//////////////////////////////////////////////////////////////////////////
// Mapper045  1000000-in-1                                              //
//////////////////////////////////////////////////////////////////////////
using System;
using static VirtualNes.Core.CPU;
using static VirtualNes.MMU;
using BYTE = System.Byte;
using INT = System.Int32;


namespace VirtualNes.Core
{
    public class Mapper045 : Mapper
    {
        BYTE[] reg = new byte[8];
        BYTE patch;
        BYTE prg0, prg1, prg2, prg3;
        BYTE chr0, chr1, chr2, chr3, chr4, chr5, chr6, chr7;
        BYTE[] p = new byte[4];
        INT[] c = new int[8];
        BYTE irq_enable;
        BYTE irq_counter;
        BYTE irq_latch;
        BYTE irq_latched;
        BYTE irq_reset;
        public Mapper045(NES parent) : base(parent)
        {
        }


        public override void Reset()
        {
            patch = 0;
            for (INT i = 0; i < 8; i++)
            {
                reg[i] = 0;
            }

            prg0 = 0;
            prg1 = 1;
            prg2 = (byte)(PROM_8K_SIZE - 2);
            prg3 = (byte)(PROM_8K_SIZE - 1);

            uint crc = nes.rom.GetPROM_CRC();
            if (crc == 0x58bcacf6       // Kunio 8-in-1 (Pirate Cart)
             || crc == 0x9103cfd6       // HIK 7-in-1 (Pirate Cart)
             || crc == 0xc082e6d3)
            {   // Super 8-in-1 (Pirate Cart)
                patch = 1;
                prg2 = 62;
                prg3 = 63;
            }
            if (crc == 0xe0dd259d)
            {   // Super 3-in-1 (Pirate Cart)
                patch = 2;
            }
            SetPROM_32K_Bank(prg0, prg1, prg2, prg3);
            p[0] = prg0;
            p[1] = prg1;
            p[2] = prg2;
            p[3] = prg3;

            SetVROM_8K_Bank(0);

            //	chr0 = c[0] = 0;
            //	chr1 = c[1] = 0
            //	chr2 = c[2] = 0;
            //	chr3 = c[3] = 0;
            //	chr4 = c[4] = 0;
            //	chr5 = c[5] = 0;
            //	chr6 = c[6] = 0;
            //	chr7 = c[7] = 0;

            c[0] = chr0 = 0;
            c[1] = chr1 = 1;
            c[2] = chr2 = 2;
            c[3] = chr3 = 3;
            c[4] = chr4 = 4;
            c[5] = chr5 = 5;
            c[6] = chr6 = 6;
            c[7] = chr7 = 7;

            irq_enable = 0;
            irq_counter = 0;
            irq_latch = 0;
            irq_latched = 0;
            irq_reset = 0;
        }

        //void Mapper045::WriteLow(WORD addr, BYTE data)
        public override void WriteLow(ushort addr, byte data)
        {
            //	if( addr == 0x6000 ) {
            //	if( addr == 0x6000 && !(reg[3]&0x40) ) {
            if ((reg[3] & 0x40) == 0)
            {
                reg[reg[5]] = data;
                reg[5] = (byte)((reg[5] + 1) & 0x03);

                SetBank_CPU_4(prg0);
                SetBank_CPU_5(prg1);
                SetBank_CPU_6(prg2);
                SetBank_CPU_7(prg3);
                SetBank_PPU();
            }
        }

