michael@0: /* This Source Code Form is subject to the terms of the Mozilla Public
michael@0:  * License, v. 2.0. If a copy of the MPL was not distributed with this file,
michael@0:  * You can obtain one at http://mozilla.org/MPL/2.0/. */
michael@0: 
michael@0: 'use strict';
michael@0: 
michael@0: const Cu = Components.utils;
michael@0: const Cc = Components.classes;
michael@0: const Ci = Components.interfaces;
michael@0: 
michael@0: Cu.import("resource://gre/modules/XPCOMUtils.jsm");
michael@0: XPCOMUtils.defineLazyModuleGetter(this, 'Services',
michael@0:   'resource://gre/modules/Services.jsm');
michael@0: XPCOMUtils.defineLazyModuleGetter(this, 'Rect',
michael@0:   'resource://gre/modules/Geometry.jsm');
michael@0: XPCOMUtils.defineLazyModuleGetter(this, 'Roles',
michael@0:   'resource://gre/modules/accessibility/Constants.jsm');
michael@0: XPCOMUtils.defineLazyModuleGetter(this, 'Events',
michael@0:   'resource://gre/modules/accessibility/Constants.jsm');
michael@0: XPCOMUtils.defineLazyModuleGetter(this, 'Relations',
michael@0:   'resource://gre/modules/accessibility/Constants.jsm');
michael@0: XPCOMUtils.defineLazyModuleGetter(this, 'States',
michael@0:   'resource://gre/modules/accessibility/Constants.jsm');
michael@0: 
michael@0: this.EXPORTED_SYMBOLS = ['Utils', 'Logger', 'PivotContext', 'PrefCache', 'SettingCache'];
michael@0: 
michael@0: this.Utils = {
michael@0:   _buildAppMap: {
michael@0:     '{3c2e2abc-06d4-11e1-ac3b-374f68613e61}': 'b2g',
michael@0:     '{ec8030f7-c20a-464f-9b0e-13a3a9e97384}': 'browser',
michael@0:     '{aa3c5121-dab2-40e2-81ca-7ea25febc110}': 'mobile/android',
michael@0:     '{a23983c0-fd0e-11dc-95ff-0800200c9a66}': 'mobile/xul'
michael@0:   },
michael@0: 
michael@0:   init: function Utils_init(aWindow) {
michael@0:     if (this._win)
michael@0:       // XXX: only supports attaching to one window now.
michael@0:       throw new Error('Only one top-level window could used with AccessFu');
michael@0: 
michael@0:     this._win = Cu.getWeakReference(aWindow);
michael@0:   },
michael@0: 
michael@0:   uninit: function Utils_uninit() {
michael@0:     if (!this._win) {
michael@0:       return;
michael@0:     }
michael@0:     delete this._win;
michael@0:   },
michael@0: 
michael@0:   get win() {
michael@0:     if (!this._win) {
michael@0:       return null;
michael@0:     }
michael@0:     return this._win.get();
michael@0:   },
michael@0: 
michael@0:   get AccRetrieval() {
michael@0:     if (!this._AccRetrieval) {
michael@0:       this._AccRetrieval = Cc['@mozilla.org/accessibleRetrieval;1'].
michael@0:         getService(Ci.nsIAccessibleRetrieval);
michael@0:     }
michael@0: 
michael@0:     return this._AccRetrieval;
michael@0:   },
michael@0: 
michael@0:   set MozBuildApp(value) {
michael@0:     this._buildApp = value;
michael@0:   },
michael@0: 
michael@0:   get MozBuildApp() {
michael@0:     if (!this._buildApp)
michael@0:       this._buildApp = this._buildAppMap[Services.appinfo.ID];
michael@0:     return this._buildApp;
michael@0:   },
michael@0: 
michael@0:   get OS() {
michael@0:     if (!this._OS)
michael@0:       this._OS = Services.appinfo.OS;
michael@0:     return this._OS;
michael@0:   },
michael@0: 
michael@0:   get widgetToolkit() {
michael@0:     if (!this._widgetToolkit)
michael@0:       this._widgetToolkit = Services.appinfo.widgetToolkit;
michael@0:     return this._widgetToolkit;
michael@0:   },
michael@0: 
michael@0:   get ScriptName() {
michael@0:     if (!this._ScriptName)
michael@0:       this._ScriptName =
michael@0:         (Services.appinfo.processType == 2) ? 'AccessFuContent' : 'AccessFu';
michael@0:     return this._ScriptName;
michael@0:   },
michael@0: 
michael@0:   get AndroidSdkVersion() {
michael@0:     if (!this._AndroidSdkVersion) {
michael@0:       if (Services.appinfo.OS == 'Android') {
michael@0:         this._AndroidSdkVersion = Services.sysinfo.getPropertyAsInt32('version');
michael@0:       } else {
michael@0:         // Most useful in desktop debugging.
