//     Zepto.js
//     (c) 2010-2016 Thomas Fuchs
//     Zepto.js may be freely distributed under the MIT license.

;(function($){
    var touch = {},
      touchTimeout, tapTimeout, swipeTimeout, longTapTimeout,
      longTapDelay = 750,
      gesture,
      down, up, move,
      eventMap,
      initialized = false
  
    function swipeDirection(x1, x2, y1, y2) {
      return Math.abs(x1 - x2) >=
        Math.abs(y1 - y2) ? (x1 - x2 > 0 ? 'Left' : 'Right') : (y1 - y2 > 0 ? 'Up' : 'Down')
    }
  
    function longTap() {
      longTapTimeout = null
      if (touch.last) {
        touch.el.trigger('longTap')
        touch = {}
      }
    }
  
    function cancelLongTap() {
      if (longTapTimeout) clearTimeout(longTapTimeout)
      longTapTimeout = null
    }
  
    function cancelAll() {
      if (touchTimeout) clearTimeout(touchTimeout)
      if (tapTimeout) clearTimeout(tapTimeout)
      if (swipeTimeout) clearTimeout(swipeTimeout)
      if (longTapTimeout) clearTimeout(longTapTimeout)
      touchTimeout = tapTimeout = swipeTimeout = longTapTimeout = null
      touch = {}
    }
  
    function isPrimaryTouch(event){
      return (event.pointerType == 'touch' ||
        event.pointerType == event.MSPOINTER_TYPE_TOUCH)
        && event.isPrimary
    }
  
    function isPointerEventType(e, type){
      return (e.type == 'pointer'+type ||
        e.type.toLowerCase() == 'mspointer'+type)
    }
  
    // helper function for tests, so they check for different APIs
    function unregisterTouchEvents(){
      if (!initialized) return
      $(document).off(eventMap.down, down)
        .off(eventMap.up, up)
        .off(eventMap.move, move)
        .off(eventMap.cancel, cancelAll)
      $(window).off('scroll', cancelAll)
      cancelAll()
      initialized = false
    }
  
    function setup(__eventMap){
      var now, delta, deltaX = 0, deltaY = 0, firstTouch, _isPointerType
  
      unregisterTouchEvents()
  
      eventMap = (__eventMap && ('down' in __eventMap)) ? __eventMap :
        ('ontouchstart' in document ?
        { 'down': 'touchstart', 'up': 'touchend',
          'move': 'touchmove', 'cancel': 'touchcancel' } :
        'onpointerdown' in document ?
        { 'down': 'pointerdown', 'up': 'pointerup',
          'move': 'pointermove', 'cancel': 'pointercancel' } :
         'onmspointerdown' in document ?
        { 'down': 'MSPointerDown', 'up': 'MSPointerUp',
          'move': 'MSPointerMove', 'cancel': 'MSPointerCancel' } : false)
  
      // No API availables for touch events
      if (!eventMap) return
  
      if ('MSGesture' in window) {
        gesture = new MSGesture()
        gesture.target = document.body
  
        $(document)
          .bind('MSGestureEnd', function(e){
            var swipeDirectionFromVelocity =
              e.velocityX > 1 ? 'Right' : e.velocityX < -1 ? 'Left' : e.velocityY > 1 ? 'Down' : e.velocityY < -1 ? 'Up' : null
            if (swipeDirectionFromVelocity) {
              touch.el.trigger('swipe')
              touch.el.trigger('swipe'+ swipeDirectionFromVelocity)
            }
          })
      }
  
