[Switch Access] Clean up AutoScanManager

There have been a few major refactors of Switch Access recently. This
change looks at AutoScanManager and cleans up things that are now
overly complex, or need adjusting.

Bug: None
Change-Id: Ic77fb49a143ce91ff90099f773f613bd2f9e55ff
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2056502Reviewed-by: Katie Dektar <katie@chromium.org>
Commit-Queue: Anastasia Helfinstein <anastasi@google.com>
Cr-Commit-Position: refs/heads/master@{#742777}

chrome/browser/resources/chromeos/accessibility/switch_access/auto_scan_manager.js

@@ -6,38 +6,63 @@
  * Class to handle auto-scan behavior.
  */
 class AutoScanManager {
+  /** @private */
+  constructor() {
+    /**
+     * Auto-scan interval ID.
+     * @private {number|undefined}
+     */
+    this.intervalID_;
+
+    /**
+     * Length of the auto-scan interval for most contexts, in milliseconds.
+     * @private {number}
+     */
+    this.primaryScanTime_ = AutoScanManager.NOT_INITIALIZED;
+
+    /**
+     * Length of auto-scan interval for the on-screen keyboard in milliseconds.
+     * @private {number}
+     */
+    this.keyboardScanTime_ = AutoScanManager.NOT_INITIALIZED;
+
+    /**
+     * Whether auto-scanning is enabled.
+     * @private {boolean}
+     */
+    this.isEnabled_ = false;
+
+    /**
+     * Whether the current node is within the virtual keyboard.
+     * @private {boolean}
+     */
+    this.inKeyboard_ = false;
+  }
+
   // ============== Static Methods ================
 
   static initialize() {
     AutoScanManager.instance = new AutoScanManager();
   }
 
-  /**
-   * Return true if auto-scan is currently running. Otherwise return false.
-   * @return {boolean}
-   */
-  static isRunning() {
-    return AutoScanManager.instance.isEnabled_;
-  }
-
   /**
    * Restart auto-scan under the current settings if it is currently running.
    */
   static restartIfRunning() {
-    if (AutoScanManager.isRunning()) {
+    if (AutoScanManager.instance.isRunning_()) {
       AutoScanManager.instance.stop_();
       AutoScanManager.instance.start_();
     }
   }
 
   /**
-   * Update this.defaultScanTime_ to |scanTime|. Then, if auto-scan is currently
+   * Update this.primaryScanTime_ to |scanTime|. Then, if auto-scan is currently
    * running, restart it.
    *
    * @param {number} scanTime Auto-scan interval time in milliseconds.
    */
-  static setDefaultScanTime(scanTime) {
-    AutoScanManager.instance.defaultScanTime_ = scanTime;
+  static setPrimaryScanTime(scanTime) {
+    AutoScanManager.instance.primaryScanTime_ = scanTime;
     AutoScanManager.restartIfRunning();
   }
 
@@ -48,7 +73,7 @@ class AutoScanManager {
    * @param {boolean} enabled
    */
   static setEnabled(enabled) {
-    if (AutoScanManager.isRunning()) {
+    if (AutoScanManager.instance.isRunning_()) {
       AutoScanManager.instance.stop_();
     }
     AutoScanManager.instance.isEnabled_ = enabled;
@@ -79,54 +104,31 @@ class AutoScanManager {
 
   // ============== Private Methods ================
 
-  /** @private */
-  constructor() {
-    /**
-     * Auto-scan interval ID.
-     * @private {number|undefined}
-     */
-    this.intervalID_;
-
-    /**
-     * Length of the default auto-scan interval (used wherever there is not
-     * a more specific scan time set) in milliseconds.
-     * @private {number}
-     */
-    this.defaultScanTime_ = AutoScanManager.NOT_INITIALIZED;
-
-    /**
-     * Length of auto-scan interval for the on-screen keyboard in milliseconds.
-     * @private {number}
-     */
-    this.keyboardScanTime_ = AutoScanManager.NOT_INITIALIZED;
-
-    /**
-     * Whether auto-scanning is enabled.
-     * @private {boolean}
-     */
-    this.isEnabled_ = false;
-
-    /**
-     * Whether the current node is within the virtual keyboard.
-     * @private {boolean}
-     */
-    this.inKeyboard_ = false;
+  /**
+   * Return true if auto-scan is currently running. Otherwise return false.
+   * @return {boolean}
+   * @private
+   */
+  isRunning_() {
+    return AutoScanManager.instance.isEnabled_;
   }
 
