// FIXME works for View2D only

goog.provide('ol.interaction.KeyboardZoom');

goog.require('goog.asserts');
goog.require('goog.events.KeyHandler.EventType');
goog.require('ol.interaction.ConditionType');
goog.require('ol.interaction.Interaction');


/**
 * @define {number} Zoom duration.
 */
ol.interaction.KEYBOARD_ZOOM_DURATION = 100;



/**
 * @constructor
 * @param {ol.interaction.ConditionType} condition Condition.
 * @param {ol.interaction.KeyboardZoomOptions=} opt_options Options.
 * @extends {ol.interaction.Interaction}
 */
ol.interaction.KeyboardZoom = function(condition, opt_options) {

  goog.base(this);

  var options = goog.isDef(opt_options) ? opt_options : {};

  /**
   * @private
   * @type {ol.interaction.ConditionType}
   */
  this.condition_ = condition;

  /**
   * @private
   * @type {number}
   */
  this.delta_ = goog.isDef(options.delta) ? options.delta : 1;

};
goog.inherits(ol.interaction.KeyboardZoom, ol.interaction.Interaction);


/**
 * @inheritDoc
 */
ol.interaction.KeyboardZoom.prototype.handleMapBrowserEvent =
    function(mapBrowserEvent) {
  if (mapBrowserEvent.type == goog.events.KeyHandler.EventType.KEY) {
    var keyEvent = /** @type {goog.events.KeyEvent} */
        (mapBrowserEvent.browserEvent);
    var charCode = keyEvent.charCode;
    if (this.condition_(keyEvent) &&
        (charCode == '+'.charCodeAt(0) || charCode == '-'.charCodeAt(0))) {
      var map = mapBrowserEvent.map;
      var delta = (charCode == '+'.charCodeAt(0)) ? this.delta_ : -this.delta_;
      map.requestRenderFrame();
      // FIXME works for View2D only
      var view = map.getView().getView2D();
      ol.interaction.Interaction.zoomByDelta(map, view, delta, undefined,
          ol.interaction.KEYBOARD_ZOOM_DURATION);
      keyEvent.preventDefault();
      mapBrowserEvent.preventDefault();
    }
  }
};