michael@0:         this._AndroidSdkVersion = 16;
michael@0:       }
michael@0:     }
michael@0:     return this._AndroidSdkVersion;
michael@0:   },
michael@0: 
michael@0:   set AndroidSdkVersion(value) {
michael@0:     // When we want to mimic another version.
michael@0:     this._AndroidSdkVersion = value;
michael@0:   },
michael@0: 
michael@0:   get BrowserApp() {
michael@0:     if (!this.win) {
michael@0:       return null;
michael@0:     }
michael@0:     switch (this.MozBuildApp) {
michael@0:       case 'mobile/android':
michael@0:         return this.win.BrowserApp;
michael@0:       case 'browser':
michael@0:         return this.win.gBrowser;
michael@0:       case 'b2g':
michael@0:         return this.win.shell;
michael@0:       default:
michael@0:         return null;
michael@0:     }
michael@0:   },
michael@0: 
michael@0:   get CurrentBrowser() {
michael@0:     if (!this.BrowserApp) {
michael@0:       return null;
michael@0:     }
michael@0:     if (this.MozBuildApp == 'b2g')
michael@0:       return this.BrowserApp.contentBrowser;
michael@0:     return this.BrowserApp.selectedBrowser;
michael@0:   },
michael@0: 
michael@0:   get CurrentContentDoc() {
michael@0:     let browser = this.CurrentBrowser;
michael@0:     return browser ? browser.contentDocument : null;
michael@0:   },
michael@0: 
michael@0:   get AllMessageManagers() {
michael@0:     let messageManagers = [];
michael@0: 
michael@0:     for (let i = 0; i < this.win.messageManager.childCount; i++)
michael@0:       messageManagers.push(this.win.messageManager.getChildAt(i));
michael@0: 
michael@0:     let document = this.CurrentContentDoc;
michael@0: 
michael@0:     if (document) {
michael@0:       let remoteframes = document.querySelectorAll('iframe');
michael@0: 
michael@0:       for (let i = 0; i < remoteframes.length; ++i) {
michael@0:         let mm = this.getMessageManager(remoteframes[i]);
michael@0:         if (mm) {
michael@0:           messageManagers.push(mm);
michael@0:         }
michael@0:       }
michael@0: 
michael@0:     }
michael@0: 
michael@0:     return messageManagers;
michael@0:   },
michael@0: 
michael@0:   get isContentProcess() {
michael@0:     delete this.isContentProcess;
michael@0:     this.isContentProcess =
michael@0:       Services.appinfo.processType == Services.appinfo.PROCESS_TYPE_CONTENT;
michael@0:     return this.isContentProcess;
michael@0:   },
michael@0: 
michael@0:   get stringBundle() {
michael@0:     delete this.stringBundle;
michael@0:     this.stringBundle = Services.strings.createBundle(
michael@0:       'chrome://global/locale/AccessFu.properties');
michael@0:     return this.stringBundle;
michael@0:   },
michael@0: 
michael@0:   getMessageManager: function getMessageManager(aBrowser) {
michael@0:     try {
michael@0:       return aBrowser.QueryInterface(Ci.nsIFrameLoaderOwner).
michael@0:          frameLoader.messageManager;
michael@0:     } catch (x) {
michael@0:       Logger.logException(x);
michael@0:       return null;
michael@0:     }
michael@0:   },
michael@0: 
michael@0:   getViewport: function getViewport(aWindow) {
michael@0:     switch (this.MozBuildApp) {
michael@0:       case 'mobile/android':
michael@0:         return aWindow.BrowserApp.selectedTab.getViewport();
michael@0:       default:
michael@0:         return null;
michael@0:     }
michael@0:   },
michael@0: 
michael@0:   getState: function getState(aAccessibleOrEvent) {
michael@0:     if (aAccessibleOrEvent instanceof Ci.nsIAccessibleStateChangeEvent) {
michael@0:       return new State(
michael@0:         aAccessibleOrEvent.isExtraState ? 0 : aAccessibleOrEvent.state,
michael@0:         aAccessibleOrEvent.isExtraState ? aAccessibleOrEvent.state : 0);
michael@0:     } else {
michael@0:       let state = {};
michael@0:       let extState = {};
michael@0:       aAccessibleOrEvent.getState(state, extState);
michael@0:       return new State(state.value, extState.value);
michael@0:     }
michael@0:   },
michael@0: 
michael@0:   getAttributes: function getAttributes(aAccessible) {
michael@0:     let attributes = {};
michael@0: 
michael@0:     if (aAccessible && aAccessible.attributes) {
michael@0:       let attributesEnum = aAccessible.attributes.enumerate();
michael@0: 
michael@0:       // Populate |attributes| object with |aAccessible|'s attribute key-value
michael@0:       // pairs.
