/**
* Copyright © Magento, Inc. All rights reserved.
* See COPYING.txt for license details.
*/

define([
'jquery',
'underscore',
'jquery-ui-modules/slider'
], function ($, _) {
'use strict';

/**
* Adds support for touch events for regular jQuery UI slider.
*/
$.widget('mage.touchSlider', $.ui.slider, {

/**
* Creates instance of widget.
*
* @override
*/
_create: function () {
_.bindAll(
this,
'_mouseDown',
'_mouseMove',
'_onTouchEnd'
);

return this._superApply(arguments);
},

/**
* Initializes mouse events on element.
* @override
*/
_mouseInit: function () {
var result = this._superApply(arguments);

this.element
.off('mousedown.' + this.widgetName)
.on('touchstart.' + this.widgetName, this._mouseDown);

return result;
},

/**
* Elements' 'mousedown' event handler polyfill.
* @override
*/
_mouseDown: function (event) {
var prevDelegate = this._mouseMoveDelegate,
result;

event = this._touchToMouse(event);
result = this._super(event);

if (prevDelegate === this._mouseMoveDelegate) {
return result;
}

$(document)
.off('mousemove.' + this.widgetName)
.off('mouseup.' + this.widgetName);

$(document)
.on('touchmove.' + this.widgetName, this._mouseMove)
.on('touchend.' + this.widgetName, this._onTouchEnd)
.on('tochleave.' + this.widgetName, this._onTouchEnd);

return result;
},

/**
* Documents' 'mousemove' event handler polyfill.
*
* @override
* @param {Event} event - Touch event object.
*/
_mouseMove: function (event) {
event = this._touchToMouse(event);

return this._super(event);
},

/**
* Documents' 'touchend' event handler.
*/
_onTouchEnd: function (event) {
$(document).trigger('mouseup');

return this._mouseUp(event);
},

/**
* Removes previously assigned touch handlers.
*
* @override
*/
_mouseUp: function () {
this._removeTouchHandlers();

return this._superApply(arguments);
},

/**
* Removes previously assigned touch handlers.
*
* @override
*/
_mouseDestroy: function () {
this._removeTouchHandlers();

return this._superApply(arguments);
},

/**
* Removes touch events from document object.
*/
_removeTouchHandlers: function () {
$(document)
.off('touchmove.' + this.widgetName)
.off('touchend.' + this.widgetName)
.off('touchleave.' + this.widgetName);
},

/**
* Adds properties to the touch event to mimic mouse event.
*
* @param {Event} event - Touch event object.
* @returns {Event}
*/
_touchToMouse: function (event) {
var orig = event.originalEvent,
touch = orig.touches[0];

return _.extend(event, {
which: 1,
pageX: touch.pageX,
pageY: touch.pageY,
clientX: touch.clientX,
clientY: touch.clientY,
screenX: touch.screenX,
screenY: touch.screenY
});
}
});

return $.mage.touchSlider;
});