/* Copyright (c) 2009 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 com.google.wave.api.event;

import com.google.wave.api.BlipData;
import com.google.wave.api.BlipThread;
import com.google.wave.api.Wavelet;
import com.google.wave.api.impl.EventMessageBundle;
import com.google.wave.api.impl.WaveletData;

import java.util.List;
import java.util.Map;

import javax.annotation.Nullable;

/**
 * Event triggered when a wavelet is fetched. This event is triggered after a
 * robot requests to see another wavelet. The robot has to be a participant of
 * the requested wavelet.
 */
public class WaveletFetchedEvent extends AbstractEvent {

  /** The message that was passed into the wavelet fetch operation. */
  private final String message;

  /** The fetched wavelet. */
  private final WaveletData waveletData;

  /** The blips that are associated with the fetched wavelet. */
  private final Map<String, BlipData> blips;

  /** The threads that are associated with the fetched wavelet. */
  private final Map<String, BlipThread> threads;

  /** Raw deltas.  Null if not requested. */
  @Nullable private final List<String> rawDeltas;

  /**
   * Raw snapshot.  The first element is the wavelet metadata, the
   * rest are blips.  Null if no snapshot was requested.
   */
  @Nullable private final List<String> rawSnapshot;

  /**
   * Constructor.
   *
   * @param wavelet the wavelet in which this event was triggered.
   * @param bundle the message bundle this event belongs to.
   * @param modifiedBy the id of the participant that triggered this event.
   * @param timestamp the timestamp of this event.
   * @param message the message that was passed into the wavelet fetch
   *     operation.
   * @param rootBlipId the root blip id of the wavelet where this event occurs.
   * @param waveletData the wavelet data of the fetched wavelet.
   * @param blips the blips of the fetched wavelet.
   * @param threads the threads of the fetched wavelet.
   */
  public WaveletFetchedEvent(Wavelet wavelet, EventMessageBundle bundle, String modifiedBy,
      Long timestamp, String message, String rootBlipId, WaveletData waveletData,
      Map<String, BlipData> blips, Map<String, BlipThread> threads,
      @Nullable List<String> rawDeltas, @Nullable List<String> rawSnapshot) {
    super(EventType.WAVELET_FETCHED, wavelet, bundle, modifiedBy, timestamp, rootBlipId);
    this.message = message;
    this.waveletData = waveletData;
    this.blips = blips;
    this.threads = threads;
    this.rawDeltas = rawDeltas;
    this.rawSnapshot = rawSnapshot;
  }

  /**
   * Constructor for deserialization.
   */
  WaveletFetchedEvent() {
    this.message = null;
    this.waveletData = null;
    this.blips = null;
    this.threads = null;
    this.rawDeltas = null;
    this.rawSnapshot = null;
  }

  /**
   * Returns the message that was passed into the wavelet fetch operation.
   *
   * @return the message that was passed into the wavelet fetch operation.
   */
  public String getMessage() {
    return message;
  }

  /**
   * Returns the fetched wavelet.
   *
   * @return an instance of {@link WaveletData} that represents the fetched
   *     wavelet.
   */
  public WaveletData getWaveletData() {
    return waveletData;
  }

  /**
   * Returns the blips that are associated with the fetched wavelet.
   *
   * @return a map of {@link BlipData} that are associated with the fetched
   *     wavelet.
   */
  public Map<String, BlipData> getBlips() {
    return blips;
  }

  /**
   * Returns the threads that are associated with the fetched wavelet.
   *
   * @return a map of {@link BlipThread} that are associated with the fetched
   *     wavelet.
   */
  public Map<String, BlipThread> getThreads() {
    return threads;
  }

  @Nullable public List<String> getRawDeltas() {
    return rawDeltas;
  }

  @Nullable public List<String> getRawSnapshot() {
    return rawSnapshot;
  }

  /**
   * Helper method for type conversion.
   *
   * @return the concrete type of this event, or {@code null} if it is of a
   *     different event type.
   */
  public static WaveletFetchedEvent as(Event event) {
    if (!(event instanceof WaveletFetchedEvent)) {
      return null;
    }
    return WaveletFetchedEvent.class.cast(event);
  }
}