/*------------------------------------------------------------------------------

* Copyright (C) 2003-2006 Ben van Klinken and the CLucene Team

* 

* Distributable under the terms of either the Apache License (Version 2.0) or 

* the GNU Lesser General Public License, as specified in the COPYING file.

------------------------------------------------------------------------------*/

#ifndef _lucene_search_multisearcher

#define _lucene_search_multisearcher

#if defined(_LUCENE_PRAGMA_ONCE)

# pragma once

#endif

#include "clucene/search/searchheader.h"

#include "clucene/document/document.h"

#include "clucene/index/term.h"

CL_NS_DEF(search)

    class MultiHitCollector: public HitCollector{

    private:

      HitCollector* results;

      int32_t start;

    public: 

      MultiHitCollector(HitCollector* _results, int32_t _start);

      void collect(const int32_t doc, const float_t score) ;

    };

 /** Implements search over a set of <code>Searchables</code>.

	*

	* <p>Applications usually need only call the inherited {@link #search(Query)}

	* or {@link #search(Query,Filter)} methods.

	*/

	class MultiSearcher: public Searcher {

  private:

    Searchable** searchables;

		int32_t searchablesLen;

    int32_t* starts;

    int32_t _maxDoc;

	protected:

		int32_t* getStarts() {

  			return starts;

		}

  public:

      /** Creates a searcher which searches <i>Searchables</i>. */

      MultiSearcher(Searchable** searchables);

      ~MultiSearcher();

      /** Frees resources associated with this <code>Searcher</code>. */

      void close() ;

	  int32_t docFreq(const CL_NS(index)::Term* term) const ;

      /** For use by {@link HitCollector} implementations. */

	  bool doc(int32_t n, CL_NS(document)::Document* document);

      /** For use by {@link HitCollector} implementations to identify the

       * index of the sub-searcher that a particular hit came from. */

      int32_t searcherIndex(int32_t n) const;

	  int32_t subSearcher(int32_t n) const;

	  int32_t subDoc(int32_t n) const;

      int32_t maxDoc() const;

      TopDocs* _search(Query* query, Filter* filter, const int32_t nDocs) ;

      TopFieldDocs* _search (Query* query, Filter* filter, const int32_t n, const Sort* sort);

      /** Lower-level search API.

       *

       * <p>{@link HitCollector#collect(int32_t,float_t)} is called for every non-zero

       * scoring document.

       *

       * <p>Applications should only use this if they need <i>all</i> of the

       * matching documents.  The high-level search API ({@link

       * Searcher#search(Query)}) is usually more efficient, as it skips

       * non-high-scoring hits.

       *

       * @param query to match documents

       * @param filter if non-null, a bitset used to eliminate some documents

       * @param results to receive hits

       */

        void _search(Query* query, Filter* filter, HitCollector* results);

		Query* rewrite(Query* original);

		void explain(Query* query, int32_t doc, Explanation* ret);

    };

CL_NS_END

#endif