GBRSWN/CZKJ.GBRS2.Web/wwwroot/assets/plugins/hammer.js

(function(window, document, exportName, undefined) {
    'use strict';
  
  var VENDOR_PREFIXES = ['', 'webkit', 'moz', 'MS', 'ms', 'o'];
  var TEST_ELEMENT = document.createElement('div');
  
  var TYPE_FUNCTION = 'function';
  
  var round = Math.round;
  var abs = Math.abs;
  var now = Date.now;
  
  /**
   * set a timeout with a given scope
   * @param {Function} fn
   * @param {Number} timeout
   * @param {Object} context
   * @returns {number}
   */
  function setTimeoutContext(fn, timeout, context) {
      return setTimeout(bindFn(fn, context), timeout);
  }
  
  /**
   * if the argument is an array, we want to execute the fn on each entry
   * if it aint an array we don't want to do a thing.
   * this is used by all the methods that accept a single and array argument.
   * @param {*|Array} arg
   * @param {String} fn
   * @param {Object} [context]
   * @returns {Boolean}
   */
  function invokeArrayArg(arg, fn, context) {
      if (Array.isArray(arg)) {
          each(arg, context[fn], context);
          return true;
      }
      return false;
  }
  
  /**
   * walk objects and arrays
   * @param {Object} obj
   * @param {Function} iterator
   * @param {Object} context
   */
  function each(obj, iterator, context) {
      var i, len;
  
      if (!obj) {
          return;
      }
  
      if (obj.forEach) {
          obj.forEach(iterator, context);
      } else if (obj.length !== undefined) {
          for (i = 0, len = obj.length; i < len; i++) {
              iterator.call(context, obj[i], i, obj);
          }
      } else {
          for (i in obj) {
              obj.hasOwnProperty(i) && iterator.call(context, obj[i], i, obj);
          }
      }
  }
  
  /**
   * extend object.
   * means that properties in dest will be overwritten by the ones in src.
   * @param {Object} dest
   * @param {Object} src
   * @param {Boolean} [merge]
   * @returns {Object} dest
   */
  function extend(dest, src, merge) {
      var keys = Object.keys(src);
      for (var i = 0, len = keys.length; i < len; i++) {
          if (!merge || (merge && dest[keys[i]] === undefined)) {
              dest[keys[i]] = src[keys[i]];
          }
      }
      return dest;
  }
  
  /**
   * merge the values from src in the dest.
   * means that properties that exist in dest will not be overwritten by src
   * @param {Object} dest
   * @param {Object} src
   * @returns {Object} dest
   */
  function merge(dest, src) {
      return extend(dest, src, true);
  }
  
  /**
   * simple class inheritance
   * @param {Function} child
   * @param {Function} base
   * @param {Object} [properties]
   */
  function inherit(child, base, properties) {
      var baseP = base.prototype,
          childP;
  
      childP = child.prototype = Object.create(baseP);
      childP.constructor = child;
      childP._super = baseP;
  
      if (properties) {
          extend(childP, properties);
      }
  }
  
  /**
   * simple function bind
   * @param {Function} fn
   * @param {Object} context
   * @returns {Function}
   */
  function bindFn(fn, context) {
      return function boundFn() {
          return fn.apply(context, arguments);
      };
  }
  
  /**
   * let a boolean value also be a function that must return a boolean
   * this first item in args will be used as the context
   * @param {Boolean|Function} val
   * @param {Array} [args]
   * @returns {Boolean}
   */
  function boolOrFn(val, args) {
      if (typeof val == TYPE_FUNCTION) {
          return val.apply(args ? args[0] || undefined : undefined, args);
      }
      return val;
  }
  
  /**
   * use the val2 when val1 is undefined
   * @param {*} val1
   * @param {*} val2
   * @returns {*}
   */
  function ifUndefined(val1, val2) {
      return (val1 === undefined) ? val2 : val1;
  }
  
  /**
   * addEventListener with multiple events at once
   * @param {HTMLElement} element
   * @param {String} types
   * @param {Function} handler
   */
  function addEventListeners(element, types, handler) {
      each(splitStr(types), function(type) {
          element.addEventListener(type, handler, false);
      });
  }
  
  /**
   * removeEventListener with multiple events at once
   * @param {HTMLElement} element
   * @param {String} types
   * @param {Function} handler
   */
  function removeEventListeners(element, types, handler) {
      each(splitStr(types), function(type) {
          element.removeEventListener(type, handler, false);
      });
  }
  
  /**
   * find if a node is in the given parent
   * @method hasParent
   * @param {HTMLElement} node
   * @param {HTMLElement} parent
   * @return {Boolean} found
   */
  function hasParent(node, parent) {
      while (node) {
          if (node == parent) {
              return true;
          }
          node = node.parentNode;
      }
      return false;
  }
  
  /**
   * small indexOf wrapper
   * @param {String} str
   * @param {String} find
   * @returns {Boolean} found
   */
  function inStr(str, find) {
      return str.indexOf(find) > -1;
  }
  
  /**
   * split string on whitespace
   * @param {String} str
   * @returns {Array} words
   */
  function splitStr(str) {
      return str.trim().split(/\s+/g);
  }
  
  /**
   * find if a array contains the object using indexOf or a simple polyFill
   * @param {Array} src
   * @param {String} find
   * @param {String} [findByKey]
   * @return {Boolean|Number} false when not found, or the index
   */
  function inArray(src, find, findByKey) {
      if (src.indexOf && !findByKey) {
          return src.indexOf(find);
      } else {
          for (var i = 0, len = src.length; i < len; i++) {
              if ((findByKey && src[i][findByKey] == find) || (!findByKey && src[i] === find)) {
                  return i;
              }
          }
          return -1;
      }
  }
  
  /**
   * convert array-like objects to real arrays
   * @param {Object} obj
   * @returns {Array}
   */
  function toArray(obj) {
      return Array.prototype.slice.call(obj, 0);
  }
  
  /**
   * unique array with objects based on a key (like 'id') or just by the array's value
   * @param {Array} src [{id:1},{id:2},{id:1}]
   * @param {String} [key]
   * @param {Boolean} [sort=False]
   * @returns {Array} [{id:1},{id:2}]
   */
  function uniqueArray(src, key, sort) {
      var results = [];
      var values = [];
      for (var i = 0, len = src.length; i < len; i++) {
          var val = key ? src[i][key] : src[i];
          if (inArray(values, val) < 0) {
              results.push(src[i]);
          }
          values[i] = val;
      }
  
      if (sort) {
          if (!key) {
              results = results.sort();
          } else {
              results = results.sort(function sortUniqueArray(a, b) {
                  return a[key] > b[key];
              });
          }
      }
  
      return results;
  }
  
  /**
   * get the prefixed property
   * @param {Object} obj
   * @param {String} property
   * @returns {String|Undefined} prefixed
   */
  function prefixed(obj, property) {
      var prefix, prop;
      var camelProp = property[0].toUpperCase() + property.slice(1);
  
      for (var i = 0, len = VENDOR_PREFIXES.length; i < len; i++) {
          prefix = VENDOR_PREFIXES[i];
          prop = (prefix) ? prefix + camelProp : property;
  
          if (prop in obj) {
              return prop;
          }
      }
      return undefined;
  }
  
  /**
   * get a unique id
   * @returns {number} uniqueId
   */
  var _uniqueId = 1;
  function uniqueId() {
      return _uniqueId++;
  }
  
  var MOBILE_REGEX = /mobile|tablet|ip(ad|hone|od)|android/i;
  
  var SUPPORT_TOUCH = ('ontouchstart' in window);
  var SUPPORT_POINTER_EVENTS = prefixed(window, 'PointerEvent') !== undefined;
  var SUPPORT_ONLY_TOUCH = SUPPORT_TOUCH && MOBILE_REGEX.test(navigator.userAgent);
  
  var INPUT_TYPE_TOUCH = 'touch';
  var INPUT_TYPE_PEN = 'pen';
  var INPUT_TYPE_MOUSE = 'mouse';
  var INPUT_TYPE_KINECT = 'kinect';
  
  var COMPUTE_INTERVAL = 25;
  
  var INPUT_START = 1;
  var INPUT_MOVE = 2;
  var INPUT_END = 4;
  var INPUT_CANCEL = 8;
  
  var DIRECTION_NONE = 1;
  var DIRECTION_LEFT = 2;
  var DIRECTION_RIGHT = 4;
  var DIRECTION_UP = 8;
  var DIRECTION_DOWN = 16;
  
  var DIRECTION_HORIZONTAL = DIRECTION_LEFT | DIRECTION_RIGHT;
  var DIRECTION_VERTICAL = DIRECTION_UP | DIRECTION_DOWN;
  var DIRECTION_ALL = DIRECTION_HORIZONTAL | DIRECTION_VERTICAL;
  
  var PROPS_XY = ['x', 'y'];
  var PROPS_CLIENT_XY = ['clientX', 'clientY'];
  
