Adding ChromeVox as a component extensions (enabled only for ChromeOS, for no...

chrome/browser/resources/access_chromevox/scripts/instant.js

+// Copyright (c) 2011 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+goog.provide('cvox.ChromeVoxInstantSearch');
+
+goog.require('cvox.ChromeVox');
+
+/**
+ * @fileoverview Script for enhancing Google Instant Search.
+ */
+cvox.ChromeVoxInstantSearch = { };
+
+/**
+ * @type {boolean}
+ */
+cvox.ChromeVoxInstantSearch.speakFirstResult = false;
+
+/**
+ * @type {number}
+ */
+cvox.ChromeVoxInstantSearch.updateDelay = 2000;
+
+/**
+ * @type {number}
+ */
+cvox.ChromeVoxInstantSearch.updateTime = new Date().getTime() +
+    cvox.ChromeVoxInstantSearch.updateDelay;
+
+/**
+ * @type {Object}
+ */
+cvox.ChromeVoxInstantSearch.previousSnippetNode = null;
+
+/**
+ * Initializes the Psychic Search script.
+ */
+cvox.ChromeVoxInstantSearch.init = function() {
+  var headID = document.getElementsByTagName('head')[0];
+  var cssNode = document.createElement('style');
+  cssNode.type = 'text/css';
+  cssNode.innerHTML = '#knavm-container {font-size: 150%}';
+  headID.appendChild(cssNode);
+
+  window.addEventListener('DOMSubtreeModified',
+      cvox.ChromeVoxInstantSearch.domSubtreeModified, true);
+  window.setTimeout(cvox.ChromeVoxInstantSearch.processUpdateQueue, 200);
+};
+
+/**
+ * Goes to the current result with the chevron arrow pointed at it and
+ * speaks it if it wasn't just spoken. Returns true if it was able to
+ * find such a result and speak it.
+ *
+ * @return {boolean} whether or not it was able to find and speak the
+ * current result on the page.
+ */
+cvox.ChromeVoxInstantSearch.gotoCurrentResult = function() {
+  var currentChevronNode = document.getElementById('knavm');
+  if (currentChevronNode) {
+    currentResultNode = currentChevronNode.parentNode;
+    if (currentResultNode != cvox.ChromeVoxInstantSearch.previousSnippetNode) {
+      var containerNode = document.getElementById('knavm-container');
+      if (containerNode != null) {
+        containerNode.id = '';
+      }
+      currentResultNode.id = 'knavm-container';
+      cvox.ChromeVoxInstantSearch.previousSnippetNode = currentResultNode;
+      var resultText = cvox.DomUtil.getText(currentResultNode);
+      // Use a setTimeout here so we don't get clobbered by the focus event.
+      window.setTimeout(function() {
+            cvox.ChromeVox.tts.speak(resultText, 0, null);
+          }, 0);
+      if (currentResultNode.previousSibling) {
+        cvox.ChromeVox.navigationManager.syncToNode(
+            currentResultNode.previousSibling);
+      } else {
+        // Sync to the top of the results section.
+        cvox.ChromeVox.navigationManager.syncToNode(
+            document.getElementById('subform_ctrl'));
+      }
+      return true;
+    }
+  }
+  return false;
+};
+
+/**
+ * Speaks when the user is moving through the results with the highlight
+ * and when the user is moving through suggestions.
+ *
+ * @param {Object} evt The DOMSubtreeModified event used to determine when
+ * there is a user action that we should respond to.
+ */
+cvox.ChromeVoxInstantSearch.domSubtreeModified = function(evt) {
+  if (cvox.ChromeVoxInstantSearch.gotoCurrentResult()) {
+    return;
+  }
+  var target = evt.target;
+  if (target.className &&
+      (target.className == 'gac_b')) {
+    var completion = target.getElementsByClassName('gac_c')[0];
+    cvox.ChromeVox.tts.speak(completion.textContent, 0, null);
+    cvox.ChromeVoxInstantSearch.speakFirstResult = true;
+    cvox.ChromeVoxInstantSearch.updateTime = new Date().getTime() +
+        cvox.ChromeVoxInstantSearch.updateDelay;
+  }
+};
+
+/**
+ * Speaks the first result when the results area is updated.
+ */
+cvox.ChromeVoxInstantSearch.processUpdateQueue = function() {
+  var resultsNode = document.getElementById('ires');
+  var results = resultsNode.getElementsByTagName('li');
+  if (results.length > 0) {
+    if ((cvox.ChromeVoxInstantSearch.speakFirstResult) &&
+        (new Date().getTime() > cvox.ChromeVoxInstantSearch.updateTime)) {
+      var resultText = cvox.DomUtil.getText(results[0]);
+      cvox.ChromeVox.tts.speak(resultText, 0, null);
+      cvox.ChromeVoxInstantSearch.speakFirstResult = false;
+    }
+  }
+  window.setTimeout(cvox.ChromeVoxInstantSearch.processUpdateQueue, 200);
+};
+
+window.setTimeout(cvox.ChromeVoxInstantSearch.init, 500);