#pragma once
#include "BaseMapper.h"
#include "CPU.h"

class FrontFareast : public BaseMapper
{
private:
	uint16_t _irqCounter;
	bool _irqEnabled;
	bool _ffeAltMode;

protected:
	uint16_t GetPRGPageSize() override { return 0x2000; }
	uint16_t GetCHRPageSize() override { return 0x400; }
	uint32_t GetChrRamSize() override { return 0x8000; }
	uint16_t RegisterStartAddress() override { return 0x42FE; }
	uint16_t RegisterEndAddress() override { return 0x4517; }

	void InitMapper() override
	{
		_irqCounter = 0;
		_irqEnabled = false;
		_ffeAltMode = true;

		switch(_mapperID) {
			case 6:
				AddRegisterRange(0x8000, 0xFFFF, MemoryOperation::Write);
				SelectPrgPage2x(0, 0);
				SelectPrgPage2x(1, 14);
				break;

			case 8:
				AddRegisterRange(0x8000, 0xFFFF, MemoryOperation::Write);
				SelectPrgPage4x(0, 0);
				break;

			case 17:
				SelectPrgPage4x(0, -4);
				break;
		}
	}

	void StreamState(bool saving) override
	{
		BaseMapper::StreamState(saving);
		Stream(_irqCounter, _irqEnabled, _ffeAltMode);
	}

	void ProcessCpuClock() override
	{
		if(_irqEnabled) {
			_irqCounter++;
			if(_irqCounter == 0) {
				CPU::SetIRQSource(IRQSource::External);
				_irqEnabled = false;
			}
		}
	}

	void WriteRegister(uint16_t addr, uint8_t value) override
	{
		switch(addr) {
			case 0x42FE:
				_ffeAltMode = (value & 0x80) == 0x00;
				switch((value >> 4) & 0x01) {
					case 0: SetMirroringType(MirroringType::ScreenAOnly); break;
					case 1: SetMirroringType(MirroringType::ScreenBOnly); break;
				}
				break;

			case 0x42FF:
				switch((value >> 4) & 0x01) {
					case 0: SetMirroringType(MirroringType::Vertical); break;
					case 1: SetMirroringType(MirroringType::Horizontal); break;
				}
				break;

			case 0x4501: 
				_irqEnabled = false;
				CPU::ClearIRQSource(IRQSource::External); 
				break;

			case 0x4502: 
				_irqCounter = (_irqCounter & 0xFF00) | value;
				CPU::ClearIRQSource(IRQSource::External);
				break;

			case 0x4503: 
				_irqCounter = (_irqCounter & 0x00FF) | (value << 8);
				_irqEnabled = true;
				CPU::ClearIRQSource(IRQSource::External);
				break;

			default:
				if(_mapperID == 6) {
					if(addr >= 0x8000) {
						if(HasChrRam() || _ffeAltMode) {
							SelectPrgPage2x(0, (value & 0xFC) >> 1);
							value &= 0x03;
						}
						SelectChrPage8x(0, value << 3);
					}
				} else if(_mapperID == 8) {
					if(addr >= 0x8000) {
						SelectPrgPage2x(0, (value & 0xF8) >> 2);
						SelectChrPage8x(0, (value & 0x07) << 3);
					}
				} else {
					switch(addr) {
						case 0x4504: case 0x4505: case 0x4506: case 0x4507:
							SelectPRGPage(addr - 0x4504, value);
							break;

						case 0x4510: case 0x4511: case 0x4512: case 0x4513: case 0x4514: case 0x4515: case 0x4516: case 0x4517:
							SelectCHRPage(addr - 0x4510, value);
							break;
					}
				}
		}
	}
};