using BizHawk.Common;
using BizHawk.Emulation.Common;
using BizHawk.Emulation.Cores.Computers.Commodore64.Cartridge;
using BizHawk.Emulation.Cores.Computers.Commodore64.Cassette;
using BizHawk.Emulation.Cores.Computers.Commodore64.MOS;
using BizHawk.Emulation.Cores.Computers.Commodore64.Serial;
using BizHawk.Emulation.Cores.Computers.Commodore64.User;

namespace BizHawk.Emulation.Cores.Computers.Commodore64
{
	/// <summary>
	/// Contains the onboard chipset and glue.
	/// </summary>
	public sealed partial class Motherboard
	{
		// chips
		public readonly Chip23128 BasicRom;
		public readonly Chip23128 CharRom;
		public readonly Cia Cia0;
		public readonly Cia Cia1;
		public readonly Chip2114 ColorRam;
		public readonly Chip6510 Cpu;
		public readonly Chip23128 KernalRom;
		public readonly Chip90611401 Pla;
		public readonly Chip4864 Ram;
		public readonly Sid Sid;
		public readonly Vic Vic;

		// ports
		public readonly CartridgePort CartPort;
		public readonly CassettePort Cassette;
		public IController Controller = NullController.Instance;
		public readonly SerialPort Serial;
		public readonly TapeDrive TapeDrive;
		public readonly UserPort User;

		// devices
		public readonly Drive1541 DiskDrive;

		// state
		public bool InputRead;
		public bool Irq;
		public bool Nmi;

		private readonly C64 _c64;

		public Motherboard(C64 c64, C64.VicType initRegion, C64.BorderType borderType, C64.SidType sidType, C64.TapeDriveType tapeDriveType, C64.DiskDriveType diskDriveType)
		{
			// note: roms need to be added on their own externally
			_c64 = c64;
			int clockNum, clockDen;
			switch (initRegion)
			{
				case C64.VicType.Pal:
					clockNum = 17734475;
					clockDen = 18;
					break;
				case C64.VicType.Ntsc:
					clockNum = 14318181;
					clockDen = 14;
					break;
				case C64.VicType.NtscOld:
					clockNum = 11250000;
					clockDen = 11;
					break;
				case C64.VicType.Drean:
					clockNum = 14328225;
					clockDen = 14;
					break;
				default:
					throw new System.Exception();
			}
			CartPort = new CartridgePort();
			Cassette = new CassettePort();
			ColorRam = new Chip2114();
			Cpu = new Chip6510();
			Pla = new Chip90611401();
			Ram = new Chip4864();
			Serial = new SerialPort();

			switch (sidType)
			{
				case C64.SidType.OldR2:
					Sid = Chip6581R2.Create(44100, clockNum, clockDen);
					break;
				case C64.SidType.OldR3:
					Sid = Chip6581R3.Create(44100, clockNum, clockDen);
					break;
				case C64.SidType.OldR4AR:
					Sid = Chip6581R4AR.Create(44100, clockNum, clockDen);
					break;
				case C64.SidType.NewR5:
					Sid = Chip8580R5.Create(44100, clockNum, clockDen);
					break;
			}

			switch (initRegion)
			{
				case C64.VicType.Ntsc:
					Vic = Chip6567R8.Create(borderType);
					Cia0 = Chip6526.CreateCia0(C64.CiaType.Ntsc, Input_ReadKeyboard, Input_ReadJoysticks);
					Cia1 = Chip6526.CreateCia1(C64.CiaType.Ntsc, Cia1_ReadPortA, () => 0xFF);
					break;
				case C64.VicType.Pal:
					Vic = Chip6569.Create(borderType);
					Cia0 = Chip6526.CreateCia0(C64.CiaType.Pal, Input_ReadKeyboard, Input_ReadJoysticks);
					Cia1 = Chip6526.CreateCia1(C64.CiaType.Pal, Cia1_ReadPortA, () => 0xFF);
					break;
				case C64.VicType.NtscOld:
					Vic = Chip6567R56A.Create(borderType);
					Cia0 = Chip6526.CreateCia0(C64.CiaType.NtscRevA, Input_ReadKeyboard, Input_ReadJoysticks);
					Cia1 = Chip6526.CreateCia1(C64.CiaType.NtscRevA, Cia1_ReadPortA, () => 0xFF);
					break;
				case C64.VicType.Drean:
					Vic = Chip6572.Create(borderType);
					Cia0 = Chip6526.CreateCia0(C64.CiaType.Pal, Input_ReadKeyboard, Input_ReadJoysticks);
					Cia1 = Chip6526.CreateCia1(C64.CiaType.Pal, Cia1_ReadPortA, () => 0xFF);
					break;
			}
			User = new UserPort();

			ClockNumerator = clockNum;
			ClockDenominator = clockDen;

