--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/org/tmatesoft/hg/internal/AnnotateFacility.java	Thu Feb 14 16:36:13 2013 +0100
@@ -0,0 +1,196 @@
+/*
+ * Copyright (c) 2013 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.internal;
+
+import static org.tmatesoft.hg.repo.HgRepository.NO_REVISION;
+
+import org.tmatesoft.hg.core.Nodeid;
+import org.tmatesoft.hg.internal.PatchGenerator.ChunkSequence;
+import org.tmatesoft.hg.repo.HgDataFile;
+import org.tmatesoft.hg.repo.HgInvalidStateException;
+import org.tmatesoft.hg.repo.HgRepository;
+import org.tmatesoft.hg.util.CancelledException;
+
+/**
+ * 
+ * @author Artem Tikhomirov
+ * @author TMate Software Ltd.
+ */
+@Experimental(reason="work in progress")
+public class AnnotateFacility {
+	
+	public void annotate(HgDataFile df, int changestRevisionIndex, Inspector insp) {
+		Nodeid fileRev = df.getRepo().getManifest().getFileRevision(changestRevisionIndex, df.getPath());
+		int fileRevIndex = df.getRevisionIndex(fileRev);
+		int[] fileRevParents = new int[2];
+		df.parents(fileRevIndex, fileRevParents, null, null);
+		if (fileRevParents[0] != NO_REVISION && fileRevParents[1] != NO_REVISION) {
+			// merge
+		} else if (fileRevParents[0] == fileRevParents[1]) {
+			// may be equal iff both are unset
+			assert fileRevParents[0] == NO_REVISION;
+			// everything added
+			insp.added(null);
+		} else {
+			int soleParent = fileRevParents[0] == NO_REVISION ? fileRevParents[1] : fileRevParents[0];
+			assert soleParent != NO_REVISION;
+			try {
+				ByteArrayChannel c1, c2;
+				df.content(soleParent, c1 = new ByteArrayChannel());
+				df.content(fileRevIndex, c2 = new ByteArrayChannel());
+				int parentChangesetRevIndex = df.getChangesetRevisionIndex(soleParent);
+				PatchGenerator pg = new PatchGenerator();
+				pg.init(c1.toArray(), c2.toArray());
+				pg.findMatchingBlocks(new BlameBlockInspector(insp));
+			} catch (CancelledException ex) {
+				// TODO likely it was bad idea to throw cancelled exception from content()
+				// deprecate and provide alternative?
+				HgInvalidStateException ise = new HgInvalidStateException("ByteArrayChannel never throws CancelledException");
+				ise.initCause(ex);
+				throw ise;
+			}
+		}
+	}
+
+	@Callback
+	public interface Inspector {
+		void same(Block block);
+		void added(AddBlock block);
+		void changed(ChangeBlock block);
+		void deleted(DeleteBlock block);
+	}
+	
+	public interface Block {
+//		boolean isMergeRevision();
+//		int fileRevisionIndex();
+//		int originFileRevisionIndex();
+//		String[] lines();
+//		byte[] data();
+	}
+	
+	public interface AddBlock extends Block {
+		int firstAddedLine();
+		int totalAddedLines();
+		String[] addedLines();
+	}
+	public interface DeleteBlock extends Block {
+		int firstRemovedLine();
+		int totalRemovedLines();
+		String[] removedLines();
+	}
+	public interface ChangeBlock extends AddBlock, DeleteBlock {
+	}
+
+	static class BlameBlockInspector extends PatchGenerator.DeltaInspector {
+		private final Inspector insp;
+
+		public BlameBlockInspector(Inspector inspector) {
+			assert inspector != null;
+			insp = inspector;
+		}
+
+		@Override
+		protected void changed(int s1From, int s1To, int s2From, int s2To) {
+			insp.changed(new BlockImpl2(seq1, seq2, s1From, s1To-s1From, s2From, s2To - s2From));
+		}
+		
+		@Override
+		protected void added(int s1InsertPoint, int s2From, int s2To) {
+			insp.added(new BlockImpl2(null, seq2, -1, -1, s2From, s2To - s2From));
+		}
+		
+		@Override
+		protected void deleted(int s1From, int s1To) {
+			insp.deleted(new BlockImpl2(seq1, null, s1From, s1To - s1From, -1, -1));
+		}
+
+		@Override
+		protected void unchanged(int s1From, int s2From, int length) {
+			insp.same(new BlockImpl(seq2, s2From, length));
+		}
+	}
+
+	static class BlockImpl implements Block {
+		private final ChunkSequence seq;
+		private final int start;
+		private final int length;
+		
+		BlockImpl() {
+			// FIXME delete this cons
+			seq = null;
+			start = length = -1;
+		}
+
+		BlockImpl(ChunkSequence s, int blockStart, int blockLength) {
+			seq = s;
+			start = blockStart;
+			length = blockLength;
+		}
+		
+	}
+	
+	static class BlockImpl2 implements ChangeBlock {
+		
+		private final ChunkSequence oldSeq;
+		private final ChunkSequence newSeq;
+		private final int s1Start;
+		private final int s1Len;
+		private final int s2Start;
+		private final int s2Len;
+
+		public BlockImpl2(ChunkSequence s1, ChunkSequence s2, int s1Start, int s1Len, int s2Start, int s2Len) {
+			oldSeq = s1;
+			newSeq = s2;
+			this.s1Start = s1Start;
+			this.s1Len = s1Len;
+			this.s2Start = s2Start;
+			this.s2Len = s2Len;
+		}
+
+		public int firstAddedLine() {
+			return s2Start;
+		}
+
+		public int totalAddedLines() {
+			return s2Len;
+		}
+
+		public String[] addedLines() {
+			return generateLines(totalAddedLines(), firstAddedLine());
+		}
+
+		public int firstRemovedLine() {
+			return s1Start;
+		}
+
+		public int totalRemovedLines() {
+			return s1Len;
+		}
+
+		public String[] removedLines() {
+			return generateLines(totalRemovedLines(), firstRemovedLine());
+		}
+		
+		private String[] generateLines(int count, int startFrom) {
+			String[] rv = new String[count];
+			for (int i = 0; i < count; i++) {
+				rv[i] = String.format("LINE %d", startFrom + i);
+			}
+			return rv;
+		}
+	}
+}