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

chrome/browser/resources/access_chromevox/chromevox/injected/tools/search.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.
+
+/**
+ * @fileoverview JavaScript for poppup up a search widget and performing
+ * search within a page.
+ */
+
+goog.provide('cvox.ChromeVoxSearch');
+
+goog.require('cvox.AbstractEarcons');
+goog.require('cvox.ChromeVox');
+goog.require('cvox.SelectionUtil');
+goog.require('cvox.XpathUtil');
+
+/**
+ * @type {Object}
+ */
+cvox.ChromeVoxSearch.txtNode = null;
+
+/**
+ * @type {boolean}
+ */
+cvox.ChromeVoxSearch.active = false;
+
+/**
+ * @type {Array?}
+ */
+cvox.ChromeVoxSearch.matchNodes = null;
+
+/**
+ * @type {number?}
+ */
+cvox.ChromeVoxSearch.matchNodesIndex = null;
+
+/**
+ * @type {boolean}
+ */
+cvox.ChromeVoxSearch.caseSensitive = false;
+
+/**
+ * Initializes the search widget.
+ */
+cvox.ChromeVoxSearch.init = function() {
+  cvox.ChromeVoxSearch.active = false;
+  cvox.ChromeVoxSearch.caseSensitive = false;
+  window.addEventListener('keypress', cvox.ChromeVoxSearch.processKeyPress,
+      true);
+  window.addEventListener('keydown', cvox.ChromeVoxSearch.processKeyDown,
+      true);
+  window.addEventListener('scroll', cvox.ChromeVoxSearch.scrollHandler,
+      true);
+};
+
+/**
+ * Returns whether or not the search widget is active.
+ *
+ * @return {boolean} True if the search widget is active.
+ */
+cvox.ChromeVoxSearch.isActive = function() {
+  return cvox.ChromeVoxSearch.active;
+};
+
+/**
+ * Displays the search widget.
+ */
+cvox.ChromeVoxSearch.show = function() {
+  cvox.ChromeVoxSearch.txtNode = document.createElement('div');
+  cvox.ChromeVoxSearch.txtNode.style['display'] = 'block';
+  cvox.ChromeVoxSearch.txtNode.style['position'] = 'absolute';
+  cvox.ChromeVoxSearch.txtNode.style['left'] = '2px';
+  cvox.ChromeVoxSearch.txtNode.style['top'] = (window.scrollY + 2) + 'px';
+  cvox.ChromeVoxSearch.txtNode.style['line-height'] = '1.2em';
+  cvox.ChromeVoxSearch.txtNode.style['z-index'] = '10001';
+  cvox.ChromeVoxSearch.txtNode.style['font-size'] = '20px';
+
+  document.body.insertBefore(cvox.ChromeVoxSearch.txtNode,
+      document.body.firstChild);
+  cvox.ChromeVoxSearch.active = true;
+};
+
+/**
+ * Keeps the search widget at the upperleft hand corner of the screen when
+ * the page scrolls.
+ */
+cvox.ChromeVoxSearch.scrollHandler = function() {
+  if (!cvox.ChromeVoxSearch.active) {
+    return;
+  }
+  cvox.ChromeVoxSearch.txtNode.style['top'] = (window.scrollY + 2) + 'px';
+};
+
+/**
+ * Handles the keyDown event when the search widget is active.
+ *
+ * @param {Object} evt The keyDown event.
+ * @return {boolean} Whether or not the event was handled.
+ */
+cvox.ChromeVoxSearch.processKeyDown = function(evt) {
+  if (!cvox.ChromeVoxSearch.active) {
+    return false;
+  }
+  if (evt.keyCode == 8) { // Backspace
+    var searchStr = cvox.ChromeVoxSearch.txtNode.textContent;
+    if (searchStr.length > 0) {
+      searchStr = searchStr.substring(searchStr, searchStr.length - 1);
+      cvox.ChromeVoxSearch.doSearch(searchStr,
+          cvox.ChromeVoxSearch.caseSensitive);
+    }
+    // Don't go to the previous page!
