/*
 * jQuery idleTimer plugin
 * version 0.8.092209
 * by Paul Irish. 
 *   http://github.com/paulirish/yui-misc/tree/
 * MIT license
 
 * adapted from YUI idle timer by nzakas:
 *   http://github.com/nzakas/yui-misc/
 
 
 * Copyright (c) 2009 Nicholas C. Zakas
 * 
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to deal
 * in the Software without restriction, including without limitation the rights
 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 * copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 * 
 * The above copyright notice and this permission notice shall be included in
 * all copies or substantial portions of the Software.
 * 
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
 * THE SOFTWARE.
 */

(function($){
	$.idleTimer = function f(newTimeout){
	    //$.idleTimer.tId = -1     //timeout ID
	
	    var idle    = false,        //indicates if the user is idle
	        enabled = true,        //indicates if the idle timer is enabled
	        timeout = 1500000,        //the amount of time (ms) before the user is considered idle
	        events  = 'mousemove keydown DOMMouseScroll mousewheel mousedown', // activity is one of these events
	      //f.olddate = undefined, // olddate used for getElapsedTime. stored on the function
	        
	    /* (intentionally not documented)
	     * Toggles the idle state and fires an appropriate event.
	     * @return {void}
	     */
	    toggleIdleState = function(){
	        //toggle the state
	        idle = !idle;
	        // reset timeout counter
	        f.olddate = +new Date;
	        //fire appropriate event
	        $(document).trigger(  $.data(document,'idleTimer', idle ? "idle" : "active" )  + '.idleTimer');            
	    },
	
	    /**
	     * Stops the idle timer. This removes appropriate event handlers
	     * and cancels any pending timeouts.
	     * @return {void}
	     * @method stop
	     * @static
	     */         
	    stop = function(){
	        //set to disabled
	        enabled = false;
	        //clear any pending timeouts
	        clearTimeout($.idleTimer.tId);
	        //detach the event handlers
	        $(document).unbind('.idleTimer');
	    },
	    
	    /* (intentionally not documented)
	     * Handles a user event indicating that the user isn't idle.
	     * @param {Event} event A DOM2-normalized event object.
	     * @return {void}
	     */
	    handleUserEvent = function(){
	        //clear any existing timeout
	        clearTimeout($.idleTimer.tId);
	        //if the idle timer is enabled
	        if (enabled){
	            //if it's idle, that means the user is no longer idle
	            if (idle){
	                toggleIdleState();           
	            } 
	            //set a new timeout
	            $.idleTimer.tId = setTimeout(toggleIdleState, timeout);
	        }    
	     };
	    
	      
	    /**
	     * Starts the idle timer. This adds appropriate event handlers
	     * and starts the first timeout.
	     * @param {int} newTimeout (Optional) A new value for the timeout period in ms.
	     * @return {void}
	     * @method $.idleTimer
	     * @static
	     */ 
	    f.olddate = f.olddate || +new Date;
	    //assign a new timeout if necessary
	    if (typeof newTimeout == "number"){
	        timeout = newTimeout;
	    } else if (newTimeout === 'destroy') {
	        stop();
	        return this;  
	    } else if (newTimeout === 'getElapsedTime'){
	        return (+new Date) - f.olddate;
	    }
	    //assign appropriate event handlers
	    $(document).bind($.trim((events+' ').split(' ').join('.idleTimer ')),handleUserEvent);
	    //set a timeout to toggle state
	    $.idleTimer.tId = setTimeout(toggleIdleState, timeout);
	    // assume the user is active for the first x seconds.
	    $.data(document,'idleTimer',"active");
	}; // end of $.idleTimer()
})(jQuery);