tikhomirov@248: /*
tikhomirov@690:  * Copyright (c) 2011-2013 TMate Software Ltd
tikhomirov@248:  *  
tikhomirov@248:  * This program is free software; you can redistribute it and/or modify
tikhomirov@248:  * it under the terms of the GNU General Public License as published by
tikhomirov@248:  * the Free Software Foundation; version 2 of the License.
tikhomirov@248:  *
tikhomirov@248:  * This program is distributed in the hope that it will be useful,
tikhomirov@248:  * but WITHOUT ANY WARRANTY; without even the implied warranty of
tikhomirov@248:  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
tikhomirov@248:  * GNU General Public License for more details.
tikhomirov@248:  *
tikhomirov@248:  * For information on how to redistribute this software under
tikhomirov@248:  * the terms of a license other than GNU General Public License
tikhomirov@248:  * contact TMate Software at support@hg4j.com
tikhomirov@248:  */
tikhomirov@248: package org.tmatesoft.hg.core;
tikhomirov@248: 
tikhomirov@690: import java.util.ArrayDeque;
tikhomirov@690: 
tikhomirov@248: import org.tmatesoft.hg.internal.ManifestRevision;
tikhomirov@248: import org.tmatesoft.hg.repo.HgDataFile;
tikhomirov@423: import org.tmatesoft.hg.repo.HgInvalidStateException;
tikhomirov@415: import org.tmatesoft.hg.repo.HgManifest;
tikhomirov@690: import org.tmatesoft.hg.repo.HgManifest.Flags;
tikhomirov@248: import org.tmatesoft.hg.repo.HgRepository;
tikhomirov@423: import org.tmatesoft.hg.repo.HgRuntimeException;
tikhomirov@690: import org.tmatesoft.hg.util.Outcome;
tikhomirov@690: import org.tmatesoft.hg.util.Pair;
tikhomirov@248: import org.tmatesoft.hg.util.Path;
tikhomirov@248: 
tikhomirov@248: /**
tikhomirov@248:  * Primary purpose is to provide information about file revisions at specific changeset. Multiple {@link #check(Path)} calls 
tikhomirov@248:  * are possible once {@link #changeset(Nodeid)} (and optionally, {@link #followRenames(boolean)}) were set.
tikhomirov@251:  * 
tikhomirov@251:  * <p>Sample:
tikhomirov@251:  * <pre><code>
tikhomirov@417:  *   HgChangesetFileSneaker i = new HgChangesetFileSneaker(hgRepo).changeset(Nodeid.fromString("<40 digits>")).followRenames(true);
tikhomirov@251:  *   if (i.check(file)) {
tikhomirov@251:  *   	HgCatCommand catCmd = new HgCatCommand(hgRepo).revision(i.getFileRevision());
tikhomirov@251:  *   	catCmd.execute(...);
tikhomirov@251:  *   	...
tikhomirov@251:  *   }
tikhomirov@251:  * </pre></code>
tikhomirov@248:  *
tikhomirov@417:  * TODO may add #manifest(Nodeid) to select manifest according to its revision (not only changeset revision as it's now)
tikhomirov@354:  * 
tikhomirov@417:  * <p>Unlike {@link HgManifest#getFileRevision(int, Path)}, this class is useful when few files from the same changeset have to be inspected
tikhomirov@417:  * 
tikhomirov@417:  * @see HgManifest#getFileRevision(int, Path)
tikhomirov@248:  * @author Artem Tikhomirov
tikhomirov@248:  * @author TMate Software Ltd.
