/*!
 * jQuery UI Touch Punch 0.2.3
 *
 * Copyright 2011–2014, Dave Furfero
 * Dual licensed under the MIT or GPL Version 2 licenses.
 *
 * Depends:
 *  jQuery.ui.widget.js
 *  jQuery.ui.mouse.js
 */
import { Injectable } from '@angular/core'

@Injectable()
export class TouchPunchProvider {
  constructor() {}

  init() {
    (function ($) {

    // Detect touch support
    console.log('touchPunch is available');
    $.support.touch = 'ontouchend' in document;

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

    var mouseProto = $.ui.mouse.prototype,
        _mouseInit = mouseProto._mouseInit,
        _mouseDestroy = mouseProto._mouseDestroy,
        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'),
        touchmove: $.proxy(self, '_touchMove'),
        touchend: $.proxy(self, '_touchEnd')
      });

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

    /**
     * Remove the touch event handlers
     */
    mouseProto._mouseDestroy = function () {
      
      var self = this;

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

      // Call the original $.ui.mouse destroy method
      _mouseDestroy.call(self);
    };

  })(jQuery);
  }
  
}