/*
 * Copyright 2017 Cisco Systems, 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.cisco.gerrit.plugins.slack.message;

import com.cisco.gerrit.plugins.slack.config.ProjectConfig;
import com.google.gerrit.server.events.ChangeMergedEvent;
import com.google.gerrit.server.events.CommentAddedEvent;
import com.google.gerrit.server.events.Event;
import com.google.gerrit.server.events.PatchSetCreatedEvent;
import com.google.gerrit.server.events.PrivateStateChangedEvent;
import com.google.gerrit.server.events.ReviewerAddedEvent;
import com.google.gerrit.server.events.WorkInProgressStateChangedEvent;

/**
 * Factory used to create event specific MessageGenerator instances.
 *
 * @author Matthew Montgomery
 */
public class MessageGeneratorFactory {
  // Made private to prevent instantiation
  private MessageGeneratorFactory() {}

  /**
   * Creates a new MessageGenerator for patchset created events.
   *
   * @param event A PatchSetCreatedEvent instance
   * @param config A ProjectConfig instance for the given event
   * @return A MessageGenerator instance capable of generating a message for a PatchSetCreatedEvent.
   */
  public static MessageGenerator newInstance(PatchSetCreatedEvent event, ProjectConfig config) {
    PatchSetCreatedMessageGenerator messageGenerator;
    messageGenerator = new PatchSetCreatedMessageGenerator(event, config);

    return messageGenerator;
  }

  /**
   * Creates a new MessageGenerator for change merged events.
   *
   * @param event A ChangeMergedEvent instance
   * @param config A ProjectConfig instance for the given event
   * @return A MessageGenerator instance capable of generating a message for a ChangeMergedEvent.
   */
  public static MessageGenerator newInstance(ChangeMergedEvent event, ProjectConfig config) {
    ChangeMergedMessageGenerator messageGenerator;
    messageGenerator = new ChangeMergedMessageGenerator(event, config);

    return messageGenerator;
  }

  /**
   * Creates a new MessageGenerator for comment added events.
   *
   * @param event A CommentAddedEvent instance
   * @param config A ProjectConfig instance for the given event
   * @return A MessageGenerator instance capable of generating a message for a CommentAddedEvent.
   */
  public static MessageGenerator newInstance(CommentAddedEvent event, ProjectConfig config) {
    CommentAddedMessageGenerator messageGenerator;
    messageGenerator = new CommentAddedMessageGenerator(event, config);

    return messageGenerator;
  }

  /**
   * Creates a new MessageGenerator for reviewer added events.
   *
   * @param event A ReviewerAddedEvent instance
   * @param config A ProjectConfig instance for the given event
   * @return A MessageGenerator instance capable of generating a message for a ReviewerAddedEvent.
   */
  public static MessageGenerator newInstance(ReviewerAddedEvent event, ProjectConfig config) {
    ReviewerAddedMessageGenerator messageGenerator;
    messageGenerator = new ReviewerAddedMessageGenerator(event, config);

    return messageGenerator;
  }

  /**
   * Creates a new MessageGenerator for work-in-progress state changed events.
   *
   * @param event A WorkInProgressStateChangedEvent instance
   * @param config A ProjectConfig instance for the given event
   * @return A MessageGenerator instance capable of generating a message for a
   *     WorkInProgressStateChangedEvent.
   */
  public static MessageGenerator newInstance(
      WorkInProgressStateChangedEvent event, ProjectConfig config) {
    WorkInProgressStateChangedGenerator messageGenerator;
    messageGenerator = new WorkInProgressStateChangedGenerator(event, config);

    return messageGenerator;
  }

  /**
   * Creates a new MessageGenerator for private state changed events.
   *
   * @param event A PrivateStateChangedEvent instance
   * @param config A ProjectConfig instance for the given event
   * @return A MessageGenerator instance capable of generating a message for a
   *     PrivateStateChangedEvent.
   */
  public static MessageGenerator newInstance(PrivateStateChangedEvent event, ProjectConfig config) {
    PrivateStateChangedGenerator messageGenerator;
    messageGenerator = new PrivateStateChangedGenerator(event, config);

    return messageGenerator;
  }

  /**
   * Creates a new MessageGenerator for unsupported events.
   *
   * @param event An Event instance
   * @return A MessageGenerator instance capable of generating a message for an unsupported Event.
   */
  public static MessageGenerator newInstance(Event event) {
    UnsupportedMessageGenerator messageGenerator;
    messageGenerator = new UnsupportedMessageGenerator(event);

    return messageGenerator;
  }
}