/*
    * 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.plugin.compiler;
  
  import java.util.ArrayList;
  import java.util.HashSet;
  import java.util.List;
  import java.util.Set;
  
  import org.apache.maven.plugin.logging.Log;
  import org.objectweb.asm.ClassReader;
  import org.objectweb.asm.ClassVisitor;
  import org.objectweb.asm.ClassWriter;
  import org.objectweb.asm.ModuleVisitor;
  import org.objectweb.asm.Opcodes;
  
  /**
   * {@code module-info.class} bytecode transformer for
   * <a href="https://issues.apache.org/jira/browse/MCOMPILER-542">MCOMPILER-542</a>:
   * drops detailed JDK version.
   */
  final class ModuleInfoTransformer {
  
      private ModuleInfoTransformer() {}
  
      static byte[] transform(byte[] originalBytecode, String javaVersion, Log log) {
          List<String> modulesModified = new ArrayList<>();
          Set<String> foundVersions = new HashSet<>();
          ClassReader reader = new ClassReader(originalBytecode);
          ClassWriter writer = new ClassWriter(0);
  
          ClassVisitor classVisitor = new ClassVisitor(Opcodes.ASM9, writer) {
              @Override
              public ModuleVisitor visitModule(String name, int access, String version) {
                  ModuleVisitor originalModuleVisitor = super.visitModule(name, access, version);
                  return new ModuleVisitor(Opcodes.ASM9, originalModuleVisitor) {
                      @Override
                      public void visitRequire(String module, int access, String version) {
                          // Check if the module name matches the java/jdk modules
                          if (version != null && (module.startsWith("java.") || module.startsWith("jdk."))) {
                              // Patch the version from the java.* and jdk.* modules
                              // with the --release N version.
                              super.visitRequire(module, access, javaVersion);
                              foundVersions.add(version);
                              modulesModified.add(module);
                          } else {
                              // Keep the original require statement
                              super.visitRequire(module, access, version);
                          }
                      }
                  };
              }
          };
  
          reader.accept(classVisitor, 0);
  
          if (modulesModified.isEmpty()) {
              return null;
          }
  
          log.info(String.format(
                  "JDK-8318913 workaround: patched module-info.class requires version from %s to [%s] on %d JDK modules %s",
                  foundVersions, javaVersion, modulesModified.size(), modulesModified));
  
          return writer.toByteArray();
      }
  }