//////////////////////////////////////////////////////////////////////////
// Mapper006  FFE F4xxx                                                 //
//////////////////////////////////////////////////////////////////////////
using static VirtualNes.MMU;
using static VirtualNes.Core.CPU;
using INT = System.Int32;
using BYTE = System.Byte;
//using Codice.CM.Client.Differences;

namespace VirtualNes.Core
{
	public class Mapper006 : Mapper
	{
		BYTE irq_enable;
		INT irq_counter;
		public Mapper006(NES parent) : base(parent) { }

		public override void Reset()
		{
			SetPROM_32K_Bank(0, 1, 14, 15);

			if (VROM_1K_SIZE != 0)
			{
				SetVROM_8K_Bank(0);
			}
			else
			{
				SetCRAM_8K_Bank(0);
			}

			irq_enable = 0;
			irq_counter = 0;
		}

		//void Mapper006::WriteLow(WORD addr, BYTE data)
		public override void WriteLow(ushort addr, byte data)
		{
			switch (addr)
			{
				case 0x42FE:
					if ((data & 0x10) != 0) SetVRAM_Mirror(VRAM_MIRROR4H);
					else SetVRAM_Mirror(VRAM_MIRROR4L);
					break;
				case 0x42FF:
					if ((data & 0x10) != 0) SetVRAM_Mirror(VRAM_HMIRROR);
					else SetVRAM_Mirror(VRAM_VMIRROR);
					break;

				case 0x4501:
					irq_enable = 0;

					nes.cpu.ClrIRQ(IRQ_MAPPER);
					break;
				case 0x4502:
					irq_counter = (irq_counter & 0xFF00) | data;
					break;
				case 0x4503:
					irq_counter = (irq_counter & 0x00FF) | ((INT)data << 8);
					irq_enable = 0xFF;

					nes.cpu.ClrIRQ(IRQ_MAPPER);
					break;
				default:
					base.WriteLow(addr, data);
					break;
			}
		}

		//void Mapper006::Write(WORD addr, BYTE data)
		public override void Write(ushort addr, byte data)
		{
			SetPROM_16K_Bank(4, (data & 0x3C) >> 2);
			SetCRAM_8K_Bank(data & 0x03);
		}

		//void Mapper006::HSync(INT scanline)
		public override void HSync(int scanline)
		{
			if (irq_enable != 0)
			{
				irq_counter += 133;
				if (irq_counter >= 0xFFFF)
				{
					//			nes.cpu.IRQ();
					irq_counter = 0;

					nes.cpu.SetIRQ(IRQ_MAPPER);
				}
			}
		}

		//void Mapper006::SaveState(LPBYTE p)
		public override void SaveState(byte[] p)
		{
			//p[0] = irq_enable;
			//*(INT*)&p[1] = irq_counter;
		}

		//void Mapper006::LoadState(LPBYTE p)
		public override void LoadState(byte[] p)
		{
			//irq_enable = p[0];
			//irq_counter = *(INT*)&p[1];
		}


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