/*
 * 
 * mnTouch, version 1.2.1
 * Simple AngularJS directive for fast touch events (tap and swipe)
 * 
 * by Alessandro Bellini - ilmente
 *
 */ 

angular.module('mn', []).directive('mnTouch', ['$timeout', function($timeout){
	var touchEngine = function(scope, element, attrs){
		scope.$event = {
			target: element[0],
			threshold: !!attrs.threshold ? attrs.threshold : 10,
			holdfor: !!attrs.holdfor ? attrs.holdfor : 500,
			types: {
				start: 'mousedown',
				move: 'mousemove',
				end: 'mouseup',
				cancel: ''
			},
			coords: {},
			events: {}
		};
		
		var fn = function(eventName){
			scope.$event.name = eventName;

			if (!!attrs[eventName]){
				scope.$eval(attrs[eventName]);
				scope.$apply();
			}
		};
		
		var getCoords = function(event){
			return {
				x: event.pageX || 0,
				y: event.pageY || 0
			}
		};
		
		if (typeof window.ontouchstart !== 'undefined' 
			&& typeof window.ontouchend !== 'undefined'
			&& typeof window.ontouchcancel !== 'undefined'){

			scope.$event.types.start = 'touchstart';
			scope.$event.types.move = 'touchmove';
			scope.$event.types.end = 'touchend';
			scope.$event.types.cancel = 'touchcancel';

			getCoords = function(event){
				var coords = !!event 
					&& !!event.changedTouches 
					&& !!event.changedTouches.length > 0
					? event.changedTouches[0]
					: {};
				
				return {
					x: coords.pageX || event.pageX || 0,
					y: coords.pageY || event.pageY || 0
				}
			}
		} else if (window.navigator.pointerEnabled){
			scope.$event.types.start = 'pointerdown';
			scope.$event.types.move = 'pointermove';
			scope.$event.types.end = 'pointerup';
		} else if (window.navigator.msPointerEnabled){
			scope.$event.types.start = 'MSPointerDown';
			scope.$event.types.move = 'MSPointerMove';
			scope.$event.types.end = 'MSPointerUp'; 
			scope.$event.types.cancel = 'MSPointerOut';
		}
		
		if (!!attrs['tap']){
			scope.$event.isSecure = false;
			scope.$event.isRunning = false;

			var onStartEvent = function(startEvent){
				scope.$event.events.start = startEvent;
				scope.$event.coords.start = getCoords(startEvent);
				fn('tap');
			};

			scope.$event.target.addEventListener(scope.$event.types.start, onStartEvent, false);
		} else {
			scope.$event.isSecure = true;

			var onStartEvent = function(startEvent){
				scope.$event.isRunning = true;
				scope.$event.events.start = startEvent;
				scope.$event.coords.start = getCoords(startEvent);

				if (!!attrs['hold']){
					$timeout(function(){
						if (scope.$event.isRunning){
							scope.$event.target.addEventListener(scope.$event.types.move, onMoveEvent, false);
						}

						$timeout(function(){
							if (scope.$event.isRunning){
								onMoveEvent(startEvent);
							}
						}, 32, false);
					}, scope.$event.holdfor, false);
				}
			};

			var onEndEvent = function(endEvent, isHold){
				if (scope.$event.isRunning){
					scope.$event.isRunning = false;
					scope.$event.events.end = endEvent;
					scope.$event.coords.end = getCoords(endEvent);
					scope.$event.directionX = scope.$event.coords.end.x - scope.$event.coords.start.x;
					scope.$event.directionY = scope.$event.coords.end.y - scope.$event.coords.start.y;
					scope.$event.offsetX = Math.abs(scope.$event.directionX);
					scope.$event.offsetY = Math.abs(scope.$event.directionY);
					
					if (scope.$event.offsetX <= scope.$event.threshold && scope.$event.offsetY <= scope.$event.threshold){
						if (!!isHold) fn('hold');
						else fn('secureTap');
					}
					else if (scope.$event.offsetX >= scope.$event.offsetY) fn(scope.$event.directionX > 0 ? 'swipeRight' : 'swipeLeft');
					else fn(scope.$event.directionY > 0 ? 'swipeDown' : 'swipeUp');
				}
			};

			var onMoveEvent = function(moveEvent){
				scope.$event.target.removeEventListener(scope.$event.types.move, onMoveEvent, false);
				onEndEvent(moveEvent, true);
			};

			scope.$event.target.addEventListener(scope.$event.types.start, onStartEvent, false);
			scope.$event.target.addEventListener(scope.$event.types.end, onEndEvent, false);
			if (!!scope.$event.types.cancel) scope.$event.target.addEventListener(scope.$event.types.cancel, onEndEvent, false);
		}
	};
	
    return {
		restrict: 'A',
        link: touchEngine
    }
}]);