/************************************************
*
* read table data to memory
*
* create zoufuzhou 20201001
*
************************************************/
#ifndef _DATABASE_TO_MEM_CACHE_HPP_
#define _DATABASE_TO_MEM_CACHE_HPP_

#include <glob/GlobMem.h>

template <class T,typename S> class DB2Mem
{
  typedef struct{
    unsigned int maxsize;
    unsigned int size;
    unsigned int count;
  }HEAD;

	private:
    HEAD*   p_head;
    S*      p_ptr;
	public:
		DB2Mem(const string& tableName)
		{
			char* ptr = (char*)GlobMem::GetInstancePtr()->GetTablePtr(tableName);
			if(ptr == nullptr)
			{
				 p_ptr = nullptr;
				 p_head = nullptr;
				 return;
			}
      p_head = (HEAD*)(ptr);
      p_ptr  = (S*)(ptr+sizeof(HEAD));
      p_head->maxsize = 100;
		}
		~DB2Mem()
		{
			return;
		}
	public:

		S* operator()(void)
		{
			return p_ptr;
		};

		S* operator[](int i)
		{
			if(p_ptr == nullptr) return nullptr;
			return p_ptr+i;
		};

		long count(void)
		{
			if(p_head == nullptr)return 0;
			return p_head->size;
		};


		/* Read DB Table Data to memory */
		int readDB(char* dbwhere = nullptr,char* order = nullptr)
		{
			if( p_ptr == nullptr ) {
				return -1;
			}

			p_head->size = 0;

			T	tb;
			char* dbMsg = tb.openSetDB(dbwhere,order);
			if( dbMsg != nullptr)
			{
				tb.closeSetDB();
				return -1;
			}

			while( ( dbMsg = tb.getSetDB()) == nullptr )
			{
				tb.fillStructure();
				memcpy(p_ptr+p_head->size,&tb.structTable,sizeof(S));
				p_head->size = p_head->size+1;
        p_head->count++;
			}
      p_head->maxsize =  p_head->size+1;

			return 0;
		}
};

#endif