event.js

var Eventful = require("../mixin/Eventful");

exports.Dispatcher = Eventful;

var env = require("./env");

/**
 * 事件辅助类
 * @module zrender/core/event
 * @author Kener (@Kener-林峰, kener.linfeng@gmail.com)
 */
var isDomLevel2 = typeof window !== 'undefined' && !!window.addEventListener;
var MOUSE_EVENT_REG = /^(?:mouse|pointer|contextmenu|drag|drop)|click/;

function getBoundingClientRect(el) {
  // BlackBerry 5, iOS 3 (original iPhone) don't have getBoundingRect
  return el.getBoundingClientRect ? el.getBoundingClientRect() : {
    left: 0,
    top: 0
  };
} // `calculate` is optional, default false


function clientToLocal(el, e, out, calculate) {
  out = out || {}; // According to the W3C Working Draft, offsetX and offsetY should be relative
  // to the padding edge of the target element. The only browser using this convention
  // is IE. Webkit uses the border edge, Opera uses the content edge, and FireFox does
  // not support the properties.
  // (see http://www.jacklmoore.com/notes/mouse-position/)
  // In zr painter.dom, padding edge equals to border edge.
  // FIXME
  // When mousemove event triggered on ec tooltip, target is not zr painter.dom, and
  // offsetX/Y is relative to e.target, where the calculation of zrX/Y via offsetX/Y
  // is too complex. So css-transfrom dont support in this case temporarily.

  if (calculate || !env.canvasSupported) {
    defaultGetZrXY(el, e, out);
  } // Caution: In FireFox, layerX/layerY Mouse position relative to the closest positioned
  // ancestor element, so we should make sure el is positioned (e.g., not position:static).
  // BTW1, Webkit don't return the same results as FF in non-simple cases (like add
  // zoom-factor, overflow / opacity layers, transforms ...)
  // BTW2, (ev.offsetY || ev.pageY - $(ev.target).offset().top) is not correct in preserve-3d.
  // <https://bugs.jquery.com/ticket/8523#comment:14>
  // BTW3, In ff, offsetX/offsetY is always 0.
  else if (env.browser.firefox && e.layerX != null && e.layerX !== e.offsetX) {
      out.zrX = e.layerX;
      out.zrY = e.layerY;
    } // For IE6+, chrome, safari, opera. (When will ff support offsetX?)
    else if (e.offsetX != null) {
        out.zrX = e.offsetX;
        out.zrY = e.offsetY;
      } // For some other device, e.g., IOS safari.
      else {
          defaultGetZrXY(el, e, out);
        }

  return out;
}

function defaultGetZrXY(el, e, out) {
  // This well-known method below does not support css transform.
  var box = getBoundingClientRect(el);
  out.zrX = e.clientX - box.left;
  out.zrY = e.clientY - box.top;
}
/**
 * 如果存在第三方嵌入的一些dom触发的事件，或touch事件，需要转换一下事件坐标.
 * `calculate` is optional, default false.
 */


function normalizeEvent(el, e, calculate) {
  e = e || window.event;

  if (e.zrX != null) {
    return e;
  }

  var eventType = e.type;
  var isTouch = eventType && eventType.indexOf('touch') >= 0;

  if (!isTouch) {
    clientToLocal(el, e, e, calculate);
    e.zrDelta = e.wheelDelta ? e.wheelDelta / 120 : -(e.detail || 0) / 3;
  } else {
    var touch = eventType !== 'touchend' ? e.targetTouches[0] : e.changedTouches[0];
    touch && clientToLocal(el, touch, e, calculate);
  } // Add which for click: 1 === left; 2 === middle; 3 === right; otherwise: 0;
  // See jQuery: https://github.com/jquery/jquery/blob/master/src/event.js
  // If e.which has been defined, if may be readonly,
  // see: https://developer.mozilla.org/en-US/docs/Web/API/MouseEvent/which


  var button = e.button;

  if (e.which == null && button !== undefined && MOUSE_EVENT_REG.test(e.type)) {
    e.which = button & 1 ? 1 : button & 2 ? 3 : button & 4 ? 2 : 0;
  } // [Caution]: `e.which` from browser is not always reliable. For example,
  // when press left button and `mousemove (pointermove)` in Edge, the `e.which`
  // is 65536 and the `e.button` is -1. But the `mouseup (pointerup)` and
  // `mousedown (pointerdown)` is the same as Chrome does.


  return e;
}
/**
 * @param {HTMLElement} el
 * @param {string} name
 * @param {Function} handler
 */


function addEventListener(el, name, handler) {
  if (isDomLevel2) {
    // Reproduct the console warning:
    // [Violation] Added non-passive event listener to a scroll-blocking <some> event.
    // Consider marking event handler as 'passive' to make the page more responsive.
    // Just set console log level: verbose in chrome dev tool.
    // then the warning log will be printed when addEventListener called.
    // See https://github.com/WICG/EventListenerOptions/blob/gh-pages/explainer.md
    // We have not yet found a neat way to using passive. Because in zrender the dom event
    // listener delegate all of the upper events of element. Some of those events need
    // to prevent default. For example, the feature `preventDefaultMouseMove` of echarts.
    // Before passive can be adopted, these issues should be considered:
    // (1) Whether and how a zrender user specifies an event listener passive. And by default,
    // passive or not.
    // (2) How to tread that some zrender event listener is passive, and some is not. If
    // we use other way but not preventDefault of mousewheel and touchmove, browser
    // compatibility should be handled.
    // var opts = (env.passiveSupported && name === 'mousewheel')
    //     ? {passive: true}
    //     // By default, the third param of el.addEventListener is `capture: false`.
    //     : void 0;
    // el.addEventListener(name, handler /* , opts */);
    el.addEventListener(name, handler);
  } else {
    el.attachEvent('on' + name, handler);
  }
}

function removeEventListener(el, name, handler) {
  if (isDomLevel2) {
    el.removeEventListener(name, handler);
  } else {
    el.detachEvent('on' + name, handler);
  }
}
/**
 * preventDefault and stopPropagation.
 * Notice: do not do that in zrender. Upper application
 * do that if necessary.
 *
 * @memberOf module:zrender/core/event
 * @method
 * @param {Event} e : event对象
 */


var stop = isDomLevel2 ? function (e) {
  e.preventDefault();
  e.stopPropagation();
  e.cancelBubble = true;
} : function (e) {
  e.returnValue = false;
  e.cancelBubble = true;
};
/**
 * This method only works for mouseup and mousedown. The functionality is restricted
 * for fault tolerance, See the `e.which` compatibility above.
 *
 * @param {MouseEvent} e
 * @return {boolean}
 */

function isMiddleOrRightButtonOnMouseUpDown(e) {
  return e.which === 2 || e.which === 3;
}
/**
 * To be removed.
 * @deprecated
 */


function notLeftMouse(e) {
  // If e.which is undefined, considered as left mouse event.
  return e.which > 1;
} // 做向上兼容


exports.clientToLocal = clientToLocal;
exports.normalizeEvent = normalizeEvent;
exports.addEventListener = addEventListener;
exports.removeEventListener = removeEventListener;
exports.stop = stop;
exports.isMiddleOrRightButtonOnMouseUpDown = isMiddleOrRightButtonOnMouseUpDown;
exports.notLeftMouse = notLeftMouse;