			// Initialize disk drive
			switch (diskDriveType)
			{
				case C64.DiskDriveType.Commodore1541:
				case C64.DiskDriveType.Commodore1541II:
					DiskDrive = new Drive1541(ClockNumerator, ClockDenominator);
					Serial.Connect(DiskDrive);
					break;
			}

			// Initialize tape drive
			switch (tapeDriveType)
			{
				case C64.TapeDriveType.Commodore1530:
					TapeDrive = new TapeDrive();
					Cassette.Connect(TapeDrive);
					break;
			}

			BasicRom = new Chip23128();
			CharRom = new Chip23128();
			KernalRom = new Chip23128();
			
			if (Cpu != null)
				Cpu.DebuggerStep = Execute;
			if (DiskDrive != null)
				DiskDrive.DebuggerStep = Execute;
		}

		public int ClockNumerator { get; }
		public int ClockDenominator { get; }

		// -----------------------------------------
		public void Execute()
		{
			_vicBank = (0x3 - ((Cia1.PrA | ~Cia1.DdrA) & 0x3)) << 14;

			Vic.ExecutePhase1();
			CartPort.ExecutePhase();
			Cassette.ExecutePhase();
			Serial.ExecutePhase();
			Sid.ExecutePhase();
			Cia0.ExecutePhase();
			Cia1.ExecutePhase();
			Cpu.ExecutePhase();
			Vic.ExecutePhase2();
		}

		public void Flush()
		{
			Sid.Flush(false);
		}

		// -----------------------------------------
		public void HardReset()
		{
			_lastReadVicAddress = 0x3FFF;
			_lastReadVicData = 0xFF;
			InputRead = false;

			Cia0.HardReset();
			Cia1.HardReset();
			ColorRam.HardReset();
			Ram.HardReset();
			Serial.HardReset();
			Sid.HardReset();
			Vic.HardReset();
			User.HardReset();
			Cassette.HardReset();
			Serial.HardReset();
			Cpu.HardReset();
			CartPort.HardReset();
		}

		public void SoftReset()
		{
			// equivalent to a hard reset EXCEPT cpu, color ram, memory
			_lastReadVicAddress = 0x3FFF;
			_lastReadVicData = 0xFF;
			InputRead = false;

			Cia0.HardReset();
			Cia1.HardReset();
			Serial.HardReset();
			Sid.HardReset();
			Vic.HardReset();
			User.HardReset();
			Cassette.HardReset();
			Serial.HardReset();
			Cpu.SoftReset();
			CartPort.HardReset();
		}

		public void Init()
		{
			CartPort.ReadOpenBus = ReadOpenBus;

			Cassette.ReadDataOutput = CassPort_ReadDataOutput;
			Cassette.ReadMotor = CassPort_ReadMotor;

			Cia0.ReadFlag = Cassette.ReadDataInputBuffer;

			Cpu.PeekMemory = Pla.Peek;
			Cpu.PokeMemory = Pla.Poke;
			Cpu.ReadAec = Vic.ReadAec;
			Cpu.ReadIrq = Glue_ReadIRQ;
			Cpu.ReadNmi = Glue_ReadNMI;
			Cpu.ReadPort = Cpu_ReadPort;
			Cpu.ReadRdy = Vic.ReadBa;
			Cpu.ReadMemory = Pla.Read;
			Cpu.WriteMemory = Pla.Write;
			Cpu.WriteMemoryPort = Cpu_WriteMemoryPort;
			Cpu.ReadBus = ReadOpenBus;