michael@0:       while (attributesEnum.hasMoreElements()) {
michael@0:         let attribute = attributesEnum.getNext().QueryInterface(
michael@0:           Ci.nsIPropertyElement);
michael@0:         attributes[attribute.key] = attribute.value;
michael@0:       }
michael@0:     }
michael@0: 
michael@0:     return attributes;
michael@0:   },
michael@0: 
michael@0:   getVirtualCursor: function getVirtualCursor(aDocument) {
michael@0:     let doc = (aDocument instanceof Ci.nsIAccessible) ? aDocument :
michael@0:       this.AccRetrieval.getAccessibleFor(aDocument);
michael@0: 
michael@0:     return doc.QueryInterface(Ci.nsIAccessibleDocument).virtualCursor;
michael@0:   },
michael@0: 
michael@0:   getBounds: function getBounds(aAccessible) {
michael@0:       let objX = {}, objY = {}, objW = {}, objH = {};
michael@0:       aAccessible.getBounds(objX, objY, objW, objH);
michael@0:       return new Rect(objX.value, objY.value, objW.value, objH.value);
michael@0:   },
michael@0: 
michael@0:   getTextBounds: function getTextBounds(aAccessible, aStart, aEnd) {
michael@0:       let accText = aAccessible.QueryInterface(Ci.nsIAccessibleText);
michael@0:       let objX = {}, objY = {}, objW = {}, objH = {};
michael@0:       accText.getRangeExtents(aStart, aEnd, objX, objY, objW, objH,
michael@0:                               Ci.nsIAccessibleCoordinateType.COORDTYPE_SCREEN_RELATIVE);
michael@0:       return new Rect(objX.value, objY.value, objW.value, objH.value);
michael@0:   },
michael@0: 
michael@0:   /**
michael@0:    * Get current display DPI.
michael@0:    */
michael@0:   get dpi() {
michael@0:     delete this.dpi;
michael@0:     this.dpi = this.win.QueryInterface(Ci.nsIInterfaceRequestor).getInterface(
michael@0:       Ci.nsIDOMWindowUtils).displayDPI;
michael@0:     return this.dpi;
michael@0:   },
michael@0: 
michael@0:   isInSubtree: function isInSubtree(aAccessible, aSubTreeRoot) {
michael@0:     let acc = aAccessible;
michael@0:     while (acc) {
michael@0:       if (acc == aSubTreeRoot) {
michael@0:         return true;
michael@0:       }
michael@0: 
michael@0:       try {
michael@0:         acc = acc.parent;
michael@0:       } catch (x) {
michael@0:         Logger.debug('Failed to get parent:', x);
michael@0:         acc = null;
michael@0:       }
michael@0:     }
michael@0: 
michael@0:     return false;
michael@0:   },
michael@0: 
michael@0:   inHiddenSubtree: function inHiddenSubtree(aAccessible) {
michael@0:     for (let acc=aAccessible; acc; acc=acc.parent) {
michael@0:       let hidden = Utils.getAttributes(acc).hidden;
michael@0:       if (hidden && JSON.parse(hidden)) {
michael@0:         return true;
michael@0:       }
michael@0:     }
michael@0:     return false;
michael@0:   },
michael@0: 
michael@0:   isAliveAndVisible: function isAliveAndVisible(aAccessible, aIsOnScreen) {
michael@0:     if (!aAccessible) {
michael@0:       return false;
michael@0:     }
michael@0: 
michael@0:     try {
michael@0:       let state = this.getState(aAccessible);
michael@0:       if (state.contains(States.DEFUNCT) || state.contains(States.INVISIBLE) ||
michael@0:           (aIsOnScreen && state.contains(States.OFFSCREEN)) ||
michael@0:           Utils.inHiddenSubtree(aAccessible)) {
michael@0:         return false;
michael@0:       }
michael@0:     } catch (x) {
michael@0:       return false;
michael@0:     }
michael@0: 
michael@0:     return true;
michael@0:   },
michael@0: 
michael@0:   matchAttributeValue: function matchAttributeValue(aAttributeValue, values) {
michael@0:     let attrSet = new Set(aAttributeValue.split(' '));
michael@0:     for (let value of values) {
michael@0:       if (attrSet.has(value)) {
michael@0:         return value;
michael@0:       }
michael@0:     }
michael@0:   },
michael@0: 
michael@0:   getLandmarkName: function getLandmarkName(aAccessible) {
michael@0:     const landmarks = [
michael@0:       'banner',
michael@0:       'complementary',
michael@0:       'contentinfo',
michael@0:       'main',
michael@0:       'navigation',
michael@0:       'search'
michael@0:     ];
michael@0:     let roles = this.getAttributes(aAccessible)['xml-roles'];
michael@0:     if (!roles) {
michael@0:       return;
michael@0:     }
michael@0: 
michael@0:     // Looking up a role that would match a landmark.
