// -*- mode: c; tab-width: 8; indent-tabs-mode: 1; st-rulers: [70] -*-
// vim: ts=8 sw=8 ft=c noet

#include "libsodium_api_crypto_shorthash.h"

static void	LS_API_EXEC(crypto_shorthash, bytes);
static void	LS_API_EXEC(crypto_shorthash, keybytes);
static void	LS_API_EXEC(crypto_shorthash, primitive);
static int	LS_API_INIT(crypto_shorthash, crypto_shorthash);
static void	LS_API_EXEC(crypto_shorthash, crypto_shorthash);

libsodium_function_t	libsodium_functions_crypto_shorthash[] = {
	LS_API_R_ARG0(crypto_shorthash, bytes),
	LS_API_R_ARG0(crypto_shorthash, keybytes),
	LS_API_R_ARG0(crypto_shorthash, primitive),
	LS_API_R_ARGV(crypto_shorthash, crypto_shorthash, 2),
	{NULL}
};

/* crypto_shorthash_bytes/0 */

static void
LS_API_EXEC(crypto_shorthash, bytes)
{
	size_t bytes;

	bytes = crypto_shorthash_bytes();

	ErlDrvTermData spec[] = {
		LS_RES_TAG(request),
		ERL_DRV_UINT, (ErlDrvUInt)(bytes),
		ERL_DRV_TUPLE, 2
	};

	LS_RESPOND(request, spec, __FILE__, __LINE__);
}

/* crypto_shorthash_keybytes/0 */

static void
LS_API_EXEC(crypto_shorthash, keybytes)
{
	size_t keybytes;

	keybytes = crypto_shorthash_keybytes();

	ErlDrvTermData spec[] = {
		LS_RES_TAG(request),
		ERL_DRV_UINT, (ErlDrvUInt)(keybytes),
		ERL_DRV_TUPLE, 2
	};

	LS_RESPOND(request, spec, __FILE__, __LINE__);
}

/* crypto_shorthash_primitive/0 */

static void
LS_API_EXEC(crypto_shorthash, primitive)
{
	const char *primitive;

	primitive = crypto_shorthash_primitive();

	ErlDrvTermData spec[] = {
		LS_RES_TAG(request),
		ERL_DRV_ATOM, driver_mk_atom((char *)(primitive)),
		ERL_DRV_TUPLE, 2
	};

	LS_RESPOND(request, spec, __FILE__, __LINE__);
}

/* crypto_shorthash_crypto_shorthash/1 */

typedef struct LS_API_F_ARGV(crypto_shorthash, crypto_shorthash) {
	const unsigned char	*in;
	unsigned long long	inlen;
	const unsigned char	*k;
} LS_API_F_ARGV_T(crypto_shorthash, crypto_shorthash);

static int
LS_API_INIT(crypto_shorthash, crypto_shorthash)
{
	LS_API_F_ARGV_T(crypto_shorthash, crypto_shorthash) *argv;
	int skip;
	int type;
	int type_length;
	unsigned long long inlen;
	size_t keybytes;
	ErlDrvSizeT x;
	void *p;

	if (ei_get_type(buffer, index, &type, &type_length) < 0
			|| type != ERL_BINARY_EXT) {
		return -1;
	}

	inlen = (unsigned long long)(type_length);

	skip = *index;

	if (ei_skip_term(buffer, &skip) < 0) {
		return -1;
	}

	keybytes = crypto_shorthash_keybytes();

	if (ei_get_type(buffer, &skip, &type, &type_length) < 0
			|| type != ERL_BINARY_EXT
			|| type_length != keybytes) {
		return -1;
	}

	x = (ErlDrvSizeT)(inlen + keybytes + (sizeof (LS_API_F_ARGV_T(crypto_shorthash, crypto_shorthash))));
	p = (void *)(driver_alloc(x));

	if (p == NULL) {
		return -1;
	}

	argv = (LS_API_F_ARGV_T(crypto_shorthash, crypto_shorthash) *)(p);
	p += (sizeof (LS_API_F_ARGV_T(crypto_shorthash, crypto_shorthash)));
	argv->in = (const unsigned char *)(p);
	p += inlen;
	argv->k = (const unsigned char *)(p);

	if (ei_decode_binary(buffer, index, (void *)(argv->in), (long *)&(argv->inlen)) < 0) {
		(void) driver_free(argv);
		return -1;
	}

	if (ei_decode_binary(buffer, index, (void *)(argv->k), NULL) < 0) {
		(void) driver_free(argv);
		return -1;
	}

	request->argv = (void *)(argv);

	return 0;
}

static void
LS_API_EXEC(crypto_shorthash, crypto_shorthash)
{
	LS_API_F_ARGV_T(crypto_shorthash, crypto_shorthash) *argv;
	LS_API_READ_ARGV(crypto_shorthash, crypto_shorthash);
	size_t bytes;
	unsigned char *out;

	bytes = crypto_shorthash_bytes();
	out = (unsigned char *)(driver_alloc((ErlDrvSizeT)(bytes)));

	if (out == NULL) {
		LS_FAIL_OOM(request->port->drv_port);
		return;
	}

	(void) crypto_shorthash(out, argv->in, argv->inlen, argv->k);

	ErlDrvTermData spec[] = {
		LS_RES_TAG(request),
		ERL_DRV_BUF2BINARY, (ErlDrvTermData)(out), bytes,
		ERL_DRV_TUPLE, 2
	};

	LS_RESPOND(request, spec, __FILE__, __LINE__);

	(void) driver_free(out);
}