      down = function(e){
        if((_isPointerType = isPointerEventType(e, 'down')) &&
          !isPrimaryTouch(e)) return
        firstTouch = _isPointerType ? e : e.touches[0]
        if (e.touches && e.touches.length === 1 && touch.x2) {
          // Clear out touch movement data if we have it sticking around
          // This can occur if touchcancel doesn't fire due to preventDefault, etc.
          touch.x2 = undefined
          touch.y2 = undefined
        }
        now = Date.now()
        delta = now - (touch.last || now)
        touch.el = $('tagName' in firstTouch.target ?
          firstTouch.target : firstTouch.target.parentNode)
        touchTimeout && clearTimeout(touchTimeout)
        touch.x1 = firstTouch.pageX
        touch.y1 = firstTouch.pageY
        if (delta > 0 && delta <= 250) touch.isDoubleTap = true
        touch.last = now
        longTapTimeout = setTimeout(longTap, longTapDelay)
        // adds the current touch contact for IE gesture recognition
        if (gesture && _isPointerType) gesture.addPointer(e.pointerId)
      }
  
      move = function(e){
        if((_isPointerType = isPointerEventType(e, 'move')) &&
          !isPrimaryTouch(e)) return
        firstTouch = _isPointerType ? e : e.touches[0]
        cancelLongTap()
        touch.x2 = firstTouch.pageX
        touch.y2 = firstTouch.pageY
  
        deltaX += Math.abs(touch.x1 - touch.x2)
        deltaY += Math.abs(touch.y1 - touch.y2)
      }
  
      up = function(e){
        if((_isPointerType = isPointerEventType(e, 'up')) &&
          !isPrimaryTouch(e)) return
        cancelLongTap()
  
        // swipe
        if ((touch.x2 && Math.abs(touch.x1 - touch.x2) > 30) ||
            (touch.y2 && Math.abs(touch.y1 - touch.y2) > 30))
  
          swipeTimeout = setTimeout(function() {
            if (touch.el){
              touch.el.trigger('swipe')
              touch.el.trigger('swipe' + (swipeDirection(touch.x1, touch.x2, touch.y1, touch.y2)))
            }
            touch = {}
          }, 0)
  
        // normal tap
        else if ('last' in touch)
          // don't fire tap when delta position changed by more than 30 pixels,
          // for instance when moving to a point and back to origin
          if (deltaX < 30 && deltaY < 30) {
            // delay by one tick so we can cancel the 'tap' event if 'scroll' fires
            // ('tap' fires before 'scroll')
            tapTimeout = setTimeout(function() {
  
              // trigger universal 'tap' with the option to cancelTouch()
              // (cancelTouch cancels processing of single vs double taps for faster 'tap' response)
              var event = $.Event('tap')
              event.cancelTouch = cancelAll
              // [by paper] fix -> "TypeError: 'undefined' is not an object (evaluating 'touch.el.trigger'), when double tap
              if (touch.el) touch.el.trigger(event)
  
              // trigger double tap immediately
              if (touch.isDoubleTap) {
                if (touch.el) touch.el.trigger('doubleTap')
                touch = {}
              }
  
              // trigger single tap after 250ms of inactivity
              else {
                touchTimeout = setTimeout(function(){
                  touchTimeout = null
                  if (touch.el) touch.el.trigger('singleTap')
                  touch = {}
                }, 250)
              }
            }, 0)
          } else {
            touch = {}
          }
          deltaX = deltaY = 0
      }
  
      $(document).on(eventMap.up, up)
        .on(eventMap.down, down)
        .on(eventMap.move, move)
  
      // when the browser window loses focus,
      // for example when a modal dialog is shown,
      // cancel all ongoing events
      $(document).on(eventMap.cancel, cancelAll)
  
      // scrolling the window indicates intention of the user
      // to scroll, not tap or swipe, so cancel all ongoing events
      $(window).on('scroll', cancelAll)
  
      initialized = true
    }
  
    ;['swipe', 'swipeLeft', 'swipeRight', 'swipeUp', 'swipeDown',
      'doubleTap', 'tap', 'singleTap', 'longTap'].forEach(function(eventName){
      $.fn[eventName] = function(callback){ return this.on(eventName, callback) }
    })
  
    $.touch = { setup: setup }
  
    $(document).ready(setup)
  })(Zepto)