/*
    * Copyright (C) 2017, Matthias Sohn <matthias.sohn@sap.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.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 (RevWalkRevWalk.html#RevWalk">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))));
  	}
  }