/*
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.
 * The ASF licenses this file to You under the Apache License, Version 2.0
 * (the "License"); you may not use this file except in compliance with
 * the License.  You may obtain a copy of the License at
 * 
 * http://www.apache.org/licenses/LICENSE-2.0
 * 
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

using System;
using NUnit.Framework;
using WhitespaceAnalyzer = Lucene.Net.Analysis.WhitespaceAnalyzer;
using Document = Lucene.Net.Documents.Document;
using Field = Lucene.Net.Documents.Field;
using Directory = Lucene.Net.Store.Directory;
using RAMDirectory = Lucene.Net.Store.RAMDirectory;

namespace Lucene.Net.Index
{
	
	[TestFixture]
	public class TestSegmentTermDocs
	{
		private Lucene.Net.Documents.Document testDoc = new Lucene.Net.Documents.Document();
		private Directory dir = new RAMDirectory();
		
        // This is needed if for the test to pass and mimic what happens wiht JUnit
        // For some reason, JUnit is creating a new member variable for each sub-test
        // but NUnit is not -- who is wrong/right, I don't know.
        private void SetUpInternal()        // {{Aroush-1.9}} See note above
        {
		    testDoc = new Lucene.Net.Documents.Document();
		    dir = new RAMDirectory();
        }

		[SetUp]
        public virtual void  SetUp()
		{
            SetUpInternal();    // We need this for NUnit; see note above

			DocHelper.SetupDoc(testDoc);
			DocHelper.WriteDoc(dir, testDoc);
		}
		
		[TearDown]
		public virtual void  TearDown()
		{
			
		}
		
		[Test]
        public virtual void  Test()
		{
			Assert.IsTrue(dir != null);
		}
		
		[Test]
        public virtual void  TestTermDocs()
		{
			//After adding the document, we should be able to read it back in
			SegmentReader reader = SegmentReader.Get(new SegmentInfo("test", 1, dir));
			Assert.IsTrue(reader != null);
			SegmentTermDocs segTermDocs = new SegmentTermDocs(reader);
			Assert.IsTrue(segTermDocs != null);
			segTermDocs.Seek(new Term(DocHelper.TEXT_FIELD_2_KEY, "field"));
			if (segTermDocs.Next() == true)
			{
				int docId = segTermDocs.Doc();
				Assert.IsTrue(docId == 0);
				int freq = segTermDocs.Freq();
				Assert.IsTrue(freq == 3);
			}
			reader.Close();
		}
		
		[Test]
        public virtual void  TestBadSeek()
		{
			{
				//After adding the document, we should be able to read it back in
				SegmentReader reader = SegmentReader.Get(new SegmentInfo("test", 3, dir));
				Assert.IsTrue(reader != null);
				SegmentTermDocs segTermDocs = new SegmentTermDocs(reader);
				Assert.IsTrue(segTermDocs != null);
				segTermDocs.Seek(new Term("textField2", "bad"));
				Assert.IsTrue(segTermDocs.Next() == false);
				reader.Close();
			}
			{
				//After adding the document, we should be able to read it back in
				SegmentReader reader = SegmentReader.Get(new SegmentInfo("test", 3, dir));
				Assert.IsTrue(reader != null);
				SegmentTermDocs segTermDocs = new SegmentTermDocs(reader);
				Assert.IsTrue(segTermDocs != null);
				segTermDocs.Seek(new Term("junk", "bad"));
				Assert.IsTrue(segTermDocs.Next() == false);
				reader.Close();
			}
		}
		
		[Test]
        public virtual void  TestSkipTo()
		{
			Directory dir = new RAMDirectory();
			IndexWriter writer = new IndexWriter(dir, new WhitespaceAnalyzer(), true);
			
			Term ta = new Term("content", "aaa");
			for (int i = 0; i < 10; i++)
				AddDoc(writer, "aaa aaa aaa aaa");
			
			Term tb = new Term("content", "bbb");
			for (int i = 0; i < 16; i++)
				AddDoc(writer, "bbb bbb bbb bbb");
			
			Term tc = new Term("content", "ccc");
			for (int i = 0; i < 50; i++)
				AddDoc(writer, "ccc ccc ccc ccc");
			
			// assure that we deal with a single segment  
			writer.Optimize();
			writer.Close();
			
			IndexReader reader = IndexReader.Open(dir);
			TermDocs tdocs = reader.TermDocs();
			
			// without optimization (assumption skipInterval == 16)
			
