//! \addtogroup Core
//! \{
//! \file pidigest.h
//! \brief
//! \~english Digest algorithms
//! \~russian Алгоритмы хэш-сумм
//!
//! \details
//! \~english
//! This file implements several common-usage hash algorithms
//! \~russian
//! Этот файл реализует несколько распространенных алгоритмов хэширования
//! \}
/*
    PIP - Platform Independent Primitives
    Digest algorithms
    Ivan Pelipenko peri4ko@yandex.ru

    This program is free software: you can redistribute it and/or modify
    it under the terms of the GNU Lesser General Public License as published by
    the Free Software Foundation, either version 3 of the License, or
    (at your option) any later version.

    This program 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 Lesser General Public License for more details.

    You should have received a copy of the GNU Lesser General Public License
    along with this program.  If not, see <http://www.gnu.org/licenses/>.
*/

#ifndef pidigest_h
#define pidigest_h

#include "pibytearray.h"
#include "piconstchars.h"

class PIP_EXPORT PIDigest {
public:
	//! \~english Hash algorithm type
	//! \~russian Тип алгоритма хэширования
	//! \details
	//! \~english
	//! Supported algorithms: SHA1, SHA2 family (224, 256, 384, 512, 512_224, 512_256),
	//! MD2, MD4, MD5, BLAKE2s, BLAKE2b, SipHash
	//! \~russian
	//! Поддерживаемые алгоритмы: SHA1, семейство SHA2 (224, 256, 384, 512, 512_224, 512_256),
	//! MD2, MD4, MD5, BLAKE2s, BLAKE2b, SipHash
	enum class Type {
		SHA1,

		SHA2_224,
		SHA2_256,
		SHA2_384,
		SHA2_512,
		SHA2_512_224,
		SHA2_512_256,

		MD2,
		MD4,
		MD5,

		BLAKE2s_128,
		BLAKE2s_160,
		BLAKE2s_224,
		BLAKE2s_256,
		BLAKE2b_128,
		BLAKE2b_160,
		BLAKE2b_224,
		BLAKE2b_256,
		BLAKE2b_384,
		BLAKE2b_512,

		SipHash_2_4_64,
		SipHash_2_4_128,
		HalfSipHash_2_4_32,
		HalfSipHash_2_4_64,

		Count,
	};

	//! \~english Get hash output length in bytes
	//! \~russian Получить длину хэша в байтах
	static int hashLength(Type type);
	//! \~english Get hash block length in bytes
	//! \~russian Получить длину блока хэширования в байтах
	static int blockLength(Type type);
	//! \~english Get algorithm name as string
	//! \~russian Получить название алгоритма в виде строки
	//! \return Algorithm name
	//! \sa Type
	static PIConstChars typeName(Type type);

	//! \~english Calculate hash of message
	//! \~russian Вычислить хэш сообщения
	//! \param msg Input message
	//! \param type Hash algorithm type
	//! \return Hash bytes
	//! \sa calculateWithKey, HMAC
	static PIByteArray calculate(const PIByteArray & msg, Type type);
	//! \~english Calculate keyed hash of message
	//! \~russian Вычислить ключевой хэш сообщения
	//! \param msg Input message
	//! \param key Secret key
	//! \param type Hash algorithm type (SipHash or BLAKE2)
	//! \return Hash bytes
	//! \note Only SipHash and BLAKE2 algorithms support keyed hashing
	//! \sa calculate, HMAC
	static PIByteArray calculateWithKey(const PIByteArray & msg, const PIByteArray & key, Type type);
	//! \~english Calculate HMAC (Keyed-Hash Message Authentication Code)
	//! \~russian Вычислить HMAC (код аутентификации сообщений на основе ключа)
	//! \param msg Input message
	//! \param key Secret key
	//! \param type Hash algorithm type
	//! \return HMAC bytes
	//! \note Supports SHA1, SHA2 and MD5 algorithms
	//! \sa calculate, calculateWithKey
	static PIByteArray HMAC(const PIByteArray & msg, const PIByteArray & key, PIDigest::Type type);
};

//! \}

#endif