   /**
    * Set the window to move to the next node at an interval in milliseconds
    * depending on where the user is navigating. Currently,
    * this.keyboardScanTime_ is used as the interval if the user is
-   * navigating in the virtual keyboard, and this.defaultScanTime_ is used
-   * otherwise.
+   * navigating in the virtual keyboard, and this.primaryScanTime_ is used
+   * otherwise. Does not do anything if AutoScanManager is already scanning.
+   *
    * @private
    */
   start_() {
-    if (this.defaultScanTime_ === AutoScanManager.NOT_INITIALIZED) {
+    if (this.primaryScanTime_ === AutoScanManager.NOT_INITIALIZED ||
+        this.intervalID_) {
       return;
     }
 
-    let currentScanTime = this.defaultScanTime_;
+    let currentScanTime = this.primaryScanTime_;
 
     if (SwitchAccess.instance.improvedTextInputEnabled() && this.inKeyboard_ &&
         this.keyboardScanTime_ !== AutoScanManager.NOT_INITIALIZED) {

chrome/browser/resources/chromeos/accessibility/switch_access/auto_scan_manager_test.js

@@ -57,7 +57,7 @@ TEST_F('SwitchAccessAutoScanManagerTest', 'SetEnabled', function() {
   this.runWithLoadedTree('', (desktop) => {
     console.error('RUNNING TEST');
     assertFalse(
-        AutoScanManager.isRunning(),
+        AutoScanManager.instance.isRunning_(),
         'Auto scan manager is running prematurely');
     assertEquals(
         0, NavigationManager.moveForwardCount,
@@ -67,7 +67,8 @@ TEST_F('SwitchAccessAutoScanManagerTest', 'SetEnabled', function() {
     NavigationManager.instance
         .onMoveForwardForTesting_ = this.newCallback(() => {
       assertTrue(
-          AutoScanManager.isRunning(), 'Auto scan manager has stopped running');
+          AutoScanManager.instance.isRunning_(),
+          'Auto scan manager has stopped running');
       assertGT(
           NavigationManager.moveForwardCount, 0,
           'Switch Access has not moved forward');
@@ -76,7 +77,9 @@ TEST_F('SwitchAccessAutoScanManagerTest', 'SetEnabled', function() {
     });
 
     AutoScanManager.setEnabled(true);
-    assertTrue(AutoScanManager.isRunning(), 'Auto scan manager is not running');
+    assertTrue(
+        AutoScanManager.instance.isRunning_(),
+        'Auto scan manager is not running');
     assertEquals(1, intervalCount, 'There is not exactly 1 interval');
   });
 });
@@ -84,7 +87,7 @@ TEST_F('SwitchAccessAutoScanManagerTest', 'SetEnabled', function() {
 TEST_F('SwitchAccessAutoScanManagerTest', 'SetEnabledMultiple', function() {
   this.runWithLoadedTree('', (desktop) => {
     assertFalse(
-        AutoScanManager.isRunning(),
+        AutoScanManager.instance.isRunning_(),
         'Auto scan manager is running prematurely');
     assertEquals(0, intervalCount, 'Incorrect initialization of intervalCount');
 
@@ -92,7 +95,9 @@ TEST_F('SwitchAccessAutoScanManagerTest', 'SetEnabledMultiple', function() {
     AutoScanManager.setEnabled(true);
     AutoScanManager.setEnabled(true);
 
-    assertTrue(AutoScanManager.isRunning(), 'Auto scan manager is not running');
+    assertTrue(
+        AutoScanManager.instance.isRunning_(),
+        'Auto scan manager is not running');
     assertEquals(1, intervalCount, 'There is not exactly 1 interval');
   });
 });
@@ -100,17 +105,20 @@ TEST_F('SwitchAccessAutoScanManagerTest', 'SetEnabledMultiple', function() {
 TEST_F('SwitchAccessAutoScanManagerTest', 'EnableAndDisable', function() {
   this.runWithLoadedTree('', (desktop) => {
     assertFalse(
-        AutoScanManager.isRunning(),
+        AutoScanManager.instance.isRunning_(),
         'Auto scan manager is running prematurely');
     assertEquals(0, intervalCount, 'Incorrect initialization of intervalCount');
 
     AutoScanManager.setEnabled(true);
-    assertTrue(AutoScanManager.isRunning(), 'Auto scan manager is not running');
+    assertTrue(
+        AutoScanManager.instance.isRunning_(),
+        'Auto scan manager is not running');
     assertEquals(1, intervalCount, 'There is not exactly 1 interval');
 
