#ifndef BLAKE2_H
#define BLAKE2_H

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

#if defined(_MSC_VER)
#define BLAKE2_PACKED(x) __pragma(pack(push, 1)) x __pragma(pack(pop))
#else
#define BLAKE2_PACKED(x) x __attribute__((packed))
#endif

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

enum blake2b_constant {
	BLAKE2B_BLOCKBYTES = 128,
	BLAKE2B_OUTBYTES = 64,
	BLAKE2B_KEYBYTES = 64,
	BLAKE2B_SALTBYTES = 16,
	BLAKE2B_PERSONALBYTES = 16
};

typedef struct blake2s_state__ {
	uint32_t h[8];
	uint32_t t[2];
	uint32_t f[2];
	uint8_t buf[BLAKE2S_BLOCKBYTES];
	size_t buflen;
	size_t outlen;
	uint8_t last_node;
} blake2s_state;

typedef struct blake2b_state__ {
	uint64_t h[8];
	uint64_t t[2];
	uint64_t f[2];
	uint8_t buf[BLAKE2B_BLOCKBYTES];
	size_t buflen;
	size_t outlen;
	uint8_t last_node;
} blake2b_state;

typedef struct blake2sp_state__ {
	blake2s_state S[8][1];
	blake2s_state R[1];
	uint8_t buf[8 * BLAKE2S_BLOCKBYTES];
	size_t buflen;
	size_t outlen;
} blake2sp_state;

typedef struct blake2bp_state__ {
	blake2b_state S[4][1];
	blake2b_state R[1];
	uint8_t buf[4 * BLAKE2B_BLOCKBYTES];
	size_t buflen;
	size_t outlen;
} blake2bp_state;


BLAKE2_PACKED(struct blake2s_param__ {
	      uint8_t digest_length;	/* 1 */
	      uint8_t key_length;	/* 2 */
	      uint8_t fanout;	/* 3 */
	      uint8_t depth;	/* 4 */
	      uint32_t leaf_length;	/* 8 */
	      uint32_t node_offset;	/* 12 */
	      uint16_t xof_length;	/* 14 */
	      uint8_t node_depth;	/* 15 */
	      uint8_t inner_length;	/* 16 */
	      /* uint8_t  reserved[0]; */
	      uint8_t salt[BLAKE2S_SALTBYTES];	/* 24 */
	      uint8_t personal[BLAKE2S_PERSONALBYTES];	/* 32 */
	      });

typedef struct blake2s_param__ blake2s_param;

BLAKE2_PACKED(struct blake2b_param__ {
	      uint8_t digest_length;	/* 1 */
	      uint8_t key_length;	/* 2 */
	      uint8_t fanout;	/* 3 */
	      uint8_t depth;	/* 4 */
	      uint32_t leaf_length;	/* 8 */
	      uint32_t node_offset;	/* 12 */
	      uint32_t xof_length;	/* 16 */
	      uint8_t node_depth;	/* 17 */
	      uint8_t inner_length;	/* 18 */
	      uint8_t reserved[14];	/* 32 */
	      uint8_t salt[BLAKE2B_SALTBYTES];	/* 48 */
	      uint8_t personal[BLAKE2B_PERSONALBYTES];	/* 64 */
	      });

typedef struct blake2b_param__ blake2b_param;

typedef struct blake2xs_state__ {
	blake2s_state S[1];
	blake2s_param P[1];
} blake2xs_state;

typedef struct blake2xb_state__ {
	blake2b_state S[1];
	blake2b_param P[1];
} blake2xb_state;

  /* Padded structs result in a compile-time error */
enum {
	BLAKE2_DUMMY_1 = 1 / (sizeof(blake2s_param) == BLAKE2S_OUTBYTES),
	BLAKE2_DUMMY_2 = 1 / (sizeof(blake2b_param) == BLAKE2B_OUTBYTES)
};

  /* Streaming API */
int blake2s_init(blake2s_state * S, size_t outlen);
int blake2s_init_key(blake2s_state * S, size_t outlen, const void *key,
		     size_t keylen);
int blake2s_init_param(blake2s_state * S, const blake2s_param * P);
int blake2s_update(blake2s_state * S, const void *in, size_t inlen);
int blake2s_final(blake2s_state * S, void *out, size_t outlen);

int blake2b_init(blake2b_state * S, size_t outlen);
int blake2b_init_key(blake2b_state * S, size_t outlen, const void *key,
		     size_t keylen);
int blake2b_init_param(blake2b_state * S, const blake2b_param * P);
int blake2b_update(blake2b_state * S, const void *in, size_t inlen);
int blake2b_final(blake2b_state * S, void *out, size_t outlen);

int blake2sp_init(blake2sp_state * S, size_t outlen);
int blake2sp_init_key(blake2sp_state * S, size_t outlen, const void *key,
		      size_t keylen);
int blake2sp_update(blake2sp_state * S, const void *in, size_t inlen);
int blake2sp_final(blake2sp_state * S, void *out, size_t outlen);

int blake2bp_init(blake2bp_state * S, size_t outlen);
int blake2bp_init_key(blake2bp_state * S, size_t outlen, const void *key,
		      size_t keylen);
int blake2bp_update(blake2bp_state * S, const void *in, size_t inlen);
int blake2bp_final(blake2bp_state * S, void *out, size_t outlen);

  /* Variable output length API */
int blake2xs_init(blake2xs_state * S, const size_t outlen);
int blake2xs_init_key(blake2xs_state * S, const size_t outlen,
		      const void *key, size_t keylen);
int blake2xs_update(blake2xs_state * S, const void *in, size_t inlen);
int blake2xs_final(blake2xs_state * S, void *out, size_t outlen);

int blake2xb_init(blake2xb_state * S, const size_t outlen);
int blake2xb_init_key(blake2xb_state * S, const size_t outlen,
		      const void *key, size_t keylen);
int blake2xb_update(blake2xb_state * S, const void *in, size_t inlen);
int blake2xb_final(blake2xb_state * S, void *out, size_t outlen);

  /* Simple API */
int blake2s(void *out, size_t outlen, const void *in, size_t inlen,
	    const void *key, size_t keylen);
int blake2b(void *out, size_t outlen, const void *in, size_t inlen,
	    const void *key, size_t keylen);

int blake2sp(void *out, size_t outlen, const void *in, size_t inlen,
	     const void *key, size_t keylen);
int blake2bp(void *out, size_t outlen, const void *in, size_t inlen,
	     const void *key, size_t keylen);

int blake2xs(void *out, size_t outlen, const void *in, size_t inlen,
	     const void *key, size_t keylen);
int blake2xb(void *out, size_t outlen, const void *in, size_t inlen,
	     const void *key, size_t keylen);

  /* This is simply an alias for blake2b */
int blake2(void *out, size_t outlen, const void *in, size_t inlen,
	   const void *key, size_t keylen);

#endif