/**
 * 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.box.server.rpc.render.view.builder;

import static org.waveprotocol.box.server.rpc.render.uibuilder.BuilderHelper.nonNull;

import com.google.common.annotations.VisibleForTesting;
import com.google.common.base.Preconditions;

import org.waveprotocol.box.server.rpc.render.common.safehtml.SafeHtmlBuilder;
import org.waveprotocol.box.server.rpc.render.uibuilder.OutputHelper;
import org.waveprotocol.box.server.rpc.render.uibuilder.UiBuilder;
import org.waveprotocol.box.server.rpc.render.view.TypeCodes;
import org.waveprotocol.box.server.rpc.render.view.View.Type;

/**
 * UI builder for an inline thread.
 *
 */
public final class AnchorViewBuilder implements UiBuilder {

  /**
   * A unique id for this builder.
   */
  private final String id;

  //
  // Structural components.
  //

  private final UiBuilder thread;

  /**
   * Creates an anchor view.
   *
   * @param id HTML-escaped value of the anchor's DOM id
   * @param thread UI of the thread positioned at this anchor
   */
  public static AnchorViewBuilder create(String id, UiBuilder thread) {
    // Cheap semi-reliable check of escapedness.
    Preconditions.checkArgument(id == null || !id.contains("\'"));
    return new AnchorViewBuilder(id, nonNull(thread));
  }

  @VisibleForTesting
  AnchorViewBuilder(String id, UiBuilder thread) {
    this.id = id;
    this.thread = thread;
  }

  @Override
  public void outputHtml(SafeHtmlBuilder output) {
    OutputHelper.openSpan(output, id, null, TypeCodes.kind(Type.ANCHOR));
    thread.outputHtml(output);
    OutputHelper.closeSpan(output);
  }

}