polygerrit-ui/app/elements/diff/gr-selection-action-box/gr-selection-action-box.js

/**
 * @license
 * 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.
 */
(function() {
  'use strict';

  /**
    * @appliesMixin Gerrit.FireMixin
    */
  class GrSelectionActionBox extends Polymer.mixinBehaviors( [
    Gerrit.FireBehavior,
  ], Polymer.GestureEventListeners(
      Polymer.LegacyElementMixin(
          Polymer.Element))) {
    static get is() { return 'gr-selection-action-box'; }
    /**
     * Fired when the comment creation action was taken (click).
     *
     * @event create-comment-requested
     */

    static get properties() {
      return {
        keyEventTarget: {
          type: Object,
          value() { return document.body; },
        },
        positionBelow: Boolean,
      };
    }

    created() {
      super.created();

      // See https://crbug.com/gerrit/4767
      this.addEventListener('mousedown',
          e => this._handleMouseDown(e));
    }

    placeAbove(el) {
      Polymer.dom.flush();
      const rect = this._getTargetBoundingRect(el);
      const boxRect = this.$.tooltip.getBoundingClientRect();
      const parentRect = this._getParentBoundingClientRect();
      this.style.top =
          rect.top - parentRect.top - boxRect.height - 6 + 'px';
      this.style.left =
          rect.left - parentRect.left + (rect.width - boxRect.width) / 2 + 'px';
    }

    placeBelow(el) {
      Polymer.dom.flush();
      const rect = this._getTargetBoundingRect(el);
      const boxRect = this.$.tooltip.getBoundingClientRect();
      const parentRect = this._getParentBoundingClientRect();
      this.style.top =
      rect.top - parentRect.top + boxRect.height - 6 + 'px';
      this.style.left =
      rect.left - parentRect.left + (rect.width - boxRect.width) / 2 + 'px';
    }

    _getParentBoundingClientRect() {
      // With native shadow DOM, the parent is the shadow root, not the gr-diff
      // element
      const parent = this.parentElement || this.parentNode.host;
      return parent.getBoundingClientRect();
    }

    _getTargetBoundingRect(el) {
      let rect;
      if (el instanceof Text) {
        const range = document.createRange();
        range.selectNode(el);
        rect = range.getBoundingClientRect();
        range.detach();
      } else {
        rect = el.getBoundingClientRect();
      }
      return rect;
    }

    _handleMouseDown(e) {
      if (e.button !== 0) { return; } // 0 = main button
      e.preventDefault();
      e.stopPropagation();
      this.fire('create-comment-requested');
    }
  }

  customElements.define(GrSelectionActionBox.is, GrSelectionActionBox);
})();