tikhomirov@248:  */
tikhomirov@434: public final class HgChangesetFileSneaker {
tikhomirov@248: 
tikhomirov@248: 	private final HgRepository repo;
tikhomirov@248: 	private boolean followRenames;
tikhomirov@248: 	private Nodeid cset;
tikhomirov@248: 	private ManifestRevision cachedManifest;
tikhomirov@248: 	private HgFileRevision fileRevision;
tikhomirov@361: 	private boolean renamed;
tikhomirov@454: 	private Outcome checkResult;
tikhomirov@248: 
tikhomirov@417: 	public HgChangesetFileSneaker(HgRepository hgRepo) {
tikhomirov@248: 		repo = hgRepo;
tikhomirov@248: 	}
tikhomirov@248: 
tikhomirov@251: 	/**
tikhomirov@251: 	 * Select specific changelog revision
tikhomirov@251: 	 * 
tikhomirov@251: 	 * @param nid changeset identifier
tikhomirov@251: 	 * @return <code>this</code> for convenience
tikhomirov@251: 	 */
tikhomirov@417: 	public HgChangesetFileSneaker changeset(Nodeid nid) {
tikhomirov@274: 		if (nid == null || nid.isNull()) {
tikhomirov@248: 			throw new IllegalArgumentException(); 
tikhomirov@248: 		}
tikhomirov@248: 		cset = nid;
tikhomirov@248: 		cachedManifest = null;
tikhomirov@248: 		fileRevision = null;
tikhomirov@248: 		return this;
tikhomirov@248: 	}
tikhomirov@251: 
tikhomirov@251: 	/**
tikhomirov@251: 	 * Whether to check file origins, default is false (look up only the name supplied)
tikhomirov@251: 	 *
tikhomirov@251: 	 * @param follow <code>true</code> to check copy/rename origin of the file if it is a copy.
tikhomirov@251: 	 * @return <code>this</code> for convenience
tikhomirov@251: 	 */
tikhomirov@417: 	public HgChangesetFileSneaker followRenames(boolean follow) {
tikhomirov@248: 		followRenames = follow;
tikhomirov@248: 		fileRevision = null;
tikhomirov@248: 		return this;
tikhomirov@248: 	}
tikhomirov@248: 
tikhomirov@251: 	/**
tikhomirov@454: 	 * Shortcut to perform {@link #check(Path)} and {@link #exists()}. Result of the check may be accessed via {@link #getCheckResult()}.
tikhomirov@427: 	 * Errors during the check, if any, are reported through exception.
tikhomirov@251: 	 * 
tikhomirov@251: 	 * @param file name of the file in question
tikhomirov@251: 	 * @return <code>true</code> if file is known at the selected changeset.
tikhomirov@427: 	 * @throws HgException subclass thereof to indicate specific issue with the command arguments or repository state
tikhomirov@251: 	 * @throws IllegalArgumentException if {@link #changeset(Nodeid)} not specified or file argument is bad.
tikhomirov@251: 	 */
tikhomirov@427: 	public boolean checkExists(Path file) throws HgException {
tikhomirov@361: 		check(file);
tikhomirov@427: 		// next seems reasonable, however renders boolean return value useless. perhaps void or distinct method?
tikhomirov@427: //		if (checkResult.isOk() && !exists()) {
tikhomirov@427: //			throw new HgPathNotFoundException(checkResult.getMessage(), file);
tikhomirov@427: //		}
tikhomirov@427: 		if (!checkResult.isOk() && checkResult.getException() instanceof HgRuntimeException) {
tikhomirov@427: 			throw new HgLibraryFailureException((HgRuntimeException) checkResult.getException());
tikhomirov@361: 		}
tikhomirov@361: 		return checkResult.isOk() && exists();
tikhomirov@361: 	}
tikhomirov@361: 
tikhomirov@361: 	/**
tikhomirov@361: 	 * Find file (or its origin, if {@link #followRenames(boolean)} was set to <code>true</code>) among files known at specified {@link #changeset(Nodeid)}.
tikhomirov@361: 	 * 
tikhomirov@361: 	 * @param file name of the file in question
tikhomirov@454: 	 * @return status object that describes outcome, {@link Outcome#isOk() Ok} status indicates successful completion of the operation, but doesn't imply
tikhomirov@361: 	 * file existence, use {@link #exists()} for that purpose. Message of the status may provide further hints on what exactly had happened. 
tikhomirov@361: 	 * @throws IllegalArgumentException if {@link #changeset(Nodeid)} not specified or file argument is bad.
