManager;
+    this._keyboard = new Keyboard(client);
+    this._mouse = new Mouse(client, this._keyboard);
+    this._frameManager = new FrameManager(client, this._mouse);
+    this._networkManager = new NetworkManager(client);
+    this._emulationManager = new EmulationManager(client);
     /** @type {!Map<string, function>} */
     this._inPageCallbacks = new Map();
 
-    this._keyboard = keyboard;
-    this._mouse = mouse;
-
     this._screenshotTaskQueue = screenshotTaskQueue;
 
     this._frameManager.on(FrameManager.Events.FrameAttached, event => this.emit(Page.Events.FrameAttached, event));
@@ -274,8 +266,6 @@ class Page extends EventEmitter {
    * @return {!Promise<?Response>}
    */
   async reload(options) {
-    if (!this.mainFrame())
-      return;
     this._client.send('Page.reload');
     return this.waitForNavigation(options);
   }
@@ -330,7 +320,7 @@ class Page extends EventEmitter {
    * @return {!Promise}
    */
   async setViewport(viewport) {
-    const needsReload = await EmulationManager.emulateViewport(this._client, viewport);
+    const needsReload = await this._emulationManager.emulateViewport(this._client, viewport);
     this._viewport = viewport;
     if (needsReload)
       await this.reload();