/****************************************************************************
*                                                                           *
* 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>

uint8_t Mempaks[4][128 * 256]; /* [CONTROLLERS][PAGES][BYTES_PER_PAGE] */
CPath MempakNames[4];

void Mempak::Load()
{
    stdstr MempakName;

    for (int i = 0; i < 3; i++)
    {
        MempakName.Format("%s_Cont_%d", g_Settings->LoadStringVal(Game_GameName).c_str(), i + 1);

        MempakNames[i].SetDriveDirectory(g_Settings->LoadStringVal(Directory_NativeSave).c_str());
        MempakNames[i].SetName(MempakName.c_str());
        MempakNames[i].SetExtension("mpk");

        if (!MempakNames[i].DirectoryExists())
        {
            MempakNames[i].DirectoryCreate();
        }

        if (MempakNames[i].Exists())
        {
            FILE *mempak = fopen(MempakNames[i], "rb");
            fread(Mempaks[i], 1, 0x8000, mempak);
            fclose(mempak);
        }
        else
        {
            Mempak::Format(i);
        }
    }
}

void Mempak::Format(int32_t Control)
{
    static const 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[0], sizeof(Initialize));

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

uint8_t Mempak::CalculateCrc(uint8_t * DataToCrc)
{
    uint32_t Count;
    uint32_t XorTap;

    int32_t 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(int32_t Control, uint32_t address, uint8_t * data)
{
    if (address < 0x8000)
    {
        memcpy(data, &Mempaks[Control][address], 0x20);
    }
    else
    {
        memset(data, 0x00, 0x20);
        /* Rumble pack area */
    }
}

void Mempak::WriteTo(int32_t Control, uint32_t address, uint8_t * data)
{
    if (address < 0x8000)
    {
        memcpy(&Mempaks[Control][address], data, 0x20);

        FILE* mempak = fopen(MempakNames[Control], "wb");
        fwrite(Mempaks[Control], 1, 0x8000, mempak);
        fclose(mempak);
    }
    else
    {
        /* Rumble pack area */
    }
}