/*
 * Copyright (c) 2010-2011 TMate Software Ltd
 *  
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; version 2 of the License.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * For information on how to redistribute this software under
 * the terms of a license other than GNU General Public License
 * contact TMate Software at support@hg4j.com
 */
package org.tmatesoft.hg.repo;

import java.io.IOException;

import org.tmatesoft.hg.core.HgBadStateException;
import org.tmatesoft.hg.core.Nodeid;
import org.tmatesoft.hg.internal.DataAccess;
import org.tmatesoft.hg.internal.RevlogStream;


/**
 *
 * @author Artem Tikhomirov
 * @author TMate Software Ltd.
 */
public class HgManifest extends Revlog {

	/*package-local*/ HgManifest(HgRepository hgRepo, RevlogStream content) {
		super(hgRepo, content);
	}

	public void walk(int start, int end, final Inspector inspector) {
		RevlogStream.Inspector insp = new RevlogStream.Inspector() {

			private boolean gtg = true; // good to go

			public void next(int revisionNumber, int actualLen, int baseRevision, int linkRevision, int parent1Revision, int parent2Revision, byte[] nodeid, DataAccess da) {
				if (!gtg) {
					return;
				}
				try {
					gtg = gtg && inspector.begin(revisionNumber, new Nodeid(nodeid, true));
					int i;
					String fname = null;
					String flags = null;
					Nodeid nid = null;
					byte[] data = da.byteArray();
					for (i = 0; gtg && i < actualLen; i++) {
						int x = i;
						for( ; data[i] != '\n' && i < actualLen; i++) {
							if (fname == null && data[i] == 0) {
								fname = new String(data, x, i - x);
								x = i+1;
							}
						}
						if (i < actualLen) {
							assert data[i] == '\n'; 
							int nodeidLen = i - x < 40 ? i-x : 40;
							nid = Nodeid.fromAscii(data, x, nodeidLen);
							if (nodeidLen + x < i) {
								// 'x' and 'l' for executable bits and symlinks?
								// hg --debug manifest shows 644 for each regular file in my repo
								flags = new String(data, x + nodeidLen, i-x-nodeidLen);
							}
							gtg = gtg && inspector.next(nid, fname, flags);
						}
						nid = null;
						fname = flags = null;
					}
					gtg = gtg && inspector.end(revisionNumber);
				} catch (IOException ex) {
					throw new HgBadStateException(ex);
				}
			}
		};
		content.iterate(start, end, true, insp);
	}

	public interface Inspector {
		boolean begin(int revision, Nodeid nid);
		boolean next(Nodeid nid, String fname, String flags);
		boolean end(int revision);
	}
}