/*
    * Copyright (C) 2011, GitHub Inc. and others
    *
    * This program and the accompanying materials are made available under the
    * terms of the Eclipse Distribution License v. 1.0 which is available at
    * https://www.eclipse.org/org/documents/edl-v10.php.
    *
    * SPDX-License-Identifier: BSD-3-Clause
    */
  package org.eclipse.jgit.api;
  
  import java.io.IOException;
  import java.text.MessageFormat;
  import java.util.ArrayList;
  import java.util.Collection;
  import java.util.Collections;
  import java.util.List;
  
  import org.eclipse.jgit.api.errors.GitAPIException;
  import org.eclipse.jgit.api.errors.InvalidRefNameException;
  import org.eclipse.jgit.api.errors.JGitInternalException;
  import org.eclipse.jgit.internal.JGitText;
  import org.eclipse.jgit.lib.Constants;
  import org.eclipse.jgit.lib.ReflogEntry;
  import org.eclipse.jgit.lib.Repository;
  import org.eclipse.jgit.revwalk.RevCommit;
  import org.eclipse.jgit.revwalk.RevWalk;
  
  /**
   * Command class to list the stashed commits in a repository.
   *
   * @see <a href="http://www.kernel.org/pub/software/scm/git/docs/git-stash.html"
   *      >Git documentation about Stash</a>
   */
  public class StashListCommand extends GitCommand<Collection<RevCommit>> {
  
  	/**
  	 * Create a new stash list command
  	 *
  	 * @param repo a {@link org.eclipse.jgit.lib.Repository} object.
  	 */
  	public StashListCommand(Repository repo) {
  		super(repo);
  	}
  
  	/** {@inheritDoc} */
  	@Override
  	public Collection<RevCommit> call() throws GitAPIException,
  			InvalidRefNameException {
  		checkCallable();
  
  		try {
  			if (repo.exactRef(Constants.R_STASH) == null)
  				return Collections.emptyList();
  		} catch (IOException e) {
  			throw new InvalidRefNameException(MessageFormat.format(
  					JGitText.get().cannotRead, Constants.R_STASH), e);
  		}
  
  		final ReflogCommand refLog = new ReflogCommand(repo);
  		refLog.setRef(Constants.R_STASH);
  		final Collection<ReflogEntry> stashEntries = refLog.call();
  		if (stashEntries.isEmpty())
  			return Collections.emptyList();
  
  		final List<RevCommit> stashCommits = new ArrayList<>(
  				stashEntries.size());
  		try (RevWalk walk = new RevWalk(repo)) {
  			for (ReflogEntry entry : stashEntries) {
  				try {
  					stashCommits.add(walk.parseCommit(entry.getNewId()));
  				} catch (IOException e) {
  					throw new JGitInternalException(MessageFormat.format(
  							JGitText.get().cannotReadCommit, entry.getNewId()),
  							e);
  				}
  			}
  		}
  		return stashCommits;
  	}
  }