remoting/webapp/host_screen.js

   1 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 /**
   6  * @fileoverview
   7  * Functions related to the 'host screen' for Chromoting.
   8  */
   9
  10 'use strict';
  11
  12 /** @suppress {duplicate} */
  13 var remoting = remoting || {};
  14
  15 /**
  16  * @type {boolean} Whether or not the last share was cancelled by the user.
  17  *     This controls what screen is shown when the host signals completion.
  18  * @private
  19  */
  20 var lastShareWasCancelled_ = false;
  21
  22 /**
  23  * Start a host session. This is the main entry point for the host screen,
  24  * called directly from the onclick action of a button on the home screen.
  25  * It first verifies that the native host components are installed and asks
  26  * to install them if necessary.
  27  */
  28 remoting.tryShare = function() {
  29   /** @type {remoting.It2MeHostFacade} */
  30   var hostFacade = new remoting.It2MeHostFacade();
  31
  32   /** @type {remoting.HostInstallDialog} */
  33   var hostInstallDialog = null;
  34
  35   var tryInitializeFacade = function() {
  36     hostFacade.initialize(onFacadeInitialized, onFacadeInitializationFailed);
  37   }
  38
  39   var onFacadeInitialized = function () {
  40     // Host already installed.
  41     remoting.startHostUsingFacade_(hostFacade);
  42   };
  43
  44   var onFacadeInitializationFailed = function() {
  45     // If we failed to initialize the dispatcher then prompt the user to install
  46     // the host manually.
  47     var hasHostDialog = (hostInstallDialog != null);  /** jscompile hack */
  48     if (!hasHostDialog) {
  49       hostInstallDialog = new remoting.HostInstallDialog();
  50       hostInstallDialog.show(tryInitializeFacade, onInstallError);
  51     } else {
  52       hostInstallDialog.tryAgain();
  53     }
  54   };
  55
  56   /** @param {remoting.Error} error */
  57   var onInstallError = function(error) {
  58     if (error == remoting.Error.CANCELLED) {
  59       remoting.setMode(remoting.AppMode.HOME);
  60     } else {
  61       showShareError_(error);
  62     }
  63   }
  64
  65   tryInitializeFacade();
  66 };
  67
  68 /**
  69  * @param {remoting.It2MeHostFacade} hostFacade An initialized It2MeHostFacade.
  70  */
  71 remoting.startHostUsingFacade_ = function(hostFacade) {
  72   console.log('Attempting to share...');
  73   remoting.identity.callWithToken(
  74       remoting.tryShareWithToken_.bind(null, hostFacade),
  75       remoting.showErrorMessage);
  76 }
  77
  78 /**
  79  * @param {remoting.It2MeHostFacade} hostFacade An initialized
  80  *     It2MeHostFacade.
  81  * @param {string} token The OAuth access token.
  82  * @private
  83  */
  84 remoting.tryShareWithToken_ = function(hostFacade, token) {
  85   lastShareWasCancelled_ = false;
  86   onNatTraversalPolicyChanged_(true);  // Hide warning by default.
  87   remoting.setMode(remoting.AppMode.HOST_WAITING_FOR_CODE);
  88   document.getElementById('cancel-share-button').disabled = false;
  89   disableTimeoutCountdown_();
  90
  91   remoting.hostSession = new remoting.HostSession();
  92   var email = /** @type {string} */remoting.identity.getCachedEmail();
  93   remoting.hostSession.connect(
  94       hostFacade, email, token, onHostStateChanged_,
  95       onNatTraversalPolicyChanged_, logDebugInfo_, it2meConnectFailed_);
  96 };
  97
  98 /**
  99  * Callback for the host plugin to notify the web app of state changes.
 100  * @param {remoting.HostSession.State} state The new state of the plugin.
 101  * @return {void} Nothing.
 102  * @private
 103  */
 104 function onHostStateChanged_(state) {
 105   if (state == remoting.HostSession.State.STARTING) {
 106     // Nothing to do here.
 107     console.log('Host state: STARTING');
 108
 109   } else if (state == remoting.HostSession.State.REQUESTED_ACCESS_CODE) {
 110     // Nothing to do here.
 111     console.log('Host state: REQUESTED_ACCESS_CODE');
 112
 113   } else if (state == remoting.HostSession.State.RECEIVED_ACCESS_CODE) {
 114     console.log('Host state: RECEIVED_ACCESS_CODE');
 115     var accessCode = remoting.hostSession.getAccessCode();
 116     var accessCodeDisplay = document.getElementById('access-code-display');
 117     accessCodeDisplay.innerText = '';
 118     // Display the access code in groups of four digits for readability.
