/*---------------------------------------------------------------------------*
 Project:  Horizon
 File:     SdReaderWriter.cpp

 Copyright 2009 Nintendo.  All rights reserved.

 These coded instructions, statements, and computer programs contain
 proprietary information of Nintendo of America Inc. and/or Nintendo
 Company Ltd., and are protected by Federal copyright law.  They may
 not be disclosed to third parties or copied or duplicated in any form,
 in whole or in part, without the prior written consent of Nintendo.

 $Rev$
 *---------------------------------------------------------------------------*/

#include "SdReaderWriter.h"
#include "SdMountManager.h"
#include "CommonLogger.h"
#include "Aes_define.h"

#include <nn/crypto/crypto_AesCmac.h>
#include <nn/crypto/crypto_SwAesCtrContext.h>
#include <nn/crypto/crypto_Sha256.h>
#include <nn/crypto/crypto_SwAesCmac.h>

#include <cstdlib>

namespace common
{

nn::Result SdReaderWriter::Initialize()
{
    nn::Result result;

    // 初期化済みなら何もしない
    if(m_IsInitialized)
    {
        return nn::ResultSuccess();
    }

    result = SdMountManager::Mount();
    if(result.IsSuccess())
    {
        m_IsInitialized = true;
        return nn::ResultSuccess();
    }
    else
    {
        return result;
    }
}


nn::Result SdReaderWriter::Finalize()
{
    nn::Result result;
    result = SdMountManager::Unmount();

    m_IsInitialized = false;
    return result;
}

nn::Result SdReaderWriter::WriteBufCore(const wchar_t* path, void* buf, size_t size)
{
    NN_ASSERT(path != NULL);
    NN_ASSERT(size > 0);

    nn::Result result = Initialize();
    COMMON_LOGGER_RESULT_IF_FAILED_WITH_LINE(result);

    result = file.TryInitialize(path, nn::fs::OPEN_MODE_WRITE | nn::fs::OPEN_MODE_CREATE);

    if (result.IsSuccess())
    {
        s32 writeSize;
        result = file.TryWrite(&writeSize, buf, size, false);
        if (result.IsSuccess())
        {
            // 何もしない
        }
        else
        {
            NN_LOG("SD TryWrite failed\n");
            COMMON_LOGGER_RESULT_IF_FAILED_WITH_LINE(result);
        }
    }
    else
    {
        NN_LOG("SD TryInitialize failed\n");
        COMMON_LOGGER_RESULT_IF_FAILED_WITH_LINE(result);
    }

    return result;
}

nn::Result SdReaderWriter::WriteBuf(const wchar_t* path, void* buf, size_t size)
{
    nn::Result result;

    result = WriteBufCore(path, buf, size);
    NN_UTIL_RETURN_IF_FAILED(result);

    result = file.TryFlush();
    COMMON_LOGGER_RESULT_IF_FAILED_WITH_LINE(result);
    file.Finalize();

    result = Finalize();
    COMMON_LOGGER_RESULT_IF_FAILED_WITH_LINE(result);

    return result;
}

nn::Result SdReaderWriter::WriteBufWithCmac(const wchar_t* path, void* buf, size_t size)
{
    nn::Result result;

    result = WriteBufCore(path, buf, size);
    NN_UTIL_RETURN_IF_FAILED(result);

    nn::crypto::Initialize();
    bit8 sha256Hash[nn::crypto::Sha256Context::HASH_SIZE];
    nn::crypto::CalculateSha256(sha256Hash, buf, size);

    bit8 cmac[nn::crypto::AES_CMAC_MAC_SIZE];
    result = nn::crypto::CalculateAesCmacSw(cmac, sha256Hash, nn::crypto::Sha256Context::HASH_SIZE, common::cmacKey);
    COMMON_LOGGER_RESULT_IF_FAILED_WITH_LINE(result);

    s32 writeSize;
    result = file.TryWrite(&writeSize, cmac, sizeof(cmac), false);
    COMMON_LOGGER_RESULT_IF_FAILED_WITH_LINE(result);

    result = file.TryFlush();
    COMMON_LOGGER_RESULT_IF_FAILED_WITH_LINE(result);

    file.Finalize();

    result = Finalize();
    COMMON_LOGGER_RESULT_IF_FAILED_WITH_LINE(result);

    return result;

