src/third_party/devtools/front_end/object_ui/CustomPreviewComponent.js

// Copyright 2014 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
/**
 * @unrestricted
 */
class CustomPreviewSection {
  /**
   * @param {!SDK.RemoteObject} object
   */
  constructor(object) {
    this._sectionElement = createElementWithClass('span', 'custom-expandable-section');
    this._object = object;
    this._expanded = false;
    this._cachedContent = null;
    const customPreview = object.customPreview();

    let headerJSON;
    try {
      headerJSON = JSON.parse(customPreview.header);
    } catch (e) {
      Common.console.error('Broken formatter: header is invalid json ' + e);
      return;
    }
    this._header = this._renderJSONMLTag(headerJSON);
    if (this._header.nodeType === Node.TEXT_NODE) {
      Common.console.error('Broken formatter: header should be an element node.');
      return;
    }

    if (customPreview.hasBody || customPreview.bodyGetterId) {
      this._header.classList.add('custom-expandable-section-header');
      this._header.addEventListener('click', this._onClick.bind(this), false);
      this._expandIcon = UI.Icon.create('smallicon-triangle-right', 'custom-expand-icon');
      this._header.insertBefore(this._expandIcon, this._header.firstChild);
    }

    this._sectionElement.appendChild(this._header);
  }

  /**
   * @return {!Element}
   */
  element() {
    return this._sectionElement;
  }

  /**
   * @param {*} jsonML
   * @return {!Node}
   */
  _renderJSONMLTag(jsonML) {
    if (!Array.isArray(jsonML)) {
      return createTextNode(jsonML + '');
    }

    const array = /** @type {!Array.<*>} */ (jsonML);
    return array[0] === 'object' ? this._layoutObjectTag(array) : this._renderElement(array);
  }

  /**
   *
   * @param {!Array.<*>} object
   * @return {!Node}
   */
  _renderElement(object) {
    const tagName = object.shift();
    if (!CustomPreviewSection._tagsWhiteList.has(tagName)) {
      Common.console.error('Broken formatter: element ' + tagName + ' is not allowed!');
      return createElement('span');
    }
    const element = createElement(/** @type {string} */ (tagName));
    if ((typeof object[0] === 'object') && !Array.isArray(object[0])) {
      const attributes = object.shift();
      for (const key in attributes) {
        const value = attributes[key];
        if ((key !== 'style') || (typeof value !== 'string')) {
          continue;
        }

        element.setAttribute(key, value);
      }
    }

    this._appendJsonMLTags(element, object);
    return element;
  }

  /**
   * @param {!Array.<*>} objectTag
   * @return {!Node}
   */
  _layoutObjectTag(objectTag) {
    objectTag.shift();
    const attributes = objectTag.shift();
    const remoteObject = this._object.runtimeModel().createRemoteObject(
        /** @type {!Protocol.Runtime.RemoteObject} */ (attributes));
    if (remoteObject.customPreview()) {
      return (new CustomPreviewSection(remoteObject)).element();
    }

    const sectionElement = ObjectUI.ObjectPropertiesSection.defaultObjectPresentation(remoteObject);
    sectionElement.classList.toggle('custom-expandable-section-standard-section', remoteObject.hasChildren);
    return sectionElement;
  }

  /**
   * @param {!Node} parentElement
   * @param {!Array.<*>} jsonMLTags
   */
  _appendJsonMLTags(parentElement, jsonMLTags) {
    for (let i = 0; i < jsonMLTags.length; ++i) {
      parentElement.appendChild(this._renderJSONMLTag(jsonMLTags[i]));
    }
  }

  /**
   * @param {!Event} event
   */
  _onClick(event) {
    event.consume(true);
    if (this._cachedContent) {
      this._toggleExpand();
    } else {
      this._loadBody();
    }
  }

  _toggleExpand() {
    this._expanded = !this._expanded;
    this._header.classList.toggle('expanded', this._expanded);
    this._cachedContent.classList.toggle('hidden', !this._expanded);
    if (this._expanded) {
      this._expandIcon.setIconType('smallicon-triangle-down');
    } else {
      this._expandIcon.setIconType('smallicon-triangle-right');
    }
  }

