/*
    * Licensed to the Apache Software Foundation (ASF) under one
    * or more contributor license agreements.  See the NOTICE file
    * distributed with this work for additional information
    * regarding copyright ownership.  The ASF licenses this file
    * to you 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.apache.maven.logging;
  
  import org.apache.maven.slf4j.MavenSimpleLogger;
  import org.slf4j.MDC;
  
  /**
   * Forwards log messages to the client.
   */
  public class ProjectBuildLogAppender implements AutoCloseable {
  
      private static final String KEY_PROJECT_ID = "maven.project.id";
      private static final ThreadLocal<String> PROJECT_ID = new InheritableThreadLocal<>();
      private static final ThreadLocal<String> FORKING_PROJECT_ID = new InheritableThreadLocal<>();
  
      public static String getProjectId() {
          return PROJECT_ID.get();
      }
  
      public static void setProjectId(String projectId) {
          String forkingProjectId = FORKING_PROJECT_ID.get();
          if (forkingProjectId != null) {
              if (projectId != null) {
                  projectId = forkingProjectId + "/" + projectId;
              } else {
                  projectId = forkingProjectId;
              }
          }
          if (projectId != null) {
              PROJECT_ID.set(projectId);
              MDC.put(KEY_PROJECT_ID, projectId);
          } else {
              PROJECT_ID.remove();
              MDC.remove(KEY_PROJECT_ID);
          }
      }
  
      public static void setForkingProjectId(String forkingProjectId) {
          if (forkingProjectId != null) {
              FORKING_PROJECT_ID.set(forkingProjectId);
          } else {
              FORKING_PROJECT_ID.remove();
          }
      }
  
      public static void updateMdc() {
          String id = getProjectId();
          if (id != null) {
              MDC.put(KEY_PROJECT_ID, id);
          } else {
              MDC.remove(KEY_PROJECT_ID);
          }
      }
  
      private final BuildEventListener buildEventListener;
  
      public ProjectBuildLogAppender(BuildEventListener buildEventListener) {
          this.buildEventListener = buildEventListener;
          MavenSimpleLogger.setLogSink(this::accept);
      }
  
      protected void accept(String message) {
          String projectId = MDC.get(KEY_PROJECT_ID);
          buildEventListener.projectLogMessage(projectId, message);
      }
  
      @Override
      public void close() throws Exception {
          MavenSimpleLogger.setLogSink(null);
      }
  }