tikhomirov@107: /*
tikhomirov@107:  * Copyright (c) 2011 TMate Software Ltd
tikhomirov@107:  *  
tikhomirov@107:  * This program is free software; you can redistribute it and/or modify
tikhomirov@107:  * it under the terms of the GNU General Public License as published by
tikhomirov@107:  * the Free Software Foundation; version 2 of the License.
tikhomirov@107:  *
tikhomirov@107:  * This program is distributed in the hope that it will be useful,
tikhomirov@107:  * but WITHOUT ANY WARRANTY; without even the implied warranty of
tikhomirov@107:  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
tikhomirov@107:  * GNU General Public License for more details.
tikhomirov@107:  *
tikhomirov@107:  * For information on how to redistribute this software under
tikhomirov@107:  * the terms of a license other than GNU General Public License
tikhomirov@130:  * contact TMate Software at support@hg4j.com
tikhomirov@107:  */
tikhomirov@107: package org.tmatesoft.hg.core;
tikhomirov@107: 
tikhomirov@148: import static org.tmatesoft.hg.repo.HgInternals.wrongLocalRevision;
tikhomirov@107: import static org.tmatesoft.hg.repo.HgRepository.BAD_REVISION;
tikhomirov@107: import static org.tmatesoft.hg.repo.HgRepository.TIP;
tikhomirov@107: 
tikhomirov@107: import java.io.FileNotFoundException;
tikhomirov@322: import java.io.IOException;
tikhomirov@322: import java.nio.ByteBuffer;
tikhomirov@107: 
tikhomirov@107: import org.tmatesoft.hg.repo.HgDataFile;
tikhomirov@107: import org.tmatesoft.hg.repo.HgRepository;
tikhomirov@322: import org.tmatesoft.hg.util.Adaptable;
tikhomirov@115: import org.tmatesoft.hg.util.ByteChannel;
tikhomirov@322: import org.tmatesoft.hg.util.CancelSupport;
tikhomirov@148: import org.tmatesoft.hg.util.CancelledException;
tikhomirov@133: import org.tmatesoft.hg.util.Path;
tikhomirov@107: 
tikhomirov@107: /**
tikhomirov@131:  * Command to obtain content of a file, 'hg cat' counterpart. 
tikhomirov@107:  * 
tikhomirov@107:  * @author Artem Tikhomirov
tikhomirov@107:  * @author TMate Software Ltd.
tikhomirov@107:  */
tikhomirov@215: public class HgCatCommand extends HgAbstractCommand<HgCatCommand> {
tikhomirov@107: 
tikhomirov@107: 	private final HgRepository repo;
tikhomirov@107: 	private Path file;
tikhomirov@107: 	private int localRevision = TIP;
tikhomirov@107: 	private Nodeid revision;
tikhomirov@232: 	private Nodeid cset;
tikhomirov@107: 
tikhomirov@131: 	public HgCatCommand(HgRepository hgRepo) {
tikhomirov@107: 		repo = hgRepo;
tikhomirov@107: 	}
tikhomirov@107: 
tikhomirov@148: 	/**
tikhomirov@148: 	 * File to read, required parameter 
tikhomirov@148: 	 * @param fname path to a repository file, can't be <code>null</code>
tikhomirov@148: 	 * @return <code>this</code> for convenience
tikhomirov@148: 	 * @throws IllegalArgumentException if supplied fname is null or points to directory
tikhomirov@148: 	 */
tikhomirov@131: 	public HgCatCommand file(Path fname) {
tikhomirov@148: 		if (fname == null || fname.isDirectory()) {
tikhomirov@148: 			throw new IllegalArgumentException(String.valueOf(fname));
tikhomirov@148: 		}
tikhomirov@107: 		file = fname;
tikhomirov@107: 		return this;
tikhomirov@107: 	}
tikhomirov@107: 
tikhomirov@148: 	/**
tikhomirov@232: 	 * Select specific local revision of the file to cat. Note, revision numbering is of particular file, not that of
tikhomirov@232: 	 * repository (i.e. revision 0 means initial content of the file, irrespective of changeset revision at the time of commit) 
tikhomirov@232: 	 * 
tikhomirov@148: 	 * Invocation of this method clears revision set with {@link #revision(Nodeid)} or {@link #revision(int)} earlier.
