(function ($) {

  Drupal.behaviors.autologout = {
    attach: function(context, settings) {

      if (context != document) {
        return;
      }

      var paddingTimer;
      var t;
      var theDialog;
      var localSettings;

      // Activity is a boolean used to detect a user has
      // interacted with the page.
      var activity;

      // Timer to keep track of activity resets.
      var activityResetTimer;

      // Prevent settings being overriden by ajax callbacks by cloning the settings.
      localSettings = jQuery.extend(true, {}, settings.autologout);

      if (localSettings.refresh_only) {
        // On pages that cannot be logged out of don't start the logout countdown.
        t = setTimeout(keepAlive, localSettings.timeout);
      }
      else {
        // Set no activity to start with.
        activity = false;

        // Bind formUpdated events to preventAutoLogout event.
        $('body').bind('formUpdated', function(event) {
          $(event.target).trigger('preventAutologout');
        });

        // Support for CKEditor.
        if (typeof CKEDITOR !== 'undefined') {
          CKEDITOR.on('instanceCreated', function(e) {
            e.editor.on('contentDom', function() {
              e.editor.document.on('keyup', function(event) {
                // Keyup event in ckeditor should prevent autologout.
                $(e.editor.element.$).trigger('preventAutologout');
              });
            });
          });
        }

        $('body').bind('preventAutologout', function(event) {
          // When the preventAutologout event fires
          // we set activity to true.
          activity = true;

          // Clear timer if one exists.
          clearTimeout(activityResetTimer);

          // Set a timer that goes off and resets this activity indicator
          // after a minute, otherwise sessions never timeout.
          activityResetTimer = setTimeout(function () {
            activity = false;
          }, 60000);
        });

        // On pages where the user can be logged out, set the timer to popup
        // and log them out.
        t = setTimeout(init, localSettings.timeout);
      }

      function init() {
        var noDialog = Drupal.settings.autologout.no_dialog;

        if (activity) {
          // The user has been active on the page.
          activity = false;
          refresh();
        }
        else {

          // The user has not been active, ask them if they want to stay logged in
          // and start the logout timer.
          paddingTimer = setTimeout(confirmLogout, localSettings.timeout_padding);

          // While the countdown timer is going, lookup the remaining time. If there
          // is more time remaining (i.e. a user is navigating in another tab), then
          // reset the timer for opening the dialog.
          Drupal.ajax['autologout.getTimeLeft'].autologoutGetTimeLeft(function(time) {
              if (time > 0) {
                clearTimeout(paddingTimer);
                t = setTimeout(init, time);
              }
              else {
                // Logout user right away without displaying a confirmation dialog.
                if (noDialog) {
                  logout();
                  return;
                }
                theDialog = dialog();
              }
          });
        }
      }

      function dialog() {
        var buttons = {};
        buttons[Drupal.t('Yes')] = function() {
          $(this).dialog("destroy");
          clearTimeout(paddingTimer);
          refresh();
        };

        buttons[Drupal.t('No')] = function() {
          $(this).dialog("destroy");
          logout();
        };

        return $('<div id="autologout-confirm"> ' +  localSettings.message + '</div>').dialog({
          modal: true,
               closeOnEscape: false,
               width: "auto",
               dialogClass: 'autologout-dialog',
               title: localSettings.title,
               buttons: buttons,
               close: function(event, ui) {
                 logout();
               }
        });
      }

      // A user could have used the reset button on the tab/window they're actively
      // using, so we need to double check before actually logging out.
      function confirmLogout() {
        $(theDialog).dialog('destroy');

        Drupal.ajax['autologout.getTimeLeft'].autologoutGetTimeLeft(function(time) {
          if (time > 0) {
            t = setTimeout(init, time);
          }
          else {
            logout();
          }
        });
      }

      function logout() {
        if (localSettings.use_alt_logout_method) {
          window.location = Drupal.settings.basePath + "?q=autologout_ahah_logout/alt";
        }
        else {
          $.ajax({
            url: Drupal.settings.basePath + "?q=autologout_ahah_logout",
            type: "POST",
            success: function() {
              window.location = localSettings.redirect_url;
            },
            error: function(XMLHttpRequest, textStatus) {
              if (XMLHttpRequest.status == 403 || XMLHttpRequest.status == 404) {
                window.location = localSettings.redirect_url;
              }
            }
          });
        }
      }

