<!--
Copyright (C) 2016 The Android Open Source Project

Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.
You may obtain a copy of the License at

http://www.apache.org/licenses/LICENSE-2.0

Unless required by applicable law or agreed to in writing, software
distributed under the License is distributed on an "AS IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
See the License for the specific language governing permissions and
limitations under the License.
-->
<link rel="import" href="../bower_components/polymer/polymer.html">
<script>
(function(window) {
  'use strict';

  /** @polymerBehavior Gerrit.KeyboardShortcutBehavior */
  var KeyboardShortcutBehavior = {
    // Set of identifiers currently blocking keyboard shortcuts. Stored as
    // a map of string to the value of true.
    _disablers: {},

    properties: {
      keyEventTarget: {
        type: Object,
        value: function() { return this; },
      },

      _boundKeyHandler: {
        type: Function,
        readonly: true,
        value: function() { return this._handleKey.bind(this); },
      },
    },

    attached: function() {
      this.keyEventTarget.addEventListener('keydown', this._boundKeyHandler);
    },

    detached: function() {
      this.keyEventTarget.removeEventListener('keydown', this._boundKeyHandler);
    },

    shouldSuppressKeyboardShortcut: function(e) {
      for (var c in KeyboardShortcutBehavior._disablers) {
        if (KeyboardShortcutBehavior._disablers[c] === true) {
          return true;
        }
      }
      var getModifierState = e.getModifierState ?
          e.getModifierState.bind(e) :
          function() { return false; };
      var target = e.detail ? e.detail.keyboardEvent : e.target;
      return getModifierState('Control') ||
             getModifierState('Alt') ||
             getModifierState('Meta') ||
             getModifierState('Fn') ||
             target.tagName == 'INPUT' ||
             target.tagName == 'TEXTAREA' ||
             target.tagName == 'SELECT' ||
             target.tagName == 'BUTTON' ||
             target.tagName == 'A' ||
             target.tagName == 'GR-BUTTON';
    },

    disable: function(id) {
      KeyboardShortcutBehavior._disablers[id] = true;
    },

    enable: function(id) {
      delete KeyboardShortcutBehavior._disablers[id];
    },
  };

  window.Gerrit = window.Gerrit || {};
  window.Gerrit.KeyboardShortcutBehavior = KeyboardShortcutBehavior;
})(window);
</script>