//////////////////////////////////////////////////////////////////////////
// Mapper117  Sanko Gu(Tw)                                              //
//////////////////////////////////////////////////////////////////////////
using static VirtualNes.Core.CPU;
using static VirtualNes.MMU;
using BYTE = System.Byte;


namespace VirtualNes.Core
{
    public class Mapper117 : Mapper
    {
        BYTE irq_enable;
        BYTE irq_counter;
        public Mapper117(NES parent) : base(parent)
        {
        }

        public override void Reset()

        {
            SetPROM_32K_Bank(0, 1, PROM_8K_SIZE - 2, PROM_8K_SIZE - 1);
            if (VROM_1K_SIZE != 0)
            {
                SetVROM_8K_Bank(0);
            }
        }

        //void Mapper117::Write(WORD addr, BYTE data)
        public override void Write(ushort addr, byte data)
        {
            switch (addr)
            {
                case 0x8000:
                    SetPROM_8K_Bank(4, data);
                    break;
                case 0x8001:
                    SetPROM_8K_Bank(5, data);
                    break;
                case 0x8002:
                    SetPROM_8K_Bank(6, data);
                    break;
                case 0xA000:
                    SetVROM_1K_Bank(0, data);
                    break;
                case 0xA001:
                    SetVROM_1K_Bank(1, data);
                    break;
                case 0xA002:
                    SetVROM_1K_Bank(2, data);
                    break;
                case 0xA003:
                    SetVROM_1K_Bank(3, data);
                    break;
                case 0xA004:
                    SetVROM_1K_Bank(4, data);
                    break;
                case 0xA005:
                    SetVROM_1K_Bank(5, data);
                    break;
                case 0xA006:
                    SetVROM_1K_Bank(6, data);
                    break;
                case 0xA007:
                    SetVROM_1K_Bank(7, data);
                    break;
                case 0xC001:
                case 0xC002:
                case 0xC003:
                    irq_counter = data;
                    break;
                case 0xE000:
                    irq_enable = (byte)(data & 1);
                    //			nes.cpu.ClrIRQ( IRQ_MAPPER );
                    break;
            }
        }
        //void Mapper117::HSync(INT scanline)
        public override void HSync(int scanline)
        {
            if ((scanline >= 0 && scanline <= 239))
            {
                if (nes.ppu.IsDispON())
                {
                    if (irq_enable != 0)
                    {
                        if (irq_counter == scanline)
                        {
                            irq_counter = 0;
                            //					nes.cpu.IRQ();
                            //					nes.cpu.SetIRQ( IRQ_MAPPER );
                            nes.cpu.SetIRQ(IRQ_TRIGGER);
                        }
                    }
                }
            }
        }

        //void Mapper117::SaveState(LPBYTE p)
        public override void SaveState(byte[] p)
        {
            p[0] = irq_counter;
            p[1] = irq_enable;
        }

        //void Mapper117::LoadState(LPBYTE p)
        public override void LoadState(byte[] p)
        {
            irq_counter = p[0];
            irq_enable = p[1];
        }

        public override bool IsStateSave()
        {
            return true;
        }
    }
}