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using NGit;
using NGit.Junit;
using NGit.Merge;
using NGit.Notes;
using NGit.Revwalk;
using Sharpen;

namespace NGit.Notes
{
	[NUnit.Framework.TestFixture]
	public class NoteMapMergerTest : RepositoryTestCase
	{
		private TestRepository<Repository> tr;

		private ObjectReader reader;

		private ObjectInserter inserter;

		private NoteMap noRoot;

		private NoteMap empty;

		private NoteMap map_a;

		private NoteMap map_a_b;

		private RevBlob noteAId;

		private string noteAContent;

		private RevBlob noteABlob;

		private RevBlob noteBId;

		private string noteBContent;

		private RevBlob noteBBlob;

		private RevCommit sampleTree_a;

		private RevCommit sampleTree_a_b;

		/// <exception cref="System.Exception"></exception>
		[NUnit.Framework.SetUp]
		public override void SetUp()
		{
			base.SetUp();
			tr = new TestRepository<Repository>(db);
			reader = db.NewObjectReader();
			inserter = db.NewObjectInserter();
			noRoot = NoteMap.NewMap(null, reader);
			empty = NoteMap.NewEmptyMap();
			noteAId = tr.Blob("a");
			noteAContent = "noteAContent";
			noteABlob = tr.Blob(noteAContent);
			sampleTree_a = tr.Commit().Add(noteAId.Name, noteABlob).Create();
			tr.ParseBody(sampleTree_a);
			map_a = NoteMap.Read(reader, sampleTree_a);
			noteBId = tr.Blob("b");
			noteBContent = "noteBContent";
			noteBBlob = tr.Blob(noteBContent);
			sampleTree_a_b = tr.Commit().Add(noteAId.Name, noteABlob).Add(noteBId.Name, noteBBlob
				).Create();
			tr.ParseBody(sampleTree_a_b);
			map_a_b = NoteMap.Read(reader, sampleTree_a_b);
		}

		/// <exception cref="System.Exception"></exception>
		[NUnit.Framework.TearDown]
		public override void TearDown()
		{
			reader.Release();
			inserter.Release();
			base.TearDown();
		}

		/// <exception cref="System.IO.IOException"></exception>
		[NUnit.Framework.Test]
		public virtual void TestNoChange()
		{
			NoteMapMerger merger = new NoteMapMerger(db, null, null);
			NoteMap result;
			NUnit.Framework.Assert.AreEqual(0, CountNotes(merger.Merge(noRoot, noRoot, noRoot
				)));
			NUnit.Framework.Assert.AreEqual(0, CountNotes(merger.Merge(empty, empty, empty)));
			result = merger.Merge(map_a, map_a, map_a);
			NUnit.Framework.Assert.AreEqual(1, CountNotes(result));
			NUnit.Framework.Assert.AreEqual(noteABlob, result.Get(noteAId));
		}

		/// <exception cref="System.Exception"></exception>
		[NUnit.Framework.Test]
		public virtual void TestOursEqualsTheirs()
		{
			NoteMapMerger merger = new NoteMapMerger(db, null, null);
			NoteMap result;
			NUnit.Framework.Assert.AreEqual(0, CountNotes(merger.Merge(empty, noRoot, noRoot)
				));
			NUnit.Framework.Assert.AreEqual(0, CountNotes(merger.Merge(map_a, noRoot, noRoot)
				));
			NUnit.Framework.Assert.AreEqual(0, CountNotes(merger.Merge(noRoot, empty, empty))
				);
			NUnit.Framework.Assert.AreEqual(0, CountNotes(merger.Merge(map_a, empty, empty)));
			result = merger.Merge(noRoot, map_a, map_a);
			NUnit.Framework.Assert.AreEqual(1, CountNotes(result));
			NUnit.Framework.Assert.AreEqual(noteABlob, result.Get(noteAId));
			result = merger.Merge(empty, map_a, map_a);
			NUnit.Framework.Assert.AreEqual(1, CountNotes(result));
			NUnit.Framework.Assert.AreEqual(noteABlob, result.Get(noteAId));
			result = merger.Merge(map_a_b, map_a, map_a);
			NUnit.Framework.Assert.AreEqual(1, CountNotes(result));
			NUnit.Framework.Assert.AreEqual(noteABlob, result.Get(noteAId));
			result = merger.Merge(map_a, map_a_b, map_a_b);
			NUnit.Framework.Assert.AreEqual(2, CountNotes(result));
			NUnit.Framework.Assert.AreEqual(noteABlob, result.Get(noteAId));
			NUnit.Framework.Assert.AreEqual(noteBBlob, result.Get(noteBId));
		}

