// Copyright (c) 2017-2021 Thomas Fussell
//
// Permission is hereby granted, free of charge, to any person obtaining a copy
// of this software and associated documentation files (the "Software"), to deal
// in the Software without restriction, including without limitation the rights
// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
// copies of the Software, and to permit persons to whom the Software is
// furnished to do so, subject to the following conditions:
//
// The above copyright notice and this permission notice shall be included in
// all copies or substantial portions of the Software.
//
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
// THE SOFTWARE
//
// @license: http://www.opensource.org/licenses/mit-license.php
// @author: see AUTHORS file

#include <cstdint>
#include <string>
#include <vector>

#include <detail/cryptography/cipher.hpp>
#include <detail/cryptography/hash.hpp>

namespace xlnt {
namespace detail {

struct encryption_info
{
    bool is_agile = true;

    std::u16string password;

    struct standard_encryption_info
    {
        std::size_t spin_count = 50000;
        std::size_t block_size;
        std::size_t key_bits;
        std::size_t key_bytes;
        std::size_t hash_size;
        cipher_algorithm cipher;
        cipher_chaining chaining;
        hash_algorithm hash = hash_algorithm::sha1;
        std::vector<std::uint8_t> salt;
        std::vector<std::uint8_t> encrypted_verifier;
        std::vector<std::uint8_t> encrypted_verifier_hash;
    } standard;

    struct agile_encryption_info
    {
        // key data
        struct
        {
            std::size_t salt_size;
            std::size_t block_size;
            std::size_t key_bits;
            std::size_t hash_size;
            std::string cipher_algorithm;
            std::string cipher_chaining;
            std::string hash_algorithm;
            std::vector<std::uint8_t> salt_value;
        } key_data;

        struct
        {
            std::vector<std::uint8_t> hmac_key;
            std::vector<std::uint8_t> hmac_value;
        } data_integrity;

        struct
        {
            std::size_t spin_count;
            std::size_t salt_size;
            std::size_t block_size;
            std::size_t key_bits;
            std::size_t hash_size;
            std::string cipher_algorithm;
            std::string cipher_chaining;
            hash_algorithm hash;
            std::vector<std::uint8_t> salt_value;
            std::vector<std::uint8_t> verifier_hash_input;
            std::vector<std::uint8_t> verifier_hash_value;
            std::vector<std::uint8_t> encrypted_key_value;
        } key_encryptor;
    } agile;

    std::vector<std::uint8_t> calculate_key() const;
};

} // namespace detail
} // namespace xlnt