// Copyright (c) 2012 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
 * Functions related to controlling the modal UI state of the app. UI states
 * are expressed as HTML attributes with a dotted hierarchy. For example, the
 * string 'host.shared' will match any elements with an associated attribute
 * of 'host' or 'host.shared', showing those elements and hiding all others.
 * Elements with no associated attribute are ignored.
 */

'use strict';

/** @suppress {duplicate} */
var remoting = remoting || {};

/** @enum {string} */
// TODO(jamiewalch): Move 'in-session' to a separate web-page so that the
// 'home' state applies to all elements and can be removed.
remoting.AppMode = {
  HOME: 'home',
    UNAUTHENTICATED: 'home.auth',
    HOST: 'home.host',
      HOST_WAITING_FOR_CODE: 'home.host.waiting-for-code',
      HOST_WAITING_FOR_CONNECTION: 'home.host.waiting-for-connection',
      HOST_SHARED: 'home.host.shared',
      HOST_SHARE_FAILED: 'home.host.share-failed',
      HOST_SHARE_FINISHED: 'home.host.share-finished',
    CLIENT: 'home.client',
      CLIENT_UNCONNECTED: 'home.client.unconnected',
      CLIENT_PIN_PROMPT: 'home.client.pin-prompt',
      CLIENT_CONNECTING: 'home.client.connecting',
      CLIENT_CONNECT_FAILED_IT2ME: 'home.client.connect-failed.it2me',
      CLIENT_CONNECT_FAILED_ME2ME: 'home.client.connect-failed.me2me',
      CLIENT_SESSION_FINISHED_IT2ME: 'home.client.session-finished.it2me',
      CLIENT_SESSION_FINISHED_ME2ME: 'home.client.session-finished.me2me',
    HISTORY: 'home.history',
    CONFIRM_HOST_DELETE: 'home.confirm-host-delete',
    ASK_PIN: 'home.ask-pin',
  IN_SESSION: 'in-session'
};

/**
 * @param {Element} element The element to check.
 * @param {string} attr The attribute on the element to check.
 * @param {string} mode The mode to check for.
 * @return {boolean} True if |mode| is found within the element's |attr|.
 */
remoting.hasModeAttribute = function(element, attr, mode) {
  return element.getAttribute(attr).match(
      new RegExp('(\\s|^)' + mode + '(\\s|$)')) != null;
};

/**
 * Update the DOM by showing or hiding elements based on whether or not they
 * have an attribute matching the specified name.
 * @param {string} mode The value against which to match the attribute.
 * @param {string} attr The attribute name to match.
 * @return {void} Nothing.
 */
remoting.updateModalUi = function(mode, attr) {
  var modes = mode.split('.');
  for (var i = 1; i < modes.length; ++i)
    modes[i] = modes[i - 1] + '.' + modes[i];
  var elements = document.querySelectorAll('[' + attr + ']');
  for (var i = 0; i < elements.length; ++i) {
    var element = /** @type {Element} */ elements[i];
    var hidden = true;
    for (var m = 0; m < modes.length; ++m) {
      if (remoting.hasModeAttribute(element, attr, modes[m])) {
        hidden = false;
        break;
      }
    }
    element.hidden = hidden;
    if (!hidden) {
      var autofocusNode = element.querySelector('[autofocus]');
      if (autofocusNode) {
        autofocusNode.focus();
      }
    }
  }
};

/**
 * @type {remoting.AppMode} The current app mode
 */
remoting.currentMode = remoting.AppMode.HOME;

/**
 * Change the app's modal state to |mode|, determined by the data-ui-mode
 * attribute.
 *
 * @param {remoting.AppMode} mode The new modal state.
 */
remoting.setMode = function(mode) {
  remoting.updateModalUi(mode, 'data-ui-mode');
  console.log('App mode: ' + mode);
  remoting.currentMode = mode;
  if (mode == remoting.AppMode.IN_SESSION) {
    document.removeEventListener('keydown', remoting.ConnectionStats.onKeydown,
                                 false);
  } else {
    document.addEventListener('keydown', remoting.ConnectionStats.onKeydown,
                              false);
  }
  if (mode == remoting.AppMode.HOME) {
    var display = function() { remoting.hostList.display(); };
    remoting.hostList.refresh(display);
  }
};

/**
 * Get the major mode that the app is running in.
 * @return {string} The app's current major mode.
 */
remoting.getMajorMode = function() {
  return remoting.currentMode.split('.')[0];
};