package org.apache.maven.wagon.providers.ssh.knownhost;

 /*

  * 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 java.io.ByteArrayInputStream;

 import java.io.File;

 import java.io.FileInputStream;

 import java.io.IOException;

 import java.io.InputStream;

 import java.util.Set;

 import org.codehaus.plexus.util.FileUtils;

 /**

  * Provides known hosts from a file

  *

  * @author Juan F. Codagnone

  * @since Sep 12, 2005

  * 

  * @plexus.component role="org.apache.maven.wagon.providers.ssh.knownhost.KnownHostsProvider"

  *    role-hint="file"

  *    instantiation-strategy="per-lookup"

  */

 public class FileKnownHostsProvider

     extends StreamKnownHostsProvider

 {

     private final File file;

     /**

      * Creates the FileKnownHostsProvider.

      *

      * @param file the file that holds the known hosts, in the openssh format

      * @throws IOException

      */

     public FileKnownHostsProvider( File file )

         throws IOException

     {

         super( file.exists() ? (InputStream) new FileInputStream( file ) : new ByteArrayInputStream( "".getBytes() ) );

         this.file = file;

     }

     /**

      * Creates a FileKnownHostsProvider using as file openssh knwon_host

      *

      * @throws IOException

      * @see #FileKnownHostsProvider(File)

      */

     public FileKnownHostsProvider()

         throws IOException

     {

         this( new File( System.getProperty( "user.home" ), ".ssh/known_hosts" ) );

     }

     public void storeKnownHosts( String contents )

         throws IOException

     {

         Set<KnownHostEntry> hosts = this.loadKnownHosts( contents );

         if ( ! this.knownHosts.equals( hosts ) )

         {

             file.getParentFile().mkdirs();

             FileUtils.fileWrite( file.getAbsolutePath(), contents );

             this.knownHosts = hosts;

         }

     }

     public File getFile()

     {

         return file;

     }

 }