/*
 * Copyright (C) 2017, Matthias Sohn <matthias.sohn@sap.com>
 * 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,
 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
 * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */
package org.eclipse.jgit.pgm;

import static java.util.function.Predicate.isEqual;
import static org.eclipse.jgit.lib.FileMode.EXECUTABLE_FILE;
import static org.eclipse.jgit.lib.FileMode.GITLINK;
import static org.eclipse.jgit.lib.FileMode.REGULAR_FILE;
import static org.eclipse.jgit.lib.FileMode.SYMLINK;

import java.io.IOException;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.List;

import org.eclipse.jgit.dircache.DirCacheIterator;
import org.eclipse.jgit.errors.RevisionSyntaxException;
import org.eclipse.jgit.lib.Constants;
import org.eclipse.jgit.lib.FileMode;
import org.eclipse.jgit.lib.ObjectId;
import org.eclipse.jgit.revwalk.RevCommit;
import org.eclipse.jgit.revwalk.RevWalk;
import org.eclipse.jgit.treewalk.CanonicalTreeParser;
import org.eclipse.jgit.treewalk.TreeWalk;
import org.eclipse.jgit.treewalk.filter.PathFilterGroup;
import org.eclipse.jgit.util.QuotedString;
import org.kohsuke.args4j.Option;
import org.kohsuke.args4j.spi.StopOptionHandler;

@Command(common = true, usage = "usage_LsFiles")
class LsFiles extends TextBuiltin {

	@Option(name = "--", metaVar = "metaVar_paths", handler = StopOptionHandler.class)
	private List<String> paths = new ArrayList<>();

	@Override
	protected void run() {
		try (RevWalk rw = new RevWalk(db);
				TreeWalk tw = new TreeWalk(db)) {
			final ObjectId head = db.resolve(Constants.HEAD);
			if (head == null) {
				return;
			}
			RevCommit c = rw.parseCommit(head);
			CanonicalTreeParser p = new CanonicalTreeParser();
			p.reset(rw.getObjectReader(), c.getTree());
			tw.reset(); // drop the first empty tree, which we do not need here
			if (!paths.isEmpty()) {
				tw.setFilter(PathFilterGroup.createFromStrings(paths));
			}
			tw.addTree(p);
			tw.addTree(new DirCacheIterator(db.readDirCache()));
			tw.setRecursive(true);
			while (tw.next()) {
				if (filterFileMode(tw, EXECUTABLE_FILE, GITLINK, REGULAR_FILE,
						SYMLINK)) {
					outw.println(
							QuotedString.GIT_PATH.quote(tw.getPathString()));
				}
			}
		} catch (RevisionSyntaxException | IOException e) {
			throw die(e.getMessage(), e);
		}
	}

	private boolean filterFileMode(TreeWalk tw, FileMode... modes) {
		return Arrays.stream(modes).anyMatch(isEqual(tw.getFileMode(0))
				.or(isEqual(tw.getFileMode(1))));
	}
}