/*
    * 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.plugins.shade.resource;
  
  import java.io.IOException;
  import java.io.InputStream;
  import java.nio.charset.StandardCharsets;
  import java.util.ArrayList;
  import java.util.List;
  import java.util.Scanner;
  import java.util.jar.JarEntry;
  import java.util.jar.JarOutputStream;
  
  import org.apache.commons.io.IOUtils;
  import org.apache.maven.plugins.shade.relocation.Relocator;
  
  /**
   * Resource transformer that relocates classes in {@code META-INF/sisu/javax.inject.Named} and appends resources
   * into a single resource.
   *
   * @since 3.3.0
   */
  public class SisuIndexResourceTransformer extends AbstractCompatibilityTransformer {
      private static final String SISU_INDEX_PATH = "META-INF/sisu/javax.inject.Named";
  
      private final ArrayList<String> indexEntries = new ArrayList<>();
  
      private long time = Long.MIN_VALUE;
  
      @Override
      public boolean canTransformResource(final String resource) {
          return resource.equals(SISU_INDEX_PATH);
      }
  
      @Override
      public void processResource(
              final String resource, final InputStream is, final List<Relocator> relocators, long time)
              throws IOException {
          Scanner scanner = new Scanner(is, StandardCharsets.UTF_8.name());
          while (scanner.hasNextLine()) {
              String relContent = scanner.nextLine();
              for (Relocator relocator : relocators) {
                  if (relocator.canRelocateClass(relContent)) {
                      relContent = relocator.applyToSourceContent(relContent);
                  }
              }
              indexEntries.add(relContent);
          }
  
          if (time > this.time) {
              this.time = time;
          }
      }
  
      @Override
      public boolean hasTransformedResource() {
          return !indexEntries.isEmpty();
      }
  
      @Override
      public void modifyOutputStream(final JarOutputStream jos) throws IOException {
          JarEntry jarEntry = new JarEntry(SISU_INDEX_PATH);
          jarEntry.setTime(time);
          jos.putNextEntry(jarEntry);
          IOUtils.writeLines(indexEntries, "\n", jos, StandardCharsets.UTF_8);
          jos.flush();
          indexEntries.clear();
      }
  }