/*********************************************************************
*                                                                    *
* Copyright (c) 1997,1998, 1999                                      *
* Multimedia DB Group and DEIS - CSITE-CNR,                          *
* University of Bologna, Bologna, ITALY.                             *
*                                                                    *
* All Rights Reserved.                                               *
*                                                                    *
* Permission to use, copy, and distribute this software and its      *
* documentation for NON-COMMERCIAL purposes and without fee is       *
* hereby granted provided  that this copyright notice appears in     *
* all copies.                                                        *
*                                                                    *
* THE AUTHORS MAKE NO REPRESENTATIONS OR WARRANTIES ABOUT THE        *
* SUITABILITY OF THE SOFTWARE, EITHER EXPRESS OR IMPLIED, INCLUDING  *
* BUT NOT LIMITED TO THE IMPLIED WARRANTIES OF MERCHANTABILITY,      *
* FITNESS FOR A PARTICULAR PURPOSE, OR NON-INFRINGEMENT. THE AUTHOR  *
* SHALL NOT BE LIABLE FOR ANY DAMAGES SUFFERED BY LICENSEE AS A      *
* RESULT OF USING, MODIFYING OR DISTRIBUTING THIS SOFTWARE OR ITS    *
* DERIVATIVES.                                                       *
*                                                                    *
*********************************************************************/

#ifndef MT_H
#define MT_H

#include "GiST.h"
#include "GiSTentry.h"
#include "MTfile.h"
#include "MTnode.h"
#include "MTcursor.h"
#ifdef _WIN32	// for MAXDOUBLE
#include <float.h>
#include <limits.h>
#define MAXDOUBLE DBL_MAX
#define MINDOUBLE DBL_MIN
#define MAXINT INT_MAX
#else	// under UNIX these constants are defined in values.h
#include <values.h>
#endif

class MTkey;
class TopQuery;
class MTcursor;

typedef enum {
	MIN_R_INCR=0,
	MIN_OVERLAP=1,
	MIXED=2
} tb_function;	// tie breaking functions

typedef enum {
	RANDOM=0,
	CONFIRMED=1,
	MAX_UB_DIST=2,
	MIN_RAD=3,
	MIN_OVERLAPS=4,
	SAMPLING=5,
} pp_function;	// promotion functions

typedef enum {
	RANDOMV=0,
	SAMPLINGV=1,
	MAX_LB_DIST=2,
	mM_RAD=3
} pv_function;	// confirmed promotion functions

typedef enum {
	LB=0,
	AVG=1,
	UB=2
} r_function;	// min_MAX_radius functions

typedef enum {
	G_HYPERPL=0,
	BAL_G_HYPERPL=1,
	BALANCED=2
} s_function;	// split functions

class MT : public GiST {
	unsigned int page;
public:
        MT(unsigned int pagesize) : page(pagesize) {};
	// optional, for debugging support
	GiSTobjid IsA() { return MT_CLASS; }

	int IsOrdered() const { return 1; }	// the children of each node are ordered on increasing distances from the parent
	int MaxLevel() const;	// height of the M-tree
	GiSTlist<MTentry *> RangeSearch(const MTquery& query);	// range search
	MTentry **TopSearch(const TopQuery& query);	// generic search algorithm: k-NN search for a TopQuery
	MTnode *ParentNode(MTnode *node);	// return the parent of node (the caller should delete the object)
	void BulkLoad(MTentry **data, int n, double padFactor, char *name);	// bulk-loading algorithm
	void CollectStats();	// level-stats collecting function: total number of pages, average radius and average covered volume (if applicable)
	BOOL CheckNode(GiSTpath path, MTentry *e);	// debug function: check for node consistency

	// friend methods and functions
	friend void MTnode::InvalidateEntry(BOOL isNew);
	friend GiSTlist<MTentry *> MTnode::RangeSearch(const MTquery& query);
	friend void MTcursor::FetchNode();

protected:
	// Required members
	GiSTnode  *CreateNode()  const { return new MTnode; }
	GiSTstore *CreateStore() const { return new MTfile(page); }

	// Service methods for Bulk Load
	GiSTlist<char *> *SplitTree(int *ncreated, int level, GiSTlist<MTentry *> *children, char *name);	// split this M-tree into a list of M-trees whose names are returned
	void Append(MTnode *to, MTnode *from);	// append the sub-tree of node from to node to
private:
	void AdjKeys(GiSTnode *node);	// slightly different from AdjustKeys (necessary to keep track of the distance from the parent)
};

int PickRandom(int from, int to);	// pick a determined number of samples in the range [from, to[

#endif