michael@0:     return this.matchAttributeValue(roles, landmarks);
michael@0:   },
michael@0: 
michael@0:   getEmbeddedControl: function getEmbeddedControl(aLabel) {
michael@0:     if (aLabel) {
michael@0:       let relation = aLabel.getRelationByType(Relations.LABEL_FOR);
michael@0:       for (let i = 0; i < relation.targetsCount; i++) {
michael@0:         let target = relation.getTarget(i);
michael@0:         if (target.parent === aLabel) {
michael@0:           return target;
michael@0:         }
michael@0:       }
michael@0:     }
michael@0: 
michael@0:     return null;
michael@0:   }
michael@0: };
michael@0: 
michael@0: /**
michael@0:  * State object used internally to process accessible's states.
michael@0:  * @param {Number} aBase     Base state.
michael@0:  * @param {Number} aExtended Extended state.
michael@0:  */
michael@0: function State(aBase, aExtended) {
michael@0:   this.base = aBase;
michael@0:   this.extended = aExtended;
michael@0: }
michael@0: 
michael@0: State.prototype = {
michael@0:   contains: function State_contains(other) {
michael@0:     return !!(this.base & other.base || this.extended & other.extended);
michael@0:   },
michael@0:   toString: function State_toString() {
michael@0:     let stateStrings = Utils.AccRetrieval.
michael@0:       getStringStates(this.base, this.extended);
michael@0:     let statesArray = new Array(stateStrings.length);
michael@0:     for (let i = 0; i < statesArray.length; i++) {
michael@0:       statesArray[i] = stateStrings.item(i);
michael@0:     }
michael@0:     return '[' + statesArray.join(', ') + ']';
michael@0:   }
michael@0: };
michael@0: 
michael@0: this.Logger = {
michael@0:   DEBUG: 0,
michael@0:   INFO: 1,
michael@0:   WARNING: 2,
michael@0:   ERROR: 3,
michael@0:   _LEVEL_NAMES: ['DEBUG', 'INFO', 'WARNING', 'ERROR'],
michael@0: 
michael@0:   logLevel: 1, // INFO;
michael@0: 
michael@0:   test: false,
michael@0: 
michael@0:   log: function log(aLogLevel) {
michael@0:     if (aLogLevel < this.logLevel)
michael@0:       return;
michael@0: 
michael@0:     let args = Array.prototype.slice.call(arguments, 1);
michael@0:     let message = (typeof(args[0]) === 'function' ? args[0]() : args).join(' ');
michael@0:     message = '[' + Utils.ScriptName + '] ' + this._LEVEL_NAMES[aLogLevel] +
michael@0:       ' ' + message + '\n';
michael@0:     dump(message);
michael@0:     // Note: used for testing purposes. If |this.test| is true, also log to
michael@0:     // the console service.
michael@0:     if (this.test) {
michael@0:       try {
michael@0:         Services.console.logStringMessage(message);
michael@0:       } catch (ex) {
michael@0:         // There was an exception logging to the console service.
michael@0:       }
michael@0:     }
michael@0:   },
michael@0: 
michael@0:   info: function info() {
michael@0:     this.log.apply(
michael@0:       this, [this.INFO].concat(Array.prototype.slice.call(arguments)));
michael@0:   },
michael@0: 
michael@0:   debug: function debug() {
michael@0:     this.log.apply(
michael@0:       this, [this.DEBUG].concat(Array.prototype.slice.call(arguments)));
michael@0:   },
michael@0: 
michael@0:   warning: function warning() {
michael@0:     this.log.apply(
michael@0:       this, [this.WARNING].concat(Array.prototype.slice.call(arguments)));
michael@0:   },
michael@0: 
michael@0:   error: function error() {
michael@0:     this.log.apply(
michael@0:       this, [this.ERROR].concat(Array.prototype.slice.call(arguments)));
michael@0:   },
michael@0: 
michael@0:   logException: function logException(
michael@0:     aException, aErrorMessage = 'An exception has occured') {
michael@0:     try {
michael@0:       let stackMessage = '';
michael@0:       if (aException.stack) {
michael@0:         stackMessage = '  ' + aException.stack.replace(/\n/g, '\n  ');
michael@0:       } else if (aException.location) {
michael@0:         let frame = aException.location;
michael@0:         let stackLines = [];
michael@0:         while (frame && frame.lineNumber) {
michael@0:           stackLines.push(
michael@0:             '  ' + frame.name + '@' + frame.filename + ':' + frame.lineNumber);
michael@0:           frame = frame.caller;
michael@0:         }
michael@0:         stackMessage = stackLines.join('\n');
michael@0:       } else {
michael@0:         stackMessage = '(' + aException.fileName + ':' + aException.lineNumber + ')';
michael@0:       }
michael@0:       this.error(aErrorMessage + ':\n ' +
michael@0:                  aException.message + '\n' +
michael@0:                  stackMessage);
michael@0:     } catch (x) {
michael@0:       this.error(x);
michael@0:     }
michael@0:   },
michael@0: 
michael@0:   accessibleToString: function accessibleToString(aAccessible) {
michael@0:     let str = '[ defunct ]';
michael@0:     try {
michael@0:       str = '[ ' + Utils.AccRetrieval.getStringRole(aAccessible.role) +
michael@0:         ' | ' + aAccessible.name + ' ]';
michael@0:     } catch (x) {
michael@0:     }
michael@0: 
michael@0:     return str;
michael@0:   },
michael@0: 
michael@0:   eventToString: function eventToString(aEvent) {
michael@0:     let str = Utils.AccRetrieval.getStringEventType(aEvent.eventType);
michael@0:     if (aEvent.eventType == Events.STATE_CHANGE) {
michael@0:       let event = aEvent.QueryInterface(Ci.nsIAccessibleStateChangeEvent);
michael@0:       let stateStrings = event.isExtraState ?
