/*
    * Copyright (C) 2011, Chris Aniszczyk <caniszczyk@gmail.com> 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.Collection;
  
  import org.eclipse.jgit.api.errors.GitAPIException;
  import org.eclipse.jgit.api.errors.InvalidRefNameException;
  import org.eclipse.jgit.api.errors.RefNotFoundException;
  import org.eclipse.jgit.internal.JGitText;
  import org.eclipse.jgit.lib.Constants;
  import org.eclipse.jgit.lib.ReflogEntry;
  import org.eclipse.jgit.lib.ReflogReader;
  import org.eclipse.jgit.lib.Repository;
  
  /**
   * The reflog command
   *
   * @see <a
   *      href="http://www.kernel.org/pub/software/scm/git/docs/git-reflog.html"
   *      >Git documentation about reflog</a>
   */
  public class ReflogCommand extends GitCommand<Collection<ReflogEntry>> {
  
  	private String ref = Constants.HEAD;
  
  	/**
  	 * Constructor for ReflogCommand.
  	 *
  	 * @param repo
  	 *            the {@link org.eclipse.jgit.lib.Repository}
  	 */
  	public ReflogCommand(Repository repo) {
  		super(repo);
  	}
  
  	/**
  	 * The ref used for the reflog operation. If no ref is set, the default
  	 * value of HEAD will be used.
  	 *
  	 * @param ref
  	 *            the name of the {@code Ref} to log
  	 * @return {@code this}
  	 */
  	public ReflogCommand setRef(String ref) {
  		checkCallable();
  		this.ref = ref;
  		return this;
  	}
  
  	/**
  	 * {@inheritDoc}
  	 * <p>
  	 * Run the reflog command
  	 */
  	@Override
  	public Collection<ReflogEntry> call() throws GitAPIException,
  			InvalidRefNameException {
  		checkCallable();
  
  		try {
  			ReflogReader reader = repo.getReflogReader(ref);
  			if (reader == null)
  				throw new RefNotFoundException(MessageFormat.format(
  						JGitText.get().refNotResolved, ref));
  			return reader.getReverseEntries();
  		} catch (IOException e) {
  			throw new InvalidRefNameException(MessageFormat.format(
  					JGitText.get().cannotRead, ref), e);
  		}
  	}
  
  }