#ifndef ODYSSEY_SCRAM_H
#define ODYSSEY_SCRAM_H

#if PG_VERSION_NUM >= 120000
#define od_b64_encode(src, src_len, dst, dst_len)                              \
	pg_b64_encode(src, src_len, dst, dst_len);
#define od_b64_decode(src, src_len, dst, dst_len)                              \
	pg_b64_decode(src, src_len, dst, dst_len);
#else
#define od_b64_encode(src, src_len, dst, dst_len)                              \
	pg_b64_encode(src, src_len, dst);
#define od_b64_decode(src, src_len, dst, dst_len)                              \
	pg_b64_decode(src, src_len, dst);
#endif

/*
 * Odyssey.
 *
 * Scalable PostgreSQL connection pooler.
 */

typedef struct od_scram_state od_scram_state_t;

struct od_scram_state {
	char *client_nonce;
	char *client_first_message;
	char *client_final_message;

	char *server_nonce;
	char *server_first_message;

	uint8_t *salted_password;
	int iterations;
	char *salt;

	uint8_t stored_key[32];
	uint8_t server_key[32];
};

static inline void od_scram_state_init(od_scram_state_t *state)
{
	memset(state, 0, sizeof(*state));
}

static inline void od_scram_state_free(od_scram_state_t *state)
{
	free(state->client_nonce);
	free(state->client_first_message);
	free(state->client_final_message);
	if (state->server_nonce)
		free(state->server_nonce);
	if (state->server_first_message)
		free(state->server_first_message);
	free(state->salted_password);
	free(state->salt);

	memset(state, 0, sizeof(*state));
}

machine_msg_t *
od_scram_create_client_first_message(od_scram_state_t *scram_state);

machine_msg_t *
od_scram_create_client_final_message(od_scram_state_t *scram_state,
				     char *password, char *auth_data,
				     size_t auth_data_size);

machine_msg_t *
od_scram_create_server_first_message(od_scram_state_t *scram_state);

machine_msg_t *
od_scram_create_server_final_message(od_scram_state_t *scram_state);

int od_scram_verify_server_signature(od_scram_state_t *scram_state,
				     char *auth_data, size_t auth_data_size);

int od_scram_verify_final_nonce(od_scram_state_t *scram_state,
				char *final_nonce, size_t final_nonce_size);

int od_scram_verify_client_proof(od_scram_state_t *scram_state,
				 char *client_proof);

int od_scram_parse_verifier(od_scram_state_t *scram_state, char *verifier);

int od_scram_init_from_plain_password(od_scram_state_t *scram_state,
				      char *plain_password);

int od_scram_read_client_first_message(od_scram_state_t *scram_state,
				       char *auth_data, size_t auth_data_size);

int od_scram_read_client_final_message(od_scram_state_t *scram_state,
				       char *auth_data, size_t auth_data_size,
				       char **final_nonce_ptr,
				       size_t *final_nonce_size_ptr,
				       char **proof_ptr);

#endif /* ODYSSEY_SCRAM_H */