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.init();
}
Input.prototype = {
/**
* should handle the inputEvent data and trigger the callback
* @virtual
*/
handler: function() { },
/**
* bind the events
*/
init: function() {
this.evEl && addEventListeners(this.element, this.evEl, this.domHandler);
this.evTarget && addEventListeners(this.target, this.evTarget, this.domHandler);
this.evWin && addEventListeners(getWindowForElement(this.element), this.evWin, this.domHandler);
},
/**
* 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(getWindowForElement(this.element), this.evWin, this.domHandler);
}
};
/**
* create new input type manager
* called by the Manager constructor
* @param {Hammer} manager
* @returns {Input}
*/
function createInputInstance(manager) {
var Type;
var inputClass = manager.options.inputClass;
if (inputClass) {
Type = inputClass;
} else 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);
var overallVelocity = getVelocity(input.deltaTime, input.deltaX, input.deltaY);
input.overallVelocityX = overallVelocity.x;
input.overallVelocityY = overallVelocity.y;
input.overallVelocity = (abs(overallVelocity.x) > abs(overallVelocity.y)) ? overallVelocity.x : overallVelocity.y;
input.scale = firstMultiple ? getScale(firstMultiple.pointers, pointers) : 1;
input.rotation = firstMultiple ? getRotation(firstMultiple.pointers, pointers) : 0;
input.maxPointers = !session.prevInput ? input.pointers.length : ((input.pointers.length >
session.prevInput.maxPointers) ? input.pointers.length : session.prevInput.maxPointers);
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 = input.deltaX - last.deltaX;
var deltaY = input.deltaY - last.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 = [];
var i = 0;
while (i < input.pointers.length) {
pointers[i] = {
clientX: round(input.pointers[i].clientX),
clientY: round(input.pointers[i].clientY)
};
i++;
}
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, i = 0;
while (i < pointersLength) {
x += pointers[i].clientX;
y += pointers[i].clientY;
i++;
}
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);
}