#ifndef __BLAKE2S_H__
#define __BLAKE2S_H__

#include <stddef.h>
#include <stdint.h>

enum blake2s_constant {
  BLAKE2S_BLOCKBYTES = 64,
  BLAKE2S_OUTBYTES = 32,
  BLAKE2S_KEYBYTES = 32,
  BLAKE2S_SALTBYTES = 8,
  BLAKE2S_PERSONALBYTES = 8
};

typedef struct __blake2s_state {
  uint32_t h[8];
  uint32_t t[2];
  uint32_t f[2];
  uint8_t buf[BLAKE2S_BLOCKBYTES];
  uint32_t buflen;
  uint8_t outlen;
  uint8_t last_node;
} blake2s_state;

#define BLAKE2S_CTX blake2s_state
#define BLAKE2S_BLOCK_LENGTH BLAKE2S_BLOCKBYTES
#define BLAKE2S_DIGEST_LENGTH BLAKE2S_OUTBYTES
#define BLAKE2S_KEY_LENGTH BLAKE2S_KEYBYTES

int blake2s_Init(blake2s_state *S, size_t outlen);
int blake2s_InitKey(blake2s_state *S, size_t outlen, const void *key,
                    size_t keylen);
int blake2s_InitPersonal(blake2s_state *S, size_t outlen, const void *personal,
                         size_t personal_len);
int blake2s_Update(blake2s_state *S, const void *pin, size_t inlen);
int blake2s_Final(blake2s_state *S, void *out, size_t outlen);

int blake2s(const uint8_t *msg, uint32_t msg_len, void *out, size_t outlen);
int blake2s_Key(const uint8_t *msg, uint32_t msg_len, const void *key,
                size_t keylen, void *out, size_t outlen);

#endif