  /**
   * create new input type manager
   * @param {Manager} manager
   * @param {Function} callback
   * @returns {Input}
   * @constructor
   */
  function Input(manager, callback) {
      var self = this;
      this.manager = manager;
      this.callback = callback;
      this.element = manager.element;
      this.target = manager.options.inputTarget;
  
      // smaller wrapper around the handler, for the scope and the enabled state of the manager,
      // so when disabled the input events are completely bypassed.
      this.domHandler = function(ev) {
          if (boolOrFn(manager.options.enable, [manager])) {
              self.handler(ev);
          }
      };
  
      this.evEl && addEventListeners(this.element, this.evEl, this.domHandler);
      this.evTarget && addEventListeners(this.target, this.evTarget, this.domHandler);
      this.evWin && addEventListeners(window, this.evWin, this.domHandler);
  }
  
  Input.prototype = {
      /**
       * should handle the inputEvent data and trigger the callback
       * @virtual
       */
      handler: function() { },
  
      /**
       * unbind the events
       */
      destroy: function() {
          this.evEl && removeEventListeners(this.element, this.evEl, this.domHandler);
          this.evTarget && removeEventListeners(this.target, this.evTarget, this.domHandler);
          this.evWin && removeEventListeners(window, this.evWin, this.domHandler);
      }
  };
  
  /**
   * create new input type manager
   * @param {Hammer} manager
   * @returns {Input}
   */
  function createInputInstance(manager) {
      var Type;
      if (SUPPORT_POINTER_EVENTS) {
          Type = PointerEventInput;
      } else if (SUPPORT_ONLY_TOUCH) {
          Type = TouchInput;
      } else if (!SUPPORT_TOUCH) {
          Type = MouseInput;
      } else {
          Type = TouchMouseInput;
      }
      return new (Type)(manager, inputHandler);
  }
  
  /**
   * handle input events
   * @param {Manager} manager
   * @param {String} eventType
   * @param {Object} input
   */
  function inputHandler(manager, eventType, input) {
      var pointersLen = input.pointers.length;
      var changedPointersLen = input.changedPointers.length;
      var isFirst = (eventType & INPUT_START && (pointersLen - changedPointersLen === 0));
      var isFinal = (eventType & (INPUT_END | INPUT_CANCEL) && (pointersLen - changedPointersLen === 0));
  
      input.isFirst = !!isFirst;
      input.isFinal = !!isFinal;
  
      if (isFirst) {
          manager.session = {};
      }
  
      // source event is the normalized value of the domEvents
      // like 'touchstart, mouseup, pointerdown'
      input.eventType = eventType;
  
      // compute scale, rotation etc
      computeInputData(manager, input);
  
      // emit secret event
      manager.emit('hammer.input', input);
  
      manager.recognize(input);
      manager.session.prevInput = input;
  }
  
  /**
   * extend the data with some usable properties like scale, rotate, velocity etc
   * @param {Object} manager
   * @param {Object} input
   */
  function computeInputData(manager, input) {
      var session = manager.session;
      var pointers = input.pointers;
      var pointersLength = pointers.length;
  
      // store the first input to calculate the distance and direction
      if (!session.firstInput) {
          session.firstInput = simpleCloneInputData(input);
      }
  
      // to compute scale and rotation we need to store the multiple touches
      if (pointersLength > 1 && !session.firstMultiple) {
          session.firstMultiple = simpleCloneInputData(input);
      } else if (pointersLength === 1) {
          session.firstMultiple = false;
      }
  
      var firstInput = session.firstInput;
      var firstMultiple = session.firstMultiple;
      var offsetCenter = firstMultiple ? firstMultiple.center : firstInput.center;
  
      var center = input.center = getCenter(pointers);
      input.timeStamp = now();
      input.deltaTime = input.timeStamp - firstInput.timeStamp;
  
      input.angle = getAngle(offsetCenter, center);
      input.distance = getDistance(offsetCenter, center);
  
      computeDeltaXY(session, input);
      input.offsetDirection = getDirection(input.deltaX, input.deltaY);
  
      input.scale = firstMultiple ? getScale(firstMultiple.pointers, pointers) : 1;
      input.rotation = firstMultiple ? getRotation(firstMultiple.pointers, pointers) : 0;
  
      computeIntervalInputData(session, input);
  
      // find the correct target
      var target = manager.element;
      if (hasParent(input.srcEvent.target, target)) {
          target = input.srcEvent.target;
      }
      input.target = target;
  }
  
  function computeDeltaXY(session, input) {
      var center = input.center;
      var offset = session.offsetDelta || {};
      var prevDelta = session.prevDelta || {};
      var prevInput = session.prevInput || {};
  
      if (input.eventType === INPUT_START || prevInput.eventType === INPUT_END) {
          prevDelta = session.prevDelta = {
              x: prevInput.deltaX || 0,
              y: prevInput.deltaY || 0
          };
  
          offset = session.offsetDelta = {
              x: center.x,
              y: center.y
          };
      }
  
      input.deltaX = prevDelta.x + (center.x - offset.x);
      input.deltaY = prevDelta.y + (center.y - offset.y);
  }
  
  /**
   * velocity is calculated every x ms
   * @param {Object} session
   * @param {Object} input
   */
  function computeIntervalInputData(session, input) {
      var last = session.lastInterval || input,
          deltaTime = input.timeStamp - last.timeStamp,
          velocity, velocityX, velocityY, direction;
  
      if (input.eventType != INPUT_CANCEL && (deltaTime > COMPUTE_INTERVAL || last.velocity === undefined)) {
          var deltaX = last.deltaX - input.deltaX;
          var deltaY = last.deltaY - input.deltaY;
  
          var v = getVelocity(deltaTime, deltaX, deltaY);
          velocityX = v.x;
          velocityY = v.y;
          velocity = (abs(v.x) > abs(v.y)) ? v.x : v.y;
          direction = getDirection(deltaX, deltaY);
  
          session.lastInterval = input;
      } else {
          // use latest velocity info if it doesn't overtake a minimum period
          velocity = last.velocity;
          velocityX = last.velocityX;
          velocityY = last.velocityY;
          direction = last.direction;
      }
  
      input.velocity = velocity;
      input.velocityX = velocityX;
      input.velocityY = velocityY;
      input.direction = direction;
  }
  
  /**
   * create a simple clone from the input used for storage of firstInput and firstMultiple
   * @param {Object} input
   * @returns {Object} clonedInputData
   */
  function simpleCloneInputData(input) {
      // make a simple copy of the pointers because we will get a reference if we don't
      // we only need clientXY for the calculations
      var pointers = [];
      for (var i = 0; i < input.pointers.length; i++) {
          pointers[i] = {
              clientX: round(input.pointers[i].clientX),
              clientY: round(input.pointers[i].clientY)
          };
      }
  
      return {
          timeStamp: now(),
          pointers: pointers,
          center: getCenter(pointers),
          deltaX: input.deltaX,
          deltaY: input.deltaY
      };
  }
  
  /**
   * get the center of all the pointers
   * @param {Array} pointers
   * @return {Object} center contains `x` and `y` properties
   */
  function getCenter(pointers) {
      var pointersLength = pointers.length;
  
      // no need to loop when only one touch
      if (pointersLength === 1) {
          return {
              x: round(pointers[0].clientX),
              y: round(pointers[0].clientY)
          };
      }
  
      var x = 0, y = 0;
      for (var i = 0; i < pointersLength; i++) {
          x += pointers[i].clientX;
          y += pointers[i].clientY;
      }
  
      return {
          x: round(x / pointersLength),
          y: round(y / pointersLength)
      };
  }
  
