Mesen/Core/SnesMouse.h

#pragma once
#include "stdafx.h"
#include "BaseControlDevice.h"
#include "IKeyManager.h"
#include "KeyManager.h"

class SnesMouse : public BaseControlDevice
{
private:
	uint32_t _stateBuffer = 0;
	uint8_t _sensitivity = 0;

protected:
	bool HasCoordinates() override { return true; }

	enum Buttons { Left = 0, Right };

	void StreamState(bool saving) override
	{
		BaseControlDevice::StreamState(saving);
		Stream(_stateBuffer, _sensitivity);
	}

	string GetKeyNames() override
	{
		return "LR";
	}

	void InternalSetStateFromInput() override
	{
		SetPressedState(Buttons::Left, KeyManager::IsMouseButtonPressed(MouseButton::LeftButton));
		SetPressedState(Buttons::Right, KeyManager::IsMouseButtonPressed(MouseButton::RightButton));
		SetMovement(KeyManager::GetMouseMovement());
	}

public:
	SnesMouse(uint8_t port) : BaseControlDevice(port)
	{
	}

	void WriteRAM(uint16_t addr, uint8_t value) override
	{
		StrobeProcessWrite(value);
	}

	uint8_t ReadRAM(uint16_t addr) override
	{
		uint8_t output = 0;
		if((addr == 0x4016 && (_port & 0x01) == 0) || (addr == 0x4017 && (_port & 0x01) == 1)) {
			if(_strobe) {
				_sensitivity = (_sensitivity + 1) & 0x03;
			}

			output = (_stateBuffer & 0x80000000) >> 31;
			if(_port >= 2) {
				output <<= 1;
			}
			_stateBuffer <<= 1;
			StrobeProcessRead();
		}
		return output;
	}

	void RefreshStateBuffer() override
	{
		MouseMovement mov = GetMovement();
		int32_t dx = mov.dx * (1 + _sensitivity);
		int32_t dy = mov.dy * (1 + _sensitivity);

		uint32_t upFlag = dy < 0 ? 0x80 : 0;
		uint32_t leftFlag = dx < 0 ? 0x80 : 0;

		dx = std::min(std::abs(dx), 127);
		dy = std::min(std::abs(dy), 127);

		uint8_t byte1 = 0;
		uint8_t byte2 = 0x01 | ((_sensitivity & 0x03) << 4) | (IsPressed(SnesMouse::Buttons::Left) ? 0x40 : 0) | (IsPressed(SnesMouse::Buttons::Right) ? 0x80 : 0);
		uint8_t byte3 = dy | upFlag;
		uint8_t byte4 = dx | leftFlag;

		_stateBuffer = (byte1 << 24) | (byte2 << 16) | (byte3 << 8) | byte4;
	}
};