package org.apache.maven.shared.utils.cli.javatool;
   
   /*
    * 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.shared.utils.Os;
  import org.apache.maven.shared.utils.StringUtils;
  import org.apache.maven.shared.utils.cli.CommandLineException;
  import org.apache.maven.shared.utils.cli.CommandLineUtils;
  import org.apache.maven.shared.utils.cli.Commandline;
  import org.apache.maven.shared.utils.cli.StreamConsumer;
  import org.codehaus.plexus.logging.AbstractLogEnabled;
  
  import java.io.File;
  import java.io.InputStream;
  import java.lang.reflect.InvocationTargetException;
  import java.lang.reflect.Method;
  import java.util.Map;
  
  /**
   * Abstract implementation of a {@link JavaTool}.
   *
   * @author Tony Chemit <chemit@codelutin.com>
   * @since 0.5
   * @param <Request>
   */
  public abstract class AbstractJavaTool<Request extends JavaToolRequest>
      extends AbstractLogEnabled
      implements JavaTool<Request>
  {
  
      /**
       * The java tool name to find out in the jdk.
       */
      private final String javaToolName;
  
      /**
       * The location of the java tool executable file.
       */
      private String javaToolFile;
  
      /**
       * Optional toolChain used to find java tool executable file.
       */
      private Object toolchain;
  
      /**
       * @param javaToolName The name of the java tool.
       */
      protected AbstractJavaTool( String javaToolName )
      {
          this.javaToolName = javaToolName;
      }
  
      /**
       * Create the command line object given the request.
       *
       * @param request      User request on the java tool
       * @param javaToolFileLocation Location of the java tool file to use
       * @return the command line
       * @throws JavaToolException if could not create the command line from the request
       */
      protected abstract Commandline createCommandLine( Request request, String javaToolFileLocation )
          throws JavaToolException;
  
      /**
       * {@inheritDoc}
       */
      public String getJavaToolName()
      {
          return javaToolName;
      }
  
      /**
       * {@inheritDoc}
       */
      public void setToolchain( Object toolchain )
      {
          this.toolchain = toolchain;
      }
  
      /**
       * {@inheritDoc}
      */
     public JavaToolResult execute( Request request )
         throws JavaToolException
     {
 
         if ( javaToolFile == null )
         {
 
             // find the java tool file to use
             try
             {
                 javaToolFile = findJavaToolExecutable();
             }
             catch ( Exception e )
             {
                 throw new JavaToolException( "Error finding " + javaToolName + " executable. Reason: " + e.getMessage(),
                                              e );
             }
         }
 
         // creates the command line from the given request
         Commandline cli = createCommandLine( request, javaToolFile );
 
         // execute it
         JavaToolResult result = executeCommandLine( cli, request );
 
         // return result
         return result;
     }
 
     /**
      * @return {@link InputStream}
      */
     protected InputStream createSystemInputStream()
     {
         InputStream systemIn = new InputStream()
         {
 
             /**
              * {@inheritDoc}
              */
             public int read()
             {
                 return -1;
             }
 
         };
         return systemIn;
     }
 
     /**
      * @param cli {@link Commandline}
      * @param request The request.
      * @return {@link JavaToolRequest}
      */
     protected JavaToolResult executeCommandLine( Commandline cli, Request request )
     {
         if ( getLogger().isDebugEnabled() )
         {
             getLogger().debug( "Executing: " + cli );
         }
 
         JavaToolResult result = createResult();
 
         result.setCommandline( cli );
 
         InputStream systemIn = createSystemInputStream();
 
         StreamConsumer systemOut = createSystemOutStreamConsumer( request );
 
         StreamConsumer systemErr = createSystemErrorStreamConsumer( request );
 
         try
         {
             int resultCode = CommandLineUtils.executeCommandLine( cli, systemIn, systemOut, systemErr );
 
             result.setExitCode( resultCode );
         }
         catch ( CommandLineException e )
         {
             result.setExecutionException( e );
         }
 
         return result;
     }
 
     /**
      * @param request The request.
      * @return {@link StreamConsumer}
      */
     protected StreamConsumer createSystemErrorStreamConsumer( Request request )
     {
         StreamConsumer systemErr = request.getSystemErrorStreamConsumer();
 
         if ( systemErr == null )
         {
             systemErr = new StreamConsumer()
             {
 