		/// <exception cref="System.Exception"></exception>
		[NUnit.Framework.Test]
		public virtual void TestBaseEqualsOurs()
		{
			NoteMapMerger merger = new NoteMapMerger(db, null, null);
			NoteMap result;
			NUnit.Framework.Assert.AreEqual(0, CountNotes(merger.Merge(noRoot, noRoot, empty)
				));
			result = merger.Merge(noRoot, noRoot, map_a);
			NUnit.Framework.Assert.AreEqual(1, CountNotes(result));
			NUnit.Framework.Assert.AreEqual(noteABlob, result.Get(noteAId));
			NUnit.Framework.Assert.AreEqual(0, CountNotes(merger.Merge(empty, empty, noRoot))
				);
			result = merger.Merge(empty, empty, map_a);
			NUnit.Framework.Assert.AreEqual(1, CountNotes(result));
			NUnit.Framework.Assert.AreEqual(noteABlob, result.Get(noteAId));
			NUnit.Framework.Assert.AreEqual(0, CountNotes(merger.Merge(map_a, map_a, noRoot))
				);
			NUnit.Framework.Assert.AreEqual(0, CountNotes(merger.Merge(map_a, map_a, empty)));
			result = merger.Merge(map_a, map_a, map_a_b);
			NUnit.Framework.Assert.AreEqual(2, CountNotes(result));
			NUnit.Framework.Assert.AreEqual(noteABlob, result.Get(noteAId));
			NUnit.Framework.Assert.AreEqual(noteBBlob, result.Get(noteBId));
		}

		/// <exception cref="System.Exception"></exception>
		[NUnit.Framework.Test]
		public virtual void TestBaseEqualsTheirs()
		{
			NoteMapMerger merger = new NoteMapMerger(db, null, null);
			NoteMap result;
			NUnit.Framework.Assert.AreEqual(0, CountNotes(merger.Merge(noRoot, empty, noRoot)
				));
			result = merger.Merge(noRoot, map_a, noRoot);
			NUnit.Framework.Assert.AreEqual(1, CountNotes(result));
			NUnit.Framework.Assert.AreEqual(noteABlob, result.Get(noteAId));
			NUnit.Framework.Assert.AreEqual(0, CountNotes(merger.Merge(empty, noRoot, empty))
				);
			result = merger.Merge(empty, map_a, empty);
			NUnit.Framework.Assert.AreEqual(1, CountNotes(result));
			NUnit.Framework.Assert.AreEqual(noteABlob, result.Get(noteAId));
			NUnit.Framework.Assert.AreEqual(0, CountNotes(merger.Merge(map_a, noRoot, map_a))
				);
			NUnit.Framework.Assert.AreEqual(0, CountNotes(merger.Merge(map_a, empty, map_a)));
			result = merger.Merge(map_a, map_a_b, map_a);
			NUnit.Framework.Assert.AreEqual(2, CountNotes(result));
			NUnit.Framework.Assert.AreEqual(noteABlob, result.Get(noteAId));
			NUnit.Framework.Assert.AreEqual(noteBBlob, result.Get(noteBId));
		}

		/// <exception cref="System.Exception"></exception>
		[NUnit.Framework.Test]
		public virtual void TestAddDifferentNotes()
		{
			NoteMapMerger merger = new NoteMapMerger(db, null, null);
			NoteMap result;
			NoteMap map_a_c = NoteMap.Read(reader, sampleTree_a);
			RevBlob noteCId = tr.Blob("c");
			RevBlob noteCBlob = tr.Blob("noteCContent");
			map_a_c.Set(noteCId, noteCBlob);
			map_a_c.WriteTree(inserter);
			result = merger.Merge(map_a, map_a_b, map_a_c);
			NUnit.Framework.Assert.AreEqual(3, CountNotes(result));
			NUnit.Framework.Assert.AreEqual(noteABlob, result.Get(noteAId));
			NUnit.Framework.Assert.AreEqual(noteBBlob, result.Get(noteBId));
			NUnit.Framework.Assert.AreEqual(noteCBlob, result.Get(noteCId));
		}