michael@0:         Utils.AccRetrieval.getStringStates(0, event.state) :
michael@0:         Utils.AccRetrieval.getStringStates(event.state, 0);
michael@0:       str += ' (' + stateStrings.item(0) + ')';
michael@0:     }
michael@0: 
michael@0:     if (aEvent.eventType == Events.VIRTUALCURSOR_CHANGED) {
michael@0:       let event = aEvent.QueryInterface(
michael@0:         Ci.nsIAccessibleVirtualCursorChangeEvent);
michael@0:       let pivot = aEvent.accessible.QueryInterface(
michael@0:         Ci.nsIAccessibleDocument).virtualCursor;
michael@0:       str += ' (' + this.accessibleToString(event.oldAccessible) + ' -> ' +
michael@0: 	this.accessibleToString(pivot.position) + ')';
michael@0:     }
michael@0: 
michael@0:     return str;
michael@0:   },
michael@0: 
michael@0:   statesToString: function statesToString(aAccessible) {
michael@0:     return Utils.getState(aAccessible).toString();
michael@0:   },
michael@0: 
michael@0:   dumpTree: function dumpTree(aLogLevel, aRootAccessible) {
michael@0:     if (aLogLevel < this.logLevel)
michael@0:       return;
michael@0: 
michael@0:     this._dumpTreeInternal(aLogLevel, aRootAccessible, 0);
michael@0:   },
michael@0: 
michael@0:   _dumpTreeInternal: function _dumpTreeInternal(aLogLevel, aAccessible, aIndent) {
michael@0:     let indentStr = '';
michael@0:     for (var i=0; i < aIndent; i++)
michael@0:       indentStr += ' ';
michael@0:     this.log(aLogLevel, indentStr,
michael@0:              this.accessibleToString(aAccessible),
michael@0:              '(' + this.statesToString(aAccessible) + ')');
michael@0:     for (var i=0; i < aAccessible.childCount; i++)
michael@0:       this._dumpTreeInternal(aLogLevel, aAccessible.getChildAt(i), aIndent + 1);
michael@0:     }
michael@0: };
michael@0: 
michael@0: /**
michael@0:  * PivotContext: An object that generates and caches context information
michael@0:  * for a given accessible and its relationship with another accessible.
michael@0:  *
michael@0:  * If the given accessible is a label for a nested control, then this
michael@0:  * context will represent the nested control instead of the label.
michael@0:  * With the exception of bounds calculation, which will use the containing
michael@0:  * label. In this case the |accessible| field would be the embedded control,
michael@0:  * and the |accessibleForBounds| field would be the label.
michael@0:  */
michael@0: this.PivotContext = function PivotContext(aAccessible, aOldAccessible,
michael@0:   aStartOffset, aEndOffset, aIgnoreAncestry = false,
michael@0:   aIncludeInvisible = false) {
michael@0:   this._accessible = aAccessible;
michael@0:   this._nestedControl = Utils.getEmbeddedControl(aAccessible);
michael@0:   this._oldAccessible =
michael@0:     this._isDefunct(aOldAccessible) ? null : aOldAccessible;
michael@0:   this.startOffset = aStartOffset;
michael@0:   this.endOffset = aEndOffset;
michael@0:   this._ignoreAncestry = aIgnoreAncestry;
michael@0:   this._includeInvisible = aIncludeInvisible;
michael@0: }
michael@0: 
michael@0: PivotContext.prototype = {
michael@0:   get accessible() {
michael@0:     // If the current pivot accessible has a nested control,
michael@0:     // make this context use it publicly.
michael@0:     return this._nestedControl || this._accessible;
michael@0:   },
michael@0: 
michael@0:   get oldAccessible() {
michael@0:     return this._oldAccessible;
michael@0:   },
michael@0: 
michael@0:   get isNestedControl() {
michael@0:     return !!this._nestedControl;
michael@0:   },
michael@0: 
michael@0:   get accessibleForBounds() {
michael@0:     return this._accessible;
michael@0:   },
michael@0: 
michael@0:   get textAndAdjustedOffsets() {
michael@0:     if (this.startOffset === -1 && this.endOffset === -1) {
michael@0:       return null;
michael@0:     }
michael@0: 
michael@0:     if (!this._textAndAdjustedOffsets) {
michael@0:       let result = {startOffset: this.startOffset,
michael@0:                     endOffset: this.endOffset,
michael@0:                     text: this._accessible.QueryInterface(Ci.nsIAccessibleText).
