text: // Copyright 2008 The Closure Library Authors. All Rights Reserved.
  //
  // 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.
  
  /**
   * @fileoverview Renderer for {@link goog.ui.ColorMenuButton}s.
   */
  
  goog.provide('goog.ui.ColorMenuButtonRenderer');
  
  goog.require('goog.asserts');
  goog.require('goog.color');
  goog.require('goog.dom.TagName');
  goog.require('goog.dom.classlist');
  goog.require('goog.ui.MenuButtonRenderer');
  
  
  
  /**
   * Renderer for {@link goog.ui.ColorMenuButton}s.
   * @constructor
   * @extends {goog.ui.MenuButtonRenderer}
   */
  goog.ui.ColorMenuButtonRenderer = function() {
    goog.ui.MenuButtonRenderer.call(this);
  };
  goog.inherits(goog.ui.ColorMenuButtonRenderer, goog.ui.MenuButtonRenderer);
  goog.addSingletonGetter(goog.ui.ColorMenuButtonRenderer);
  
  
  /**
   * Default CSS class to be applied to the root element of components rendered
   * by this renderer.
   * @type {string}
   */
  goog.ui.ColorMenuButtonRenderer.CSS_CLASS =
      goog.getCssName('goog-color-menu-button');
  
  
  /**
   * Overrides the superclass implementation by wrapping the caption text or DOM
   * structure in a color indicator element.  Creates the following DOM structure:
   *
   *    <div class="goog-inline-block goog-menu-button-caption">
   *      <div class="goog-color-menu-button-indicator">
   *        Contents...
   *      </div>
   *    </div>
   *
   * The 'goog-color-menu-button-indicator' style should be defined to have a
   * bottom border of nonzero width and a default color that blends into its
   * background.
   * @param {goog.ui.ControlContent} content Text caption or DOM structure.
   * @param {goog.dom.DomHelper} dom DOM helper, used for document interaction.
   * @return {Element} Caption element.
   * @override
   */
  goog.ui.ColorMenuButtonRenderer.prototype.createCaption = function(
      content, dom) {
    return goog.ui.ColorMenuButtonRenderer.superClass_.createCaption.call(
        this, goog.ui.ColorMenuButtonRenderer.wrapCaption(content, dom), dom);
  };
  
  
  /**
   * Wrap a caption in a div with the color-menu-button-indicator CSS class.
   * @param {goog.ui.ControlContent} content Text caption or DOM structure.
   * @param {goog.dom.DomHelper} dom DOM helper, used for document interaction.
   * @return {!Element} Caption element.
   */
  goog.ui.ColorMenuButtonRenderer.wrapCaption = function(content, dom) {
    return dom.createDom(
        goog.dom.TagName.DIV,
        goog.getCssName(goog.ui.ColorMenuButtonRenderer.CSS_CLASS, 'indicator'),
        content);
  };
  
  
  /**
   * Takes a color menu button control's root element and a value object
   * (which is assumed to be a color), and updates the button's DOM to reflect
   * the new color.  Overrides {@link goog.ui.ButtonRenderer#setValue}.
   * @param {Element} element The button control's root element (if rendered).
   * @param {*} value New value; assumed to be a color spec string.
   * @override
   */
  goog.ui.ColorMenuButtonRenderer.prototype.setValue = function(element, value) {
    if (element) {
      goog.ui.ColorMenuButtonRenderer.setCaptionValue(
          this.getContentElement(element), value);
    }
  };
  
  
  /**
   * Takes a control's content element and a value object (which is assumed
   * to be a color), and updates its DOM to reflect the new color.
   * @param {Element} caption A content element of a control.
   * @param {*} value New value; assumed to be a color spec string.
   */
  goog.ui.ColorMenuButtonRenderer.setCaptionValue = function(caption, value) {
    // Assume that the caption's first child is the indicator.
    if (caption && caption.firstChild) {
      // Normalize the value to a hex color spec or null (otherwise setting
      // borderBottomColor will cause a JS error on IE).
      var hexColor;
  
      var strValue = /** @type {string} */ (value);
      hexColor = strValue && goog.color.isValidColor(strValue) ?
          goog.color.parse(strValue).hex :
          null;
  
      caption.firstChild.style.borderBottomColor = hexColor || 'transparent';
    }
  };
  
  
  /**
   * Initializes the button's DOM when it enters the document.  Overrides the
   * superclass implementation by making sure the button's color indicator is
   * initialized.
   * @param {goog.ui.Control} button goog.ui.ColorMenuButton whose DOM is to be
   *     initialized as it enters the document.
   * @override
   */
  goog.ui.ColorMenuButtonRenderer.prototype.initializeDom = function(button) {
    var buttonElement = button.getElement();
    goog.asserts.assert(buttonElement);
    this.setValue(buttonElement, button.getValue());
    goog.dom.classlist.add(
        buttonElement, goog.ui.ColorMenuButtonRenderer.CSS_CLASS);
    goog.ui.ColorMenuButtonRenderer.superClass_.initializeDom.call(this, button);
  };
  