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diff --git a/remoting/webapp/oauth2.js b/remoting/webapp/oauth2.js
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+// 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
+ * OAuth2 class that handles retrieval/storage of an OAuth2 token.
+ *
+ * Uses a content script to trampoline the OAuth redirect page back into the
+ * extension context.  This works around the lack of native support for
+ * chrome-extensions in OAuth2.
+ */
+
+'use strict';
+
+/** @suppress {duplicate} */
+var remoting = remoting || {};
+
+/** @type {remoting.OAuth2} */
+remoting.oauth2 = null;
+
+
+/** @constructor */
+remoting.OAuth2 = function() {
+};
+
+// Constants representing keys used for storing persistent state.
+/** @private */
+remoting.OAuth2.prototype.KEY_REFRESH_TOKEN_ = 'oauth2-refresh-token';
+/** @private */
+remoting.OAuth2.prototype.KEY_ACCESS_TOKEN_ = 'oauth2-access-token';
+/** @private */
+remoting.OAuth2.prototype.KEY_EMAIL_ = 'remoting-email';
+
+// Constants for parameters used in retrieving the OAuth2 credentials.
+/** @private */
+remoting.OAuth2.prototype.CLIENT_ID_ =
+      '440925447803-2pi3v45bff6tp1rde2f7q6lgbor3o5uj.' +
+      'apps.googleusercontent.com';
+/** @private */
+remoting.OAuth2.prototype.CLIENT_SECRET_ = 'W2ieEsG-R1gIA4MMurGrgMc_';
+/** @private */
+remoting.OAuth2.prototype.SCOPE_ =
+      'https://www.googleapis.com/auth/chromoting ' +
+      'https://www.googleapis.com/auth/googletalk ' +
+      'https://www.googleapis.com/auth/userinfo#email';
+/** @private */
+remoting.OAuth2.prototype.REDIRECT_URI_ =
+      'https://talkgadget.google.com/talkgadget/blank';
+/** @private */
+remoting.OAuth2.prototype.OAUTH2_TOKEN_ENDPOINT_ =
+    'https://accounts.google.com/o/oauth2/token';
+
+/** @return {boolean} True if the app is already authenticated. */
+remoting.OAuth2.prototype.isAuthenticated = function() {
+  if (this.getRefreshToken()) {
+    return true;
+  }
+  return false;
+};
+
+/**
+ * Removes all storage, and effectively unauthenticates the user.
+ *
+ * @return {void} Nothing.
+ */
+remoting.OAuth2.prototype.clear = function() {
+  window.localStorage.removeItem(this.KEY_REFRESH_TOKEN_);
+  window.localStorage.removeItem(this.KEY_EMAIL_);
+  this.clearAccessToken();
+};
+
+/**
+ * @param {string} token The new refresh token.
+ * @return {void} Nothing.
+ */
+remoting.OAuth2.prototype.setRefreshToken = function(token) {
+  window.localStorage.setItem(this.KEY_REFRESH_TOKEN_, escape(token));
+  this.clearAccessToken();
+};
+
+/** @return {?string} The refresh token, if authenticated, or NULL. */
+remoting.OAuth2.prototype.getRefreshToken = function() {
+  var value = window.localStorage.getItem(this.KEY_REFRESH_TOKEN_);
+  if (typeof value == 'string') {
+    return unescape(value);
+  }
+  return null;
+};
+
+/**
+ * @param {string} token The new access token.
+ * @param {number} expiration Expiration time in milliseconds since epoch.
+ * @return {void} Nothing.
+ */
+remoting.OAuth2.prototype.setAccessToken = function(token, expiration) {
+  var access_token = {'token': token, 'expiration': expiration};
+  window.localStorage.setItem(this.KEY_ACCESS_TOKEN_,
+                              JSON.stringify(access_token));
+};
+
+/**
+ * Returns the current access token, setting it to a invalid value if none
+ * existed before.
+ *
+ * @private
+ * @return {{token: string, expiration: number}} The current access token, or
+ * an invalid token if not authenticated.
+ */
+remoting.OAuth2.prototype.getAccessTokenInternal_ = function() {
+  if (!window.localStorage.getItem(this.KEY_ACCESS_TOKEN_)) {
+    // Always be able to return structured data.