        //void Mapper045::Write(WORD addr, BYTE data)
        public override void Write(ushort addr, byte data)
        {
            switch (addr & 0xE001)
            {
                case 0x8000:
                    if ((data & 0x40) != (reg[6] & 0x40))
                    {
                        BYTE swp;
                        swp = prg0; prg0 = prg2; prg2 = swp;
                        swp = p[0]; p[0] = p[2]; p[2] = swp;
                        SetBank_CPU_4(p[0]);
                        SetBank_CPU_5(p[1]);
                    }
                    if (VROM_1K_SIZE != 0)
                    {
                        if ((data & 0x80) != (reg[6] & 0x80))
                        {
                            INT swp;
                            swp = chr4; chr4 = chr0; chr0 = (byte)swp;
                            swp = chr5; chr5 = chr1; chr1 = (byte)swp;
                            swp = chr6; chr6 = chr2; chr2 = (byte)swp;
                            swp = chr7; chr7 = chr3; chr3 = (byte)swp;
                            swp = c[4]; c[4] = c[0]; c[0] = swp;
                            swp = c[5]; c[5] = c[1]; c[1] = swp;
                            swp = c[6]; c[6] = c[2]; c[2] = swp;
                            swp = c[7]; c[7] = c[3]; c[3] = swp;
                            SetVROM_8K_Bank(c[0], c[1], c[2], c[3], c[4], c[5], c[6], c[7]);
                        }
                    }
                    reg[6] = data;
                    break;
                case 0x8001:
                    switch (reg[6] & 0x07)
                    {
                        case 0x00:
                            chr0 = (byte)((data & 0xFE) + 0);
                            chr1 = (byte)((data & 0xFE) + 1);
                            SetBank_PPU();
                            break;
                        case 0x01:
                            chr2 = (byte)((data & 0xFE) + 0);
                            chr3 = (byte)((data & 0xFE) + 1);
                            SetBank_PPU();
                            break;
                        case 0x02:
                            chr4 = data;
                            SetBank_PPU();
                            break;
                        case 0x03:
                            chr5 = data;
                            SetBank_PPU();
                            break;
                        case 0x04:
                            chr6 = data;
                            SetBank_PPU();
                            break;
                        case 0x05:
                            chr7 = data;
                            SetBank_PPU();
                            break;
                        case 0x06:
                            if ((reg[6] & 0x40) != 0)
                            {
                                prg2 = (byte)(data & 0x3F);
                                SetBank_CPU_6(data);
                            }
                            else
                            {
                                prg0 = (byte)(data & 0x3F);
                                SetBank_CPU_4(data);
                            }
                            break;
                        case 0x07:
                            prg1 = (byte)(data & 0x3F);
                            SetBank_CPU_5(data);
                            break;
                    }
                    break;
                case 0xA000:
                    if ((data & 0x01) != 0) SetVRAM_Mirror(VRAM_HMIRROR);
                    else SetVRAM_Mirror(VRAM_VMIRROR);
                    break;
                case 0xC000:
                    if (patch == 2)
                    {
                        if (data == 0x29 || data == 0x70)
                            data = 0x07;
                    }
                    irq_latch = data;
                    irq_latched = 1;
                    if (irq_reset != 0)
                    {
                        irq_counter = data;
                        irq_latched = 0;
                    }
                    //			irq_counter = data;
                    break;
                case 0xC001:
                    //			irq_latch = data;
                    irq_counter = irq_latch;
                    break;
                case 0xE000:
                    irq_enable = 0;
                    irq_reset = 1;
                    nes.cpu.ClrIRQ(IRQ_MAPPER);
                    break;
                case 0xE001:
                    irq_enable = 1;
                    if (irq_latched != 0)
                    {
                        irq_counter = irq_latch;
                    }
                    break;
            }
        }

        //void Mapper045::HSync(INT scanline)
        public override void HSync(int scanline)
        {
            irq_reset = 0;
            if ((scanline >= 0 && scanline <= 239) && nes.ppu.IsDispON())
            {
                if (irq_counter != 0)
                {
                    irq_counter--;
                    if (irq_counter == 0)
                    {
                        if (irq_enable != 0)
                        {
                            nes.cpu.SetIRQ(IRQ_MAPPER);
                        }
                    }
                }
            }
        }

        void SetBank_CPU_4(INT data)
        {
            data &= (reg[3] & 0x3F) ^ 0xFF;
            data &= 0x3F;
            data |= reg[1];
            SetPROM_8K_Bank(4, data);
            p[0] = (byte)data;
        }

