#ifndef SPX_PARAMS_H
#define SPX_PARAMS_H

/* Hash output length in bytes. */
#define SPX_N 16
/* Height of the hypertree. */
#define SPX_FULL_HEIGHT 64
/* Number of subtree layer. */
#define SPX_D 8
/* FORS tree dimensions. */
#define SPX_FORS_HEIGHT 15
#define SPX_FORS_TREES 10
/* Winternitz parameter, */
#define SPX_WOTS_W 16

/* The hash function is defined by linking a different hash.c file, as opposed
   to setting a #define constant. */

/* For clarity */
#define SPX_ADDR_BYTES 32

/* WOTS parameters. */
#define SPX_WOTS_LOGW 4

#define SPX_WOTS_LEN1 (8 * SPX_N / SPX_WOTS_LOGW)

/* SPX_WOTS_LEN2 is floor(log(len_1 * (w - 1)) / log(w)) + 1; we precompute */
#define SPX_WOTS_LEN2 3

#define SPX_WOTS_LEN (SPX_WOTS_LEN1 + SPX_WOTS_LEN2)
#define SPX_WOTS_BYTES (SPX_WOTS_LEN * SPX_N)
#define SPX_WOTS_PK_BYTES SPX_WOTS_BYTES

/* Subtree size. */
#define SPX_TREE_HEIGHT (SPX_FULL_HEIGHT / SPX_D)

/* FORS parameters. */
#define SPX_FORS_MSG_BYTES ((SPX_FORS_HEIGHT * SPX_FORS_TREES + 7) / 8)
#define SPX_FORS_BYTES ((SPX_FORS_HEIGHT + 1) * SPX_FORS_TREES * SPX_N)
#define SPX_FORS_PK_BYTES SPX_N

/* Resulting SPX sizes. */
#define SPX_BYTES (SPX_N + SPX_FORS_BYTES + SPX_D * SPX_WOTS_BYTES +\
                   SPX_FULL_HEIGHT * SPX_N)
#define SPX_PK_BYTES (2 * SPX_N)
#define SPX_SK_BYTES (2 * SPX_N + SPX_PK_BYTES)

/* Optionally, signing can be made non-deterministic using optrand.
   This can help counter side-channel attacks that would benefit from
   getting a large number of traces when the signer uses the same nodes. */
#define SPX_OPTRAND_BYTES 32

#endif
