package org.apache.maven.scm.provider.git.command.checkout;
   
   /*
    * 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.IOException;
  import java.io.OutputStream;
  import java.io.Writer;
  import java.nio.file.FileSystem;
  import java.nio.file.Files;
  import java.nio.file.Path;
  import java.nio.file.attribute.PosixFilePermissions;
  import java.security.GeneralSecurityException;
  import java.security.KeyPair;
  import java.security.PublicKey;
  import java.util.ArrayList;
  import java.util.List;
  
  import org.apache.maven.scm.provider.ScmProviderRepositoryWithHost;
  import org.apache.maven.scm.provider.git.GitScmTestUtils;
  import org.apache.maven.scm.repository.ScmRepository;
  import org.apache.maven.scm.tck.command.checkout.CheckOutCommandTckTest;
  import org.apache.sshd.common.config.keys.KeyUtils;
  import org.apache.sshd.common.config.keys.writer.openssh.OpenSSHKeyEncryptionContext;
  import org.apache.sshd.common.config.keys.writer.openssh.OpenSSHKeyPairResourceWriter;
  import org.apache.sshd.git.GitLocationResolver;
  import org.apache.sshd.git.pack.GitPackCommandFactory;
  import org.apache.sshd.server.SshServer;
  import org.apache.sshd.server.auth.pubkey.KeySetPublickeyAuthenticator;
  import org.apache.sshd.server.auth.pubkey.PublickeyAuthenticator;
  import org.apache.sshd.server.session.ServerSession;
  import org.apache.sshd.util.test.CommonTestSupportUtils;
  import org.apache.sshd.util.test.CoreTestSupportUtils;
  import org.bouncycastle.openssl.PKCS8Generator;
  import org.bouncycastle.openssl.jcajce.JcaPEMWriter;
  import org.bouncycastle.openssl.jcajce.JcaPKCS8Generator;
  import org.bouncycastle.util.io.pem.PemObject;
  import org.junit.Assume;
  import org.junit.Rule;
  import org.junit.Test;
  import org.junit.rules.TemporaryFolder;
  
  /**
   *
   */
  public abstract class GitSshCheckOutCommandTckTest
      extends CheckOutCommandTckTest
  {
      protected final SshServer sshServer;
      protected final KeyPair keyPair;
      protected final List<PublicKey> acceptedPublicKeys;
  
      @Rule
      public TemporaryFolder tmpDirectory = new TemporaryFolder();
  
      protected GitSshCheckOutCommandTckTest() throws GeneralSecurityException
      {
           sshServer = CoreTestSupportUtils.setupTestServer( getClass() );
           keyPair = CommonTestSupportUtils.generateKeyPair( KeyUtils.RSA_ALGORITHM, 2048 );
           acceptedPublicKeys = new ArrayList<>();
           acceptedPublicKeys.add( keyPair.getPublic() );
           PublickeyAuthenticator authenticator = new KeySetPublickeyAuthenticator( "onlykey",
                    acceptedPublicKeys );
           sshServer.setPublickeyAuthenticator( authenticator );
      }
  
      void writePrivateKeyAsPkcs8( Path file, String passphrase )
              throws IOException, GeneralSecurityException
      {
          // encryption only optional
          if ( passphrase != null )
          {
              // encryption with format outlined in https://dnaeon.github.io/openssh-private-key-binary-format/
              OpenSSHKeyPairResourceWriter writer = new OpenSSHKeyPairResourceWriter();
              OpenSSHKeyEncryptionContext context = new OpenSSHKeyEncryptionContext();
              context.setCipherType( "192" );
              context.setPassword( passphrase );
              try ( OutputStream output = Files.newOutputStream( file ) )
              {
                  writer.writePrivateKey( keyPair, "comment", context, output );
              }
          }
          else
         {
             // wrap unencrypted private key as regular PKCS8 private key
             PKCS8Generator pkcs8Generator = new JcaPKCS8Generator( keyPair.getPrivate(), null );
             PemObject pemObject = pkcs8Generator.generate();
 
             try ( Writer writer = Files.newBufferedWriter( file );
                             JcaPEMWriter pw = new JcaPEMWriter( writer ) )
             {
                 pw.writeObject( pemObject );
             }
         }
 
         if ( file.getFileSystem().supportedFileAttributeViews().contains( "posix" ) )
         {
             // must only be readable/writeable by me
             Files.setPosixFilePermissions( file, PosixFilePermissions.fromString( "rwx------" ) );
         }
     }
 
     protected abstract String getScmProvider();
 
     /** {@inheritDoc} */
     public String getScmUrl()
         throws Exception
     {
         return "scm:" + getScmProvider() + ":ssh://localhost:" + sshServer.getPort() + "/repository";
     }
 
     public void configureCredentials( ScmRepository repository, String passphrase )
         throws Exception
     {
         ScmProviderRepositoryWithHost providerRepository =
              ScmProviderRepositoryWithHost.class.cast( repository.getProviderRepository() );
         // store as file
         Path privateKeyFile = tmpDirectory.newFile().toPath();
         writePrivateKeyAsPkcs8( privateKeyFile, passphrase );
         providerRepository.setPrivateKey( privateKeyFile.toString() );
         providerRepository.setPassphrase( passphrase ); // may be null
     }
 
     /** {@inheritDoc} */
     public void initRepo()
         throws Exception
     {
         GitScmTestUtils.initRepo( "src/test/resources/repository/", getRepositoryRoot(), getWorkingDirectory() );
 
         GitLocationResolver gitLocationResolver = new GitLocationResolver()
         {
             @Override
             public Path resolveRootDirectory( String command, String[] args, ServerSession session, FileSystem fs )
                 throws IOException
             {
                 return getRepositoryRoot().getParentFile().toPath();
             }
         };
         sshServer.setCommandFactory( new GitPackCommandFactory( gitLocationResolver ) );
         sshServer.start();
 
         // as checkout also already happens in setup() make sure to configure credentials here as well
         configureCredentials( getScmRepository(), null );
     }
 
     @Override
     public void removeRepo() throws Exception
     {
         sshServer.stop();
         super.removeRepo();
     }
 
     @Override
     @Test
     public void testCheckOutCommandTest()
         throws Exception
     {
         configureCredentials( getScmRepository(), null );
         super.testCheckOutCommandTest();
     }
 
     @Test
     public void testCheckOutCommandWithPassphraseTest() throws Exception
     {
         // TODO: currently no easy way to pass passphrase in gitexe
         Assume.assumeTrue( "Ignore test with passphrase for provider " + getScmProvider(),
                            "jgit".equals( getScmProvider() ) );
         configureCredentials( getScmRepository(), "mySecret" );
         super.testCheckOutCommandTest();
     }
 }