michael@0:                           getText(0, Ci.nsIAccessibleText.TEXT_OFFSET_END_OF_TEXT)};
michael@0:       let hypertextAcc = this._accessible.QueryInterface(Ci.nsIAccessibleHyperText);
michael@0: 
michael@0:       // Iterate through the links in backwards order so text replacements don't
michael@0:       // affect the offsets of links yet to be processed.
michael@0:       for (let i = hypertextAcc.linkCount - 1; i >= 0; i--) {
michael@0:         let link = hypertextAcc.getLinkAt(i);
michael@0:         let linkText = '';
michael@0:         if (link instanceof Ci.nsIAccessibleText) {
michael@0:           linkText = link.QueryInterface(Ci.nsIAccessibleText).
michael@0:                           getText(0, Ci.nsIAccessibleText.TEXT_OFFSET_END_OF_TEXT);
michael@0:         }
michael@0: 
michael@0:         let start = link.startIndex;
michael@0:         let end = link.endIndex;
michael@0:         for (let offset of ['startOffset', 'endOffset']) {
michael@0:           if (this[offset] >= end) {
michael@0:             result[offset] += linkText.length - (end - start);
michael@0:           }
michael@0:         }
michael@0:         result.text = result.text.substring(0, start) + linkText +
michael@0:                       result.text.substring(end);
michael@0:       }
michael@0: 
michael@0:       this._textAndAdjustedOffsets = result;
michael@0:     }
michael@0: 
michael@0:     return this._textAndAdjustedOffsets;
michael@0:   },
michael@0: 
michael@0:   /**
michael@0:    * Get a list of |aAccessible|'s ancestry up to the root.
michael@0:    * @param  {nsIAccessible} aAccessible.
michael@0:    * @return {Array} Ancestry list.
michael@0:    */
michael@0:   _getAncestry: function _getAncestry(aAccessible) {
michael@0:     let ancestry = [];
michael@0:     let parent = aAccessible;
michael@0:     try {
michael@0:       while (parent && (parent = parent.parent)) {
michael@0:        ancestry.push(parent);
michael@0:       }
michael@0:     } catch (x) {
michael@0:       // A defunct accessible will raise an exception geting parent.
michael@0:       Logger.debug('Failed to get parent:', x);
michael@0:     }
michael@0:     return ancestry.reverse();
michael@0:   },
michael@0: 
michael@0:   /**
michael@0:    * A list of the old accessible's ancestry.
michael@0:    */
michael@0:   get oldAncestry() {
michael@0:     if (!this._oldAncestry) {
michael@0:       if (!this._oldAccessible || this._ignoreAncestry) {
michael@0:         this._oldAncestry = [];
michael@0:       } else {
michael@0:         this._oldAncestry = this._getAncestry(this._oldAccessible);
michael@0:         this._oldAncestry.push(this._oldAccessible);
michael@0:       }
michael@0:     }
michael@0:     return this._oldAncestry;
michael@0:   },
michael@0: 
michael@0:   /**
michael@0:    * A list of the current accessible's ancestry.
michael@0:    */
michael@0:   get currentAncestry() {
michael@0:     if (!this._currentAncestry) {
michael@0:       this._currentAncestry = this._ignoreAncestry ? [] :
michael@0:         this._getAncestry(this.accessible);
michael@0:     }
michael@0:     return this._currentAncestry;
michael@0:   },
michael@0: 
michael@0:   /*
michael@0:    * This is a list of the accessible's ancestry up to the common ancestor
michael@0:    * of the accessible and the old accessible. It is useful for giving the
michael@0:    * user context as to where they are in the heirarchy.
michael@0:    */
michael@0:   get newAncestry() {
michael@0:     if (!this._newAncestry) {
michael@0:       this._newAncestry = this._ignoreAncestry ? [] : [currentAncestor for (
michael@0:         [index, currentAncestor] of Iterator(this.currentAncestry)) if (
michael@0:           currentAncestor !== this.oldAncestry[index])];
michael@0:     }
michael@0:     return this._newAncestry;
michael@0:   },
michael@0: 
michael@0:   /*
michael@0:    * Traverse the accessible's subtree in pre or post order.
michael@0:    * It only includes the accessible's visible chidren.
michael@0:    * Note: needSubtree is a function argument that can be used to determine
michael@0:    * whether aAccessible's subtree is required.
