/*
    * 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.toolchain.jdk;
  
  import javax.inject.Inject;
  
  import java.io.IOException;
  import java.io.StringWriter;
  import java.io.Writer;
  import java.nio.file.Files;
  import java.nio.file.Path;
  import java.nio.file.Paths;
  
  import org.apache.maven.plugin.AbstractMojo;
  import org.apache.maven.plugin.MojoFailureException;
  import org.apache.maven.plugins.annotations.Mojo;
  import org.apache.maven.plugins.annotations.Parameter;
  import org.apache.maven.toolchain.model.PersistedToolchains;
  import org.apache.maven.toolchain.model.io.xpp3.MavenToolchainsXpp3Writer;
  
  /**
   * Run the JDK toolchain discovery mechanism and generates a toolchains XML.
   *
   * @since 3.2.0
   */
  @Mojo(name = "generate-jdk-toolchains-xml", requiresProject = false)
  public class GenerateJdkToolchainsXmlMojo extends AbstractMojo {
  
      /**
       * The path and name pf the toolchain XML file that will be generated.
       * If not provided, the XML will be written to the standard output.
       */
      @Parameter(property = "toolchain.file")
      String file;
  
      /**
       * Toolchain discoverer
       */
      @Inject
      ToolchainDiscoverer discoverer;
  
      @Override
      public void execute() throws MojoFailureException {
          try {
              PersistedToolchains toolchains = discoverer.discoverToolchains();
              if (file != null) {
                  Path file = Paths.get(this.file).toAbsolutePath();
                  Files.createDirectories(file.getParent());
                  try (Writer writer = Files.newBufferedWriter(file)) {
                      new MavenToolchainsXpp3Writer().write(writer, toolchains);
                  }
              } else {
                  StringWriter writer = new StringWriter();
                  new MavenToolchainsXpp3Writer().write(writer, toolchains);
                  System.out.println(writer);
              }
          } catch (IOException e) {
              throw new MojoFailureException("Unable to generate toolchains.xml", e);
          }
      }
  }