}

nn::Result SdReaderWriter::ReadBufCore(const wchar_t* path, void* buf, size_t size, size_t* totalSize)
{
    NN_ASSERT(path != NULL);
    NN_ASSERT(size > 0);

    nn::Result result;

    if(!m_IsInitialized)
    {
        Initialize();
    }

    result = file.TryInitialize(path, nn::fs::OPEN_MODE_READ);
    if (result.IsSuccess())
    {
        s32 readSize;
        result = file.TryRead(&readSize, buf, size);
        if (result.IsSuccess())
        {
            // TODO バッファを超えるサイズのファイル読み込み
            *totalSize = readSize;
        }
        else
        {
            NN_LOG("SD TryRead failed\n");
            COMMON_LOGGER_RESULT_IF_FAILED_WITH_LINE(result);
        }
    }
    else
    {
        NN_LOG("SD TryInitialize failed\n");
        COMMON_LOGGER_RESULT_IF_FAILED_WITH_LINE(result);
    }

    return result;
}

nn::Result SdReaderWriter::ReadBuf(const wchar_t* path, void* buf, size_t size, size_t* totalSize)
{
    nn::Result result;

    result = ReadBufCore(path, buf, size, totalSize);
    NN_UTIL_RETURN_IF_FAILED(result);

    file.Finalize();
    return result;
}

nn::Result SdReaderWriter::ReadBufWithCmac(const wchar_t* path, void* buf, size_t size, size_t* totalSize)
{
    nn::Result result;

    NN_ASSERT(size > nn::crypto::AES_CMAC_MAC_SIZE);

    result = ReadBufCore(path, buf, size, totalSize);
    NN_UTIL_RETURN_IF_FAILED(result);

    file.Finalize();
    // ハッシュが付加されていない
    if(*totalSize < nn::crypto::AES_CMAC_MAC_SIZE)
    {
        return nn::fs::ResultVerificationFailed();
    }
    *totalSize -= nn::crypto::AES_CMAC_MAC_SIZE;

    // CMACの検証を行う
    nn::crypto::Initialize();
    bit8 sha256Hash[nn::crypto::Sha256Context::HASH_SIZE];
    nn::crypto::CalculateSha256(sha256Hash, buf, *totalSize);

    bit8 cmac[nn::crypto::AES_CMAC_MAC_SIZE];
    result = nn::crypto::CalculateAesCmacSw(cmac, sha256Hash, nn::crypto::Sha256Context::HASH_SIZE, common::cmacKey);
    COMMON_LOGGER_RESULT_IF_FAILED_WITH_LINE(result);

    if(std::memcmp(reinterpret_cast<bit8*>(buf) + *totalSize, cmac, sizeof(cmac)) != 0)
    {
        // 無効なファイル
        char filename[256];
        std::wcstombs(filename, path, sizeof(filename));
        filename[sizeof(filename) - 1] = '\0';
        COMMON_LOGGER("Verification Failed %s\n", filename);
        return nn::fs::ResultVerificationFailed();
    }

    return result;
}

void SdReaderWriter::CreateDirectory(const wchar_t* path)
{
    nn::Result result;

    if(!m_IsInitialized)
    {
        Initialize();
    }

    NN_LOG("Create Directory %ls\n", path);
    result = nn::fs::TryCreateDirectory(path);
    COMMON_LOGGER_RESULT_IF_FAILED_WITH_LINE(result);

    result = Finalize();
    COMMON_LOGGER_RESULT_IF_FAILED_WITH_LINE(result);

}

}