+    this.setAccessToken('', 0);
+  }
+  var accessToken = window.localStorage.getItem(this.KEY_ACCESS_TOKEN_);
+  if (typeof accessToken == 'string') {
+    var result = JSON.parse(accessToken);
+    if ('token' in result && 'expiration' in result) {
+      return /** @type {{token: string, expiration: number}} */ result;
+    }
+  }
+  console.log('Invalid access token stored.');
+  return {'token': '', 'expiration': 0};
+};
+
+/**
+ * Returns true if the access token is expired, or otherwise invalid.
+ *
+ * Will throw if !isAuthenticated().
+ *
+ * @return {boolean} True if a new access token is needed.
+ */
+remoting.OAuth2.prototype.needsNewAccessToken = function() {
+  if (!this.isAuthenticated()) {
+    throw 'Not Authenticated.';
+  }
+  var access_token = this.getAccessTokenInternal_();
+  if (!access_token['token']) {
+    return true;
+  }
+  if (Date.now() > access_token['expiration']) {
+    return true;
+  }
+  return false;
+};
+
+/**
+ * Returns the current access token.
+ *
+ * Will throw if !isAuthenticated() or needsNewAccessToken().
+ *
+ * @return {string} The access token.
+ */
+remoting.OAuth2.prototype.getAccessToken = function() {
+  if (this.needsNewAccessToken()) {
+    throw 'Access Token expired.';
+  }
+  return this.getAccessTokenInternal_()['token'];
+};
+
+/** @return {void} Nothing. */
+remoting.OAuth2.prototype.clearAccessToken = function() {
+  window.localStorage.removeItem(this.KEY_ACCESS_TOKEN_);
+};
+
+/**
+ * Update state based on token response from the OAuth2 /token endpoint.
+ *
+ * @private
+ * @param {XMLHttpRequest} xhr The XHR object for this request.
+ * @return {void} Nothing.
+ */
+remoting.OAuth2.prototype.processTokenResponse_ = function(xhr) {
+  if (xhr.status == 200) {
+    var tokens = JSON.parse(xhr.responseText);
+    if ('refresh_token' in tokens) {
+      this.setRefreshToken(tokens['refresh_token']);
+    }
+
+    // Offset by 120 seconds so that we can guarantee that the token
+    // we return will be valid for at least 2 minutes.
+    // If the access token is to be useful, this object must make some
+    // guarantee as to how long the token will be valid for.
+    // The choice of 2 minutes is arbitrary, but that length of time
+    // is part of the contract satisfied by callWithToken().
+    // Offset by a further 30 seconds to account for RTT issues.
+    this.setAccessToken(tokens['access_token'],
+        (tokens['expires_in'] - (120 + 30)) * 1000 + Date.now());
+  } else {
+    console.log('Failed to get tokens. Status: ' + xhr.status +
+                ' response: ' + xhr.responseText);
+  }
+};
+
+/**
+ * Asynchronously retrieves a new access token from the server.
+ *
+ * Will throw if !isAuthenticated().
+ *
+ * @param {function(XMLHttpRequest): void} onDone Callback to invoke on
+ *     completion.
+ * @return {void} Nothing.
+ */
+remoting.OAuth2.prototype.refreshAccessToken = function(onDone) {
+  if (!this.isAuthenticated()) {
+    throw 'Not Authenticated.';
+  }
+
+  var parameters = {
+    'client_id': this.CLIENT_ID_,
+    'client_secret': this.CLIENT_SECRET_,
+    'refresh_token': this.getRefreshToken(),
+    'grant_type': 'refresh_token'
+  };
+
+  /** @type {remoting.OAuth2} */
+  var that = this;
+  /** @param {XMLHttpRequest} xhr The XHR reply. */
+  var processTokenResponse = function(xhr) {
+    that.processTokenResponse_(xhr);
+    onDone(xhr);
+  };
+  remoting.xhr.post(this.OAUTH2_TOKEN_ENDPOINT_,
+                    processTokenResponse,
+                    parameters);
+};
+
+/**
+ * Redirect page to get a new OAuth2 Refresh Token.
+ *
+ * @return {void} Nothing.
