/****************************************************************************
*                                                                           *
* Project64 - A Nintendo 64 emulator.                                      *
* http://www.pj64-emu.com/                                                  *
* Copyright (C) 2012 Project64. All rights reserved.                        *
*                                                                           *
* License:                                                                  *
* GNU/GPLv2 http://www.gnu.org/licenses/gpl-2.0.html                        *
*                                                                           *
****************************************************************************/
#include "stdafx.h"
#include "Mempak.H"
#include <Common/path.h>
#include <Windows.h>

static uint8_t Mempaks[4][0x8000];
HANDLE hMempakFile[4];

void Mempak::Close()
{
    for (int i = 0; i < 4; i++)
    {
        if (hMempakFile[i])
        {
            CloseHandle(hMempakFile[i]);
            hMempakFile[i] = NULL;
        }
    }
}

void LoadMempak(int Control)
{
    CPath FileName;
    DWORD dwRead;
    stdstr MempakName;
    bool bFormatMempak = false;

    MempakName.Format("%s_Cont_%d", g_Settings->LoadStringVal(Game_GameName).c_str(), Control + 1);

    FileName.SetDriveDirectory(g_Settings->LoadStringVal(Directory_NativeSave).c_str());
    FileName.SetName(MempakName.c_str());
    FileName.SetExtension("mpk");

    if (!FileName.Exists())
    {
        bFormatMempak = true;

        if (!FileName.DirectoryExists())
        {
            FileName.DirectoryCreate();
        }

        uint8_t Initialize[] = {
            0x81, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07, 0x08, 0x09, 0x0a, 0x0b, 0x0C, 0x0D, 0x0E, 0x0F,
            0x10, 0x11, 0x12, 0x13, 0x14, 0x15, 0x16, 0x17, 0x18, 0x19, 0x1A, 0x1B, 0x1C, 0x1D, 0x1E, 0x1F,
            0xFF, 0xFF, 0xFF, 0xFF, 0x05, 0x1A, 0x5F, 0x13, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
            0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0x01, 0xFF, 0x66, 0x25, 0x99, 0xCD,
            0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
            0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
            0xFF, 0xFF, 0xFF, 0xFF, 0x05, 0x1A, 0x5F, 0x13, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
            0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0x01, 0xFF, 0x66, 0x25, 0x99, 0xCD,
            0xFF, 0xFF, 0xFF, 0xFF, 0x05, 0x1A, 0x5F, 0x13, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
            0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0x01, 0xFF, 0x66, 0x25, 0x99, 0xCD,
            0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
            0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
            0xFF, 0xFF, 0xFF, 0xFF, 0x05, 0x1A, 0x5F, 0x13, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
            0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0x01, 0xFF, 0x66, 0x25, 0x99, 0xCD,
            0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
            0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
            0x00, 0x71, 0x00, 0x03, 0x00, 0x03, 0x00, 0x03, 0x00, 0x03, 0x00, 0x03, 0x00, 0x03, 0x00, 0x03,
        };

        memcpy(&Mempaks[Control][0], Initialize, 0x110);

        for (int count = 0x110; count < 0x8000; count += 2)
        {
            Mempaks[Control][count] = 0x00;
            Mempaks[Control][count + 1] = 0x03;
        }
    }

    hMempakFile[Control] = CreateFile(FileName, GENERIC_WRITE | GENERIC_READ, FILE_SHARE_READ, NULL, OPEN_ALWAYS, FILE_ATTRIBUTE_NORMAL | FILE_FLAG_RANDOM_ACCESS, NULL);

    if (hMempakFile[Control] == INVALID_HANDLE_VALUE)
    {
        WriteTrace(TraceN64System, TraceError, "Failed to open (%s), lastError = %X", (LPCTSTR)FileName, GetLastError());
        return;
    }

    SetFilePointer(hMempakFile[Control], 0, NULL, FILE_BEGIN);
    if (bFormatMempak)
    {
        WriteFile(hMempakFile[Control], Mempaks[Control], 0x8000, &dwRead, NULL);
    }
    else
    {
        ReadFile(hMempakFile[Control], Mempaks[Control], 0x8000, &dwRead, NULL);
    }
}

uint8_t Mempak::CalculateCrc(uint8_t * DataToCrc)
{
    DWORD Count;
    DWORD XorTap;

    int Length;
    uint8_t CRC = 0;

    for (Count = 0; Count < 0x21; Count++)
    {
        for (Length = 0x80; Length >= 1; Length >>= 1)
        {
            XorTap = (CRC & 0x80) ? 0x85 : 0x00;
            CRC <<= 1;
            if (Count == 0x20)
            {
                CRC &= 0xFF;
            }
            else
            {
                if ((*DataToCrc & Length) != 0)
                {
                    CRC |= 1;
                }
            }
            CRC ^= XorTap;
        }
        DataToCrc++;
    }

    return CRC;
}

void Mempak::ReadFrom(int Control, uint8_t * command)
{
    DWORD address = (command[3] << 8) | (command[4] & 0xE0);

    if (address < 0x8000)
    {
        if (hMempakFile[Control] == NULL)
        {
            LoadMempak(Control);
        }
        memcpy(&command[5], &Mempaks[Control][address], 0x20);
    }
    else
    {
        memset(&command[5], 0x00, 0x20);
        /* Rumble pack area */
    }
}

void Mempak::WriteTo(int Control, uint8_t * command)
{
    DWORD dwWritten;
    uint32_t address = (command[3] << 8) | (command[4] & 0xE0);

    if (address < 0x8000)
    {
        if (hMempakFile[Control] == NULL)
        {
            LoadMempak(Control);
        }
        memcpy(&Mempaks[Control][address], &command[5], 0x20);

        SetFilePointer(hMempakFile[Control], 0, NULL, FILE_BEGIN);
        WriteFile(hMempakFile[Control], &Mempaks[Control][0], 0x8000, &dwWritten, NULL);
    }
    else
    {
        /* Rumble pack area */
    }
}