      /**
       * Use the Drupal ajax library to handle get time remaining events
       * because if using the JS Timer, the return will update it.
       *
       * @param function callback(time)
       *   The function to run when ajax is successful. The time parameter
       *   is the time remaining for the current user in ms.
       */
      Drupal.ajax.prototype.autologoutGetTimeLeft = function(callback) {
        var ajax = this;

        if (ajax.ajaxing) {
          return false;
        }

        ajax.options.success = function (response, status) {
          if (typeof response == 'string') {
            response = $.parseJSON(response);
          }

          if (typeof response[1].command === 'string' && response[1].command == 'alert') {
            // In the event of an error, we can assume
            // the user has been logged out.
            window.location = localSettings.redirect_url;
          }

          response.forEach(
              function(element) {
                  if(element.command == 'settings')
                  {
                      if (typeof element.settings.time !== 'undefined') {
                          callback(element.settings.time);
                      }
                  }
              }
          );

          // Let Drupal.ajax handle the JSON response.
          return ajax.success(response, status);
        };

        try {
          ajax.beforeSerialize(ajax.element, ajax.options);
          $.ajax(ajax.options);
        }
        catch (e) {
          ajax.ajaxing = false;
        }
      };

      Drupal.ajax['autologout.getTimeLeft'] = new Drupal.ajax(null, $(document.body), {
        url: Drupal.settings.basePath  + '?q=autologout_ajax_get_time_left',
        event: 'autologout.getTimeLeft',
        submit: {
          'ajax_page_state': Drupal.settings.ajaxPageState
        },
        error: function(XMLHttpRequest, textStatus) {
          // Disable error reporting to the screen.
        }
      });

      /**
       * Use the Drupal ajax library to handle refresh events
       * because if using the JS Timer, the return will update
       * it.
       *
       * @param function timerFunction
       *   The function to tell the timer to run after its been
       *   restarted.
       */
      Drupal.ajax.prototype.autologoutRefresh = function(timerfunction) {
        var ajax = this;

        if (ajax.ajaxing) {
          return false;
        }

        ajax.options.success = function (response, status) {
          if (typeof response == 'string') {
            response = $.parseJSON(response);
          }

          if (typeof response[1].command === 'string' && response[1].command == 'alert') {
            // In the event of an error, we can assume
            // the user has been logged out.
            window.location = localSettings.redirect_url;
          }

          t = setTimeout(timerfunction, localSettings.timeout);
          activity = false;

          // Let Drupal.ajax handle the JSON response.
          return ajax.success(response, status);
        };

        try {
          ajax.beforeSerialize(ajax.element, ajax.options);
          $.ajax(ajax.options);
        }
        catch (e) {
          ajax.ajaxing = false;
        }
      };

      Drupal.ajax['autologout.refresh'] = new Drupal.ajax(null, $(document.body), {
        url: Drupal.settings.basePath  + '?q=autologout_ahah_set_last',
        event: 'autologout.refresh',
        submit: {
          'ajax_page_state': Drupal.settings.ajaxPageState
        },
        error: function(XMLHttpRequest, textStatus) {
          // Disable error reporting to the screen.
        }
      });

      function keepAlive() {
        Drupal.ajax['autologout.refresh'].autologoutRefresh(keepAlive);
      }

      function refresh() {
        Drupal.ajax['autologout.refresh'].autologoutRefresh(init);
      }

      // Check if the page was loaded via a back button click.
      var $dirty_bit = $('#autologout-cache-check-bit');
      if ($dirty_bit.length !== 0) {

        if ($dirty_bit.val() == '1') {
          // Page was loaded via a back button click, we should
          // refresh the timer.
          refresh();
        }

        $dirty_bit.val('1');
      }
    }
  };
})(jQuery);
