/*
    * 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.
   */
  package org.apache.maven.scm.provider.git.gitexe.command;
  
  import java.io.File;
  import java.io.IOException;
  import java.util.HashMap;
  import java.util.List;
  import java.util.Map;
  
  import org.apache.commons.io.FilenameUtils;
  import org.apache.commons.lang3.StringUtils;
  import org.apache.maven.scm.ScmException;
  import org.apache.maven.scm.provider.git.repository.GitScmProviderRepository;
  import org.apache.maven.scm.provider.git.util.GitUtil;
  import org.apache.maven.scm.providers.gitlib.settings.Settings;
  import org.codehaus.plexus.util.cli.CommandLineException;
  import org.codehaus.plexus.util.cli.CommandLineUtils;
  import org.codehaus.plexus.util.cli.Commandline;
  import org.codehaus.plexus.util.cli.StreamConsumer;
  import org.slf4j.Logger;
  import org.slf4j.LoggerFactory;
  
  /**
   * Command line construction utility.
   *
   * @author Brett Porter
   * @author <a href="mailto:struberg@yahoo.de">Mark Struberg</a>
   */
  public final class GitCommandLineUtils {
      private static final Logger LOGGER = LoggerFactory.getLogger(GitCommandLineUtils.class);
  
      // https://git-scm.com/docs/git#Documentation/git.txt-codeGITSSHCOMMANDcode, requires git 2.3.0 or newer
      public static final String VARIABLE_GIT_SSH_COMMAND = "GIT_SSH_COMMAND";
  
      private GitCommandLineUtils() {}
  
      public static void addTarget(Commandline commandLine, List<File> files) {
          if (files == null || files.isEmpty()) {
              return;
          }
          final File workingDirectory = commandLine.getWorkingDirectory();
          try {
              final String canonicalWorkingDirectory = workingDirectory.getCanonicalPath();
              for (File file : files) {
                  String relativeFile = file.getPath();
  
                  final String canonicalFile = file.getCanonicalPath();
                  if (canonicalFile.startsWith(canonicalWorkingDirectory)) {
                      // so we can omit the starting characters
                      relativeFile = canonicalFile.substring(canonicalWorkingDirectory.length());
  
                      if (relativeFile.startsWith(File.separator)) {
                          relativeFile = relativeFile.substring(File.separator.length());
                      }
                  }
  
                  // no setFile() since this screws up the working directory!
                  commandLine.createArg().setValue(FilenameUtils.separatorsToUnix(relativeFile));
              }
          } catch (IOException ex) {
              throw new IllegalArgumentException(
                      "Could not get canonical paths for workingDirectory = " + workingDirectory + " or files=" + files,
                      ex);
          }
      }
  
      /**
       * Use this only for commands not requiring environment variables (i.e. local commands).
       */
      public static Commandline getBaseGitCommandLine(File workingDirectory, String command) {
          return getBaseGitCommandLine(workingDirectory, command, null, null);
      }
  
      /**
       * Use this for commands requiring environment variables (i.e. remote commands).
       */
      public static Commandline getBaseGitCommandLine(
              File workingDirectory,
              String command,
              GitScmProviderRepository repository,
              Map<String, String> environment) {
          Commandline commandLine = getAnonymousBaseGitCommandLine(workingDirectory, command);
         if (repository != null) {
             prepareEnvVariablesForRepository(repository, environment).forEach(commandLine::addEnvironment);
         } else if (environment != null) {
             environment.forEach(commandLine::addEnvironment);
         }
         return commandLine;
     }
 
     /**
      * Creates a {@link Commandline} for which toString() does not display
      * the password.
      *
      * @param workingDirectory
      * @param command
      * @return CommandLine with anonymous output
      */
     private static Commandline getAnonymousBaseGitCommandLine(File workingDirectory, String command) {
         if (command == null || command.isEmpty()) {
             return null;
         }
 
         Commandline commandLine = new AnonymousCommandLine();
 
         composeCommand(workingDirectory, command, commandLine);
 
         return commandLine;
     }
 
     private static void composeCommand(File workingDirectory, String command, Commandline commandLine) {
         Settings settings = GitUtil.getSettings();
 
         commandLine.setExecutable(settings.getGitCommand());
 
         commandLine.createArg().setValue(command);
 
         if (workingDirectory != null) {
             commandLine.setWorkingDirectory(workingDirectory.getAbsolutePath());
         }
     }
 
     public static int execute(
             Commandline commandline, StreamConsumer consumer, CommandLineUtils.StringStreamConsumer stderr)
             throws ScmException {
         if (LOGGER.isDebugEnabled()) {
             LOGGER.debug("Executing: " + commandline);
             LOGGER.debug(
                     "Working directory: " + commandline.getWorkingDirectory().getAbsolutePath());
         }
 
         int exitCode;
         try {
             exitCode = CommandLineUtils.executeCommandLine(commandline, consumer, stderr);
         } catch (CommandLineException ex) {
             throw new ScmException("Error while executing command.", ex);
         }
 
         return exitCode;
     }
 
     public static int execute(
             Commandline commandLine,
             CommandLineUtils.StringStreamConsumer stdout,
             CommandLineUtils.StringStreamConsumer stderr)
             throws ScmException {
         if (LOGGER.isDebugEnabled()) {
             LOGGER.debug("Executing: " + commandLine);
             LOGGER.debug(
                     "Working directory: " + commandLine.getWorkingDirectory().getAbsolutePath());
         }
 
         int exitCode;
         try {
             exitCode = CommandLineUtils.executeCommandLine(commandLine, stdout, stderr);
         } catch (CommandLineException ex) {
             throw new ScmException("Error while executing command.", ex);
         }
 
         return exitCode;
     }
 
     static Map<String, String> prepareEnvVariablesForRepository(
             GitScmProviderRepository repository, Map<String, String> environmentVariables) {
         Map<String, String> effectiveEnvironmentVariables = new HashMap<>();
         if (environmentVariables != null) {
             effectiveEnvironmentVariables.putAll(environmentVariables);
         }
         if (StringUtils.isNotBlank(repository.getPrivateKey())) {
             if (effectiveEnvironmentVariables.putIfAbsent(
                             VARIABLE_GIT_SSH_COMMAND,
                             "ssh -o IdentitiesOnly=yes -i "
                                     + FilenameUtils.separatorsToUnix(repository.getPrivateKey()))
                     != null) {
                 LOGGER.warn(
                         "Ignore GitScmProviderRepository.privateKey as environment variable {} is already set",
                         VARIABLE_GIT_SSH_COMMAND);
             }
         }
         if (StringUtils.isNotBlank(repository.getPassphrase())) {
             LOGGER.warn("GitScmProviderRepository.passphrase currently not supported by provider 'git'");
         }
         return effectiveEnvironmentVariables;
     }
 }