using System;
using Lucene.Net.Index;
using Lucene.Net.Search;
using NUnit.Framework;

namespace dotLucene.inAction.Index
{

	[TestFixture]
	public class DocumentDeleteTest : BaseIndexingTestCase
	{
		[Test]
		public void testDeleteBeforeIndexMerge()
		{
	
			IndexReader reader = IndexReader.Open(dir);  //當前索引中有兩個Document

			Assert.AreEqual(2, reader.MaxDoc());        //文檔從0開始計數,MaxDoc表示下一個文檔的序號
			Assert.AreEqual(2, reader.NumDocs());       //NumDocs表示當前索引中文檔的個數  
			reader.Delete(1);							//對標號為1的文檔標記為待刪除,邏輯刪除
			Assert.IsTrue(reader.IsDeleted(1));         //檢測某個序號的文檔是否被標記刪除
			Assert.IsTrue(reader.HasDeletions());       //檢測索引中是否有Document被標記刪除 
			Assert.AreEqual(2, reader.MaxDoc());        //當前下一個文檔序號仍然為2
			Assert.AreEqual(1, reader.NumDocs());       //當前索引中文檔數變成1
			reader.Close();                             //此時真正從物理上刪除之前被標記的文檔
			reader = IndexReader.Open(dir);
			Assert.AreEqual(2, reader.MaxDoc());         
			Assert.AreEqual(1, reader.NumDocs());
			reader.Close();
		}

		[Test]
		public void DeleteAfterIndexMerge()            //在索引重排之后
		{

			IndexReader reader = IndexReader.Open(dir);
			Assert.AreEqual(2, reader.MaxDoc());
			Assert.AreEqual(2, reader.NumDocs());
			reader.Delete(1);
			reader.Close();
			IndexWriter writer = new IndexWriter(dir, GetAnalyzer(), false);
			writer.Optimize();                          //索引重排
			writer.Close();
			reader = IndexReader.Open(dir);
       
			Assert.IsFalse(reader.IsDeleted(1));
			Assert.IsFalse(reader.HasDeletions());
			Assert.AreEqual(1, reader.MaxDoc());       //索引重排后,下一個文檔序號變為1
			Assert.AreEqual(1, reader.NumDocs());
			reader.Close();
		}
	}
}