/**
 * Copyright 2010 Google Inc.
 *
 * 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.
 */
package org.waveprotocol.wave.client.wavepanel.view.dom;

import static org.waveprotocol.wave.client.wavepanel.view.dom.DomViewHelper.load;

import com.google.gwt.dom.client.Element;

import org.waveprotocol.wave.client.wavepanel.view.IntrinsicBlipView;
import org.waveprotocol.wave.client.wavepanel.view.dom.full.BlipViewBuilder.Components;

/**
 * BlipViewDomImpl of the blip view.
 *
 */
public final class BlipViewDomImpl implements DomView, IntrinsicBlipView {

  /** The DOM element of this view. */
  private final Element self;

  /** The HTML id of {@code self}. */
  private final String id;

  //
  // UI fields for both intrinsic and structural elements.
  // Element references are loaded lazily and cached.
  //

  private Element meta;
  private Element replies;
  private Element conversations;

  BlipViewDomImpl(Element self, String id) {
    this.self = self;
    this.id = id;
  }

  public static BlipViewDomImpl of(Element e) {
    return new BlipViewDomImpl(e, e.getId());
  }

  //
  // Generated code. There is no informative content in the code below.
  //

  public Element getMetaHolder() {
    if (meta == null) {
      meta = self.getFirstChildElement();
    }
    return meta;
  }

  //
  // Structural elements are public, in order to export structural control.
  //

  public Element getDefaultAnchors() {
    if (replies == null) {
      replies = load(id, Components.REPLIES);
    }
    return replies;
  }

  public Element getConversations() {
    if (conversations == null) {
      conversations = load(id, Components.PRIVATE_REPLIES);
    }
    return conversations;
  }

  public void remove() {
    getElement().removeFromParent();
  }

  //
  // DomView nature.
  //

  @Override
  public Element getElement() {
    return self;
  }

  @Override
  public String getId() {
    return id;
  }

  @Override
  public boolean equals(Object obj) {
    return DomViewHelper.equals(this, obj);
  }

  @Override
  public int hashCode() {
    return DomViewHelper.hashCode(this);
  }
}