/*
* Copyright (c) 2023 Vaughn Nugent
*
* vnlib_monocypher is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published
* by the Free Software Foundation, either version 2 of the License,
* or (at your option) any later version.
*
* vnlib_monocypher is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with vnlib_monocypher. If not, see http://www.gnu.org/licenses/.
*/

#include "argon2.h"
#include <monocypher.h>

VNLIB_EXPORT uint32_t VNLIB_CC Argon2CalcWorkAreaSize(const argon2Ctx* context)
{
	return context->m_cost * 1024;
}

/*
* The purpose of this function is to remap the Argon2 context/function call
* interface to the Monocypher library version. Also performing some basic
* input validation that also matches the Argon2 library.
*/

VNLIB_EXPORT argon2_error_codes VNLIB_CC Argon2ComputeHash(const argon2Ctx* context, void* workArea)
{
	crypto_argon2_config config;
	crypto_argon2_inputs inputs;
	crypto_argon2_extras extras;

	if (!context || !workArea)
	{
		return ERR_INVALID_PTR;
	}

	config.algorithm = context->version;
	config.nb_blocks = context->m_cost;	
	config.nb_passes = context->t_cost;
	config.nb_lanes = context->threads;	

	inputs.pass_size = context->pwdlen;
	inputs.pass = context->pwd;

	inputs.salt_size = context->saltlen;
	inputs.salt = context->salt;

	/* must specify a password input */
	if (inputs.pass_size < 1)
	{
		return ARGON2_PWD_TOO_SHORT;
	}

	if (!inputs.pass)
	{
		return ARGON2_PWD_PTR_MISMATCH;
	}

	if (inputs.salt_size < 1)
	{
		return ARGON2_SALT_TOO_SHORT;
	}

	/* Verify salt pointer 1is not invalid  */
	if (!inputs.salt)
	{
		return ARGON2_SALT_PTR_MISMATCH;
	}

	extras.ad = context->ad;
	extras.ad_size = context->adlen;

	extras.key = context->secret;
	extras.key_size = context->secretlen;

	//If key is set, verify a valid pointer
	if (extras.key_size > 0 && !extras.key)
	{
		return ARGON2_SECRET_PTR_MISMATCH;
	}

	if (context->outlen < 1)
	{
		return ARGON2_OUTPUT_TOO_SHORT;
	}

	if (!context->out)
	{
		return ARGON2_OUTPUT_PTR_NULL;
	}

	/* invoke lib function */
	crypto_argon2(context->out, context->outlen, workArea, config, inputs, extras);

	return ARGON2_OK;
}