     AutoScanManager.setEnabled(false);
     assertFalse(
-        AutoScanManager.isRunning(), 'Auto scan manager did not stop running');
+        AutoScanManager.instance.isRunning_(),
+        'Auto scan manager did not stop running');
     assertEquals(0, intervalCount, 'Interval was not removed');
   });
 });
@@ -119,7 +127,7 @@ TEST_F(
     'SwitchAccessAutoScanManagerTest', 'RestartIfRunningMultiple', function() {
       this.runWithLoadedTree('', (desktop) => {
         assertFalse(
-            AutoScanManager.isRunning(),
+            AutoScanManager.instance.isRunning_(),
             'Auto scan manager is running prematurely');
         assertEquals(
             0, NavigationManager.moveForwardCount,
@@ -133,7 +141,8 @@ TEST_F(
         AutoScanManager.restartIfRunning();
 
         assertTrue(
-            AutoScanManager.isRunning(), 'Auto scan manager is not running');
+            AutoScanManager.instance.isRunning_(),
+            'Auto scan manager is not running');
         assertEquals(1, intervalCount, 'There is not exactly 1 interval');
       });
     });
@@ -142,46 +151,47 @@ TEST_F(
     'SwitchAccessAutoScanManagerTest', 'RestartIfRunningWhenOff', function() {
       this.runWithLoadedTree('', (desktop) => {
         assertFalse(
-            AutoScanManager.isRunning(),
+            AutoScanManager.instance.isRunning_(),
             'Auto scan manager is running at start.');
         AutoScanManager.restartIfRunning();
         assertFalse(
-            AutoScanManager.isRunning(),
+            AutoScanManager.instance.isRunning_(),
             'Auto scan manager enabled by restartIfRunning');
       });
     });
 
-TEST_F('SwitchAccessAutoScanManagerTest', 'SetDefaultScanTime', function() {
+TEST_F('SwitchAccessAutoScanManagerTest', 'SetPrimaryScanTime', function() {
   this.runWithLoadedTree('', (desktop) => {
     assertFalse(
-        AutoScanManager.isRunning(),
+        AutoScanManager.instance.isRunning_(),
         'Auto scan manager is running prematurely');
     assertEquals(
         UNDEFINED_INTERVAL_DELAY, intervalDelay,
         'Interval delay improperly initialized');
 
-    AutoScanManager.setDefaultScanTime(2);
+    AutoScanManager.setPrimaryScanTime(2);
     assertFalse(
-        AutoScanManager.isRunning(),
+        AutoScanManager.instance.isRunning_(),
         'Setting default scan time started auto-scanning');
     assertEquals(
-        2, AutoScanManager.instance.defaultScanTime_,
+        2, AutoScanManager.instance.primaryScanTime_,
         'Default scan time set improperly');
     assertEquals(
         UNDEFINED_INTERVAL_DELAY, intervalDelay,
         'Interval delay set prematurely');
 
     AutoScanManager.setEnabled(true);
-    assertTrue(AutoScanManager.isRunning(), 'Auto scan did not start');
+    assertTrue(
+        AutoScanManager.instance.isRunning_(), 'Auto scan did not start');
     assertEquals(
-        2, AutoScanManager.instance.defaultScanTime_,
+        2, AutoScanManager.instance.primaryScanTime_,
         'Default scan time has changed');
     assertEquals(2, intervalDelay, 'Interval delay not set');
 
-    AutoScanManager.setDefaultScanTime(5);
-    assertTrue(AutoScanManager.isRunning(), 'Auto scan stopped');
+    AutoScanManager.setPrimaryScanTime(5);
+    assertTrue(AutoScanManager.instance.isRunning_(), 'Auto scan stopped');
     assertEquals(
-        5, AutoScanManager.instance.defaultScanTime_,
+        5, AutoScanManager.instance.primaryScanTime_,
         'Default scan time did not change when set a second time');
     assertEquals(5, intervalDelay, 'Interval delay did not update');
   });

chrome/browser/resources/chromeos/accessibility/switch_access/nodes/keyboard_node.js

@@ -102,6 +102,7 @@ class KeyboardRootNode extends RootNodeWrapper {
   /** @override */
   onExit() {
     chrome.accessibilityPrivate.setVirtualKeyboardVisible(false);
+    AutoScanManager.setInKeyboard(false);
   }
 
   // ================= Static methods =================
@@ -113,6 +114,7 @@ class KeyboardRootNode extends RootNodeWrapper {
    */
   static buildTree(desktop) {
     KeyboardRootNode.loadKeyboard_();
+    AutoScanManager.setInKeyboard(true);
 
     const keyboardContainer =
         desktop.find({role: chrome.automation.RoleType.KEYBOARD});

chrome/browser/resources/chromeos/accessibility/switch_access/preferences.js

@@ -92,7 +92,7 @@ class SwitchAccessPreferences {
             break;
           case SAConstants.Preference.AUTO_SCAN_TIME:
             if (pref.type === chrome.settingsPrivate.PrefType.NUMBER) {
-              AutoScanManager.setDefaultScanTime(
+              AutoScanManager.setPrimaryScanTime(
                   /** @type {number} */ (pref.value));
             }
             break;