  /**
   * calculate the velocity between two points. unit is in px per ms.
   * @param {Number} deltaTime
   * @param {Number} x
   * @param {Number} y
   * @return {Object} velocity `x` and `y`
   */
  function getVelocity(deltaTime, x, y) {
      return {
          x: x / deltaTime || 0,
          y: y / deltaTime || 0
      };
  }
  
  /**
   * get the direction between two points
   * @param {Number} x
   * @param {Number} y
   * @return {Number} direction
   */
  function getDirection(x, y) {
      if (x === y) {
          return DIRECTION_NONE;
      }
  
      if (abs(x) >= abs(y)) {
          return x > 0 ? DIRECTION_LEFT : DIRECTION_RIGHT;
      }
      return y > 0 ? DIRECTION_UP : DIRECTION_DOWN;
  }
  
  /**
   * calculate the absolute distance between two points
   * @param {Object} p1 {x, y}
   * @param {Object} p2 {x, y}
   * @param {Array} [props] containing x and y keys
   * @return {Number} distance
   */
  function getDistance(p1, p2, props) {
      if (!props) {
          props = PROPS_XY;
      }
      var x = p2[props[0]] - p1[props[0]],
          y = p2[props[1]] - p1[props[1]];
  
      return Math.sqrt((x * x) + (y * y));
  }
  
  /**
   * calculate the angle between two coordinates
   * @param {Object} p1
   * @param {Object} p2
   * @param {Array} [props] containing x and y keys
   * @return {Number} angle
   */
  function getAngle(p1, p2, props) {
      if (!props) {
          props = PROPS_XY;
      }
      var x = p2[props[0]] - p1[props[0]],
          y = p2[props[1]] - p1[props[1]];
      return Math.atan2(y, x) * 180 / Math.PI;
  }
  
  /**
   * calculate the rotation degrees between two pointersets
   * @param {Array} start array of pointers
   * @param {Array} end array of pointers
   * @return {Number} rotation
   */
  function getRotation(start, end) {
      return getAngle(end[1], end[0], PROPS_CLIENT_XY) - getAngle(start[1], start[0], PROPS_CLIENT_XY);
  }
  
  /**
   * calculate the scale factor between two pointersets
   * no scale is 1, and goes down to 0 when pinched together, and bigger when pinched out
   * @param {Array} start array of pointers
   * @param {Array} end array of pointers
   * @return {Number} scale
   */
  function getScale(start, end) {
      return getDistance(end[0], end[1], PROPS_CLIENT_XY) / getDistance(start[0], start[1], PROPS_CLIENT_XY);
  }
  
  var MOUSE_INPUT_MAP = {
      mousedown: INPUT_START,
      mousemove: INPUT_MOVE,
      mouseup: INPUT_END
  };
  
  var MOUSE_ELEMENT_EVENTS = 'mousedown';
  var MOUSE_WINDOW_EVENTS = 'mousemove mouseup';
  
  /**
   * Mouse events input
   * @constructor
   * @extends Input
   */
  function MouseInput() {
      this.evEl = MOUSE_ELEMENT_EVENTS;
      this.evWin = MOUSE_WINDOW_EVENTS;
  
      this.allow = true; // used by Input.TouchMouse to disable mouse events
      this.pressed = false; // mousedown state
  
      Input.apply(this, arguments);
  }
  
  inherit(MouseInput, Input, {
      /**
       * handle mouse events
       * @param {Object} ev
       */
      handler: function MEhandler(ev) {
          var eventType = MOUSE_INPUT_MAP[ev.type];
  
          // on start we want to have the left mouse button down
          if (eventType & INPUT_START && ev.button === 0) {
              this.pressed = true;
          }
  
          if (eventType & INPUT_MOVE && ev.which !== 1) {
              eventType = INPUT_END;
          }
  
          // mouse must be down, and mouse events are allowed (see the TouchMouse input)
          if (!this.pressed || !this.allow) {
              return;
          }
  
          if (eventType & INPUT_END) {
              this.pressed = false;
          }
  
          this.callback(this.manager, eventType, {
              pointers: [ev],
              changedPointers: [ev],
              pointerType: INPUT_TYPE_MOUSE,
              srcEvent: ev
          });
      },
  });
  
  var POINTER_INPUT_MAP = {
      pointerdown: INPUT_START,
      pointermove: INPUT_MOVE,
      pointerup: INPUT_END,
      pointercancel: INPUT_CANCEL,
      pointerout: INPUT_CANCEL
  };
  
  // in IE10 the pointer types is defined as an enum
  var IE10_POINTER_TYPE_ENUM = {
      2: INPUT_TYPE_TOUCH,
      3: INPUT_TYPE_PEN,
      4: INPUT_TYPE_MOUSE,
      5: INPUT_TYPE_KINECT // see https://twitter.com/jacobrossi/status/480596438489890816
  };
  
  var POINTER_ELEMENT_EVENTS = 'pointerdown';
  var POINTER_WINDOW_EVENTS = 'pointermove pointerup pointercancel';
  
  // IE10 has prefixed support, and case-sensitive
  if (window.MSPointerEvent) {
      POINTER_ELEMENT_EVENTS = 'MSPointerDown';
      POINTER_WINDOW_EVENTS = 'MSPointerMove MSPointerUp MSPointerCancel';
  }
  
  /**
   * Pointer events input
   * @constructor
   * @extends Input
   */
  function PointerEventInput() {
      this.evEl = POINTER_ELEMENT_EVENTS;
      this.evWin = POINTER_WINDOW_EVENTS;
  
      Input.apply(this, arguments);
  
      this.store = (this.manager.session.pointerEvents = []);
  }
  
  inherit(PointerEventInput, Input, {
      /**
       * handle mouse events
       * @param {Object} ev
       */
      handler: function PEhandler(ev) {
          var store = this.store;
          var removePointer = false;
  
          var eventTypeNormalized = ev.type.toLowerCase().replace('ms', '');
          var eventType = POINTER_INPUT_MAP[eventTypeNormalized];
          var pointerType = IE10_POINTER_TYPE_ENUM[ev.pointerType] || ev.pointerType;
  
          var isTouch = (pointerType == INPUT_TYPE_TOUCH);
  
          // start and mouse must be down
          if (eventType & INPUT_START && (ev.button === 0 || isTouch)) {
              store.push(ev);
          } else if (eventType & (INPUT_END | INPUT_CANCEL)) {
              removePointer = true;
          }
  
          // get index of the event in the store
          // it not found, so the pointer hasn't been down (so it's probably a hover)
          var storeIndex = inArray(store, ev.pointerId, 'pointerId');
          if (storeIndex < 0) {
              return;
          }
  
          // update the event in the store
          store[storeIndex] = ev;
  
          this.callback(this.manager, eventType, {
              pointers: store,
              changedPointers: [ev],
              pointerType: pointerType,
              srcEvent: ev
          });
  
          if (removePointer) {
              // remove from the store
              store.splice(storeIndex, 1);
          }
      }
  });
  
  var TOUCH_INPUT_MAP = {
      touchstart: INPUT_START,
      touchmove: INPUT_MOVE,
      touchend: INPUT_END,
      touchcancel: INPUT_CANCEL
  };
  
  var TOUCH_TARGET_EVENTS = 'touchstart touchmove touchend touchcancel';
  
  /**
   * Touch events input
   * @constructor
   * @extends Input
   */
  function TouchInput() {
      this.evTarget = TOUCH_TARGET_EVENTS;
      this.targetIds = {};
  
      Input.apply(this, arguments);
  }
  
  inherit(TouchInput, Input, {
      /**
       * handle touch events
       * @param {Object} ev
       */
      handler: function TEhandler(ev) {
          var type = TOUCH_INPUT_MAP[ev.type];
          var touches = getTouches.call(this, ev, type);
          if (!touches) {
              return;
          }
  
          this.callback(this.manager, type, {
              pointers: touches[0],
              changedPointers: touches[1],
              pointerType: INPUT_TYPE_TOUCH,
              srcEvent: ev
          });
      }
  });
  
  /**
   * @this {TouchInput}
   * @param {Object} ev
   * @param {Number} type flag
   * @returns {undefined|Array} [all, changed]
   */
  function getTouches(ev, type) {
      var allTouches = toArray(ev.touches);
      var targetIds = this.targetIds;
  