+ */
+remoting.OAuth2.prototype.doAuthRedirect = function() {
+  var GET_CODE_URL = 'https://accounts.google.com/o/oauth2/auth?' +
+    remoting.xhr.urlencodeParamHash({
+          'client_id': this.CLIENT_ID_,
+          'redirect_uri': this.REDIRECT_URI_,
+          'scope': this.SCOPE_,
+          'response_type': 'code',
+          'access_type': 'offline',
+          'approval_prompt': 'force'
+        });
+  window.location.replace(GET_CODE_URL);
+};
+
+/**
+ * Asynchronously exchanges an authorization code for a refresh token.
+ *
+ * @param {string} code The new refresh token.
+ * @param {function(XMLHttpRequest):void} onDone Callback to invoke on
+ *     completion.
+ * @return {void} Nothing.
+ */
+remoting.OAuth2.prototype.exchangeCodeForToken = function(code, onDone) {
+  var parameters = {
+    'client_id': this.CLIENT_ID_,
+    'client_secret': this.CLIENT_SECRET_,
+    'redirect_uri': this.REDIRECT_URI_,
+    'code': code,
+    'grant_type': 'authorization_code'
+  };
+
+  /** @type {remoting.OAuth2} */
+  var that = this;
+  /** @param {XMLHttpRequest} xhr The XHR reply. */
+  var processTokenResponse = function(xhr) {
+    that.processTokenResponse_(xhr);
+    onDone(xhr);
+  };
+  remoting.xhr.post(this.OAUTH2_TOKEN_ENDPOINT_,
+                    processTokenResponse,
+                    parameters);
+};
+
+/**
+ * Call myfunc with an access token as the only parameter.
+ *
+ * This will refresh the access token if necessary.  If the access token
+ * cannot be refreshed, an error is thrown.
+ *
+ * The access token will remain valid for at least 2 minutes.
+ *
+ * @param {function(string):void} myfunc
+ *        Function to invoke with access token.
+ * @return {void} Nothing.
+ */
+remoting.OAuth2.prototype.callWithToken = function(myfunc) {
+  /** @type {remoting.OAuth2} */
+  var that = this;
+  if (remoting.oauth2.needsNewAccessToken()) {
+    remoting.oauth2.refreshAccessToken(function() {
+      if (remoting.oauth2.needsNewAccessToken()) {
+        // If we still need it, we're going to infinite loop.
+        throw 'Unable to get access token.';
+      }
+      myfunc(that.getAccessToken());
+    });
+    return;
+  }
+
+  myfunc(this.getAccessToken());
+};
+
+/**
+ * Get the user's email address.
+ *
+ * @param {function(?string):void} setEmail Callback invoked when the email
+ *     address is available, or on error.
+ * @return {void} Nothing.
+ */
+remoting.OAuth2.prototype.getEmail = function(setEmail) {
+  /** @type {remoting.OAuth2} */
+  var that = this;
+  /** @param {XMLHttpRequest} xhr The XHR response. */
+  var onResponse = function(xhr) {
+    that.email = null;
+    if (xhr.status == 200) {
+      // TODO(ajwong): See if we can't find a JSON endpoint.
+      that.email = xhr.responseText.split('&')[0].split('=')[1];
+    }
+    window.localStorage.setItem(that.KEY_EMAIL_, that.email);
+    setEmail(that.email);
+  };
+
+  /** @param {string} token The access token. */
+  var getEmailFromToken = function(token) {
+    var headers = { 'Authorization': 'OAuth ' + token };
+    // TODO(ajwong): Update to new v2 API.
+    remoting.xhr.get('https://www.googleapis.com/userinfo/email',
+                     onResponse, '', headers);
+  };
+
+  this.callWithToken(getEmailFromToken);
+};
+
+/**
+ * If the user's email address is cached, return it, otherwise return null.
+ *
+ * @return {?string} The email address, if it has been cached by a previous call
+ *     to getEmail, otherwise null.
+ */
+remoting.OAuth2.prototype.getCachedEmail = function() {
+  var value = window.localStorage.getItem(this.KEY_EMAIL_);
+  if (typeof value == 'string') {
+    return value;
+  }
+  return null;
+};