/* Modified to pass the event to the calling function for move and cancel
---

name: Touch
description: Class to aid the retrieval of the cursor movements
license: MIT-Style License (http://mootools.net/license.txt)
copyright: Valerio Proietti (http://mad4milk.net)
requires: [Core/MooTools, Core/Array, Core/Function, Core/Number, Core/String, Core/Class, Core/Events, Core/Element]
provides: Touch

...
*/

var Touch = new Class({
    
    Implements: Events,
    
    initialize: function(element){
        this.element = document.id(element);
        
        this.bound = {
            start: this.start.bind(this),
            move: this.move.bind(this),
            end: this.end.bind(this)
        };
        
        if (Browser.Platform.ipod){
            this.context = this.element;
            this.startEvent = 'touchstart';
            this.endEvent = 'touchend';
            this.moveEvent = 'touchmove';
        } else {
            this.context = document;
            this.startEvent = 'mousedown';
            this.endEvent = 'mouseup';
            this.moveEvent = 'mousemove';
        }
        
        this.attach();
    },
    
    // public methods
    
    attach: function(){
        this.element.addListener(this.startEvent, this.bound.start);
    },
    
    detach: function(){
        this.element.removeListener(this.startEvent, this.bound.start);
    },
    
    // protected methods
    
    start: function(event){
        this.preventDefault(event);
        // this prevents the copy-paste dialog to show up when dragging. it only affects mobile safari.
        document.body.style.WebkitUserSelect = 'none';
        
        this.hasDragged = false;
        
        this.context.addListener(this.moveEvent, this.bound.move);
        this.context.addListener(this.endEvent, this.bound.end);
        
        var page = this.getPage(event);
            
        this.startX = page.pageX;
        this.startY = page.pageY;
        
        this.fireEvent('start');
    },
    
    move: function(event){
        this.preventDefault(event);
        
        var page = this.getPage(event);
        
        this.deltaX = page.pageX - this.startX;
        this.deltaY = page.pageY - this.startY;
        
        this.hasDragged = !(this.deltaX === 0 && this.deltaY === 0);
        
        if (this.hasDragged) this.fireEvent('move', [this.deltaX, this.deltaY, event]);
    },
    
    end: function(event){
        this.preventDefault(event);
        // we re-enable the copy-paste dialog on drag end
        document.body.style.WebkitUserSelect = '';
        
        this.context.removeListener(this.moveEvent, this.bound.move);
        this.context.removeListener(this.endEvent, this.bound.end);

        this.fireEvent((this.hasDragged) ? 'end' : 'cancel', [event]);
    },
    
    preventDefault: function(event){
        if (event.preventDefault) event.preventDefault();
        else event.returnValue = false;
    },
    
    getPage: function(event){
        //when on mobile safari, the coordinates information is inside the targetTouches object
        if (event.targetTouches) event = event.targetTouches[0];
        if (event.pageX != null && event.pageY != null) return {pageX: event.pageX, pageY: event.pageY};
        var element = (!document.compatMode || document.compatMode == 'CSS1Compat') ? document.documentElement : document.body;
        return {pageX: event.clientX + element.scrollLeft, pageY: event.clientY + element.scrollTop};
    }
    
});