 119     var kDigitsPerGroup = 4;
 120     for (var i = 0; i < accessCode.length; i += kDigitsPerGroup) {
 121       var nextFourDigits = document.createElement('span');
 122       nextFourDigits.className = 'access-code-digit-group';
 123       nextFourDigits.innerText = accessCode.substring(i, i + kDigitsPerGroup);
 124       accessCodeDisplay.appendChild(nextFourDigits);
 125     }
 126     accessCodeExpiresIn_ = remoting.hostSession.getAccessCodeLifetime();
 127     if (accessCodeExpiresIn_ > 0) {  // Check it hasn't expired.
 128       accessCodeTimerId_ = setInterval(decrementAccessCodeTimeout_, 1000);
 129       timerRunning_ = true;
 130       updateAccessCodeTimeoutElement_();
 131       updateTimeoutStyles_();
 132       remoting.setMode(remoting.AppMode.HOST_WAITING_FOR_CONNECTION);
 133     } else {
 134       // This can only happen if the cloud tells us that the code lifetime is
 135       // <= 0s, which shouldn't happen so we don't care how clean this UX is.
 136       console.error('Access code already invalid on receipt!');
 137       remoting.cancelShare();
 138     }
 139
 140   } else if (state == remoting.HostSession.State.CONNECTED) {
 141     console.log('Host state: CONNECTED');
 142     var element = document.getElementById('host-shared-message');
 143     var client = remoting.hostSession.getClient();
 144     l10n.localizeElement(element, client);
 145     remoting.setMode(remoting.AppMode.HOST_SHARED);
 146     disableTimeoutCountdown_();
 147
 148   } else if (state == remoting.HostSession.State.DISCONNECTING) {
 149     console.log('Host state: DISCONNECTING');
 150
 151   } else if (state == remoting.HostSession.State.DISCONNECTED) {
 152     console.log('Host state: DISCONNECTED');
 153     if (remoting.currentMode != remoting.AppMode.HOST_SHARE_FAILED) {
 154       // If an error is being displayed, then the plugin should not be able to
 155       // hide it by setting the state. Errors must be dismissed by the user
 156       // clicking OK, which puts the app into mode HOME.
 157       if (lastShareWasCancelled_) {
 158         remoting.setMode(remoting.AppMode.HOME);
 159       } else {
 160         remoting.setMode(remoting.AppMode.HOST_SHARE_FINISHED);
 161       }
 162     }
 163   } else if (state == remoting.HostSession.State.ERROR) {
 164     console.error('Host state: ERROR');
 165     showShareError_(remoting.Error.UNEXPECTED);
 166   } else if (state == remoting.HostSession.State.INVALID_DOMAIN_ERROR) {
 167     console.error('Host state: INVALID_DOMAIN_ERROR');
 168     showShareError_(remoting.Error.INVALID_HOST_DOMAIN);
 169   } else {
 170     console.error('Unknown state -> ' + state);
 171   }
 172 }
 173
 174 /**
 175  * This is the callback that the host plugin invokes to indicate that there
 176  * is additional debug log info to display.
 177  * @param {string} msg The message (which will not be localized) to be logged.
 178  * @private
 179  */
 180 function logDebugInfo_(msg) {
 181   console.log('plugin: ' + msg);
 182 }
 183
 184 /**
 185  * Show a host-side error message.
 186  *
 187  * @param {string} errorTag The error message to be localized and displayed.
 188  * @return {void} Nothing.
 189  * @private
 190  */
 191 function showShareError_(errorTag) {
 192   var errorDiv = document.getElementById('host-plugin-error');
 193   l10n.localizeElementFromTag(errorDiv, errorTag);
 194   console.error('Sharing error: ' + errorTag);
 195   remoting.setMode(remoting.AppMode.HOST_SHARE_FAILED);
 196 }
 197
 198 /**
 199  * Show a sharing error with error code UNEXPECTED .
 200  *
 201  * @return {void} Nothing.
 202  * @private
 203  */
 204 function it2meConnectFailed_() {
 205   // TODO (weitaosu): Instruct the user to install the native messaging host.
 206   // We probably want to add a new error code (with the corresponding error
 207   // message for sharing error.
 208   console.error('Cannot share desktop.');
 209   showShareError_(remoting.Error.UNEXPECTED);
 210 }
 211
 212 /**
 213  * Cancel an active or pending it2me share operation.