      // when there is only one touch, the process can be simplified
      if (type & (INPUT_START | INPUT_MOVE) && allTouches.length === 1) {
          targetIds[allTouches[0].identifier] = true;
          return [allTouches, allTouches];
      }
  
      var i, len;
      var targetTouches = toArray(ev.targetTouches);
      var changedTouches = toArray(ev.changedTouches);
      var changedTargetTouches = [];
  
      // collect touches
      if (type === INPUT_START) {
          for (i = 0, len = targetTouches.length; i < len; i++) {
              targetIds[targetTouches[i].identifier] = true;
          }
      }
  
      // filter changed touches to only contain touches that exist in the collected target ids
      for (i = 0, len = changedTouches.length; i < len; i++) {
          if (targetIds[changedTouches[i].identifier]) {
              changedTargetTouches.push(changedTouches[i]);
          }
  
          // cleanup removed touches
          if (type & (INPUT_END | INPUT_CANCEL)) {
              delete targetIds[changedTouches[i].identifier];
          }
      }
  
      if (!changedTargetTouches.length) {
          return;
      }
  
      return [
          // merge targetTouches with changedTargetTouches so it contains ALL touches, including 'end' and 'cancel'
          uniqueArray(targetTouches.concat(changedTargetTouches), 'identifier', true),
          changedTargetTouches
      ];
  }
  
  /**
   * Combined touch and mouse input
   *
   * Touch has a higher priority then mouse, and while touching no mouse events are allowed.
   * This because touch devices also emit mouse events while doing a touch.
   *
   * @constructor
   * @extends Input
   */
  function TouchMouseInput() {
      Input.apply(this, arguments);
  
      var handler = bindFn(this.handler, this);
      this.touch = new TouchInput(this.manager, handler);
      this.mouse = new MouseInput(this.manager, handler);
  }
  
  inherit(TouchMouseInput, Input, {
      /**
       * handle mouse and touch events
       * @param {Hammer} manager
       * @param {String} inputEvent
       * @param {Object} inputData
       */
      handler: function TMEhandler(manager, inputEvent, inputData) {
          var isTouch = (inputData.pointerType == INPUT_TYPE_TOUCH),
              isMouse = (inputData.pointerType == INPUT_TYPE_MOUSE);
  
          // when we're in a touch event, so  block all upcoming mouse events
          // most mobile browser also emit mouseevents, right after touchstart
          if (isTouch) {
              this.mouse.allow = false;
          } else if (isMouse && !this.mouse.allow) {
              return;
          }
  
          // reset the allowMouse when we're done
          if (inputEvent & (INPUT_END | INPUT_CANCEL)) {
              this.mouse.allow = true;
          }
  
          this.callback(manager, inputEvent, inputData);
      },
  
      /**
       * remove the event listeners
       */
      destroy: function destroy() {
          this.touch.destroy();
          this.mouse.destroy();
      }
  });
  
  var PREFIXED_TOUCH_ACTION = prefixed(TEST_ELEMENT.style, 'touchAction');
  var NATIVE_TOUCH_ACTION = PREFIXED_TOUCH_ACTION !== undefined;
  
  // magical touchAction value
  var TOUCH_ACTION_COMPUTE = 'compute';
  var TOUCH_ACTION_AUTO = 'auto';
  var TOUCH_ACTION_MANIPULATION = 'manipulation'; // not implemented
  var TOUCH_ACTION_NONE = 'none';
  var TOUCH_ACTION_PAN_X = 'pan-x';
  var TOUCH_ACTION_PAN_Y = 'pan-y';
  
  /**
   * Touch Action
   * sets the touchAction property or uses the js alternative
   * @param {Manager} manager
   * @param {String} value
   * @constructor
   */
  function TouchAction(manager, value) {
      this.manager = manager;
      this.set(value);
  }
  
  TouchAction.prototype = {
      /**
       * set the touchAction value on the element or enable the polyfill
       * @param {String} value
       */
      set: function(value) {
          // find out the touch-action by the event handlers
          if (value == TOUCH_ACTION_COMPUTE) {
              value = this.compute();
          }
  
          if (NATIVE_TOUCH_ACTION) {
              this.manager.element.style[PREFIXED_TOUCH_ACTION] = value;
          }
          this.actions = value.toLowerCase().trim();
      },
  
      /**
       * just re-set the touchAction value
       */
      update: function() {
          this.set(this.manager.options.touchAction);
      },
  
      /**
       * compute the value for the touchAction property based on the recognizer's settings
       * @returns {String} value
       */
      compute: function() {
          var actions = [];
          each(this.manager.recognizers, function(recognizer) {
              if (boolOrFn(recognizer.options.enable, [recognizer])) {
                  actions = actions.concat(recognizer.getTouchAction());
              }
          });
          return cleanTouchActions(actions.join(' '));
      },
  
      /**
       * this method is called on each input cycle and provides the preventing of the browser behavior
       * @param {Object} input
       */
      preventDefaults: function(input) {
          // not needed with native support for the touchAction property
          if (NATIVE_TOUCH_ACTION) {
              return;
          }
  
          var srcEvent = input.srcEvent;
          var direction = input.offsetDirection;
  
          // if the touch action did prevented once this session
          if (this.manager.session.prevented) {
              srcEvent.preventDefault();
              return;
          }
  
          var actions = this.actions;
          var hasNone = inStr(actions, TOUCH_ACTION_NONE);
          var hasPanY = inStr(actions, TOUCH_ACTION_PAN_Y);
          var hasPanX = inStr(actions, TOUCH_ACTION_PAN_X);
  
          if (hasNone || (hasPanY && hasPanX) ||
              (hasPanY && direction & DIRECTION_HORIZONTAL) ||
              (hasPanX && direction & DIRECTION_VERTICAL)) {
              return this.preventSrc(srcEvent);
          }
      },
  
      /**
       * call preventDefault to prevent the browser's default behavior (scrolling in most cases)
       * @param {Object} srcEvent
       */
      preventSrc: function(srcEvent) {
          this.manager.session.prevented = true;
          srcEvent.preventDefault();
      }
  };
  
  /**
   * when the touchActions are collected they are not a valid value, so we need to clean things up. *
   * @param {String} actions
   * @returns {*}
   */
  function cleanTouchActions(actions) {
      // none
      if (inStr(actions, TOUCH_ACTION_NONE)) {
          return TOUCH_ACTION_NONE;
      }
  
      var hasPanX = inStr(actions, TOUCH_ACTION_PAN_X);
      var hasPanY = inStr(actions, TOUCH_ACTION_PAN_Y);
  
      // pan-x and pan-y can be combined
      if (hasPanX && hasPanY) {
          return TOUCH_ACTION_PAN_X + ' ' + TOUCH_ACTION_PAN_Y;
      }
  
      // pan-x OR pan-y
      if (hasPanX || hasPanY) {
          return hasPanX ? TOUCH_ACTION_PAN_X : TOUCH_ACTION_PAN_Y;
      }
  
      // manipulation
      if (inStr(actions, TOUCH_ACTION_MANIPULATION)) {
          return TOUCH_ACTION_MANIPULATION;
      }
  
      return TOUCH_ACTION_AUTO;
  }
  
  /**
   * Recognizer flow explained; *
   * All recognizers have the initial state of POSSIBLE when a input session starts.
   * The definition of a input session is from the first input until the last input, with all it's movement in it. *
   * Example session for mouse-input: mousedown -> mousemove -> mouseup
   *
   * On each recognizing cycle (see Manager.recognize) the .recognize() method is executed
   * which determines with state it should be.
   *
   * If the recognizer has the state FAILED, CANCELLED or RECOGNIZED (equals ENDED), it is reset to
   * POSSIBLE to give it another change on the next cycle.
   *
   *               Possible
   *                  |
   *            +-----+---------------+
   *            |                     |
   *      +-----+-----+               |
   *      |           |               |
   *   Failed      Cancelled          |
   *                          +-------+------+
   *                          |              |
   *                      Recognized       Began
   *                                         |
   *                                      Changed
   *                                         |
   *                                  Ended/Recognized
   */
  var STATE_POSSIBLE = 1;
  var STATE_BEGAN = 2;
  var STATE_CHANGED = 4;
  var STATE_ENDED = 8;
  var STATE_RECOGNIZED = STATE_ENDED;
  var STATE_CANCELLED = 16;
  var STATE_FAILED = 32;
  