michael@0:    */
michael@0:   _traverse: function _traverse(aAccessible, aPreorder, aStop) {
michael@0:     if (aStop && aStop(aAccessible)) {
michael@0:       return;
michael@0:     }
michael@0:     let child = aAccessible.firstChild;
michael@0:     while (child) {
michael@0:       let include;
michael@0:       if (this._includeInvisible) {
michael@0:         include = true;
michael@0:       } else {
michael@0:         include = !(Utils.getState(child).contains(States.INVISIBLE));
michael@0:       }
michael@0:       if (include) {
michael@0:         if (aPreorder) {
michael@0:           yield child;
michael@0:           [yield node for (node of this._traverse(child, aPreorder, aStop))];
michael@0:         } else {
michael@0:           [yield node for (node of this._traverse(child, aPreorder, aStop))];
michael@0:           yield child;
michael@0:         }
michael@0:       }
michael@0:       child = child.nextSibling;
michael@0:     }
michael@0:   },
michael@0: 
michael@0:   /*
michael@0:    * A subtree generator function, used to generate a flattened
michael@0:    * list of the accessible's subtree in pre or post order.
michael@0:    * It only includes the accessible's visible chidren.
michael@0:    * @param {boolean} aPreorder A flag for traversal order. If true, traverse
michael@0:    * in preorder; if false, traverse in postorder.
michael@0:    * @param {function} aStop An optional function, indicating whether subtree
michael@0:    * traversal should stop.
michael@0:    */
michael@0:   subtreeGenerator: function subtreeGenerator(aPreorder, aStop) {
michael@0:     return this._traverse(this.accessible, aPreorder, aStop);
michael@0:   },
michael@0: 
michael@0:   getCellInfo: function getCellInfo(aAccessible) {
michael@0:     if (!this._cells) {
michael@0:       this._cells = new WeakMap();
michael@0:     }
michael@0: 
michael@0:     let domNode = aAccessible.DOMNode;
michael@0:     if (this._cells.has(domNode)) {
michael@0:       return this._cells.get(domNode);
michael@0:     }
michael@0: 
michael@0:     let cellInfo = {};
michael@0:     let getAccessibleCell = function getAccessibleCell(aAccessible) {
michael@0:       if (!aAccessible) {
michael@0:         return null;
michael@0:       }
michael@0:       if ([Roles.CELL, Roles.COLUMNHEADER, Roles.ROWHEADER].indexOf(
michael@0:         aAccessible.role) < 0) {
michael@0:           return null;
michael@0:       }
michael@0:       try {
michael@0:         return aAccessible.QueryInterface(Ci.nsIAccessibleTableCell);
michael@0:       } catch (x) {
michael@0:         Logger.logException(x);
michael@0:         return null;
michael@0:       }
michael@0:     };
michael@0:     let getHeaders = function getHeaders(aHeaderCells) {
michael@0:       let enumerator = aHeaderCells.enumerate();
michael@0:       while (enumerator.hasMoreElements()) {
michael@0:         yield enumerator.getNext().QueryInterface(Ci.nsIAccessible).name;
michael@0:       }
michael@0:     };
michael@0: 
michael@0:     cellInfo.current = getAccessibleCell(aAccessible);
michael@0: 
michael@0:     if (!cellInfo.current) {
michael@0:       Logger.warning(aAccessible,
michael@0:         'does not support nsIAccessibleTableCell interface.');
michael@0:       this._cells.set(domNode, null);
michael@0:       return null;
michael@0:     }
michael@0: 
michael@0:     let table = cellInfo.current.table;
michael@0:     if (table.isProbablyForLayout()) {
michael@0:       this._cells.set(domNode, null);
michael@0:       return null;
michael@0:     }
michael@0: 
michael@0:     cellInfo.previous = null;
michael@0:     let oldAncestry = this.oldAncestry.reverse();
michael@0:     let ancestor = oldAncestry.shift();
michael@0:     while (!cellInfo.previous && ancestor) {
michael@0:       let cell = getAccessibleCell(ancestor);
michael@0:       if (cell && cell.table === table) {
michael@0:         cellInfo.previous = cell;
michael@0:       }
michael@0:       ancestor = oldAncestry.shift();
michael@0:     }
michael@0: 
michael@0:     if (cellInfo.previous) {
michael@0:       cellInfo.rowChanged = cellInfo.current.rowIndex !==
michael@0:         cellInfo.previous.rowIndex;
michael@0:       cellInfo.columnChanged = cellInfo.current.columnIndex !==
michael@0:         cellInfo.previous.columnIndex;
michael@0:     } else {
michael@0:       cellInfo.rowChanged = true;
michael@0:       cellInfo.columnChanged = true;
michael@0:     }
michael@0: 
michael@0:     cellInfo.rowExtent = cellInfo.current.rowExtent;
michael@0:     cellInfo.columnExtent = cellInfo.current.columnExtent;
michael@0:     cellInfo.columnIndex = cellInfo.current.columnIndex;
