/*=============================================================================
# Filename: Signature.h
# Author: Bookug Lobert 
# Mail: zengli-bookug@pku.edu.cn
# Last Modified: 2016-04-11 12:50
# Description: written by liyouhuan and hanshuo
=============================================================================*/


#ifndef _SIGNATURE_SIGNATURE_H
#define _SIGNATURE_SIGNATURE_H

#include "../Util/Util.h"

//NOTICE:
//1. it is hard to set the parameter dynamiclly in Signature
//2. unable to bind an edge's neighbor and pre because either pre or neighbor can be a variable in query
class Signature
{
public:
	//NOTICE: the match can be 160 * 3 + 160 * 2
	//or 200 * 3 + 100 * 2
	//TODO: we should adjust the parameter to harvest the best performance

	//static HashFunction hash[HashNum];
	//must make sure:   ENTITY_SIG_LENGTH = EDGE_SIG_LENGTH + STR_SIG_LENGTH 
	//static const unsigned STR_SIG_INTERVAL_NUM = 20;
	//static const unsigned STR_SIG_INTERVAL_NUM = 16;
	//static const unsigned STR_SIG_INTERVAL_BASE = 10;
	//static const unsigned STR_SIG_LITERAL = STR_SIG_INTERVAL_NUM * STR_SIG_INTERVAL_BASE; 
	static const int STR_SIG_LITERAL = 200; 
	static const unsigned STR_SIG_ENTITY = STR_SIG_LITERAL * 2;
	//here we divide as entity neighbors and literal neighbors: ENTITY(in and out), LITERAL(only for out edges)
	static const unsigned STR_SIG_LENGTH = STR_SIG_ENTITY + STR_SIG_LITERAL; //600
	
	//NOTICE: after vstree filter, all constant neighbors will be used again to do precise filtering
	//howvere, only few constant pres will be used again for filtering later
	//So we must make most use of the pres here, while keeping the effect of string part
	//(otherwise the result will be too large)

	//str filter is more important in VSTree than predicate, because
	//a predicate may correspond to a lot of entities and predicate num is usually small
	static const unsigned EDGE_SIG_INTERVAL_NUM_HALF = 10;   //in edge or out edge
	//static const unsigned EDGE_SIG_INTERVAL_NUM_HALF = 16;   //in edge or out edge
	static const unsigned EDGE_SIG_INTERVAL_NUM = 2 * EDGE_SIG_INTERVAL_NUM_HALF;
	static const unsigned EDGE_SIG_INTERVAL_BASE = 10;
	static const unsigned EDGE_SIG_LENGTH = EDGE_SIG_INTERVAL_NUM * EDGE_SIG_INTERVAL_BASE;  //200
	//static const unsigned EDGE_SIG_LENGTH2 = EDGE_SIG_INTERVAL_NUM_HALF * EDGE_SIG_INTERVAL_BASE; 

	static const unsigned STR_AND_EDGE_INTERVAL_BASE = 48;
	static const unsigned STR_AND_EDGE_INTERVAL_NUM = 3;
	static const unsigned STR_AND_EDGE_SIG_LENGTH = STR_AND_EDGE_INTERVAL_BASE * STR_AND_EDGE_INTERVAL_NUM;//144
	static const unsigned SEPARATE_SIG_LENGTH = STR_SIG_LENGTH + EDGE_SIG_LENGTH;
	static const unsigned ENTITY_SIG_LENGTH = SEPARATE_SIG_LENGTH + STR_AND_EDGE_SIG_LENGTH; //944

	//static const unsigned ENTITY_SIG_LENGTH = STR_SIG_LENGTH + EDGE_SIG_LENGTH; //1000
	//static const unsigned ENTITY_SIG_LENGTH = STR_SIG_LENGTH + EDGE_SIG_LENGTH + NEIGHBOR_SIG_LENGTH;

	//QUERY: the num of bitset must be based on 16, i.e. unsigned short?  1000 is not allowed
	//but 800, 500 is ok
	
	//typedef std::bitset<Signature::EDGE_SIG_LENGTH2> EdgeBitSet;
	typedef std::bitset<ENTITY_SIG_LENGTH> EntityBitSet;

	static std::string BitSet2str(const EntityBitSet& _bitset);

	//NOTICE: there are two predicate encoding method now, see the encoding functions @Signature.cpp for details
	const static unsigned PREDICATE_ENCODE_METHOD = 1;
	static void encodePredicate2Entity(EntityBitSet& _entity_bs, TYPE_PREDICATE_ID _pre_id, const char _type);
	static void encodeStr2Entity(EntityBitSet& _entity_bs, TYPE_ENTITY_LITERAL_ID _neighbor_id, const char _type); 
	static void encodeEdge2Entity(EntityBitSet& _entity_bs, TYPE_PREDICATE_ID _pre_id, TYPE_ENTITY_LITERAL_ID _neighbor_id, const char _type);
	//static void encodeStrID2Entity(unsigned _str_id, EntityBitSet& _entity_bs);
	//static void encodePredicate2Edge(unsigned _pre_id, EdgeBitSet& _edge_bs);

	//Signature()
	//{
		//NOTICE:not exceed the HashNum
		//this->hash = new HashFunction[HashNum];
		//this->hash[0] = Util::simpleHash;
		//this->hash[1] = Util::APHash;
		//this->hash[2] = Util::BKDRHash;
		//this->hash[3] = Util::DJBHash;
		//this->hash[4] = Util::ELFHash;
		//this->hash[5] = Util::DEKHash;
		//this->hash[6] = Util::BPHash;
		//this->hash[7] = Util::FNVHash;
		//this->hash[8] = Util::HFLPHash;
		//this->hash[9] = Util::HFHash;
		//this->hash[10] = Util::JSHash;
		//this->hash[11] = Util::PJWHash;
		//this->hash[12] = Util::RSHash;
		//this->hash[13] = Util::SDBMHash;
		//this->hash[14] = Util::StrHash;
		//this->hash[15] = Util::TianlHash;
	//}
	//~Signature()
	//{
		//delete[] this->hash;
	//}
};

//WARN:also defined in Signature, must be same!!!
//NOTICE:EdgeBitSet is only used in Query, not for VSTree
//typedef std::bitset<Signature::EDGE_SIG_LENGTH2> EdgeBitSet;
typedef std::bitset<Signature::ENTITY_SIG_LENGTH> EntityBitSet;

class EntitySig : Signature{
public:
    EntityBitSet entityBitSet;
	EntitySig();
	EntitySig(const EntitySig* _p_sig);
	EntitySig(const EntitySig& _sig);
	EntitySig(const EntityBitSet& _bitset);
	EntitySig& operator|=(const EntitySig& _sig);
	bool operator==(const EntitySig& _sig)const;
	bool operator!=(const EntitySig& _sig)const;
	EntitySig& operator=(const EntitySig& _sig);
	const EntityBitSet& getBitset()const;
	void encode(const char * _str, TYPE_PREDICATE_ID _pre_id);
	std::string to_str() const;
};

//class EdgeSig : Signature{
//public:
    //EdgeBitSet edgeBitSet;
	//EdgeSig();
	//EdgeSig(const EdgeSig* _p_sig);
	//EdgeSig(const EdgeSig& _sig);
	//EdgeSig(const EdgeBitSet& _bitset);
	//EdgeSig& operator|=(const EdgeSig& _sig);
//};

#endif // _SIGNATURE_SIGNATURE_H