tikhomirov@232: 	 * 
tikhomirov@148: 	 * XXX rev can't be WORKING_COPY (if allowed, need to implement in #execute())
tikhomirov@148: 	 * @param rev local revision number, non-negative, or one of predefined constants. Note, use of {@link HgRepository#BAD_REVISION}, 
tikhomirov@148: 	 * although possible, makes little sense (command would fail if executed).  
tikhomirov@148:  	 * @return <code>this</code> for convenience
tikhomirov@148: 	 */
tikhomirov@131: 	public HgCatCommand revision(int rev) {
tikhomirov@148: 		if (wrongLocalRevision(rev)) {
tikhomirov@148: 			throw new IllegalArgumentException(String.valueOf(rev));
tikhomirov@148: 		}
tikhomirov@107: 		localRevision = rev;
tikhomirov@107: 		revision = null;
tikhomirov@232: 		cset = null;
tikhomirov@107: 		return this;
tikhomirov@107: 	}
tikhomirov@107: 	
tikhomirov@148: 	/**
tikhomirov@232: 	 * Select revision to read. Note, this revision is file revision (i.e. the one from manifest), not the changeset revision.
tikhomirov@232: 	 *  
tikhomirov@232: 	 * Invocation of this method clears revision set with {@link #revision(int)} or {@link #revision(Nodeid)} earlier.
tikhomirov@148: 	 * 
tikhomirov@232: 	 * @param nodeid - unique file revision identifier, Note, use of <code>null</code> or {@link Nodeid#NULL} is senseless
tikhomirov@148: 	 * @return <code>this</code> for convenience
tikhomirov@148: 	 */
tikhomirov@131: 	public HgCatCommand revision(Nodeid nodeid) {
tikhomirov@148: 		if (nodeid != null && nodeid.isNull()) {
tikhomirov@148: 			nodeid = null;
tikhomirov@148: 		}
tikhomirov@107: 		revision = nodeid;
tikhomirov@107: 		localRevision = BAD_REVISION;
tikhomirov@232: 		cset = null;
tikhomirov@232: 		return this;
tikhomirov@232: 	}
tikhomirov@248: 
tikhomirov@248: 	/**
tikhomirov@248: 	 * Parameterize the command from file revision object.
tikhomirov@248: 	 * 
tikhomirov@248: 	 * @param fileRev file revision to cat 
tikhomirov@248: 	 * @return <code>this</code> for convenience
tikhomirov@248: 	 */
tikhomirov@248: 	public HgCatCommand revision(HgFileRevision fileRev) {
tikhomirov@248: 		return file(fileRev.getPath()).revision(fileRev.getRevision());
tikhomirov@248: 	}
tikhomirov@232: 	
tikhomirov@232: 	/**
tikhomirov@232: 	 * Select whatever revision of the file that was actual at the time of the specified changeset. Unlike {@link #revision(int)} or {@link #revision(Nodeid)}, this method 
tikhomirov@232: 	 * operates in terms of repository global revisions (aka changesets). 
tikhomirov@232: 	 * 
tikhomirov@232: 	 * Invocation of this method clears local file revisions selection.
tikhomirov@232: 	 * 
tikhomirov@232: 	 * @param nodeid changeset revision
tikhomirov@232: 	 * @return <code>this</code> for convenience
tikhomirov@232: 	 */
tikhomirov@232: 	public HgCatCommand changeset(Nodeid nodeid) {
tikhomirov@232: 		localRevision = BAD_REVISION;
tikhomirov@232: 		revision = null;
tikhomirov@232: 		cset = nodeid;
tikhomirov@107: 		return this;
tikhomirov@107: 	}
tikhomirov@107: 
tikhomirov@148: 	/**
tikhomirov@148: 	 * Runs the command with current set of parameters and pipes data to provided sink.
tikhomirov@148: 	 * 
tikhomirov@148: 	 * @param sink output channel to write data to.
