package org.apache.maven.plugin.coreit;
   
   /*
    * 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.
   */
  
  import org.apache.maven.execution.MavenSession;
  import org.apache.maven.plugin.AbstractMojo;
  import org.apache.maven.plugin.MojoExecutionException;
  import org.apache.maven.toolchain.ToolchainManagerPrivate;
  import org.apache.maven.toolchain.ToolchainPrivate;
  
  import java.io.File;
  import java.io.FileOutputStream;
  import java.io.IOException;
  import java.io.OutputStream;
  import java.lang.reflect.InvocationTargetException;
  import java.lang.reflect.Method;
  import java.util.Arrays;
  import java.util.Iterator;
  import java.util.Properties;
  
  /**
   * @goal toolchain
   * @phase validate
   */
  public class CoreItMojo
      extends AbstractMojo
  {
  
      /**
       * @component
       */
      private ToolchainManagerPrivate toolchainManager;
  
      /**
       * The current Maven session holding the selected toolchain.
       *
       * @parameter default-value="${session}"
       * @required
       * @readonly
       */
      private MavenSession session;
  
      /**
       * The path to the output file for the properties.
       *
       * @parameter property="toolchain.outputFile" default-value="${project.build.directory}/toolchains.properties"
       */
      private File outputFile;
  
      /**
       * The type identifier of the toolchain, e.g. "jdk".
       *
       * @parameter property="toolchain.type"
       */
      private String type;
  
      /**
       * The name of the tool, e.g. "javac".
       *
       * @parameter property="toolchain.tool"
       */
      private String tool;
  
      /**
       * The zero-based index of the toolchain to select and store in the build context.
       *
       * @parameter property="toolchain.selected"
       */
      private int selected;
  
      public void execute()
          throws MojoExecutionException
      {
          ToolchainPrivate[] tcs = getToolchains();
  
          getLog().info( "[MAVEN-CORE-IT-LOG] Toolchains in plugin: " + Arrays.asList( tcs ) );
  
          if ( selected >= 0 )
          {
              if ( selected < tcs.length )
              {
                  ToolchainPrivate toolchain = tcs[selected];
                 toolchainManager.storeToolchainToBuildContext( toolchain, session );
             }
             else
             {
                 getLog().warn(
                     "[MAVEN-CORE-IT-LOG] Toolchain #" + selected + " can't be selected, found only " + tcs.length );
             }
         }
 
         Properties properties = new Properties();
 
         int count = 1;
         for ( Iterator<ToolchainPrivate> i = Arrays.<ToolchainPrivate>asList( tcs ).iterator(); i.hasNext(); count++ )
         {
             ToolchainPrivate toolchain = i.next();
 
             String foundTool = toolchain.findTool( tool );
             if ( foundTool != null )
             {
                 properties.setProperty( "tool." + count, foundTool );
             }
         }
 
         OutputStream out = null;
         try
         {
             outputFile.getParentFile().mkdirs();
             out = new FileOutputStream( outputFile );
             properties.store( out, "MAVEN-CORE-IT-LOG" );
         }
         catch ( IOException e )
         {
             throw new MojoExecutionException( e.getMessage(), e );
         }
         finally
         {
             if ( out != null )
             {
                 try
                 {
                     out.close();
                 }
                 catch ( IOException e )
                 {
                     // ignore
                 }
             }
         }
     }
 
     private ToolchainPrivate[] getToolchains()
         throws MojoExecutionException
     {
         Class<? extends ToolchainManagerPrivate> managerClass = toolchainManager.getClass();
 
         try
         {
             try
             {
                 // try 2.x style API
                 Method oldMethod = managerClass.getMethod( "getToolchainsForType", new Class[]{ String.class } );
 
                 return (ToolchainPrivate[]) oldMethod.invoke( toolchainManager, new Object[]{ type } );
             }
             catch ( NoSuchMethodException e )
             {
                 // try 3.x style API
                 Method newMethod =
                     managerClass.getMethod( "getToolchainsForType", new Class[]{ String.class, MavenSession.class } );
 
                 return (ToolchainPrivate[]) newMethod.invoke( toolchainManager, new Object[]{ type, session } );
             }
         }
         catch ( NoSuchMethodException | InvocationTargetException | IllegalAccessException e )
         {
             throw new MojoExecutionException( "Incompatible toolchain API", e );
         }
     }
 
 }