			Pla.PeekBasicRom = BasicRom.Peek;
			Pla.PeekCartridgeHi = CartPort.PeekHiRom;
			Pla.PeekCartridgeLo = CartPort.PeekLoRom;
			Pla.PeekCharRom = CharRom.Peek;
			Pla.PeekCia0 = Cia0.Peek;
			Pla.PeekCia1 = Cia1.Peek;
			Pla.PeekColorRam = ColorRam.Peek;
			Pla.PeekExpansionHi = CartPort.PeekHiExp;
			Pla.PeekExpansionLo = CartPort.PeekLoExp;
			Pla.PeekKernalRom = KernalRom.Peek;
			Pla.PeekMemory = Ram.Peek;
			Pla.PeekSid = Sid.Peek;
			Pla.PeekVic = Vic.Peek;
			Pla.PokeCartridgeHi = CartPort.PokeHiRom;
			Pla.PokeCartridgeLo = CartPort.PokeLoRom;
			Pla.PokeCia0 = Cia0.Poke;
			Pla.PokeCia1 = Cia1.Poke;
			Pla.PokeColorRam = ColorRam.Poke;
			Pla.PokeExpansionHi = CartPort.PokeHiExp;
			Pla.PokeExpansionLo = CartPort.PokeLoExp;
			Pla.PokeMemory = Ram.Poke;
			Pla.PokeSid = Sid.Poke;
			Pla.PokeVic = Vic.Poke;
			Pla.ReadBasicRom = BasicRom.Read;
			Pla.ReadCartridgeHi = CartPort.ReadHiRom;
			Pla.ReadCartridgeLo = CartPort.ReadLoRom;
			Pla.ReadCharen = Pla_ReadCharen;
			Pla.ReadCharRom = CharRom.Read;
			Pla.ReadCia0 = Pla_ReadCia0;
			Pla.ReadCia1 = Cia1.Read;
			Pla.ReadColorRam = Pla_ReadColorRam;
			Pla.ReadExpansionHi = Pla_ReadExpansion1;
			Pla.ReadExpansionLo = Pla_ReadExpansion0;
			Pla.ReadExRom = CartPort.ReadExRom;
			Pla.ReadGame = CartPort.ReadGame;
			Pla.ReadHiRam = Pla_ReadHiRam;
			Pla.ReadKernalRom = KernalRom.Read;
			Pla.ReadLoRam = Pla_ReadLoRam;
			Pla.ReadMemory = Ram.Read;
			Pla.ReadSid = Sid.Read;
			Pla.ReadVic = Vic.Read;
			Pla.WriteCartridgeHi = CartPort.WriteHiRom;
			Pla.WriteCartridgeLo = CartPort.WriteLoRom;
			Pla.WriteCia0 = Cia0.Write;
			Pla.WriteCia1 = Cia1.Write;
			Pla.WriteColorRam = ColorRam.Write;
			Pla.WriteExpansionHi = CartPort.WriteHiExp;
			Pla.WriteExpansionLo = CartPort.WriteLoExp;
			Pla.WriteMemory = Ram.Write;
			Pla.WriteSid = Sid.Write;
			Pla.WriteVic = Vic.Write;

			Serial.ReadMasterAtn = SerPort_ReadAtnOut;
			Serial.ReadMasterClk = SerPort_ReadClockOut;
			Serial.ReadMasterData = SerPort_ReadDataOut;

			Sid.ReadPotX = Sid_ReadPotX;
			Sid.ReadPotY = Sid_ReadPotY;

			Vic.ReadMemory = Vic_ReadMemory;
			Vic.ReadColorRam = ColorRam.Read;
		}

		public void SyncState(Serializer ser)
		{
			ser.BeginSection(nameof(Cia0));
			Cia0.SyncState(ser);
			ser.EndSection();

			ser.BeginSection(nameof(Cia1));
			Cia1.SyncState(ser);
			ser.EndSection();

			ser.BeginSection(nameof(ColorRam));
			ColorRam.SyncState(ser);
			ser.EndSection();

			ser.BeginSection(nameof(Cpu));
			Cpu.SyncState(ser);
			ser.EndSection();

			ser.BeginSection(nameof(Pla));
			Pla.SyncState(ser);
			ser.EndSection();

			ser.BeginSection(nameof(Ram));
			Ram.SyncState(ser);
			ser.EndSection();

			ser.BeginSection(nameof(Sid));
			Sid.SyncState(ser);
			ser.EndSection();

			ser.BeginSection(nameof(Vic));
			Vic.SyncState(ser);
			ser.EndSection();

			if (CartPort.IsConnected)
			{
				ser.BeginSection(nameof(CartPort));
				CartPort.SyncState(ser);
				ser.EndSection();
			}

			ser.BeginSection(nameof(Cassette));
			Cassette.SyncState(ser);
			ser.EndSection();

			ser.BeginSection(nameof(Serial));
			Serial.SyncState(ser);
			ser.EndSection();

			if (TapeDrive != null) // TODO: a tape object is already in a nested class, is it the same reference? do we need this?
			{
				ser.BeginSection(nameof(TapeDrive));
				TapeDrive.SyncState(ser);
				ser.EndSection();
			}

			ser.BeginSection(nameof(User));
			User.SyncState(ser);
			ser.EndSection();

			if (DiskDrive != null) // TODO: a disk object is already in a nested class, is it the same reference? do we need this?
			{
				ser.BeginSection(nameof(DiskDrive));
				DiskDrive.SyncState(ser);
				ser.EndSection();
			}

			ser.Sync(nameof(InputRead), ref InputRead);
			ser.Sync(nameof(Irq), ref Irq);
			ser.Sync(nameof(Nmi), ref Nmi);

			ser.Sync(nameof(_lastReadVicAddress), ref _lastReadVicAddress);
			ser.Sync(nameof(_lastReadVicData), ref _lastReadVicData);
			ser.Sync(nameof(_vicBank), ref _vicBank);

			ser.Sync(nameof(_joystickPressed), ref _joystickPressed, useNull: false);
			ser.Sync(nameof(_keyboardPressed), ref _keyboardPressed, useNull: false);
			ser.Sync(nameof(_restorePressed), ref _restorePressed);
		}
	}
}