epilgrim.sessionTimeoutHandler.js

(function($, window, undefined){
  $.widget( "epilgrim.sessionTimeoutHandler", {
    options: {
      // default options
      title :                  'Session Timeout',
      message :                'Your session is about to expire.',
      keepAliveUrl :           'keepAlive.php',
      retrieveTimeLeftUrl :    'retrieveTimeLeft.php',
      redirUrl :               false,
      logoutUrl :              'logout.php',
      defaultSessionTime:       false,
      warnWhenLeft :            300000,
      checkTimeBeforeRedirect:  true,
      checkTimeBeforePopup:     false,
      errorGettingSessionTimeLeft:  'There was an error retrieving session information from the server. Session could be timed out',
      modalId:                 'sessionTimeout-dialog',

      // callbacks
      logOutNow: function(event, data) {
        window.location = data.plugin.options.logoutUrl;
      },
      redirectNow: function(event, data) {
        window.location = data.plugin.options.redirUrl;
      },
      stayConnected: function(event, data) {
        data.plugin.modal.dialog('close');
        data.plugin._trigger(
          'getSessionTimeLeft',
          null,
          {
            plugin: data.plugin,
            updateSession: true,
            callback: $.proxy(
              function(time){
                this.initializeTimers(time);
              }, data.plugin
            )
          }
        );
      },
      getSessionTimeLeft: function (event, data) {
        var action = data.updateSession ? data.plugin.options.keepAliveUrl : data.plugin.options.retrieveTimeLeftUrl;
        var self = data.plugin;
        $.ajax({
          context: self,
          dataType: "json",
          url: action,
          success: function (time){
            var timeLeft = time * 1000;
            data.callback.call(self, timeLeft);
            if (timeLeft > this.options.warnWhenLeft) {
              this.modal.dialog('close');
            }
          },
          error: function(){
            alert(self.options.errorGettingSessionTimeLeft);
          }
        });
      }
    },
    // the constructor
    _create: function() {
      // Create timeout warning dialog
      this.dialogTimer = null;

      // timer for redirecting
      this.redirectTimer = null;

      if (this.options.redirUrl == false){
        this.options.redirUrl = this.options.logoutUrl;
      }

      this._createModal();

      this.initializeTimers(this.options.defaultSessionTime);
    },
    _createModal: function(){
      var self = this;
      this.modal = jQuery('<div/>', {
        id: this.options.modalId,
        title: this.options.title,
        text: this.options.message
      });
      this.modal.appendTo(this.element);

      this.modal.dialog({
        autoOpen: false,
        width: 400,
        modal: true,
        closeOnEscape: false,
        open: function(event, ui) {
          $(".ui-dialog-titlebar-close", this.modal).hide();
        },
        buttons: {
          // Button one - takes user to logout URL
          "Log Out Now": function() {
            self._trigger('logOutNow', null, { plugin: self });
          },
          // Button two - closes dialog and makes call to keep-alive URL
          "Stay Connected": function() {
            self._trigger('stayConnected', null, { plugin: self });
          }
        }
      });
    },
    _destroy: function() {
      // remove generated elements
      this.modal.remove();
    },
    _dialogTimer: function(action, time ){
      switch(action) {
        case 'start':
          this.dialogTimer = setTimeout($.proxy(this._dialogHandler, this), time);
          break;
        case 'stop':
          clearTimeout(this.dialogTimer);
          break;
        case 'restart':
          this._dialogTimer('stop');
          this._dialogTimer('start', time);
          break;
      }
    },
    _redirectTimer: function(action, time ){
      switch(action) {
        case 'start':
          this.redirectTimer = setTimeout($.proxy(this._redirectHandler, this), time);
          break;
        case 'stop':
          clearTimeout(this.redirectTimer);
          break;
        case 'restart':
          this._redirectTimer('stop');
          this._redirectTimer('start', time);
          break;
      }
    },
    _dialogHandler: function(){
      if(this.options.checkTimeBeforePopup){
        this._trigger('getSessionTimeLeft', null, {plugin: this, updateSession: false, callback: function(timeLeft){
          if (timeLeft <= this.options.warnWhenLeft){
            this.modal.dialog('open');
          } else {
            this.initializeTimers(timeLeft);
          }
        }});
      }else{
        this.modal.dialog('open');
      }
    },
    _redirectHandler: function(){
      if (this.options.checkTimeBeforeRedirect){
        this._trigger('getSessionTimeLeft', null, {plugin: this, updateSession: false, callback: function(time){
          if (time <= 0){
            this._trigger('redirectNow', null, {plugin: this});
          } else {
            this.initializeTimers(time);
          }
        }});
      } else {
        this._trigger('redirectNow', null, {plugin: this});
      }
    },
    _setTimers: function (time){
      var action;

      action = this.dialogTimer === null ? 'start' : 'restart';
      this._dialogTimer( action, (time - this.options.warnWhenLeft));

      action = this.redirectTimer === null ? 'start' : 'restart';
      this._redirectTimer ( action, time);
    },
    initializeTimers: function (time){
      if ( time === false){
        // if no time variable was passed, get it from the server
        this._trigger('getSessionTimeLeft', null, {plugin: this, updateSession: false, callback: this._setTimers});
      } else {
        // when time variable passed, set it
        this._setTimers(time);
      }
    }
  });
})(jQuery, window);