tikhomirov@148: 	 * @throws HgDataStreamException 
tikhomirov@148: 	 * @throws IllegalArgumentException when command arguments are incomplete or wrong
tikhomirov@148: 	 */
tikhomirov@354: 	public void execute(ByteChannel sink) throws HgDataStreamException, HgInvalidControlFileException, CancelledException {
tikhomirov@232: 		if (localRevision == BAD_REVISION && revision == null && cset == null) {
tikhomirov@232: 			throw new IllegalArgumentException("File revision, corresponing local number, or a changset nodeid shall be specified");
tikhomirov@107: 		}
tikhomirov@107: 		if (file == null) {
tikhomirov@107: 			throw new IllegalArgumentException("Name of the file is missing");
tikhomirov@107: 		}
tikhomirov@115: 		if (sink == null) {
tikhomirov@148: 			throw new IllegalArgumentException("Need an output channel");
tikhomirov@107: 		}
tikhomirov@107: 		HgDataFile dataFile = repo.getFileNode(file);
tikhomirov@107: 		if (!dataFile.exists()) {
tikhomirov@215: 			throw new HgDataStreamException(file, new FileNotFoundException(file.toString()));
tikhomirov@107: 		}
tikhomirov@115: 		int revToExtract;
tikhomirov@232: 		if (cset != null) {
tikhomirov@232: 			int csetRev = repo.getChangelog().getLocalRevision(cset);
tikhomirov@232: 			Nodeid toExtract = null;
tikhomirov@232: 			do {
tikhomirov@232: 				toExtract = repo.getManifest().getFileRevision(csetRev, file);
tikhomirov@232: 				if (toExtract == null) {
tikhomirov@232: 					if (dataFile.isCopy()) {
tikhomirov@232: 						file = dataFile.getCopySourceName();
tikhomirov@232: 						dataFile = repo.getFileNode(file);
tikhomirov@232: 					} else {
tikhomirov@232: 						break;
tikhomirov@232: 					}
tikhomirov@232: 				}
tikhomirov@232: 			} while (toExtract == null);
tikhomirov@232: 			if (toExtract == null) {
tikhomirov@248: 				throw new HgBadStateException(String.format("File %s nor its origins were not known at repository %s revision", file, cset.shortNotation()));
tikhomirov@232: 			}
tikhomirov@232: 			revToExtract = dataFile.getLocalRevision(toExtract);
tikhomirov@232: 		} else if (revision != null) {
tikhomirov@115: 			revToExtract = dataFile.getLocalRevision(revision);
tikhomirov@107: 		} else {
tikhomirov@115: 			revToExtract = localRevision;
tikhomirov@107: 		}
tikhomirov@322: 		ByteChannel sinkWrap;
tikhomirov@322: 		if (getCancelSupport(null, false) == null) {
tikhomirov@322: 			// no command-specific cancel helper, no need for extra proxy
tikhomirov@322: 			// sink itself still may supply CS
tikhomirov@322: 			sinkWrap = sink;
tikhomirov@322: 		} else {
tikhomirov@322: 			// try CS from sink, if any. at least there is CS from command 
tikhomirov@322: 			CancelSupport cancelHelper = getCancelSupport(sink, true);
tikhomirov@322: 			cancelHelper.checkCancelled();
tikhomirov@322: 			sinkWrap = new ByteChannelProxy(sink, cancelHelper);
tikhomirov@322: 		}
tikhomirov@322: 		dataFile.contentWithFilters(revToExtract, sinkWrap);
tikhomirov@322: 	}
tikhomirov@322: 
tikhomirov@322: 	private static class ByteChannelProxy implements ByteChannel, Adaptable {
tikhomirov@322: 		private final ByteChannel delegate;
tikhomirov@322: 		private final CancelSupport cancelHelper;
tikhomirov@322: 
tikhomirov@322: 		public ByteChannelProxy(ByteChannel _delegate, CancelSupport cs) {
tikhomirov@322: 			assert _delegate != null;
tikhomirov@322: 			delegate = _delegate;
tikhomirov@322: 			cancelHelper = cs;
tikhomirov@322: 		}
tikhomirov@322: 		public int write(ByteBuffer buffer) throws IOException, CancelledException {
tikhomirov@322: 			return delegate.write(buffer);
tikhomirov@322: 		}
tikhomirov@322: 
tikhomirov@322: 		public <T> T getAdapter(Class<T> adapterClass) {
tikhomirov@322: 			if (CancelSupport.class == adapterClass) {
tikhomirov@322: 				return adapterClass.cast(cancelHelper);
tikhomirov@322: 			}
tikhomirov@322: 			if (delegate instanceof Adaptable) {
tikhomirov@322: 				return ((Adaptable) delegate).getAdapter(adapterClass);
tikhomirov@322: 			}
tikhomirov@322: 			if (adapterClass.isInstance(delegate)) {
tikhomirov@322: 				return adapterClass.cast(delegate);
tikhomirov@322: 			}
tikhomirov@322: 			return null;
tikhomirov@322: 		}
tikhomirov@107: 	}
tikhomirov@107: }