		/// <exception cref="System.Exception"></exception>
		[NUnit.Framework.Test]
		public virtual void TestAddSameNoteDifferentContent()
		{
			NoteMapMerger merger = new NoteMapMerger(db, new DefaultNoteMerger(), null);
			NoteMap result;
			NoteMap map_a_b1 = NoteMap.Read(reader, sampleTree_a);
			string noteBContent1 = noteBContent + "change";
			RevBlob noteBBlob1 = tr.Blob(noteBContent1);
			map_a_b1.Set(noteBId, noteBBlob1);
			map_a_b1.WriteTree(inserter);
			result = merger.Merge(map_a, map_a_b, map_a_b1);
			NUnit.Framework.Assert.AreEqual(2, CountNotes(result));
			NUnit.Framework.Assert.AreEqual(noteABlob, result.Get(noteAId));
			NUnit.Framework.Assert.AreEqual(tr.Blob(noteBContent + noteBContent1), result.Get
				(noteBId));
		}

		/// <exception cref="System.Exception"></exception>
		[NUnit.Framework.Test]
		public virtual void TestEditSameNoteDifferentContent()
		{
			NoteMapMerger merger = new NoteMapMerger(db, new DefaultNoteMerger(), null);
			NoteMap result;
			NoteMap map_a1 = NoteMap.Read(reader, sampleTree_a);
			string noteAContent1 = noteAContent + "change1";
			RevBlob noteABlob1 = tr.Blob(noteAContent1);
			map_a1.Set(noteAId, noteABlob1);
			map_a1.WriteTree(inserter);
			NoteMap map_a2 = NoteMap.Read(reader, sampleTree_a);
			string noteAContent2 = noteAContent + "change2";
			RevBlob noteABlob2 = tr.Blob(noteAContent2);
			map_a2.Set(noteAId, noteABlob2);
			map_a2.WriteTree(inserter);
			result = merger.Merge(map_a, map_a1, map_a2);
			NUnit.Framework.Assert.AreEqual(1, CountNotes(result));
			NUnit.Framework.Assert.AreEqual(tr.Blob(noteAContent1 + noteAContent2), result.Get
				(noteAId));
		}

		/// <exception cref="System.Exception"></exception>
		[NUnit.Framework.Test]
		public virtual void TestEditDifferentNotes()
		{
			NoteMapMerger merger = new NoteMapMerger(db, null, null);
			NoteMap result;
			NoteMap map_a1_b = NoteMap.Read(reader, sampleTree_a_b);
			string noteAContent1 = noteAContent + "change";
			RevBlob noteABlob1 = tr.Blob(noteAContent1);
			map_a1_b.Set(noteAId, noteABlob1);
			map_a1_b.WriteTree(inserter);
			NoteMap map_a_b1 = NoteMap.Read(reader, sampleTree_a_b);
			string noteBContent1 = noteBContent + "change";
			RevBlob noteBBlob1 = tr.Blob(noteBContent1);
			map_a_b1.Set(noteBId, noteBBlob1);
			map_a_b1.WriteTree(inserter);
			result = merger.Merge(map_a_b, map_a1_b, map_a_b1);
			NUnit.Framework.Assert.AreEqual(2, CountNotes(result));
			NUnit.Framework.Assert.AreEqual(noteABlob1, result.Get(noteAId));
			NUnit.Framework.Assert.AreEqual(noteBBlob1, result.Get(noteBId));
		}

		/// <exception cref="System.Exception"></exception>
		[NUnit.Framework.Test]
		public virtual void TestDeleteDifferentNotes()
		{
			NoteMapMerger merger = new NoteMapMerger(db, null, null);
			NoteMap map_b = NoteMap.Read(reader, sampleTree_a_b);
			map_b.Set(noteAId, null);
			// delete note a
			map_b.WriteTree(inserter);
			NUnit.Framework.Assert.AreEqual(0, CountNotes(merger.Merge(map_a_b, map_a, map_b)
				));
		}

		/// <exception cref="System.Exception"></exception>
		[NUnit.Framework.Test]
		public virtual void TestEditDeleteConflict()
		{
			NoteMapMerger merger = new NoteMapMerger(db, new DefaultNoteMerger(), null);
			NoteMap result;
			NoteMap map_a_b1 = NoteMap.Read(reader, sampleTree_a_b);
			string noteBContent1 = noteBContent + "change";
			RevBlob noteBBlob1 = tr.Blob(noteBContent1);
			map_a_b1.Set(noteBId, noteBBlob1);
			map_a_b1.WriteTree(inserter);
			result = merger.Merge(map_a_b, map_a_b1, map_a);
			NUnit.Framework.Assert.AreEqual(2, CountNotes(result));
			NUnit.Framework.Assert.AreEqual(noteABlob, result.Get(noteAId));
			NUnit.Framework.Assert.AreEqual(noteBBlob1, result.Get(noteBId));
		}

