/**
 * jQuery Plugin to obtain touch gestures from iPhone, iPod Touch and iPad, should also work with Android mobile phones (not tested yet!)
 * Common usage: wipe images (left and right to show the previous or next image)
 *
 * @author Andreas Waltl, netCU Internetagentur (http://www.netcu.de)
 * @version 1.0 (15th July 2010)
 */
(function($) {
   $.fn.touchwipe = function(settings) {
     var config = {
    		min_move: 20,
 			wipe: function(d) { alert(d); },
			preventDefaultEvents: true
	 };

     if (settings) $.extend(config, settings);

     this.each(function() {
    	 var startX;
    	 var startY;
		 var isMoving = false;

    	 function cancelTouch() {
    		 this.removeEventListener('touchmove', onTouchMove);
    		 startX = null;
    		 startY = null;
    		 isMoving = false;
    	 }

    	 function onTouchMove(e) {
    		 if(config.preventDefaultEvents) {
    			 e.preventDefault();
    		 }
    		 if(isMoving) {
	    		 var x = e.touches[0].pageX;
	    		 var y = e.touches[0].pageY;
	    		 var dx = startX - x;
	    		 var dy = startY - y;
	    		 if(Math.abs(dx) >= config.min_move) {
	    			cancelTouch();
	    			if(dx > 0) {
	    				config.wipe('left');
	    			} else {
	    				config.wipe('right');
	    			}
	    		 }
	    		 if(Math.abs(dy) >= config.min_move) {
	    			cancelTouch();
	    			if(dy > 0) {
	    				config.wipe('up');
	    			} else {
	    				config.wipe('down');
	    			}
	    		 }
    		 }
    	 }

    	 function onTouchStart(e)
    	 {
    		 if (e.touches.length == 1) {
    			 startX = e.touches[0].pageX;
    			 startY = e.touches[0].pageY;
    			 isMoving = true;
    			 this.addEventListener('touchmove', onTouchMove, false);
    		 }
    	 }

		 this.addEventListener('touchstart', onTouchStart, false);
     });

     return this;
   };

 })(jQuery);