michael@0:     cellInfo.rowIndex = cellInfo.current.rowIndex;
michael@0: 
michael@0:     cellInfo.columnHeaders = [];
michael@0:     if (cellInfo.columnChanged && cellInfo.current.role !==
michael@0:       Roles.COLUMNHEADER) {
michael@0:       cellInfo.columnHeaders = [headers for (headers of getHeaders(
michael@0:         cellInfo.current.columnHeaderCells))];
michael@0:     }
michael@0:     cellInfo.rowHeaders = [];
michael@0:     if (cellInfo.rowChanged && cellInfo.current.role === Roles.CELL) {
michael@0:       cellInfo.rowHeaders = [headers for (headers of getHeaders(
michael@0:         cellInfo.current.rowHeaderCells))];
michael@0:     }
michael@0: 
michael@0:     this._cells.set(domNode, cellInfo);
michael@0:     return cellInfo;
michael@0:   },
michael@0: 
michael@0:   get bounds() {
michael@0:     if (!this._bounds) {
michael@0:       this._bounds = Utils.getBounds(this.accessibleForBounds);
michael@0:     }
michael@0: 
michael@0:     return this._bounds.clone();
michael@0:   },
michael@0: 
michael@0:   _isDefunct: function _isDefunct(aAccessible) {
michael@0:     try {
michael@0:       return Utils.getState(aAccessible).contains(States.DEFUNCT);
michael@0:     } catch (x) {
michael@0:       return true;
michael@0:     }
michael@0:   }
michael@0: };
michael@0: 
michael@0: this.PrefCache = function PrefCache(aName, aCallback, aRunCallbackNow) {
michael@0:   this.name = aName;
michael@0:   this.callback = aCallback;
michael@0: 
michael@0:   let branch = Services.prefs;
michael@0:   this.value = this._getValue(branch);
michael@0: 
michael@0:   if (this.callback && aRunCallbackNow) {
michael@0:     try {
michael@0:       this.callback(this.name, this.value);
michael@0:     } catch (x) {
michael@0:       Logger.logException(x);
michael@0:     }
michael@0:   }
michael@0: 
michael@0:   branch.addObserver(aName, this, true);
michael@0: };
michael@0: 
michael@0: PrefCache.prototype = {
michael@0:   _getValue: function _getValue(aBranch) {
michael@0:     try {
michael@0:       if (!this.type) {
michael@0:         this.type = aBranch.getPrefType(this.name);
michael@0:       }
michael@0:       switch (this.type) {
michael@0:         case Ci.nsIPrefBranch.PREF_STRING:
michael@0:           return aBranch.getCharPref(this.name);
michael@0:         case Ci.nsIPrefBranch.PREF_INT:
michael@0:           return aBranch.getIntPref(this.name);
michael@0:         case Ci.nsIPrefBranch.PREF_BOOL:
michael@0:           return aBranch.getBoolPref(this.name);
michael@0:         default:
michael@0:           return null;
michael@0:       }
michael@0:     } catch (x) {
michael@0:       // Pref does not exist.
michael@0:       return null;
michael@0:     }
michael@0:   },
michael@0: 
michael@0:   observe: function observe(aSubject, aTopic, aData) {
michael@0:     this.value = this._getValue(aSubject.QueryInterface(Ci.nsIPrefBranch));
michael@0:     if (this.callback) {
michael@0:       try {
michael@0:         this.callback(this.name, this.value);
michael@0:       } catch (x) {
michael@0:         Logger.logException(x);
michael@0:       }
michael@0:     }
michael@0:   },
michael@0: 
michael@0:   QueryInterface : XPCOMUtils.generateQI([Ci.nsIObserver,
michael@0:                                           Ci.nsISupportsWeakReference])
michael@0: };
michael@0: 
michael@0: this.SettingCache = function SettingCache(aName, aCallback, aOptions = {}) {
michael@0:   this.value = aOptions.defaultValue;
michael@0:   let runCallback = () => {
michael@0:     if (aCallback) {
michael@0:       aCallback(aName, this.value);
michael@0:       if (aOptions.callbackOnce) {
michael@0:         runCallback = () => {};
michael@0:       }
michael@0:     }
michael@0:   };
michael@0: 
michael@0:   let settings = Utils.win.navigator.mozSettings;
michael@0:   if (!settings) {
michael@0:     if (aOptions.callbackNow) {
michael@0:       runCallback();
michael@0:     }
michael@0:     return;
michael@0:   }
michael@0: 
michael@0: 
michael@0:   let lock = settings.createLock();
michael@0:   let req = lock.get(aName);
michael@0: 
michael@0:   req.addEventListener('success', () => {
michael@0:     this.value = req.result[aName] == undefined ? aOptions.defaultValue : req.result[aName];
michael@0:     if (aOptions.callbackNow) {
michael@0:       runCallback();
michael@0:     }
michael@0:   });
michael@0: 
michael@0:   settings.addObserver(aName,
michael@0:                        (evt) => {
michael@0:                          this.value = evt.settingValue;
michael@0:                          runCallback();
michael@0:                        });
michael@0: };