+    evt.preventDefault();
+    return true;
+  } else if (evt.keyCode == 40) { // Down arrow
+    cvox.ChromeVoxSearch.next();
+    return true;
+  } else if (evt.keyCode == 38) { // Up arrow
+    cvox.ChromeVoxSearch.prev();
+    return true;
+  } else if (evt.ctrlKey && evt.keyCode == 67) { // ctrl + c
+    cvox.ChromeVoxSearch.toggleCaseSensitivity();
+    return true;
+  }
+  return false;
+};
+
+/**
+ * Adds the letter the user typed to the search string and updates the search.
+ *
+ * @param {Object} evt The keyPress event.
+ * @return {boolean} Whether or not the event was handled.
+ */
+cvox.ChromeVoxSearch.processKeyPress = function(evt) {
+  if (!cvox.ChromeVoxSearch.active) {
+    return false;
+  }
+  var searchStr = cvox.ChromeVoxSearch.txtNode.textContent +
+      String.fromCharCode(evt.charCode);
+  cvox.ChromeVoxSearch.doSearch(searchStr,
+      cvox.ChromeVoxSearch.caseSensitive);
+  evt.preventDefault();
+  evt.stopPropagation();
+  return true;
+};
+
+/**
+ * Toggles whether or not searches are case sensitive.
+ */
+cvox.ChromeVoxSearch.toggleCaseSensitivity = function() {
+  if (cvox.ChromeVoxSearch.caseSensitive) {
+    cvox.ChromeVoxSearch.caseSensitive = false;
+    cvox.ChromeVox.tts.speak('Ignoring case', 0, null);
+  } else {
+    cvox.ChromeVoxSearch.caseSensitive = true;
+    cvox.ChromeVox.tts.speak('Case sensitive', 0, null);
+  }
+};
+
+/**
+ * Performs the search and highlights and speaks the first result.
+ *
+ * @param {String} searchStr The text to search for.
+ * @param {boolean} caseSensitive Whether or not the search is case sensitive.
+ */
+cvox.ChromeVoxSearch.doSearch = function(searchStr, caseSensitive) {
+  cvox.ChromeVoxSearch.txtNode.textContent = '';
+
+  cvox.ChromeVoxSearch.matchNodes = new Array();
+  var potentialMatchNodes;
+  if (caseSensitive) {
+    potentialMatchNodes = cvox.XpathUtil.evalXPath(
+        './/text()[contains(.,"' + searchStr + '")]',
+        document.body);
+  } else {
+    searchStr = searchStr.toLowerCase();
+    potentialMatchNodes = cvox.XpathUtil.evalXPath(
+        './/text()[contains(translate(., "ABCDEFGHIJKLMNOPQRSTUVWXYZ", ' +
+        '"abcdefghijklmnopqrstuvwxyz"), "' + searchStr + '")]',
+        document.body);
+  }
+  // Only accept nodes that are considered to have content.
+  for (var i = 0, node; node = potentialMatchNodes[i]; i++) {
+    if (cvox.DomUtil.hasContent(node)) {
+      cvox.ChromeVoxSearch.matchNodes.push(node);
+    }
+  }
+
+  var firstNode = cvox.ChromeVoxSearch.matchNodes[0];
+
+  if (firstNode) {
+    cvox.ChromeVoxSearch.matchNodesIndex = 0;
+    var startIndex = 0;
+    if (caseSensitive) {
+      startIndex = firstNode.textContent.indexOf(searchStr);
+    } else {
+      startIndex = firstNode.textContent.toLowerCase().indexOf(searchStr);
+    }
+    cvox.SelectionUtil.selectText(firstNode, startIndex,
+        startIndex + searchStr.length);
+    cvox.ChromeVox.traverseContent.moveNext('sentence');
+    var sel = window.getSelection();
+    var range = sel.getRangeAt(0);
+    range.setStart(firstNode, startIndex);
+    sel.removeAllRanges();
+    sel.addRange(range);
+    cvox.SelectionUtil.scrollToSelection(sel);
+    cvox.ChromeVox.tts.speak(window.getSelection() + '', 0, null);
+  } else {
+    // TODO (clchen): Replace this with an error sound once we have one defined.
