package org.apache.maven.scm.provider.perforce.command;
   
   /*
    * 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.scm.CommandParameters;
  import org.apache.maven.scm.ScmException;
  import org.apache.maven.scm.ScmFileSet;
  import org.apache.maven.scm.ScmResult;
  import org.apache.maven.scm.command.AbstractCommand;
  import org.apache.maven.scm.log.ScmLogger;
  import org.apache.maven.scm.provider.ScmProviderRepository;
  import org.apache.maven.scm.provider.perforce.PerforceScmProvider;
  import org.apache.maven.scm.provider.perforce.repository.PerforceScmProviderRepository;
  import org.codehaus.plexus.util.IOUtil;
  import org.codehaus.plexus.util.cli.CommandLineException;
  import org.codehaus.plexus.util.cli.Commandline;
  
  import java.io.BufferedReader;
  import java.io.IOException;
  import java.io.InputStreamReader;
  import java.util.HashMap;
  import java.util.Map;
  
  /**
   * Encapsulates the 'p4 info' command which can be very useful in determining
   * the runtime environment.  Use <code>getEntry(String key)</code> to query
   * the info set for a particular property.  The data from p4 info looks like this:
   * <p/>
   * <pre>
   * User name: mperham
   * Client name: mikeperham-dt
   * Client host: mikeperham-dt
   * Client root: d:\perforce
   * </pre>
   * <p/>
   * where the key is the content before the first colon and the value is the data after
   * the first colon, trimmed.  For example:
   * <code>PerforceInfoCommand.getInfo( this, repo ).getEntry( "User name" )</code>
   * <p/>
   * Note that this is not a traditional SCM command.  This uses the Command class
   * simply because it needs a logger for error handling and the current repository data for
   * command line creation.
   *
   * @author mperham
   * @version $Id: $
   */
  public class PerforceInfoCommand
      extends AbstractCommand
      implements PerforceCommand
  {
      private static PerforceInfoCommand singleton = null;
  
      private Map<String, String> entries = null;
  
      public static PerforceInfoCommand getInfo( ScmLogger logger, PerforceScmProviderRepository repo )
      {
          return getSingleton( logger, repo );
      }
  
      public String getEntry( String key )
      {
          return (String) entries.get( key );
      }
  
      private static synchronized PerforceInfoCommand getSingleton( ScmLogger logger, PerforceScmProviderRepository repo )
      {
          if ( singleton == null )
          {
              PerforceInfoCommand pic = new PerforceInfoCommand();
              if ( logger != null )
              {
                  pic.setLogger( logger );
              }
              try
              {
                  pic.executeCommand( repo, null, null );
                  singleton = pic;
              }
              catch ( ScmException e )
              {
                  if ( pic.getLogger().isErrorEnabled() )
                  {
                     pic.getLogger().error( "ScmException " + e.getMessage(), e );
                 }
             }
         }
 
         return singleton;
     }
 
     /**
      * {@inheritDoc}
      */
     protected ScmResult executeCommand( ScmProviderRepository repo, ScmFileSet scmFileSet,
                                         CommandParameters commandParameters )
         throws ScmException
     {
         if ( !PerforceScmProvider.isLive() )
         {
             return null;
         }
         InputStreamReader isReader = null;
         try
         {
             Commandline command = PerforceScmProvider.createP4Command( (PerforceScmProviderRepository) repo, null );
             command.createArg().setValue( "info" );
             if ( getLogger().isDebugEnabled() )
             {
                 getLogger().debug( PerforceScmProvider.clean( "Executing: " + command.toString() ) );
             }
             Process proc = command.execute();
             isReader = new InputStreamReader( proc.getInputStream() );
             BufferedReader br = new BufferedReader( isReader );
             String line;
             entries = new HashMap<String, String>();
             while ( ( line = br.readLine() ) != null )
             {
                 int idx = line.indexOf( ':' );
                 if ( idx == -1 )
                 {
                     if ( line.indexOf( "Client unknown." ) == -1 )
                     {
                         throw new IllegalStateException( "Unexpected results from 'p4 info' command: " + line );
                     }
 
                     if ( getLogger().isDebugEnabled() )
                     {
                         getLogger().debug( "Cannot find client." );
                     }
                     entries.put( "Client root", "" );
                 }
                 else
                 {
                     String key = line.substring( 0, idx );
                     String value = line.substring( idx + 1 ).trim();
                     entries.put( key, value );
                 }
             }
         }
         catch ( CommandLineException e )
         {
             throw new ScmException( e.getLocalizedMessage() );
         }
         catch ( IOException e )
         {
             throw new ScmException( e.getLocalizedMessage() );
         }
         finally
         {
             IOUtil.close( isReader );
         }
         return null;
     }
 }