/*!
* jQuery UI Touch Punch 0.2.2
*
* Copyright 2011, Dave Furfero
* Dual licensed under the MIT or GPL Version 2 licenses.
*
* Depends:
* jquery.ui.widget.js
* jquery.ui.mouse.js
*/
(function ($) {

    // Detect touch support
    $.support.touch = 'ontouchend' in document;

    // Ignore browsers without touch support
    if (!$.support.touch) {
        return;
    }

    var mouseProto = $.ui.mouse.prototype,
    _mouseInit = mouseProto._mouseInit,
    touchHandled;

    /**
* Simulate a mouse event based on a corresponding touch event
* @param {Object} event A touch event
* @param {String} simulatedType The corresponding mouse event
*/
    function simulateMouseEvent (event, simulatedType) {

        // Ignore multi-touch events
        if (event.originalEvent.touches.length > 1) {
            return;
        }

        event.preventDefault();

        var touch = event.originalEvent.changedTouches[0],
        simulatedEvent = document.createEvent('MouseEvents');
    
        // Initialize the simulated mouse event using the touch event's coordinates
        simulatedEvent.initMouseEvent(
            simulatedType, // type
            true, // bubbles
            true, // cancelable
            window, // view
            1, // detail
            touch.screenX, // screenX
            touch.screenY, // screenY
            touch.clientX, // clientX
            touch.clientY, // clientY
            false, // ctrlKey
            false, // altKey
            false, // shiftKey
            false, // metaKey
            0, // button
            null // relatedTarget
            );

        // Dispatch the simulated event to the target element
        event.target.dispatchEvent(simulatedEvent);
    }

    /**
* Handle the jQuery UI widget's touchstart events
* @param {Object} event The widget element's touchstart event
*/
    mouseProto._touchStart = function (event) {

        var self = this;

        // Ignore the event if another widget is already being handled
        if (touchHandled || !self._mouseCapture(event.originalEvent.changedTouches[0])) {
            return;
        }

        // Set the flag to prevent other widgets from inheriting the touch event
        touchHandled = true;

        // Track movement to determine if interaction was a click
        self._touchMoved = false;

        // Simulate the mouseover event
        simulateMouseEvent(event, 'mouseover');

        // Simulate the mousemove event
        simulateMouseEvent(event, 'mousemove');

        // Simulate the mousedown event
        simulateMouseEvent(event, 'mousedown');
    };

    /**
* Handle the jQuery UI widget's touchmove events
* @param {Object} event The document's touchmove event
*/
    mouseProto._touchMove = function (event) {

        // Ignore event if not handled
        if (!touchHandled) {
            return;
        }

        // Interaction was not a click
        this._touchMoved = true;

        // Simulate the mousemove event
        simulateMouseEvent(event, 'mousemove');
    };

    /**
* Handle the jQuery UI widget's touchend events
* @param {Object} event The document's touchend event
*/
    mouseProto._touchEnd = function (event) {

        // Ignore event if not handled
        if (!touchHandled) {
            return;
        }

        // Simulate the mouseup event
        simulateMouseEvent(event, 'mouseup');

        // Simulate the mouseout event
        simulateMouseEvent(event, 'mouseout');

        // If the touch interaction did not move, it should trigger a click
        if (!this._touchMoved) {

            // Simulate the click event
            simulateMouseEvent(event, 'click');
        }

        // Unset the flag to allow other widgets to inherit the touch event
        touchHandled = false;
    };

    /**
* A duck punch of the $.ui.mouse _mouseInit method to support touch events.
* This method extends the widget with bound touch event handlers that
* translate touch events to mouse events and pass them to the widget's
* original mouse event handling methods.
*/
    mouseProto._mouseInit = function () {
    
        var self = this;

        // Delegate the touch handlers to the widget's element
        self.element
        .bind('touchstart', $.proxy(self, '_touchStart'))
        .bind('touchmove', $.proxy(self, '_touchMove'))
        .bind('touchend', $.proxy(self, '_touchEnd'));

        // Call the original $.ui.mouse init method
        _mouseInit.call(self);
    };

})(jQuery);