  /**
   * Recognizer
   * Every recognizer needs to extend from this class.
   * @constructor
   * @param {Object} options
   */
  function Recognizer(options) {
      this.id = uniqueId();
  
      this.manager = null;
      this.options = merge(options || {}, this.defaults);
  
      // default is enable true
      this.options.enable = ifUndefined(this.options.enable, true);
  
      this.state = STATE_POSSIBLE;
  
      this.simultaneous = {};
      this.requireFail = [];
  }
  
  Recognizer.prototype = {
      /**
       * @virtual
       * @type {Object}
       */
      defaults: {},
  
      /**
       * set options
       * @param {Object} options
       * @return {Recognizer}
       */
      set: function(options) {
          extend(this.options, options);
  
          // also update the touchAction, in case something changed about the directions/enabled state
          this.manager && this.manager.touchAction.update();
          return this;
      },
  
      /**
       * recognize simultaneous with an other recognizer.
       * @param {Recognizer} otherRecognizer
       * @returns {Recognizer} this
       */
      recognizeWith: function(otherRecognizer) {
          if (invokeArrayArg(otherRecognizer, 'recognizeWith', this)) {
              return this;
          }
  
          var simultaneous = this.simultaneous;
          otherRecognizer = getRecognizerByNameIfManager(otherRecognizer, this);
          if (!simultaneous[otherRecognizer.id]) {
              simultaneous[otherRecognizer.id] = otherRecognizer;
              otherRecognizer.recognizeWith(this);
          }
          return this;
      },
  
      /**
       * drop the simultaneous link. it doesnt remove the link on the other recognizer.
       * @param {Recognizer} otherRecognizer
       * @returns {Recognizer} this
       */
      dropRecognizeWith: function(otherRecognizer) {
          if (invokeArrayArg(otherRecognizer, 'dropRecognizeWith', this)) {
              return this;
          }
  
          otherRecognizer = getRecognizerByNameIfManager(otherRecognizer, this);
          delete this.simultaneous[otherRecognizer.id];
          return this;
      },
  
      /**
       * recognizer can only run when an other is failing
       * @param {Recognizer} otherRecognizer
       * @returns {Recognizer} this
       */
      requireFailure: function(otherRecognizer) {
          if (invokeArrayArg(otherRecognizer, 'requireFailure', this)) {
              return this;
          }
  
          var requireFail = this.requireFail;
          otherRecognizer = getRecognizerByNameIfManager(otherRecognizer, this);
          if (inArray(requireFail, otherRecognizer) === -1) {
              requireFail.push(otherRecognizer);
              otherRecognizer.requireFailure(this);
          }
          return this;
      },
  
      /**
       * drop the requireFailure link. it does not remove the link on the other recognizer.
       * @param {Recognizer} otherRecognizer
       * @returns {Recognizer} this
       */
      dropRequireFailure: function(otherRecognizer) {
          if (invokeArrayArg(otherRecognizer, 'dropRequireFailure', this)) {
              return this;
          }
  
          otherRecognizer = getRecognizerByNameIfManager(otherRecognizer, this);
          var index = inArray(this.requireFail, otherRecognizer);
          if (index > -1) {
              this.requireFail.splice(index, 1);
          }
          return this;
      },
  
      /**
       * has require failures boolean
       * @returns {boolean}
       */
      hasRequireFailures: function() {
          return this.requireFail.length > 0;
      },
  
      /**
       * if the recognizer can recognize simultaneous with an other recognizer
       * @param {Recognizer} otherRecognizer
       * @returns {Boolean}
       */
      canRecognizeWith: function(otherRecognizer) {
          return !!this.simultaneous[otherRecognizer.id];
      },
  
      /**
       * You should use `tryEmit` instead of `emit` directly to check
       * that all the needed recognizers has failed before emitting.
       * @param {Object} input
       */
      emit: function(input) {
          var self = this;
          var state = this.state;
  
          function emit(withState) {
              self.manager.emit(self.options.event + (withState ? stateStr(state) : ''), input);
          }
  
          // 'panstart' and 'panmove'
          if (state < STATE_ENDED) {
              emit(true);
          }
  
          emit(); // simple 'eventName' events
  
          // panend and pancancel
          if (state >= STATE_ENDED) {
              emit(true);
          }
      },
  
      /**
       * Check that all the require failure recognizers has failed,
       * if true, it emits a gesture event,
       * otherwise, setup the state to FAILED.
       * @param {Object} input
       */
      tryEmit: function(input) {
          if (this.canEmit()) {
              return this.emit(input);
          }
          // it's failing anyway
          this.state = STATE_FAILED;
      },
  
      /**
       * can we emit?
       * @returns {boolean}
       */
      canEmit: function() {
          for (var i = 0; i < this.requireFail.length; i++) {
              if (!(this.requireFail[i].state & (STATE_FAILED | STATE_POSSIBLE))) {
                  return false;
              }
          }
          return true;
      },
  
      /**
       * update the recognizer
       * @param {Object} inputData
       */
      recognize: function(inputData) {
          // make a new copy of the inputData
          // so we can change the inputData without messing up the other recognizers
          var inputDataClone = extend({}, inputData);
  
          // is is enabled and allow recognizing?
          if (!boolOrFn(this.options.enable, [this, inputDataClone])) {
              this.reset();
              this.state = STATE_FAILED;
              return;
          }
  
          // reset when we've reached the end
          if (this.state & (STATE_RECOGNIZED | STATE_CANCELLED | STATE_FAILED)) {
              this.state = STATE_POSSIBLE;
          }
  
          this.state = this.process(inputDataClone);
  
          // the recognizer has recognized a gesture
          // so trigger an event
          if (this.state & (STATE_BEGAN | STATE_CHANGED | STATE_ENDED | STATE_CANCELLED)) {
              this.tryEmit(inputDataClone);
          }
      },
  
      /**
       * return the state of the recognizer
       * the actual recognizing happens in this method
       * @virtual
       * @param {Object} inputData
       * @returns {Const} STATE
       */
      process: function(inputData) { }, // jshint ignore:line
  
      /**
       * return the preferred touch-action
       * @virtual
       * @returns {Array}
       */
      getTouchAction: function() { },
  
      /**
       * called when the gesture isn't allowed to recognize
       * like when another is being recognized or it is disabled
       * @virtual
       */
      reset: function() { }
  };
  
  /**
   * get a usable string, used as event postfix
   * @param {Const} state
   * @returns {String} state
   */
  function stateStr(state) {
      if (state & STATE_CANCELLED) {
          return 'cancel';
      } else if (state & STATE_ENDED) {
          return 'end';
      } else if (state & STATE_CHANGED) {
          return 'move';
      } else if (state & STATE_BEGAN) {
          return 'start';
      }
      return '';
  }
  
  /**
   * direction cons to string
   * @param {Const} direction
   * @returns {String}
   */
  function directionStr(direction) {
      if (direction == DIRECTION_DOWN) {
          return 'down';
      } else if (direction == DIRECTION_UP) {
          return 'up';
      } else if (direction == DIRECTION_LEFT) {
          return 'left';
      } else if (direction == DIRECTION_RIGHT) {
          return 'right';
      }
      return '';
  }
  
  /**
   * get a recognizer by name if it is bound to a manager
   * @param {Recognizer|String} otherRecognizer
   * @param {Recognizer} recognizer
   * @returns {Recognizer}
   */
  function getRecognizerByNameIfManager(otherRecognizer, recognizer) {
      var manager = recognizer.manager;
      if (manager) {
          return manager.get(otherRecognizer);
      }
      return otherRecognizer;
  }
  
  /**
   * This recognizer is just used as a base for the simple attribute recognizers.
   * @constructor
   * @extends Recognizer
   */
  function AttrRecognizer() {
      Recognizer.apply(this, arguments);
  }
  
  inherit(AttrRecognizer, Recognizer, {
      /**
       * @namespace
       * @memberof AttrRecognizer
       */
      defaults: {
          /**
           * @type {Number}
           * @default 1
           */
          pointers: 1
      },
  