		/// <exception cref="System.Exception"></exception>
		[NUnit.Framework.Test]
		public virtual void TestLargeTreesWithoutConflict()
		{
			NoteMapMerger merger = new NoteMapMerger(db, null, null);
			NoteMap map1 = CreateLargeNoteMap("note_1_", "content_1_", 300, 0);
			NoteMap map2 = CreateLargeNoteMap("note_2_", "content_2_", 300, 0);
			NoteMap result = merger.Merge(empty, map1, map2);
			NUnit.Framework.Assert.AreEqual(600, CountNotes(result));
			// check a few random notes
			NUnit.Framework.Assert.AreEqual(tr.Blob("content_1_59"), result.Get(tr.Blob("note_1_59"
				)));
			NUnit.Framework.Assert.AreEqual(tr.Blob("content_2_10"), result.Get(tr.Blob("note_2_10"
				)));
			NUnit.Framework.Assert.AreEqual(tr.Blob("content_2_99"), result.Get(tr.Blob("note_2_99"
				)));
		}

		/// <exception cref="System.Exception"></exception>
		[NUnit.Framework.Test]
		public virtual void TestLargeTreesWithConflict()
		{
			NoteMapMerger merger = new NoteMapMerger(db, new DefaultNoteMerger(), null);
			NoteMap largeTree1 = CreateLargeNoteMap("note_1_", "content_1_", 300, 0);
			NoteMap largeTree2 = CreateLargeNoteMap("note_1_", "content_2_", 300, 0);
			NoteMap result = merger.Merge(empty, largeTree1, largeTree2);
			NUnit.Framework.Assert.AreEqual(300, CountNotes(result));
			// check a few random notes
			NUnit.Framework.Assert.AreEqual(tr.Blob("content_1_59content_2_59"), result.Get(tr
				.Blob("note_1_59")));
			NUnit.Framework.Assert.AreEqual(tr.Blob("content_1_10content_2_10"), result.Get(tr
				.Blob("note_1_10")));
			NUnit.Framework.Assert.AreEqual(tr.Blob("content_1_99content_2_99"), result.Get(tr
				.Blob("note_1_99")));
		}

		/// <exception cref="System.Exception"></exception>
		private NoteMap CreateLargeNoteMap(string noteNamePrefix, string noteContentPrefix
			, int notesCount, int firstIndex)
		{
			NoteMap result = NoteMap.NewEmptyMap();
			for (int i = 0; i < notesCount; i++)
			{
				result.Set(tr.Blob(noteNamePrefix + (firstIndex + i)), tr.Blob(noteContentPrefix 
					+ (firstIndex + i)));
			}
			result.WriteTree(inserter);
			return result;
		}

		/// <exception cref="System.Exception"></exception>
		[NUnit.Framework.Test]
		public virtual void TestFanoutAndLeafWithoutConflict()
		{
			NoteMapMerger merger = new NoteMapMerger(db, null, null);
			NoteMap largeTree = CreateLargeNoteMap("note_1_", "content_1_", 300, 0);
			NoteMap result = merger.Merge(map_a, map_a_b, largeTree);
			NUnit.Framework.Assert.AreEqual(301, CountNotes(result));
		}

		/// <exception cref="System.Exception"></exception>
		[NUnit.Framework.Test]
		public virtual void TestFanoutAndLeafWitConflict()
		{
			NoteMapMerger merger = new NoteMapMerger(db, new DefaultNoteMerger(), null);
			NoteMap largeTree_b1 = CreateLargeNoteMap("note_1_", "content_1_", 300, 0);
			string noteBContent1 = noteBContent + "change";
			largeTree_b1.Set(noteBId, tr.Blob(noteBContent1));
			largeTree_b1.WriteTree(inserter);
			NoteMap result = merger.Merge(map_a, map_a_b, largeTree_b1);
			NUnit.Framework.Assert.AreEqual(301, CountNotes(result));
			NUnit.Framework.Assert.AreEqual(tr.Blob(noteBContent + noteBContent1), result.Get
				(noteBId));
		}

