/*
    * Copyright (C) 2011, GitHub Inc.
    * and other copyright owners as documented in the project's IP log.
    *
    * This program and the accompanying materials are made available
    * under the terms of the Eclipse Distribution License v1.0 which
    * accompanies this distribution, is reproduced below, and is
    * available at http://www.eclipse.org/org/documents/edl-v10.php
    *
   * All rights reserved.
   *
   * Redistribution and use in source and binary forms, with or
   * without modification, are permitted provided that the following
   * conditions are met:
   *
   * - Redistributions of source code must retain the above copyright
   *   notice, this list of conditions and the following disclaimer.
   *
   * - Redistributions in binary form must reproduce the above
   *   copyright notice, this list of conditions and the following
   *   disclaimer in the documentation and/or other materials provided
   *   with the distribution.
   *
   * - Neither the name of the Eclipse Foundation, Inc. nor the
   *   names of its contributors may be used to endorse or promote
   *   products derived from this software without specific prior
   *   written permission.
   *
   * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND
   * CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES,
   * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
   * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
   * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
   * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
   * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
   * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
   * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
   * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
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   * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
   * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
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  package org.eclipse.jgit.api;
  
  import java.io.IOException;
  import java.util.ArrayList;
  import java.util.Collection;
  import java.util.HashMap;
  import java.util.Map;
  
  import org.eclipse.jgit.api.errors.GitAPIException;
  import org.eclipse.jgit.api.errors.JGitInternalException;
  import org.eclipse.jgit.errors.ConfigInvalidException;
  import org.eclipse.jgit.lib.Constants;
  import org.eclipse.jgit.lib.ObjectId;
  import org.eclipse.jgit.lib.Repository;
  import org.eclipse.jgit.submodule.SubmoduleWalk;
  import org.eclipse.jgit.submodule.SubmoduleStatus;
  import org.eclipse.jgit.submodule.SubmoduleStatusType;
  import org.eclipse.jgit.treewalk.filter.PathFilterGroup;
  
  /**
   * A class used to execute a submodule status command.
   *
   * @see <a
   *      href="http://www.kernel.org/pub/software/scm/git/docs/git-submodule.html"
   *      >Git documentation about submodules</a>
   */
  public class SubmoduleStatusCommand extends
  		GitCommand<Map<String, SubmoduleStatus>> {
  
  	private final Collection<String> paths;
  
  	/**
  	 * @param repo
  	 */
  	public SubmoduleStatusCommand(final Repository repo) {
  		super(repo);
  		paths = new ArrayList<String>();
  	}
  
  	/**
  	 * Add repository-relative submodule path to limit status reporting to
  	 *
  	 * @param path
  	 *            (with <code>/</code> as separator)
  	 * @return this command
  	 */
  	public SubmoduleStatusCommand addPath(final String path) {
  		paths.add(path);
  		return this;
  	}
  
  	public Map<String, SubmoduleStatus> call() throws GitAPIException {
  		checkCallable();
  
  		try {
  			SubmoduleWalk generator = SubmoduleWalk.forIndex(repo);
  			if (!paths.isEmpty())
 				generator.setFilter(PathFilterGroup.createFromStrings(paths));
 			Map<String, SubmoduleStatus> statuses = new HashMap<String, SubmoduleStatus>();
 			while (generator.next()) {
 				SubmoduleStatus status = getStatus(generator);
 				statuses.put(status.getPath(), status);
 			}
 			return statuses;
 		} catch (IOException e) {
 			throw new JGitInternalException(e.getMessage(), e);
 		} catch (ConfigInvalidException e) {
 			throw new JGitInternalException(e.getMessage(), e);
 		}
 	}
 
 	private SubmoduleStatus getStatus(SubmoduleWalk generator)
 			throws IOException, ConfigInvalidException {
 		ObjectId id = generator.getObjectId();
 		String path = generator.getPath();
 
 		// Report missing if no path in .gitmodules file
 		if (generator.getModulesPath() == null)
 			return new SubmoduleStatus(SubmoduleStatusType.MISSING, path, id);
 
 		// Report uninitialized if no URL in config file
 		if (generator.getConfigUrl() == null)
 			return new SubmoduleStatus(SubmoduleStatusType.UNINITIALIZED, path,
 					id);
 
 		// Report uninitialized if no submodule repository
 		Repository subRepo = generator.getRepository();
 		if (subRepo == null)
 			return new SubmoduleStatus(SubmoduleStatusType.UNINITIALIZED, path,
 					id);
 
 		ObjectId headId;
 		try {
 			headId = subRepo.resolve(Constants.HEAD);
 		} finally {
 			subRepo.close();
 		}
 
 		// Report uninitialized if no HEAD commit in submodule repository
 		if (headId == null)
 			return new SubmoduleStatus(SubmoduleStatusType.UNINITIALIZED, path,
 					id, headId);
 
 		// Report checked out if HEAD commit is different than index commit
 		if (!headId.equals(id))
 			return new SubmoduleStatus(SubmoduleStatusType.REV_CHECKED_OUT,
 					path, id, headId);
 
 		// Report initialized if HEAD commit is the same as the index commit
 		return new SubmoduleStatus(SubmoduleStatusType.INITIALIZED, path, id,
 				headId);
 	}
 }