// Based on https://github.com/Polymer/PointerEvents

// Copyright (c) 2013 The Polymer Authors. All rights reserved.
//
// Redistribution and use in source and binary forms, with or without
// modification, are permitted provided that the following conditions are
// met:
//
// * Redistributions of source code must retain the above copyright
// notice, this list of conditions and the following disclaimer.
// * Redistributions in binary form must reproduce the above
// copyright notice, this list of conditions and the following disclaimer
// in the documentation and/or other materials provided with the
// distribution.
// * Neither the name of Google Inc. nor the names of its
// contributors may be used to endorse or promote products derived from
// this software without specific prior written permission.
//
// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

goog.provide('ol.pointer.PointerEvent');


goog.require('goog.events');
goog.require('goog.events.Event');



/**
 * A class for pointer events.
 *
 * This class is used as an abstraction for mouse events,
 * touch events and even native pointer events.
 *
 * @constructor
 * @extends {goog.events.Event}
 * @param {string} type The type of the event to create.
 * @param {goog.events.BrowserEvent} browserEvent
 * @param {Object.<string, ?>=} opt_eventDict An optional dictionary of
 *    initial event properties.
 */
ol.pointer.PointerEvent = function(type, browserEvent, opt_eventDict) {
  goog.base(this, type);

  /**
   * @const
   * @type {goog.events.BrowserEvent}
   */
  this.browserEvent = browserEvent;

  /**
   * @const
   * @type {Event}
   */
  this.originalEvent = browserEvent.getBrowserEvent();

  var eventDict = goog.isDef(opt_eventDict) ? opt_eventDict : {};

  /**
   * @type {number}
   */
  this.buttons = this.getButtons_(eventDict);

  /**
   * @type {number}
   */
  this.pressure = this.getPressure_(eventDict, this.buttons);

  // MouseEvent related properties

  /**
   * @type {boolean}
   */
  this.bubbles = this.getValue_('bubbles', eventDict);

  /**
   * @type {boolean}
   */
  this.cancelable = this.getValue_('cancelable', eventDict);

  /**
   * @type {Object}
   */
  this.view = this.getValue_('view', eventDict);

  /**
   * @type {number}
   */
  this.detail = this.getValue_('detail', eventDict);

  /**
   * @type {number}
   */
  this.screenX = this.getValue_('screenX', eventDict);

  /**
   * @type {number}
   */
  this.screenY = this.getValue_('screenY', eventDict);

  /**
   * @type {number}
   */
  this.clientX = this.getValue_('clientX', eventDict);

  /**
   * @type {number}
   */
  this.clientY = this.getValue_('clientY', eventDict);

  /**
   * @type {boolean}
   */
  this.ctrlKey = this.getValue_('ctrlKey', eventDict);

  /**
   * @type {boolean}
   */
  this.altKey = this.getValue_('altKey', eventDict);

  /**
   * @type {boolean}
   */
  this.shiftKey = this.getValue_('shiftKey', eventDict);

  /**
   * @type {boolean}
   */
  this.metaKey = this.getValue_('metaKey', eventDict);

  /**
   * @type {number}
   */
  this.button = this.getValue_('button', eventDict);

  /**
   * @type {Node}
   */
  this.relatedTarget = this.getValue_('relatedTarget', eventDict);

  // PointerEvent related properties

  /**
   * @const
   * @type {number}
   */
  this.pointerId = this.getValueOr_('pointerId', 0, eventDict);

  /**
   * @type {number}
   */
  this.width = this.getValueOr_('width', 0, eventDict);

  /**
   * @type {number}
   */
  this.height = this.getValueOr_('height', 0, eventDict);

  /**
   * @type {number}
   */
  this.tiltX = this.getValueOr_('tiltX', 0, eventDict);

  /**
   * @type {number}
   */
  this.tiltY = this.getValueOr_('tiltY', 0, eventDict);

  /**
   * @type {string}
   */
  this.pointerType = this.getValueOr_('pointerType', '', eventDict);

  /**
   * @type {number}
   */
  this.hwTimestamp = this.getValueOr_('hwTimestamp', 0, eventDict);

  /**
   * @type {boolean}
   */
  this.isPrimary = this.getValueOr_('isPrimary', false, eventDict);

};
goog.inherits(ol.pointer.PointerEvent, goog.events.Event);


