#include "CLucene/StdHeader.h"
#ifndef _lucene_index_SegmentMerger_
#define _lucene_index_SegmentMerger_

#include "CLucene/store/Directory.h"
#include "CLucene/document/Document.h"
#include "CLucene/util/BitVector.h"
#include "CLucene/util/VoidList.h"
#include "SegmentMergeInfo.h"
#include "SegmentMergeQueue.h"
#include "FieldInfos.h"
#include "FieldsWriter.h"
#include "TermInfosWriter.h"

namespace lucene{ namespace index {
	class SegmentMerger {
	private:
		Directory& directory;
		const char_t* segment;
		lucene::util::VoidList<SegmentReader*> readers;
		FieldInfos* fieldInfos;

		SegmentMergeQueue* queue;
		lucene::store::OutputStream* freqOutput;
		lucene::store::OutputStream* proxOutput;
		TermInfosWriter* termInfosWriter;
		TermInfo termInfo; //(new) minimize consing
	public:		  
		SegmentMerger(Directory& dir, const char_t* name);
		~SegmentMerger();

		void add(SegmentReader& reader);

		SegmentReader& segmentReader(const int_t i);

		void merge();

	private:
		const char_t* segmentname(const char_t* ext, const int_t x=-1);

		void mergeFields();

		void mergeTerms();

		void mergeTermInfos();

		void mergeTermInfo( SegmentMergeInfo** smis, const int_t n);
		       
		int_t appendPostings(SegmentMergeInfo** smis, const int_t n);

		void mergeNorms();
	};
}}
#endif