+    cvox.ChromeVox.tts.stop();
+    cvox.ChromeVox.earcons.playEarcon(cvox.AbstractEarcons.WRAP);
+  }
+  cvox.ChromeVoxSearch.txtNode.textContent = searchStr;
+};
+
+/**
+ * Dismisses the search widget
+ */
+cvox.ChromeVoxSearch.hide = function() {
+  if (cvox.ChromeVoxSearch.active) {
+    cvox.ChromeVoxSearch.txtNode.parentNode.removeChild(
+        cvox.ChromeVoxSearch.txtNode);
+    cvox.ChromeVoxSearch.txtNode = null;
+    cvox.ChromeVoxSearch.active = false;
+  }
+};
+
+/**
+ * Goes to the next matching result, highlights it, and speaks it.
+ */
+cvox.ChromeVoxSearch.next = function() {
+  if (cvox.ChromeVoxSearch.matchNodes &&
+      (cvox.ChromeVoxSearch.matchNodes.length > 0)) {
+    cvox.ChromeVoxSearch.matchNodesIndex++;
+    if (cvox.ChromeVoxSearch.matchNodes.length >
+        cvox.ChromeVoxSearch.matchNodesIndex) {
+      var searchStr = cvox.ChromeVoxSearch.txtNode.textContent;
+      var targetNode = cvox.ChromeVoxSearch.matchNodes[
+          cvox.ChromeVoxSearch.matchNodesIndex];
+      var startIndex = 0;
+      if (cvox.ChromeVoxSearch.caseSensitive) {
+        startIndex = targetNode.textContent.indexOf(searchStr);
+      } else {
+        startIndex = targetNode.textContent.toLowerCase().indexOf(
+            searchStr.toLowerCase());
+      }
+      cvox.SelectionUtil.selectText(targetNode, startIndex,
+          startIndex + searchStr.length);
+      cvox.ChromeVox.traverseContent.moveNext('sentence');
+      var sel = window.getSelection();
+      var range = sel.getRangeAt(0);
+      range.setStart(targetNode, startIndex);
+      sel.removeAllRanges();
+      sel.addRange(range);
+      cvox.SelectionUtil.scrollToSelection(sel);
+      cvox.ChromeVox.tts.speak(window.getSelection() + '', 0, null);
+    } else {
+      cvox.ChromeVox.earcons.playEarcon(cvox.AbstractEarcons.WRAP);
+      cvox.ChromeVoxSearch.matchNodesIndex = -1;
+      cvox.ChromeVoxSearch.next();
+    }
+  }
+};
+
+/**
+ * Goes to the previous matching result, highlights it, and speaks it.
+ */
+cvox.ChromeVoxSearch.prev = function() {
+  if (cvox.ChromeVoxSearch.matchNodes &&
+      (cvox.ChromeVoxSearch.matchNodes.length > 0)) {
+    cvox.ChromeVoxSearch.matchNodesIndex--;
+    if (cvox.ChromeVoxSearch.matchNodesIndex > -1) {
+      var searchStr = cvox.ChromeVoxSearch.txtNode.textContent;
+      var targetNode = cvox.ChromeVoxSearch.matchNodes[
+          cvox.ChromeVoxSearch.matchNodesIndex];
+      var startIndex = 0;
+      if (cvox.ChromeVoxSearch.caseSensitive) {
+        startIndex = targetNode.textContent.indexOf(searchStr);
+      } else {
+        startIndex = targetNode.textContent.toLowerCase().indexOf(
+            searchStr.toLowerCase());
+      }
+      cvox.SelectionUtil.selectText(targetNode, startIndex,
+          startIndex + searchStr.length);
+      cvox.ChromeVox.traverseContent.moveNext('sentence');
+      var sel = window.getSelection();
+      var range = sel.getRangeAt(0);
+      range.setStart(targetNode, startIndex);
+      sel.removeAllRanges();
+      sel.addRange(range);
+      cvox.SelectionUtil.scrollToSelection(sel);
+      cvox.ChromeVox.tts.speak(window.getSelection() + '', 0, null);
+    } else {
+      cvox.ChromeVox.earcons.playEarcon(cvox.AbstractEarcons.WRAP);
+      cvox.ChromeVoxSearch.matchNodesIndex =
+          cvox.ChromeVoxSearch.matchNodes.length;
+      cvox.ChromeVoxSearch.prev();
+    }
+  }
+};