      /**
       * Used to check if it the recognizer receives valid input, like input.distance > 10.
       * @memberof AttrRecognizer
       * @param {Object} input
       * @returns {Boolean} recognized
       */
      attrTest: function(input) {
          var optionPointers = this.options.pointers;
          return optionPointers === 0 || input.pointers.length === optionPointers;
      },
  
      /**
       * Process the input and return the state for the recognizer
       * @memberof AttrRecognizer
       * @param {Object} input
       * @returns {*} State
       */
      process: function(input) {
          var state = this.state;
          var eventType = input.eventType;
  
          var isRecognized = state & (STATE_BEGAN | STATE_CHANGED);
          var isValid = this.attrTest(input);
  
          // on cancel input and we've recognized before, return STATE_CANCELLED
          if (isRecognized && (eventType & INPUT_CANCEL || !isValid)) {
              return state | STATE_CANCELLED;
          } else if (isRecognized || isValid) {
              if (eventType & INPUT_END) {
                  return state | STATE_ENDED;
              } else if (!(state & STATE_BEGAN)) {
                  return STATE_BEGAN;
              }
              return state | STATE_CHANGED;
          }
          return STATE_FAILED;
      }
  });
  
  /**
   * Pan
   * Recognized when the pointer is down and moved in the allowed direction.
   * @constructor
   * @extends AttrRecognizer
   */
  function PanRecognizer() {
      AttrRecognizer.apply(this, arguments);
  
      this.pX = null;
      this.pY = null;
  }
  
  inherit(PanRecognizer, AttrRecognizer, {
      /**
       * @namespace
       * @memberof PanRecognizer
       */
      defaults: {
          event: 'pan',
          threshold: 10,
          pointers: 1,
          direction: DIRECTION_ALL
      },
  
      getTouchAction: function() {
          var direction = this.options.direction;
  
          if (direction === DIRECTION_ALL) {
              return [TOUCH_ACTION_NONE];
          }
  
          var actions = [];
          if (direction & DIRECTION_HORIZONTAL) {
              actions.push(TOUCH_ACTION_PAN_Y);
          }
          if (direction & DIRECTION_VERTICAL) {
              actions.push(TOUCH_ACTION_PAN_X);
          }
          return actions;
      },
  
      directionTest: function(input) {
          var options = this.options;
          var hasMoved = true;
          var distance = input.distance;
          var direction = input.direction;
          var x = input.deltaX;
          var y = input.deltaY;
  
          // lock to axis?
          if (!(direction & options.direction)) {
              if (options.direction & DIRECTION_HORIZONTAL) {
                  direction = (x === 0) ? DIRECTION_NONE : (x < 0) ? DIRECTION_LEFT : DIRECTION_RIGHT;
                  hasMoved = x != this.pX;
                  distance = Math.abs(input.deltaX);
              } else {
                  direction = (y === 0) ? DIRECTION_NONE : (y < 0) ? DIRECTION_UP : DIRECTION_DOWN;
                  hasMoved = y != this.pY;
                  distance = Math.abs(input.deltaY);
              }
          }
          input.direction = direction;
          return hasMoved && distance > options.threshold && direction & options.direction;
      },
  
      attrTest: function(input) {
          return AttrRecognizer.prototype.attrTest.call(this, input) &&
              (this.state & STATE_BEGAN || (!(this.state & STATE_BEGAN) && this.directionTest(input)));
      },
  
      emit: function(input) {
          this.pX = input.deltaX;
          this.pY = input.deltaY;
  
          var direction = directionStr(input.direction);
          if (direction) {
              this.manager.emit(this.options.event + direction, input);
          }
  
          this._super.emit.call(this, input);
      }
  });
  
  /**
   * Pinch
   * Recognized when two or more pointers are moving toward (zoom-in) or away from each other (zoom-out).
   * @constructor
   * @extends AttrRecognizer
   */
  function PinchRecognizer() {
      AttrRecognizer.apply(this, arguments);
  }
  
  inherit(PinchRecognizer, AttrRecognizer, {
      /**
       * @namespace
       * @memberof PinchRecognizer
       */
      defaults: {
          event: 'pinch',
          threshold: 0,
          pointers: 2
      },
  
      getTouchAction: function() {
          return [TOUCH_ACTION_NONE];
      },
  
      attrTest: function(input) {
          return this._super.attrTest.call(this, input) &&
              (Math.abs(input.scale - 1) > this.options.threshold || this.state & STATE_BEGAN);
      },
  
      emit: function(input) {
          this._super.emit.call(this, input);
          if (input.scale !== 1) {
              var inOut = input.scale < 1 ? 'in' : 'out';
              this.manager.emit(this.options.event + inOut, input);
          }
      }
  });
  
  /**
   * Press
   * Recognized when the pointer is down for x ms without any movement.
   * @constructor
   * @extends Recognizer
   */
  function PressRecognizer() {
      Recognizer.apply(this, arguments);
  
      this._timer = null;
      this._input = null;
  }
  
  inherit(PressRecognizer, Recognizer, {
      /**
       * @namespace
       * @memberof PressRecognizer
       */
      defaults: {
          event: 'press',
          pointers: 1,
          time: 500, // minimal time of the pointer to be pressed
          threshold: 5 // a minimal movement is ok, but keep it low
      },
  
      getTouchAction: function() {
          return [TOUCH_ACTION_AUTO];
      },
  
      process: function(input) {
          var options = this.options;
          var validPointers = input.pointers.length === options.pointers;
          var validMovement = input.distance < options.threshold;
          var validTime = input.deltaTime > options.time;
  
          this._input = input;
  
          // we only allow little movement
          // and we've reached an end event, so a tap is possible
          if (!validMovement || !validPointers || (input.eventType & (INPUT_END | INPUT_CANCEL) && !validTime)) {
              this.reset();
          } else if (input.eventType & INPUT_START) {
              this.reset();
              this._timer = setTimeoutContext(function() {
                  this.state = STATE_RECOGNIZED;
                  this.tryEmit();
              }, options.time, this);
          } else if (input.eventType & INPUT_END) {
              return STATE_RECOGNIZED;
          }
          return STATE_FAILED;
      },
  
      reset: function() {
          clearTimeout(this._timer);
      },
  
      emit: function(input) {
          if (this.state !== STATE_RECOGNIZED) {
              return;
          }
  
          if (input && (input.eventType & INPUT_END)) {
              this.manager.emit(this.options.event + 'up', input);
          } else {
              this._input.timeStamp = now();
              this.manager.emit(this.options.event, this._input);
          }
      }
  });
  
  /**
   * Rotate
   * Recognized when two or more pointer are moving in a circular motion.
   * @constructor
   * @extends AttrRecognizer
   */
  function RotateRecognizer() {
      AttrRecognizer.apply(this, arguments);
  }
  
  inherit(RotateRecognizer, AttrRecognizer, {
      /**
       * @namespace
       * @memberof RotateRecognizer
       */
      defaults: {
          event: 'rotate',
          threshold: 0,
          pointers: 2
      },
  
      getTouchAction: function() {
          return [TOUCH_ACTION_NONE];
      },
  
      attrTest: function(input) {
          return this._super.attrTest.call(this, input) &&
              (Math.abs(input.rotation) > this.options.threshold || this.state & STATE_BEGAN);
      }
  });
  
  /**
   * Swipe
   * Recognized when the pointer is moving fast (velocity), with enough distance in the allowed direction.
   * @constructor
   * @extends AttrRecognizer
   */
  function SwipeRecognizer() {
      AttrRecognizer.apply(this, arguments);
  }
  
  inherit(SwipeRecognizer, AttrRecognizer, {
      /**
       * @namespace
       * @memberof SwipeRecognizer
       */
      defaults: {
          event: 'swipe',
          threshold: 10,
          velocity: 0.65,
          direction: DIRECTION_HORIZONTAL | DIRECTION_VERTICAL,
          pointers: 1
      },
  
      getTouchAction: function() {
          return PanRecognizer.prototype.getTouchAction.call(this);
      },
  
      attrTest: function(input) {
          var direction = this.options.direction;
          var velocity;
  
          if (direction & (DIRECTION_HORIZONTAL | DIRECTION_VERTICAL)) {
              velocity = input.velocity;
          } else if (direction & DIRECTION_HORIZONTAL) {
              velocity = input.velocityX;
          } else if (direction & DIRECTION_VERTICAL) {
              velocity = input.velocityY;
          }
  
          return this._super.attrTest.call(this, input) &&
              direction & input.direction &&
              abs(velocity) > this.options.velocity && input.eventType & INPUT_END;
      },
  
      emit: function(input) {
          var direction = directionStr(input.direction);
          if (direction) {
              this.manager.emit(this.options.event + direction, input);
          }
  
          this.manager.emit(this.options.event, input);
      }
  });
  