 214  *
 215  * @return {void} Nothing.
 216  */
 217 remoting.cancelShare = function() {
 218   document.getElementById('cancel-share-button').disabled = true;
 219   console.log('Canceling share...');
 220   remoting.lastShareWasCancelled = true;
 221   try {
 222     remoting.hostSession.disconnect();
 223   } catch (error) {
 224     // Hack to force JSCompiler type-safety.
 225     var errorTyped = /** @type {{description: string}} */ error;
 226     console.error('Error disconnecting: ' + errorTyped.description +
 227                   '. The host probably crashed.');
 228     // TODO(jamiewalch): Clean this up. We should have a class representing
 229     // the host plugin, like we do for the client, which should handle crash
 230     // reporting and it should use a more detailed error message than the
 231     // default 'generic' one. See crbug.com/94624
 232     showShareError_(remoting.Error.UNEXPECTED);
 233   }
 234   disableTimeoutCountdown_();
 235 };
 236
 237 /**
 238  * @type {boolean} Whether or not the access code timeout countdown is running.
 239  * @private
 240  */
 241 var timerRunning_ = false;
 242
 243 /**
 244  * @type {number} The id of the access code expiry countdown timer.
 245  * @private
 246  */
 247 var accessCodeTimerId_ = 0;
 248
 249 /**
 250  * @type {number} The number of seconds until the access code expires.
 251  * @private
 252  */
 253 var accessCodeExpiresIn_ = 0;
 254
 255 /**
 256  * The timer callback function
 257  * @return {void} Nothing.
 258  * @private
 259  */
 260 function decrementAccessCodeTimeout_() {
 261   --accessCodeExpiresIn_;
 262   updateAccessCodeTimeoutElement_();
 263 };
 264
 265 /**
 266  * Stop the access code timeout countdown if it is running.
 267  * @return {void} Nothing.
 268  * @private
 269  */
 270 function disableTimeoutCountdown_() {
 271   if (timerRunning_) {
 272     clearInterval(accessCodeTimerId_);
 273     timerRunning_ = false;
 274     updateTimeoutStyles_();
 275   }
 276 }
 277
 278 /**
 279  * Constants controlling the access code timer countdown display.
 280  * @private
 281  */
 282 var ACCESS_CODE_TIMER_DISPLAY_THRESHOLD_ = 30;
 283 var ACCESS_CODE_RED_THRESHOLD_ = 10;
 284
 285 /**
 286  * Show/hide or restyle various elements, depending on the remaining countdown
 287  * and timer state.
 288  *
 289  * @return {boolean} True if the timeout is in progress, false if it has
 290  * expired.
 291  * @private
 292  */
 293 function updateTimeoutStyles_() {
 294   if (timerRunning_) {
 295     if (accessCodeExpiresIn_ <= 0) {
 296       remoting.cancelShare();
 297       return false;
 298     }
 299     var accessCode = document.getElementById('access-code-display');
 300     if (accessCodeExpiresIn_ <= ACCESS_CODE_RED_THRESHOLD_) {
 301       accessCode.classList.add('expiring');
 302     } else {
 303       accessCode.classList.remove('expiring');
 304     }
 305   }
 306   document.getElementById('access-code-countdown').hidden =
 307       (accessCodeExpiresIn_ > ACCESS_CODE_TIMER_DISPLAY_THRESHOLD_) ||
 308       !timerRunning_;
 309   return true;
 310 }
 311
 312 /**
 313  * Update the text and appearance of the access code timeout element to
 314  * reflect the time remaining.
 315  * @return {void} Nothing.
 316  * @private
 317  */
 318 function updateAccessCodeTimeoutElement_() {
 319   var pad = (accessCodeExpiresIn_ < 10) ? '0:0' : '0:';
 320   l10n.localizeElement(document.getElementById('seconds-remaining'),
 321                        pad + accessCodeExpiresIn_);
 322   if (!updateTimeoutStyles_()) {
 323     disableTimeoutCountdown_();
 324   }
 325 }
 326
 327 /**
 328  * Callback to show or hide the NAT traversal warning when the policy changes.
 329  * @param {boolean} enabled True if NAT traversal is enabled.
 330  * @return {void} Nothing.
 331  * @private
 332  */
 333 function onNatTraversalPolicyChanged_(enabled) {
 334   var natBox = document.getElementById('nat-box');
 335   if (enabled) {
 336     natBox.classList.add('traversal-enabled');
 337   } else {
 338     natBox.classList.remove('traversal-enabled');
 339   }
 340 }