		/// <exception cref="System.Exception"></exception>
		[NUnit.Framework.Test]
		public virtual void TestCollapseFanoutAfterMerge()
		{
			NoteMapMerger merger = new NoteMapMerger(db, null, null);
			NoteMap largeTree = CreateLargeNoteMap("note_", "content_", 257, 0);
			NUnit.Framework.Assert.IsTrue(largeTree.GetRoot() is FanoutBucket);
			NoteMap deleteFirstHundredNotes = CreateLargeNoteMap("note_", "content_", 157, 100
				);
			NoteMap deleteLastHundredNotes = CreateLargeNoteMap("note_", "content_", 157, 0);
			NoteMap result = merger.Merge(largeTree, deleteFirstHundredNotes, deleteLastHundredNotes
				);
			NUnit.Framework.Assert.AreEqual(57, CountNotes(result));
			NUnit.Framework.Assert.IsTrue(result.GetRoot() is LeafBucket);
		}

		/// <exception cref="System.Exception"></exception>
		[NUnit.Framework.Test]
		public virtual void TestNonNotesWithoutNonNoteConflict()
		{
			NoteMapMerger merger = new NoteMapMerger(db, null, MergeStrategy.RESOLVE);
			RevCommit treeWithNonNotes = tr.Commit().Add(noteAId.Name, noteABlob).Add("a.txt"
				, tr.Blob("content of a.txt")).Create();
			// this is a note
			// this is a non-note
			tr.ParseBody(treeWithNonNotes);
			NoteMap @base = NoteMap.Read(reader, treeWithNonNotes);
			treeWithNonNotes = tr.Commit().Add(noteAId.Name, noteABlob).Add("a.txt", tr.Blob(
				"content of a.txt")).Add("b.txt", tr.Blob("content of b.txt")).Create();
			tr.ParseBody(treeWithNonNotes);
			NoteMap ours = NoteMap.Read(reader, treeWithNonNotes);
			treeWithNonNotes = tr.Commit().Add(noteAId.Name, noteABlob).Add("a.txt", tr.Blob(
				"content of a.txt")).Add("c.txt", tr.Blob("content of c.txt")).Create();
			tr.ParseBody(treeWithNonNotes);
			NoteMap theirs = NoteMap.Read(reader, treeWithNonNotes);
			NoteMap result = merger.Merge(@base, ours, theirs);
			NUnit.Framework.Assert.AreEqual(3, CountNonNotes(result));
		}

		/// <exception cref="System.Exception"></exception>
		[NUnit.Framework.Test]
		public virtual void TestNonNotesWithNonNoteConflict()
		{
			NoteMapMerger merger = new NoteMapMerger(db, null, MergeStrategy.RESOLVE);
			RevCommit treeWithNonNotes = tr.Commit().Add(noteAId.Name, noteABlob).Add("a.txt"
				, tr.Blob("content of a.txt")).Create();
			// this is a note
			// this is a non-note
			tr.ParseBody(treeWithNonNotes);
			NoteMap @base = NoteMap.Read(reader, treeWithNonNotes);
			treeWithNonNotes = tr.Commit().Add(noteAId.Name, noteABlob).Add("a.txt", tr.Blob(
				"change 1")).Create();
			tr.ParseBody(treeWithNonNotes);
			NoteMap ours = NoteMap.Read(reader, treeWithNonNotes);
			treeWithNonNotes = tr.Commit().Add(noteAId.Name, noteABlob).Add("a.txt", tr.Blob(
				"change 2")).Create();
			tr.ParseBody(treeWithNonNotes);
			NoteMap theirs = NoteMap.Read(reader, treeWithNonNotes);
			try
			{
				merger.Merge(@base, ours, theirs);
				NUnit.Framework.Assert.Fail("NotesMergeConflictException was expected");
			}
			catch (NotesMergeConflictException)
			{
			}
		}

		// expected
		private static int CountNotes(NoteMap map)
		{
			int c = 0;
			Iterator<Note> it = map.Iterator();
			while (it.HasNext())
			{
				it.Next();
				c++;
			}
			return c;
		}

		private static int CountNonNotes(NoteMap map)
		{
			int c = 0;
			NonNoteEntry nonNotes = map.GetRoot().nonNotes;
			while (nonNotes != null)
			{
				c++;
				nonNotes = nonNotes.next;
			}
			return c;
		}
	}
}