/*
 * The Mersenne Twister pseudo-random number generator (PRNG)
 *
 * This is an implementation of fast PRNG called MT19937, meaning it has a
 * period of 2^19937-1, which is a Mersenne prime.
 *
 * This PRNG is fast and suitable for non-cryptographic code.  For instance, it
 * would be perfect for Monte Carlo simulations, etc.
 *
 * For all the details on this algorithm, see the original paper:
 * http://www.math.sci.hiroshima-u.ac.jp/~m-mat/MT/ARTICLES/mt.pdf
 *
 * Written by Christian Stigen Larsen
 * Distributed under the modified BSD license.
 * 2015-02-17, 2017-12-06
 */

#ifndef MERSENNE_TWISTER_H
#define MERSENNE_TWISTER_H

#define __STDC_LIMIT_MACROS
#include <stdint.h>

#define MT_SIZE   624
#define MT_PERIOD 397

typedef struct MTState {
  unsigned int mark;
  unsigned int index;
  uint32_t MT[MT_SIZE];
  uint32_t MT_TEMPERED[MT_SIZE];
} MTState;

/*
 * Extract a pseudo-random unsigned 32-bit integer in the range 0 ... UINT32_MAX
 */
uint32_t mt_rand_u32(MTState *state);

/*
 * Initialize Mersenne Twister with given seed value.
 */
void mt_randseed(MTState *state, const uint32_t *data, size_t len);

void mt_temper(MTState *state);

#endif // MERSENNE_TWISTER_H