			// with next
			tdocs.Seek(ta);
			Assert.IsTrue(tdocs.Next());
			Assert.AreEqual(0, tdocs.Doc());
			Assert.AreEqual(4, tdocs.Freq());
			Assert.IsTrue(tdocs.Next());
			Assert.AreEqual(1, tdocs.Doc());
			Assert.AreEqual(4, tdocs.Freq());
			Assert.IsTrue(tdocs.SkipTo(0));
			Assert.AreEqual(2, tdocs.Doc());
			Assert.IsTrue(tdocs.SkipTo(4));
			Assert.AreEqual(4, tdocs.Doc());
			Assert.IsTrue(tdocs.SkipTo(9));
			Assert.AreEqual(9, tdocs.Doc());
			Assert.IsFalse(tdocs.SkipTo(10));
			
			// without next
			tdocs.Seek(ta);
			Assert.IsTrue(tdocs.SkipTo(0));
			Assert.AreEqual(0, tdocs.Doc());
			Assert.IsTrue(tdocs.SkipTo(4));
			Assert.AreEqual(4, tdocs.Doc());
			Assert.IsTrue(tdocs.SkipTo(9));
			Assert.AreEqual(9, tdocs.Doc());
			Assert.IsFalse(tdocs.SkipTo(10));
			
			// exactly skipInterval documents and therefore with optimization
			
			// with next
			tdocs.Seek(tb);
			Assert.IsTrue(tdocs.Next());
			Assert.AreEqual(10, tdocs.Doc());
			Assert.AreEqual(4, tdocs.Freq());
			Assert.IsTrue(tdocs.Next());
			Assert.AreEqual(11, tdocs.Doc());
			Assert.AreEqual(4, tdocs.Freq());
			Assert.IsTrue(tdocs.SkipTo(5));
			Assert.AreEqual(12, tdocs.Doc());
			Assert.IsTrue(tdocs.SkipTo(15));
			Assert.AreEqual(15, tdocs.Doc());
			Assert.IsTrue(tdocs.SkipTo(24));
			Assert.AreEqual(24, tdocs.Doc());
			Assert.IsTrue(tdocs.SkipTo(25));
			Assert.AreEqual(25, tdocs.Doc());
			Assert.IsFalse(tdocs.SkipTo(26));
			
			// without next
			tdocs.Seek(tb);
			Assert.IsTrue(tdocs.SkipTo(5));
			Assert.AreEqual(10, tdocs.Doc());
			Assert.IsTrue(tdocs.SkipTo(15));
			Assert.AreEqual(15, tdocs.Doc());
			Assert.IsTrue(tdocs.SkipTo(24));
			Assert.AreEqual(24, tdocs.Doc());
			Assert.IsTrue(tdocs.SkipTo(25));
			Assert.AreEqual(25, tdocs.Doc());
			Assert.IsFalse(tdocs.SkipTo(26));
			
			// much more than skipInterval documents and therefore with optimization
			
			// with next
			tdocs.Seek(tc);
			Assert.IsTrue(tdocs.Next());
			Assert.AreEqual(26, tdocs.Doc());
			Assert.AreEqual(4, tdocs.Freq());
			Assert.IsTrue(tdocs.Next());
			Assert.AreEqual(27, tdocs.Doc());
			Assert.AreEqual(4, tdocs.Freq());
			Assert.IsTrue(tdocs.SkipTo(5));
			Assert.AreEqual(28, tdocs.Doc());
			Assert.IsTrue(tdocs.SkipTo(40));
			Assert.AreEqual(40, tdocs.Doc());
			Assert.IsTrue(tdocs.SkipTo(57));
			Assert.AreEqual(57, tdocs.Doc());
			Assert.IsTrue(tdocs.SkipTo(74));
			Assert.AreEqual(74, tdocs.Doc());
			Assert.IsTrue(tdocs.SkipTo(75));
			Assert.AreEqual(75, tdocs.Doc());
			Assert.IsFalse(tdocs.SkipTo(76));
			
			//without next
			tdocs.Seek(tc);
			Assert.IsTrue(tdocs.SkipTo(5));
			Assert.AreEqual(26, tdocs.Doc());
			Assert.IsTrue(tdocs.SkipTo(40));
			Assert.AreEqual(40, tdocs.Doc());
			Assert.IsTrue(tdocs.SkipTo(57));
			Assert.AreEqual(57, tdocs.Doc());
			Assert.IsTrue(tdocs.SkipTo(74));
			Assert.AreEqual(74, tdocs.Doc());
			Assert.IsTrue(tdocs.SkipTo(75));
			Assert.AreEqual(75, tdocs.Doc());
			Assert.IsFalse(tdocs.SkipTo(76));
			
			tdocs.Close();
			reader.Close();
			dir.Close();
		}
		
		private void  AddDoc(IndexWriter writer, System.String value_Renamed)
		{
			Lucene.Net.Documents.Document doc = new Lucene.Net.Documents.Document();
			doc.Add(new Field("content", value_Renamed, Field.Store.NO, Field.Index.TOKENIZED));
			writer.AddDocument(doc);
		}
	}
}