tikhomirov@361: 	 */
tikhomirov@454: 	public Outcome check(Path file) {
tikhomirov@248: 		fileRevision = null;
tikhomirov@361: 		checkResult = null;
tikhomirov@248: 		renamed = false;
tikhomirov@248: 		if (cset == null || file == null || file.isDirectory()) {
tikhomirov@248: 			throw new IllegalArgumentException();
tikhomirov@248: 		}
tikhomirov@248: 		HgDataFile dataFile = repo.getFileNode(file);
tikhomirov@248: 		if (!dataFile.exists()) {
tikhomirov@454: 			checkResult = new Outcome(Outcome.Kind.Success, String.format("File named %s is not known in the repository", file));
tikhomirov@361: 			return checkResult;
tikhomirov@248: 		}
tikhomirov@361: 		Nodeid toExtract = null;
tikhomirov@396: 		String phaseMsg = "Extract manifest revision failed";
tikhomirov@248: 		try {
tikhomirov@361: 			if (cachedManifest == null) {
tikhomirov@367: 				int csetRev = repo.getChangelog().getRevisionIndex(cset);
tikhomirov@361: 				cachedManifest = new ManifestRevision(null, null); // XXX how about context and cached manifest revisions
tikhomirov@361: 				repo.getManifest().walk(csetRev, csetRev, cachedManifest);
tikhomirov@367: 				// cachedManifest shall be meaningful - changelog.getRevisionIndex() above ensures we've got version that exists.
tikhomirov@361: 			}
tikhomirov@361: 			toExtract = cachedManifest.nodeid(file);
tikhomirov@396: 			phaseMsg = "Follow copy/rename failed";
tikhomirov@248: 			if (toExtract == null && followRenames) {
tikhomirov@690: 				int csetIndex = repo.getChangelog().getRevisionIndex(cset);
tikhomirov@690: 				int ccFileRevIndex = dataFile.getLastRevision(); // copy candidate
tikhomirov@690: 				int csetFileEnds = dataFile.getChangesetRevisionIndex(ccFileRevIndex);
tikhomirov@690: 				if (csetIndex > csetFileEnds) {
tikhomirov@690: 					return new Outcome(Outcome.Kind.Success, String.format("%s: last known changeset for the file %s is %d. Follow renames is possible towards older changesets only", phaseMsg, file, csetFileEnds));
tikhomirov@248: 				}
tikhomirov@691: 				// @see FileRenameHistory, with similar code, which doesn't trace alternative paths
tikhomirov@690: 				// traceback stack keeps record of all files with isCopy(fileRev) == true we've tried to follow, so that we can try earlier file
tikhomirov@690: 				// revisions in case followed fileRev didn't succeed
tikhomirov@690: 				ArrayDeque<Pair<HgDataFile, Integer>> traceback = new ArrayDeque<Pair<HgDataFile, Integer>>();
tikhomirov@690: 				do {
tikhomirov@690: 					int ccCsetIndex = dataFile.getChangesetRevisionIndex(ccFileRevIndex);
tikhomirov@690: 					if (ccCsetIndex <= csetIndex) {
tikhomirov@690: 						// present dataFile is our (distant) origin
tikhomirov@690: 						toExtract = dataFile.getRevision(ccFileRevIndex);
tikhomirov@690: 						renamed = true;
tikhomirov@690: 						break;
tikhomirov@690: 					}
tikhomirov@690: 					if (!dataFile.isCopy(ccFileRevIndex)) {
tikhomirov@690: 						// nothing left to return to when traceback.isEmpty()
tikhomirov@690: 						while (ccFileRevIndex == 0 && !traceback.isEmpty()) {
tikhomirov@690: 							Pair<HgDataFile, Integer> lastTurnPoint = traceback.pop();
tikhomirov@690: 							dataFile = lastTurnPoint.first();
tikhomirov@690: 							ccFileRevIndex = lastTurnPoint.second(); // generally ccFileRevIndex != 0 here, but doesn't hurt to check, hence while
tikhomirov@690: 							// fall through to shift down from the file revision we've already looked at
tikhomirov@690: 						}
tikhomirov@690: 						ccFileRevIndex--;
tikhomirov@690: 						continue;
tikhomirov@690: 					}
tikhomirov@690: 					if (ccFileRevIndex > 0) {
tikhomirov@690: 						// there's no reason to memorize turn point if it's the very first revision
tikhomirov@690: 						// of the file and we won't be able to try any other earlier revision
tikhomirov@690: 						traceback.push(new Pair<HgDataFile, Integer>(dataFile, ccFileRevIndex));
tikhomirov@690: 					}
tikhomirov@690: 					HgFileRevision origin = dataFile.getCopySource(ccFileRevIndex);
tikhomirov@690: 					dataFile = repo.getFileNode(origin.getPath());
tikhomirov@690: 					ccFileRevIndex = dataFile.getRevisionIndex(origin.getRevision());
tikhomirov@690: 				} while (ccFileRevIndex >= 0);
tikhomirov@690: 				// didn't get to csetIndex, no ancestor in file rename history found.