        void SetBank_CPU_5(INT data)
        {
            data &= (reg[3] & 0x3F) ^ 0xFF;
            data &= 0x3F;
            data |= reg[1];
            SetPROM_8K_Bank(5, data);
            p[1] = (byte)data;
        }

        void SetBank_CPU_6(INT data)
        {
            data &= (reg[3] & 0x3F) ^ 0xFF;
            data &= 0x3F;
            data |= reg[1];
            SetPROM_8K_Bank(6, data);
            p[2] = (byte)data;
        }

        void SetBank_CPU_7(INT data)
        {
            data &= (reg[3] & 0x3F) ^ 0xFF;
            data &= 0x3F;
            data |= reg[1];
            SetPROM_8K_Bank(7, data);
            p[3] = (byte)data;
        }

        void SetBank_PPU()
        {
            BYTE[] table = new byte[] {
        0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
        0x01,0x03,0x07,0x0F,0x1F,0x3F,0x7F,0xFF
    };

            c[0] = chr0;
            c[1] = chr1;
            c[2] = chr2;
            c[3] = chr3;
            c[4] = chr4;
            c[5] = chr5;
            c[6] = chr6;
            c[7] = chr7;

            for (INT i = 0; i < 8; i++)
            {
                c[i] &= table[reg[2] & 0x0F];
                c[i] |= reg[0] & ((patch != 1) ? 0xFF : 0xC0);
                c[i] += (reg[2] & ((patch != 1) ? 0x10 : 0x30)) << 4;
            }

            if ((reg[6] & 0x80) != 0)
            {
                SetVROM_8K_Bank(c[4], c[5], c[6], c[7], c[0], c[1], c[2], c[3]);
            }
            else
            {
                SetVROM_8K_Bank(c[0], c[1], c[2], c[3], c[4], c[5], c[6], c[7]);
            }
        }

        //void Mapper045::SaveState(LPBYTE ps)
        public override void SaveState(byte[] ps)
        {
            int i;
            for (i = 0; i < 8; i++)
            {
                ps[i] = reg[i];
            }
            for (i = 0; i < 4; i++)
            {
                ps[i + 8] = p[i];
            }
            for (i = 0; i < 8; i++)
            {
                //*(INT*)&ps[i * 4 + 64] = c[i];
                BitConverter.GetBytes(c[i]).CopyTo(ps, i * 4 + 64);
            }
            ps[20] = prg0;
            ps[21] = prg1;
            ps[22] = prg2;
            ps[23] = prg3;
            ps[24] = chr0;
            ps[25] = chr1;
            ps[26] = chr2;
            ps[27] = chr3;
            ps[28] = chr4;
            ps[29] = chr5;
            ps[30] = chr6;
            ps[31] = chr7;
            ps[32] = irq_enable;
            ps[33] = irq_counter;
            ps[34] = irq_latch;
        }

        //void Mapper045::LoadState(LPBYTE ps)
        public override void LoadState(byte[] ps)
        {
            int i;
            for (i = 0; i < 8; i++)
            {
                reg[i] = ps[i];
            }
            for (i = 0; i < 4; i++)
            {
                p[i] = ps[i + 8];
            }
            for (i = 0; i < 8; i++)
            {
                //c[i] = *(INT*)&ps[i * 4 + 64];
                c[i] = BitConverter.ToInt32(ps, i * 4 + 64);
            }
            prg0 = ps[20];
            prg1 = ps[21];
            prg2 = ps[22];
            prg3 = ps[23];
            chr0 = ps[24];
            chr1 = ps[25];
            chr2 = ps[26];
            chr3 = ps[27];
            chr4 = ps[28];
            chr5 = ps[29];
            chr6 = ps[30];
            chr7 = ps[31];
            irq_enable = ps[32];
            irq_counter = ps[33];
            irq_latch = ps[34];
        }



        public override bool IsStateSave()
        {
            return true;
        }

    }
}