/*
    * 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.hg.command.update;
  
  import java.io.File;
  import java.util.ArrayList;
  import java.util.List;
  import java.util.Map;
  
  import org.apache.commons.lang3.StringUtils;
  import org.apache.maven.scm.ScmException;
  import org.apache.maven.scm.ScmFile;
  import org.apache.maven.scm.ScmFileSet;
  import org.apache.maven.scm.ScmFileStatus;
  import org.apache.maven.scm.ScmResult;
  import org.apache.maven.scm.ScmVersion;
  import org.apache.maven.scm.command.Command;
  import org.apache.maven.scm.command.changelog.ChangeLogCommand;
  import org.apache.maven.scm.command.update.AbstractUpdateCommand;
  import org.apache.maven.scm.command.update.UpdateScmResult;
  import org.apache.maven.scm.command.update.UpdateScmResultWithRevision;
  import org.apache.maven.scm.provider.ScmProviderRepository;
  import org.apache.maven.scm.provider.hg.HgUtils;
  import org.apache.maven.scm.provider.hg.command.HgCommandConstants;
  import org.apache.maven.scm.provider.hg.command.HgConsumer;
  import org.apache.maven.scm.provider.hg.command.changelog.HgChangeLogCommand;
  import org.apache.maven.scm.provider.hg.command.diff.HgDiffConsumer;
  
  /**
   * @author <a href="mailto:thurner.rupert@ymono.net">thurner rupert</a>
   * @author Olivier Lamy
   */
  public class HgUpdateCommand extends AbstractUpdateCommand implements Command {
      /**
       * {@inheritDoc}
       */
      protected UpdateScmResult executeUpdateCommand(ScmProviderRepository repo, ScmFileSet fileSet, ScmVersion tag)
              throws ScmException {
          File workingDir = fileSet.getBasedir();
  
          String[] updateCmd;
          // Update branch
          if (repo.isPushChanges()) {
              updateCmd = new String[] {
                  HgCommandConstants.PULL_CMD,
                  HgCommandConstants.REVISION_OPTION,
                  tag != null && !StringUtils.isEmpty(tag.getName()) ? tag.getName() : "tip"
              };
          } else {
              updateCmd = new String[] {
                  HgCommandConstants.UPDATE_CMD,
                  tag != null && !StringUtils.isEmpty(tag.getName()) ? tag.getName() : "tip",
                  HgCommandConstants.CLEAN_OPTION
              };
          }
          ScmResult updateResult = HgUtils.execute(new HgConsumer(), workingDir, updateCmd);
  
          if (!updateResult.isSuccess()) {
              return new UpdateScmResult(null, null, updateResult);
          }
  
          // Find changes from last revision
          int currentRevision = HgUtils.getCurrentRevisionNumber(workingDir);
          int previousRevision = currentRevision - 1;
          String[] diffCmd =
                  new String[] {HgCommandConstants.DIFF_CMD, HgCommandConstants.REVISION_OPTION, "" + previousRevision};
          HgDiffConsumer diffConsumer = new HgDiffConsumer(workingDir);
          ScmResult diffResult = HgUtils.execute(diffConsumer, workingDir, diffCmd);
  
          // Now translate between diff and update file status
          List<ScmFile> updatedFiles = new ArrayList<>();
          List<CharSequence> changes = new ArrayList<>();
          List<ScmFile> diffFiles = diffConsumer.getChangedFiles();
          Map<String, CharSequence> diffChanges = diffConsumer.getDifferences();
          for (ScmFile file : diffFiles) {
              changes.add(diffChanges.get(file.getPath()));
              if (file.getStatus() == ScmFileStatus.MODIFIED) {
                  updatedFiles.add(new ScmFile(file.getPath(), ScmFileStatus.PATCHED));
              } else {
                  updatedFiles.add(file);
              }
          }
  
         if (repo.isPushChanges()) {
             String[] hgUpdateCmd = new String[] {HgCommandConstants.UPDATE_CMD};
             HgUtils.execute(new HgConsumer(), workingDir, hgUpdateCmd);
         }
 
         return new UpdateScmResultWithRevision(
                 updatedFiles, new ArrayList<>(0), String.valueOf(currentRevision), diffResult);
     }
 
     protected ChangeLogCommand getChangeLogCommand() {
         return new HgChangeLogCommand();
     }
 }