//---------------------------------------------------------------------------
#include <vcl.h>
#include <stdlib.h>
#include <time.h>
#pragma hdrstop

#include "TexpiaRandom.h"
//---------------------------------------------------------------------------
#pragma package(smart_init)
//---------------------------------------------------------------------------
int TTexpiaRandom::Instance = 0;
unsigned char *TTexpiaRandom::Index = NULL;
int *TTexpiaRandom::Value = NULL;
int TTexpiaRandom::Count = 0;
//---------------------------------------------------------------------------
// Private Function
//---------------------------------------------------------------------------
void __fastcall TTexpiaRandom::Exit()
{
  if (Value) { delete Value; Value = NULL; }
  if (Index) { delete Index; Index = NULL; }
  Count = 0;
}
//---------------------------------------------------------------------------
// Public Function
//---------------------------------------------------------------------------
__fastcall TTexpiaRandom::TTexpiaRandom(int c)
{
	Instance++;
  if (Count) Seed(); else Init(c);
}
//---------------------------------------------------------------------------
__fastcall TTexpiaRandom::~TTexpiaRandom()
{
	Instance--;
  if (Instance==0) Exit();
}
//---------------------------------------------------------------------------
bool __fastcall TTexpiaRandom::Init(int c)
{
	c = 1 << c;
	if (Count) Exit();
  if ((Index = new unsigned char[c])==NULL) goto fail;
  if ((Value = new int[c])==NULL) goto fail;
  Count = c-1;
  Seed();
  return true;
fail:
  Exit();
  return false;
}
//---------------------------------------------------------------------------
void __fastcall TTexpiaRandom::Seed()
{
  srand(clock());
  int *vp = Value;
  unsigned char *ip = Index;
  for (int i=0; i<=Count; i++) {
    *vp++ = rand();
    *ip++ = rand()&0xFF;
  }
  vn = rand()&Count;
  in = rand()&Count;
}
//---------------------------------------------------------------------------
int __fastcall TTexpiaRandom::Get(int r)
{
  in++;
  in &= Count;
  vn += Index[in];
  vn &= Count;
  return Value[vn]%r;
}
//---------------------------------------------------------------------------