  /**
   * A tap is ecognized when the pointer is doing a small tap/click. Multiple taps are recognized if they occur
   * between the given interval and position. The delay option can be used to recognize multi-taps without firing
   * a single tap.
   *
   * The eventData from the emitted event contains the property `tapCount`, which contains the amount of
   * multi-taps being recognized.
   * @constructor
   * @extends Recognizer
   */
  function TapRecognizer() {
      Recognizer.apply(this, arguments);
  
      // previous time and center,
      // used for tap counting
      this.pTime = false;
      this.pCenter = false;
  
      this._timer = null;
      this._input = null;
      this.count = 0;
  }
  
  inherit(TapRecognizer, Recognizer, {
      /**
       * @namespace
       * @memberof PinchRecognizer
       */
      defaults: {
          event: 'tap',
          pointers: 1,
          taps: 1,
          interval: 300, // max time between the multi-tap taps
          time: 250, // max time of the pointer to be down (like finger on the screen)
          threshold: 2, // a minimal movement is ok, but keep it low
          posThreshold: 10 // a multi-tap can be a bit off the initial position
      },
  
      getTouchAction: function() {
          return [TOUCH_ACTION_MANIPULATION];
      },
  
      process: function(input) {
          var options = this.options;
  
          var validPointers = input.pointers.length === options.pointers;
          var validMovement = input.distance < options.threshold;
          var validTouchTime = input.deltaTime < options.time;
  
          this.reset();
  
          if ((input.eventType & INPUT_START) && (this.count === 0)) {
              return this.failTimeout();
          }
  
          // we only allow little movement
          // and we've reached an end event, so a tap is possible
          if (validMovement && validTouchTime && validPointers) {
              if (input.eventType != INPUT_END) {
                  return this.failTimeout();
              }
  
              var validInterval = this.pTime ? (input.timeStamp - this.pTime < options.interval) : true;
              var validMultiTap = !this.pCenter || getDistance(this.pCenter, input.center) < options.posThreshold;
  
              this.pTime = input.timeStamp;
              this.pCenter = input.center;
  
              if (!validMultiTap || !validInterval) {
                  this.count = 1;
              } else {
                  this.count += 1;
              }
  
              this._input = input;
  
              // if tap count matches we have recognized it,
              // else it has began recognizing...
              var tapCount = this.count % options.taps;
              if (tapCount === 0) {
                  // no failing requirements, immediately trigger the tap event
                  // or wait as long as the multitap interval to trigger
                  if (!this.hasRequireFailures()) {
                      return STATE_RECOGNIZED;
                  } else {
                      this._timer = setTimeoutContext(function() {
                          this.state = STATE_RECOGNIZED;
                          this.tryEmit();
                      }, options.interval, this);
                      return STATE_BEGAN;
                  }
              }
          }
          return STATE_FAILED;
      },
  
      failTimeout: function() {
          this._timer = setTimeoutContext(function() {
              this.state = STATE_FAILED;
          }, this.options.interval, this);
          return STATE_FAILED;
      },
  
      reset: function() {
          clearTimeout(this._timer);
      },
  
      emit: function() {
          if (this.state == STATE_RECOGNIZED ) {
              this._input.tapCount = this.count;
              this.manager.emit(this.options.event, this._input);
          }
      }
  });
  
  /**
   * Simple way to create an manager with a default set of recognizers.
   * @param {HTMLElement} element
   * @param {Object} [options]
   * @constructor
   */
  function Hammer(element, options) {
      options = options || {};
      options.recognizers = ifUndefined(options.recognizers, Hammer.defaults.preset);
      return new Manager(element, options);
  }
  
  /**
   * @const {string}
   */
  Hammer.VERSION = '2.0.2';
  
  /**
   * default settings
   * @namespace
   */
  Hammer.defaults = {
      /**
       * set if DOM events are being triggered.
       * But this is slower and unused by simple implementations, so disabled by default.
       * @type {Boolean}
       * @default false
       */
      domEvents: false,
  
      /**
       * The value for the touchAction property/fallback.
       * When set to `compute` it will magically set the correct value based on the added recognizers.
       * @type {String}
       * @default compute
       */
      touchAction: TOUCH_ACTION_COMPUTE,
  
      /**
       * EXPERIMENTAL FEATURE
       * Change the parent input target element.
       * If Null, then it is being set the to main element.
       * @type {Null|EventTarget}
       * @default null
       */
      inputTarget: null,
  
      /**
       * @type {Boolean}
       * @default true
       */
      enable: true,
  
      /**
       * Default recognizer setup when calling `Hammer()`
       * When creating a new Manager these will be skipped.
       * @type {Array}
       */
      preset: [
          // RecognizerClass, options, [recognizeWith, ...], [requireFailure, ...]
          [RotateRecognizer, { enable: false }],
          [PinchRecognizer, { enable: false }, ['rotate']],
          [SwipeRecognizer,{ direction: DIRECTION_HORIZONTAL }],
          [PanRecognizer, { direction: DIRECTION_HORIZONTAL }, ['swipe']],
          [TapRecognizer],
          [TapRecognizer, { event: 'doubletap', taps: 2 }, ['tap']],
          [PressRecognizer]
      ],
  
      /**
       * Some CSS properties can be used to improve the working of Hammer.
       * Add them to this method and they will be set when creating a new Manager.
       * @namespace
       */
      cssProps: {
          /**
           * Disables text selection to improve the dragging gesture. Mainly for desktop browsers.
           * @type {String}
           * @default 'none'
           */
          userSelect: 'none',
  
          /**
           * Disable the Windows Phone grippers when pressing an element.
           * @type {String}
           * @default 'none'
           */
          touchSelect: 'none',
  
          /**
           * Disables the default callout shown when you touch and hold a touch target.
           * On iOS, when you touch and hold a touch target such as a link, Safari displays
           * a callout containing information about the link. This property allows you to disable that callout.
           * @type {String}
           * @default 'none'
           */
          touchCallout: 'none',
  
          /**
           * Specifies whether zooming is enabled. Used by IE10>
           * @type {String}
           * @default 'none'
           */
          contentZooming: 'none',
  
          /**
           * Specifies that an entire element should be draggable instead of its contents. Mainly for desktop browsers.
           * @type {String}
           * @default 'none'
           */
          userDrag: 'none',
  
          /**
           * Overrides the highlight color shown when the user taps a link or a JavaScript
           * clickable element in iOS. This property obeys the alpha value, if specified.
           * @type {String}
           * @default 'rgba(0,0,0,0)'
           */
          tapHighlightColor: 'rgba(0,0,0,0)'
      }
  };
  
  var STOP = 1;
  var FORCED_STOP = 2;
  
  /**
   * Manager
   * @param {HTMLElement} element
   * @param {Object} [options]
   * @constructor
   */
  function Manager(element, options) {
      options = options || {};
  
      this.options = merge(options, Hammer.defaults);
      this.options.inputTarget = this.options.inputTarget || element;
  
      this.handlers = {};
      this.session = {};
      this.recognizers = [];
  
      this.element = element;
      this.input = createInputInstance(this);
      this.touchAction = new TouchAction(this, this.options.touchAction);
  
      toggleCssProps(this, true);
  
      each(options.recognizers, function(item) {
          var recognizer = this.add(new (item[0])(item[1]));
          item[2] && recognizer.recognizeWith(item[2]);
          item[3] && recognizer.requireFailure(item[2]);
      }, this);
  }
  
  Manager.prototype = {
      /**
       * set options
       * @param {Object} options
       * @returns {Manager}
       */
      set: function(options) {
          extend(this.options, options);
          return this;
      },
  