tikhomirov@248: 			}
tikhomirov@423: 		} catch (HgRuntimeException ex) {
tikhomirov@454: 			checkResult = new Outcome(Outcome.Kind.Failure, phaseMsg, ex);
tikhomirov@361: 			return checkResult;
tikhomirov@248: 		}
tikhomirov@248: 		if (toExtract != null) {
tikhomirov@690: 			Flags extractRevFlags = cachedManifest.flags(dataFile.getPath());
tikhomirov@415: 			fileRevision = new HgFileRevision(repo, toExtract, extractRevFlags, dataFile.getPath());
tikhomirov@454: 			checkResult = new Outcome(Outcome.Kind.Success, String.format("File %s, revision %s found at changeset %s", dataFile.getPath(), toExtract.shortNotation(), cset.shortNotation()));
tikhomirov@361: 			return checkResult;
tikhomirov@361: 		} 
tikhomirov@690: 		checkResult = new Outcome(Outcome.Kind.Success, String.format("File %s nor its origins were known at revision %s", file, cset.shortNotation()));
tikhomirov@361: 		return checkResult;
tikhomirov@361: 	}
tikhomirov@361: 	
tikhomirov@361: 	/**
tikhomirov@361: 	 * Re-get latest check status object
tikhomirov@361: 	 */
tikhomirov@454: 	public Outcome getCheckResult() {
tikhomirov@361: 		assertCheckRan();
tikhomirov@361: 		return checkResult;
tikhomirov@248: 	}
tikhomirov@248: 	
tikhomirov@248: 	/**
tikhomirov@248: 	 * @return result of the last {@link #check(Path)} call.
tikhomirov@248: 	 */
tikhomirov@248: 	public boolean exists() {
tikhomirov@248: 		assertCheckRan();
tikhomirov@248: 		return fileRevision != null;
tikhomirov@248: 	}
tikhomirov@248: 	
tikhomirov@248: 	/**
tikhomirov@248: 	 * @return <code>true</code> if checked file was known by another name at the time of specified changeset.
tikhomirov@248: 	 */
tikhomirov@248: 	public boolean hasAnotherName() {
tikhomirov@248: 		assertCheckRan();
tikhomirov@248: 		return renamed;
tikhomirov@248: 	}
tikhomirov@248: 
tikhomirov@248: 	/**
tikhomirov@248: 	 * @return holder for file revision information
tikhomirov@248: 	 */
tikhomirov@248: 	public HgFileRevision getFileRevision() {
tikhomirov@248: 		assertCheckRan();
tikhomirov@248: 		return fileRevision;
tikhomirov@248: 	}
tikhomirov@248: 
tikhomirov@248: 	/**
tikhomirov@248: 	 * Name of the checked file as it was known at the time of the specified changeset.
tikhomirov@248: 	 * 
tikhomirov@248: 	 * @return handy shortcut for <code>getFileRevision().getPath()</code>
tikhomirov@248: 	 */
tikhomirov@248: 	public Path filename() {
tikhomirov@248: 		assertCheckRan();
tikhomirov@248: 		return fileRevision.getPath();
tikhomirov@248: 	}
tikhomirov@248: 	
tikhomirov@248: 	/**
tikhomirov@248: 	 * Revision of the checked file
tikhomirov@248: 	 * 
tikhomirov@248: 	 * @return handy shortcut for <code>getFileRevision().getRevision()</code>
tikhomirov@248: 	 */
tikhomirov@248: 	public Nodeid revision() {
tikhomirov@248: 		assertCheckRan();
tikhomirov@248: 		return fileRevision.getRevision();
tikhomirov@248: 	}
tikhomirov@248: 
tikhomirov@248: 	private void assertCheckRan() {
tikhomirov@361: 		if (checkResult == null) {
tikhomirov@423: 			throw new HgInvalidStateException("Shall invoke #check(Path) first");
tikhomirov@248: 		}
tikhomirov@248: 	}
tikhomirov@417: 
tikhomirov@248: }