  _loadBody() {
    /**
     * @suppressReceiverCheck
     * @suppressGlobalPropertiesCheck
     * @suppress {undefinedVars}
     * @this {Object}
     * @param {function(!Object, *):*} bindRemoteObject
     * @param {*=} formatter
     * @param {*=} config
     */
    function load(bindRemoteObject, formatter, config) {
      /**
       * @param {*} jsonMLObject
       * @throws {string} error message
       */
      function substituteObjectTagsInCustomPreview(jsonMLObject) {
        if (!jsonMLObject || (typeof jsonMLObject !== 'object') || (typeof jsonMLObject.splice !== 'function')) {
          return;
        }

        const obj = jsonMLObject.length;
        if (!(typeof obj === 'number' && obj >>> 0 === obj && (obj > 0 || 1 / obj > 0))) {
          return;
        }

        let startIndex = 1;
        if (jsonMLObject[0] === 'object') {
          const attributes = jsonMLObject[1];
          const originObject = attributes['object'];
          const config = attributes['config'];
          if (typeof originObject === 'undefined') {
            throw 'Illegal format: obligatory attribute "object" isn\'t specified';
          }

          jsonMLObject[1] = bindRemoteObject(originObject, config);
          startIndex = 2;
        }
        for (let i = startIndex; i < jsonMLObject.length; ++i) {
          substituteObjectTagsInCustomPreview(jsonMLObject[i]);
        }
      }

      try {
        const body = formatter.body(this, config);
        substituteObjectTagsInCustomPreview(body);
        return body;
      } catch (e) {
        console.error('Custom Formatter Failed: ' + e);
        return null;
      }
    }

    const customPreview = this._object.customPreview();
    if (customPreview.bindRemoteObjectFunctionId && customPreview.formatterObjectId) {
      // Support for V8 version < 7.3.
      const args = [{objectId: customPreview.bindRemoteObjectFunctionId}, {objectId: customPreview.formatterObjectId}];
      if (customPreview.configObjectId) {
        args.push({objectId: customPreview.configObjectId});
      }
      this._object.callFunctionJSON(load, args).then(onBodyLoaded.bind(this));
    } else if (customPreview.bodyGetterId) {
      this._object.callFunctionJSON(bodyGetter => bodyGetter(), [{objectId: customPreview.bodyGetterId}])
          .then(onBodyLoaded.bind(this));
    }

    /**
     * @param {*} bodyJsonML
     * @this {CustomPreviewSection}
     */
    function onBodyLoaded(bodyJsonML) {
      if (!bodyJsonML) {
        return;
      }

      this._cachedContent = this._renderJSONMLTag(bodyJsonML);
      this._sectionElement.appendChild(this._cachedContent);
      this._toggleExpand();
    }
  }
}

/**
 * @unrestricted
 */
export default class CustomPreviewComponent {
  /**
   * @param {!SDK.RemoteObject} object
   */
  constructor(object) {
    this._object = object;
    this._customPreviewSection = new CustomPreviewSection(object);
    this.element = createElementWithClass('span', 'source-code');
    const shadowRoot = UI.createShadowRootWithCoreStyles(this.element, 'object_ui/customPreviewComponent.css');
    this.element.addEventListener('contextmenu', this._contextMenuEventFired.bind(this), false);
    shadowRoot.appendChild(this._customPreviewSection.element());
  }

  expandIfPossible() {
    if ((this._object.customPreview().hasBody || this._object.customPreview().bodyGetterId) &&
        this._customPreviewSection) {
      this._customPreviewSection._loadBody();
    }
  }

  /**
   * @param {!Event} event
   */
  _contextMenuEventFired(event) {
    const contextMenu = new UI.ContextMenu(event);
    if (this._customPreviewSection) {
      contextMenu.revealSection().appendItem(
          Common.UIString('Show as JavaScript object'), this._disassemble.bind(this));
    }
    contextMenu.appendApplicableItems(this._object);
    contextMenu.show();
  }

  _disassemble() {
    this.element.shadowRoot.textContent = '';
    this._customPreviewSection = null;
    this.element.shadowRoot.appendChild(ObjectUI.ObjectPropertiesSection.defaultObjectPresentation(this._object));
  }
}

CustomPreviewSection._tagsWhiteList = new Set(['span', 'div', 'ol', 'li', 'table', 'tr', 'td']);

/* Legacy exported object */
self.ObjectUI = self.ObjectUI || {};

/* Legacy exported object */
ObjectUI = ObjectUI || {};

/** @constructor */
ObjectUI.CustomPreviewComponent = CustomPreviewComponent;