      /**
       * stop recognizing for this session.
       * This session will be discarded, when a new [input]start event is fired.
       * When forced, the recognizer cycle is stopped immediately.
       * @param {Boolean} [force]
       */
      stop: function(force) {
          this.session.stopped = force ? FORCED_STOP : STOP;
      },
  
      /**
       * run the recognizers!
       * called by the inputHandler function on every movement of the pointers (touches)
       * it walks through all the recognizers and tries to detect the gesture that is being made
       * @param {Object} inputData
       */
      recognize: function(inputData) {
          var session = this.session;
          if (session.stopped) {
              return;
          }
  
          // run the touch-action polyfill
          this.touchAction.preventDefaults(inputData);
  
          var recognizer;
          var recognizers = this.recognizers;
  
          // this holds the recognizer that is being recognized.
          // so the recognizer's state needs to be BEGAN, CHANGED, ENDED or RECOGNIZED
          // if no recognizer is detecting a thing, it is set to `null`
          var curRecognizer = session.curRecognizer;
  
          // reset when the last recognizer is recognized
          // or when we're in a new session
          if (!curRecognizer || (curRecognizer && curRecognizer.state & STATE_RECOGNIZED)) {
              curRecognizer = session.curRecognizer = null;
          }
  
          for (var i = 0, len = recognizers.length; i < len; i++) {
              recognizer = recognizers[i];
  
              // find out if we are allowed try to recognize the input for this one.
              // 1.   allow if the session is NOT forced stopped (see the .stop() method)
              // 2.   allow if we still haven't recognized a gesture in this session, or the this recognizer is the one
              //      that is being recognized.
              // 3.   allow if the recognizer is allowed to run simultaneous with the current recognized recognizer.
              //      this can be setup with the `recognizeWith()` method on the recognizer.
              if (session.stopped !== FORCED_STOP && ( // 1
                      !curRecognizer || recognizer == curRecognizer || // 2
                      recognizer.canRecognizeWith(curRecognizer))) { // 3
                  recognizer.recognize(inputData);
              } else {
                  recognizer.reset();
              }
  
              // if the recognizer has been recognizing the input as a valid gesture, we want to store this one as the
              // current active recognizer. but only if we don't already have an active recognizer
              if (!curRecognizer && recognizer.state & (STATE_BEGAN | STATE_CHANGED | STATE_ENDED)) {
                  curRecognizer = session.curRecognizer = recognizer;
              }
          }
      },
  
      /**
       * get a recognizer by its event name.
       * @param {Recognizer|String} recognizer
       * @returns {Recognizer|Null}
       */
      get: function(recognizer) {
          if (recognizer instanceof Recognizer) {
              return recognizer;
          }
  
          var recognizers = this.recognizers;
          for (var i = 0; i < recognizers.length; i++) {
              if (recognizers[i].options.event == recognizer) {
                  return recognizers[i];
              }
          }
          return null;
      },
  
      /**
       * add a recognizer to the manager
       * existing recognizers with the same event name will be removed
       * @param {Recognizer} recognizer
       * @returns {Recognizer|Manager}
       */
      add: function(recognizer) {
          if (invokeArrayArg(recognizer, 'add', this)) {
              return this;
          }
  
          // remove existing
          var existing = this.get(recognizer.options.event);
          if (existing) {
              this.remove(existing);
          }
  
          this.recognizers.push(recognizer);
          recognizer.manager = this;
  
          this.touchAction.update();
          return recognizer;
      },
  
      /**
       * remove a recognizer by name or instance
       * @param {Recognizer|String} recognizer
       * @returns {Manager}
       */
      remove: function(recognizer) {
          if (invokeArrayArg(recognizer, 'remove', this)) {
              return this;
          }
  
          var recognizers = this.recognizers;
          recognizer = this.get(recognizer);
          recognizers.splice(inArray(recognizers, recognizer), 1);
  
          this.touchAction.update();
          return this;
      },
  
      /**
       * bind event
       * @param {String} events
       * @param {Function} handler
       * @returns {EventEmitter} this
       */
      on: function(events, handler) {
          var handlers = this.handlers;
          each(splitStr(events), function(event) {
              handlers[event] = handlers[event] || [];
              handlers[event].push(handler);
          });
          return this;
      },
  
      /**
       * unbind event, leave emit blank to remove all handlers
       * @param {String} events
       * @param {Function} [handler]
       * @returns {EventEmitter} this
       */
      off: function(events, handler) {
          var handlers = this.handlers;
          each(splitStr(events), function(event) {
              if (!handler) {
                  delete handlers[event];
              } else {
                  handlers[event].splice(inArray(handlers[event], handler), 1);
              }
          });
          return this;
      },
  
      /**
       * emit event to the listeners
       * @param {String} event
       * @param {Object} data
       */
      emit: function(event, data) {
          // we also want to trigger dom events
          if (this.options.domEvents) {
              triggerDomEvent(event, data);
          }
  
          // no handlers, so skip it all
          var handlers = this.handlers[event] && this.handlers[event].slice();
          if (!handlers || !handlers.length) {
              return;
          }
  
          data.type = event;
          data.preventDefault = function() {
              data.srcEvent.preventDefault();
          };
  
          for (var i = 0, len = handlers.length; i < len; i++) {
              handlers[i](data);
          }
      },
  
      /**
       * destroy the manager and unbinds all events
       * it doesn't unbind dom events, that is the user own responsibility
       */
      destroy: function() {
          this.element && toggleCssProps(this, false);
  
          this.handlers = {};
          this.session = {};
          this.input.destroy();
          this.element = null;
      }
  };
  
  /**
   * add/remove the css properties as defined in manager.options.cssProps
   * @param {Manager} manager
   * @param {Boolean} add
   */
  function toggleCssProps(manager, add) {
      var element = manager.element;
      each(manager.options.cssProps, function(value, name) {
          element.style[prefixed(element.style, name)] = add ? value : '';
      });
  }
  
  /**
   * trigger dom event
   * @param {String} event
   * @param {Object} data
   */
  function triggerDomEvent(event, data) {
      var gestureEvent = document.createEvent('Event');
      gestureEvent.initEvent(event, true, true);
      gestureEvent.gesture = data;
      data.target.dispatchEvent(gestureEvent);
  }
  
  extend(Hammer, {
      INPUT_START: INPUT_START,
      INPUT_MOVE: INPUT_MOVE,
      INPUT_END: INPUT_END,
      INPUT_CANCEL: INPUT_CANCEL,
  
      STATE_POSSIBLE: STATE_POSSIBLE,
      STATE_BEGAN: STATE_BEGAN,
      STATE_CHANGED: STATE_CHANGED,
      STATE_ENDED: STATE_ENDED,
      STATE_RECOGNIZED: STATE_RECOGNIZED,
      STATE_CANCELLED: STATE_CANCELLED,
      STATE_FAILED: STATE_FAILED,
  
      DIRECTION_NONE: DIRECTION_NONE,
      DIRECTION_LEFT: DIRECTION_LEFT,
      DIRECTION_RIGHT: DIRECTION_RIGHT,
      DIRECTION_UP: DIRECTION_UP,
      DIRECTION_DOWN: DIRECTION_DOWN,
      DIRECTION_HORIZONTAL: DIRECTION_HORIZONTAL,
      DIRECTION_VERTICAL: DIRECTION_VERTICAL,
      DIRECTION_ALL: DIRECTION_ALL,
  
      Manager: Manager,
      Input: Input,
      TouchAction: TouchAction,
  
      Recognizer: Recognizer,
      AttrRecognizer: AttrRecognizer,
      Tap: TapRecognizer,
      Pan: PanRecognizer,
      Swipe: SwipeRecognizer,
      Pinch: PinchRecognizer,
      Rotate: RotateRecognizer,
      Press: PressRecognizer,
  
      on: addEventListeners,
      off: removeEventListeners,
      each: each,
      merge: merge,
      extend: extend,
      inherit: inherit,
      bindFn: bindFn,
      prefixed: prefixed
  });
  
  if (typeof define == TYPE_FUNCTION && define.amd) {
      define(function() {
          return Hammer;
      });
  } else if (typeof module != 'undefined' && module.exports) {
      module.exports = Hammer;
  } else {
      window[exportName] = Hammer;
  }
  
  })(window, document, 'Hammer');