                 /**
                  * {@inheritDoc}
                  */
                 public void consumeLine( final String line )
                 {
                     getLogger().warn( line );
                 }
 
             };
         }
         return systemErr;
     }
 
     /**
      * @param request The request.
      * @return {@link StreamConsumer}
      */
     protected StreamConsumer createSystemOutStreamConsumer( Request request )
     {
         StreamConsumer systemOut = request.getSystemOutStreamConsumer();
 
         if ( systemOut == null )
         {
 
             systemOut = new StreamConsumer()
             {
 
                 /**
                  * {@inheritDoc}
                  */
                 public void consumeLine( final String line )
                 {
                     getLogger().info( line );
 
                 }
 
             };
         }
         return systemOut;
     }
 
     /**
      * @return The JavaToolResult.
      */
     protected JavaToolResult createResult()
     {
         return new JavaToolResult();
     }
 
     /**
      * @return The location of the java tool executable.
      */
     protected String findJavaToolExecutable()
     {
         String executable = null;
 
         if ( toolchain != null )
         {
             executable = findToolchainExecutable();
         }
 
         String command = javaToolName + ( Os.isFamily( Os.FAMILY_WINDOWS ) ? ".exe" : "" );
 
         if ( executable == null )
         {
             executable = findExecutable( command, System.getProperty( "java.home" ), "../bin", "bin", "../sh" );
         }
 
         if ( executable == null )
         {
 
             Map<String, String> env = System.getenv();
 
             String[] variables = { "JDK_HOME", "JAVA_HOME" };
 
             for ( String variable : variables )
             {
                 executable = findExecutable( command, env.get( variable ), "bin", "sh" );
                 if ( executable != null )
                 {
                     break;
                 }
             }
         }
 
         if ( executable == null )
         {
             executable = command;
         }
 
         return executable;
     }
 
     /**
      * Run toolchain.findTool( javaToolName ); through reflection to avoid compile dependency on
      * Maven core.
      */
     private String findToolchainExecutable()
     {
         try
         {
             Method m = toolchain.getClass().getMethod( "findTool", String.class );
             return (String) m.invoke( toolchain, javaToolName );
         }
         catch ( NoSuchMethodException e )
         {
             // should not happen if toolchain is really a Toolchain object
             getLogger().warn( "unexpected NoSuchMethodException", e );
         }
         catch ( SecurityException e )
         {
             // should not happen
             getLogger().warn( "unexpected SecurityException", e );
         }
         catch ( IllegalAccessException e )
         {
             // should not happen
             getLogger().warn( "unexpected IllegalAccessException", e );
         }
         catch ( IllegalArgumentException e )
         {
             // should not happen: parameter is the right type
             getLogger().warn( "unexpected IllegalArgumentException", e );
         }
         catch ( InvocationTargetException e )
         {
             // not expected...
             getLogger().warn( "unexpected InvocationTargetException", e );
         }
         return null;
     }
 
     /**
      * Finds the specified command in any of the given sub directories of the specified JDK/JRE home directory.
      *
      * @param command The command to find, must not be <code>null</code>.
      * @param homeDir The home directory to search in, may be <code>null</code>.
      * @param subDirs The sub directories of the home directory to search in, must not be <code>null</code>.
      * @return The (absolute) path to the command if found, <code>null</code> otherwise.
      */
     private String findExecutable( String command, String homeDir, String... subDirs )
     {
         String result = null;
         if ( StringUtils.isNotEmpty( homeDir ) )
         {
             for ( String subDir : subDirs )
             {
                 File file = new File( new File( homeDir, subDir ), command );
 
                 if ( file.isFile() )
                 {
                     result = file.getAbsolutePath();
                     break;
                 }
             }
         }
 
         return result;
     }
 }