/**
 * @private
 * @param {string} key
 * @param {Object.<string, ?>} eventDict
 * @return {string|number|?}
 */
ol.pointer.PointerEvent.prototype.getValue_ = function(key, eventDict) {
  return goog.isDefAndNotNull(eventDict[key]) ?
      eventDict[key] :
      ol.pointer.PointerEvent.MOUSE_DEFAULTS['relatedTarget'];
};


/**
 * @private
 * @param {string} key
 * @param {*} defaultValue
 * @param {Object.<string, ?>} eventDict
 * @return {string|number|?}
 */
ol.pointer.PointerEvent.prototype.getValueOr_ =
    function(key, defaultValue, eventDict) {
  return goog.isDefAndNotNull(eventDict[key]) ?
      eventDict[key] : defaultValue;
};


/**
 * @private
 * @param {Object.<string, ?>} eventDict
 * @return {number}
 */
ol.pointer.PointerEvent.prototype.getButtons_ = function(eventDict) {
  // According to the w3c spec,
  // http://www.w3.org/TR/DOM-Level-3-Events/#events-MouseEvent-button
  // MouseEvent.button == 0 can mean either no mouse button depressed, or the
  // left mouse button depressed.
  //
  // As of now, the only way to distinguish between the two states of
  // MouseEvent.button is by using the deprecated MouseEvent.which property, as
  // this maps mouse buttons to positive integers > 0, and uses 0 to mean that
  // no mouse button is held.
  //
  // MouseEvent.which is derived from MouseEvent.button at MouseEvent creation,
  // but initMouseEvent does not expose an argument with which to set
  // MouseEvent.which. Calling initMouseEvent with a buttonArg of 0 will set
  // MouseEvent.button == 0 and MouseEvent.which == 1, breaking the expectations
  // of app developers.
  //
  // The only way to propagate the correct state of MouseEvent.which and
  // MouseEvent.button to a new MouseEvent.button == 0 and MouseEvent.which == 0
  // is to call initMouseEvent with a buttonArg value of -1.
  //
  // This is fixed with DOM Level 4's use of buttons
  var buttons;
  if (eventDict.buttons || ol.pointer.PointerEvent.HAS_BUTTONS) {
    buttons = eventDict.buttons;
  } else {
    switch (eventDict.which) {
      case 1: buttons = 1; break;
      case 2: buttons = 4; break;
      case 3: buttons = 2; break;
      default: buttons = 0;
    }
  }
  return buttons;
};


/**
 * @private
 * @param {Object.<string, ?>} eventDict
 * @param {number} buttons
 * @return {number}
 */
ol.pointer.PointerEvent.prototype.getPressure_ = function(eventDict, buttons) {
  // Spec requires that pointers without pressure specified use 0.5 for down
  // state and 0 for up state.
  var pressure = 0;
  if (eventDict.pressure) {
    pressure = eventDict.pressure;
  } else {
    pressure = buttons ? 0.5 : 0;
  }
  return pressure;
};


/**
 * Does the browser support the `MouseEvent` type?
 * @type {boolean}
 */
ol.pointer.PointerEvent.NEW_MOUSE_EVENT = false;


/**
 * Is the `buttons` property supported?
 * @type {boolean}
 */
ol.pointer.PointerEvent.HAS_BUTTONS = false;


/**
 * Checks if the `MouseEvent` type is supported.
 */
ol.pointer.PointerEvent.checkNewMouseEvent = function() {
  try {
    var ev = ol.pointer.PointerEvent.createMouseEvent('click', {buttons: 1});
    ol.pointer.PointerEvent.NEW_MOUSE_EVENT = true;
    ol.pointer.PointerEvent.HAS_BUTTONS = ev.buttons === 1;
  } catch (e) {
  }
};
ol.pointer.PointerEvent.checkNewMouseEvent();


/**
 * Warning is suppressed because Closure thinks the MouseEvent
 * constructor takes no arguments.
 * @param {string} inType The type of the event to create.
 * @param {Object} inDict An dictionary of initial event properties.
 * @return {MouseEvent}
 * @suppress {checkTypes}
 */
ol.pointer.PointerEvent.createMouseEvent = function(inType, inDict) {
  return new MouseEvent(inType, inDict);
};


/**
 * List of default values when creating an event.
 */
ol.pointer.PointerEvent.MOUSE_DEFAULTS = {
  'bubbles': false,
  'cancelable': false,
  'view': null,
  'detail': null,
  'screenX': 0,
  'screenY': 0,
  'clientX': 0,
  'clientY': 0,
  'ctrlKey': false,
  'altKey': false,
  'shiftKey': false,
  'metaKey': false,
  'button': 0,
  'relatedTarget': null
};