/*
    * Copyright (C) 2008-2009, Google Inc.
    * Copyright (C) 2008, Shawn O. Pearce <spearce@spearce.org>
    * 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
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   * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
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  package org.eclipse.jgit.pgm.opt;
  
  import java.io.File;
  import java.io.IOException;
  import java.text.MessageFormat;
  
  import org.kohsuke.args4j.CmdLineException;
  import org.kohsuke.args4j.CmdLineParser;
  import org.kohsuke.args4j.OptionDef;
  import org.kohsuke.args4j.spi.OptionHandler;
  import org.kohsuke.args4j.spi.Parameters;
  import org.kohsuke.args4j.spi.Setter;
  import org.eclipse.jgit.dircache.DirCache;
  import org.eclipse.jgit.dircache.DirCacheIterator;
  import org.eclipse.jgit.errors.IncorrectObjectTypeException;
  import org.eclipse.jgit.errors.MissingObjectException;
  import org.eclipse.jgit.lib.ObjectId;
  import org.eclipse.jgit.lib.ObjectReader;
  import org.eclipse.jgit.pgm.internal.CLIText;
  import org.eclipse.jgit.treewalk.AbstractTreeIterator;
  import org.eclipse.jgit.treewalk.CanonicalTreeParser;
  import org.eclipse.jgit.treewalk.FileTreeIterator;
  import org.eclipse.jgit.treewalk.WorkingTreeOptions;
  import org.eclipse.jgit.util.FS;
  
  /**
   * Custom argument handler {@link AbstractTreeIterator} from string values.
   * <p>
   * Assumes the parser has been initialized with a Repository.
   */
  public class AbstractTreeIteratorHandler extends
  		OptionHandler<AbstractTreeIterator> {
  	private final org.eclipse.jgit.pgm.opt.CmdLineParser clp;
  
  	/**
  	 * Create a new handler for the command name.
  	 * <p>
  	 * This constructor is used only by args4j.
  	 *
  	 * @param parser
  	 * @param option
  	 * @param setter
  	 */
  	public AbstractTreeIteratorHandler(final CmdLineParser parser,
  			final OptionDef option,
  			final Setter<? super AbstractTreeIterator> setter) {
  		super(parser, option, setter);
  		clp = (org.eclipse.jgit.pgm.opt.CmdLineParser) parser;
  	}
  
  	@Override
  	public int parseArguments(final Parameters params) throws CmdLineException {
  		final String name = params.getParameter(0);
  
  		if (new File(name).isDirectory()) {
 			setter.addValue(new FileTreeIterator(
 				new File(name),
 				FS.DETECTED,
 				clp.getRepository().getConfig().get(WorkingTreeOptions.KEY)));
 			return 1;
 		}
 
 		if (new File(name).isFile()) {
 			final DirCache dirc;
 			try {
 				dirc = DirCache.read(new File(name), FS.DETECTED);
 			} catch (IOException e) {
 				throw new CmdLineException(clp, MessageFormat.format(CLIText.get().notAnIndexFile, name), e);
 			}
 			setter.addValue(new DirCacheIterator(dirc));
 			return 1;
 		}
 
 		final ObjectId id;
 		try {
 			id = clp.getRepository().resolve(name);
 		} catch (IOException e) {
 			throw new CmdLineException(clp, e.getMessage());
 		}
 		if (id == null)
 			throw new CmdLineException(clp, MessageFormat.format(CLIText.get().notATree, name));
 
 		final CanonicalTreeParser p = new CanonicalTreeParser();
 		try (ObjectReader curs = clp.getRepository().newObjectReader()) {
 			p.reset(curs, clp.getRevWalk().parseTree(id));
 		} catch (MissingObjectException e) {
 			throw new CmdLineException(clp, MessageFormat.format(CLIText.get().notATree, name));
 		} catch (IncorrectObjectTypeException e) {
 			throw new CmdLineException(clp, MessageFormat.format(CLIText.get().notATree, name));
 		} catch (IOException e) {
 			throw new CmdLineException(clp, MessageFormat.format(CLIText.get().cannotReadBecause, name, e.getMessage()));
 		}
 
 		setter.addValue(p);
 		return 1;
 	}
 
 	@Override
 	public String getDefaultMetaVariable() {
 		return CLIText.get().metaVar_treeish;
 	}
 }