/*
	This file is part of Fennix Drivers.

	Fennix Drivers is free software: you can redistribute it and/or
	modify it under the terms of the GNU General Public License as
	published by the Free Software Foundation, either version 3 of
	the License, or (at your option) any later version.

	Fennix Drivers is distributed in the hope that it will be useful,
	but WITHOUT ANY WARRANTY; without even the implied warranty of
	MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	GNU General Public License for more details.

	You should have received a copy of the GNU General Public License
	along with Fennix Drivers. If not, see <https://www.gnu.org/licenses/>.
*/

#include "aip.h"

#include <errno.h>
#include <base.h>
#include <fs.h>
#include <input.h>

dev_t MouseDevID = -1;
bool PacketReady = false;
bool FourPackets = false;
bool MouseButton45 = false;
uint8_t Cycle = 0;
PS2_MOUSE_PACKET Packet = {0};

InputReport mir = {0};
void PS2MouseInterruptHandler(TrapFrame *)
{
	uint8_t data = PS2ReadData();
	if (data == PS2_MOUSE_RESP_ACK ||
		data == PS2_MOUSE_RESP_RESEND)
		return;

	if (!PacketReady)
	{
		switch (Cycle)
		{
		case 0:
		{
			if ((data & 0b00001000 /* Always 1 */) == 0)
				return;

			Packet.Base.Raw = data;
			Cycle++;
			break;
		}
		case 1:
		{
			Packet.XMovement = data;
			Cycle++;
			break;
		}
		case 2:
		{
			Packet.YMovement = data;
			if (FourPackets)
				Cycle++;
			else
			{
				Cycle = 0;
				PacketReady = true;
			}
			break;
		}
		case 3:
		{
			Packet.ZMovement.Raw = data;
			Cycle = 0;
			PacketReady = true;
			break;
		}
		default:
			break;
		}
		return;
	}

/* https://stackoverflow.com/a/3208376/9352057 */
#define BYTE_TO_BINARY_PATTERN "%c%c%c%c%c%c%c%c"
#define BYTE_TO_BINARY(byte)         \
	((byte) & 0x80 ? '1' : '0'),     \
		((byte) & 0x40 ? '1' : '0'), \
		((byte) & 0x20 ? '1' : '0'), \
		((byte) & 0x10 ? '1' : '0'), \
		((byte) & 0x08 ? '1' : '0'), \
		((byte) & 0x04 ? '1' : '0'), \
		((byte) & 0x02 ? '1' : '0'), \
		((byte) & 0x01 ? '1' : '0')

	DebugLog("PS/2 Mouse Packet: [" BYTE_TO_BINARY_PATTERN ":" BYTE_TO_BINARY_PATTERN ":" BYTE_TO_BINARY_PATTERN ":" BYTE_TO_BINARY_PATTERN "] LB:%d RB:%d MB:%d A1:%d XS:%d YS:%d XO:%d YO:%d | X:%03d Y:%03d | Z:%d B4:%d B5:%d A0:%d A0:%d",
			 BYTE_TO_BINARY(Packet.Base.Raw),
			 BYTE_TO_BINARY(Packet.XMovement),
			 BYTE_TO_BINARY(Packet.YMovement),
			 BYTE_TO_BINARY(Packet.ZMovement.Raw),
			 Packet.Base.LeftButton, Packet.Base.RightButton, Packet.Base.MiddleButton,
			 Packet.Base.Always1,
			 Packet.Base.XSign, Packet.Base.YSign,
			 Packet.Base.XOverflow, Packet.Base.YOverflow,
			 Packet.XMovement, Packet.YMovement,
			 Packet.ZMovement.Z, Packet.ZMovement.Button4, Packet.ZMovement.Button5,
			 Packet.ZMovement.Always0, Packet.ZMovement.Always0_2);

	int X, Y;
	X = Packet.XMovement - (Packet.Base.XSign ? 256 : 0);
	Y = Packet.YMovement - (Packet.Base.YSign ? 256 : 0);

	if (Packet.Base.XOverflow)
		X = 0;

	if (Packet.Base.YOverflow)
		Y = 0;

	mir.Type = INPUT_TYPE_MOUSE;
	mir.Device = MouseDevID;
	mir.Mouse.LeftButton = Packet.Base.LeftButton;
	mir.Mouse.RightButton = Packet.Base.RightButton;
	mir.Mouse.MiddleButton = Packet.Base.MiddleButton;
	mir.Mouse.Button4 = Packet.ZMovement.Button4;
	mir.Mouse.Button5 = Packet.ZMovement.Button5;
	mir.Mouse.X = X;
	mir.Mouse.Y = -Y;
	mir.Mouse.Z = Packet.ZMovement.Z;
	ReportInputEvent(&mir);
	PacketReady = false;
}

void MouseSampleRate(uint8_t SampleRate)
{
	PS2WriteCommand(PS2_CMD_WRITE_NEXT_BYTE_TO_PS2_PORT_2_INPUT);
	PS2WriteData(PS2_MOUSE_CMD_SET_SAMPLE_RATE);
	PS2ReadData();

	PS2WriteCommand(PS2_CMD_WRITE_NEXT_BYTE_TO_PS2_PORT_2_INPUT);
	PS2WriteData(SampleRate);
	PS2ReadData();
}

int __fs_ms_Ioctl(struct Inode *, unsigned long, void *)
{
	return 0;
}

const struct InodeOperations MouseOps = {
	.Ioctl = __fs_ms_Ioctl,
};

int InitializeMouse()
{
	PS2WriteData(PS2_CMD_WRITE_NEXT_BYTE_TO_PS2_PORT_2_INPUT);
	PS2WriteData(PS2_MOUSE_CMD_RESET);
	uint8_t test = PS2ReadData();
	if (test != PS2_MOUSE_RESP_TEST_PASSED &&
		test != PS2_MOUSE_RESP_ACK)
	{
		KernelLog("PS/2 mouse reset failed! (%#x)", test);
		return -EFAULT;
	}

	RegisterInterruptHandler(12, PS2MouseInterruptHandler);

	MouseDevID = RegisterDevice(INPUT_TYPE_MOUSE, &MouseOps);

	PS2WriteCommand(PS2_CMD_WRITE_NEXT_BYTE_TO_PS2_PORT_2_INPUT);
	PS2WriteData(PS2_MOUSE_CMD_SET_DEFAULTS);
	PS2ReadData();

	PS2WriteCommand(PS2_CMD_WRITE_NEXT_BYTE_TO_PS2_PORT_2_INPUT);
	PS2WriteData(PS2_MOUSE_CMD_ENABLE_DATA_REPORTING);

	MouseSampleRate(200);
	MouseSampleRate(100);
	MouseSampleRate(80);

	PS2WriteCommand(PS2_CMD_WRITE_NEXT_BYTE_TO_PS2_PORT_2_INPUT);
	PS2WriteData(PS2_MOUSE_CMD_READ_ID);
	uint8_t Device2ID = PS2ReadData();
	KernelLog("PS/2 Mouse ID: %#x", Device2ID);

	MouseSampleRate(200);
	MouseSampleRate(200);
	MouseSampleRate(80);

	PS2WriteCommand(PS2_CMD_WRITE_NEXT_BYTE_TO_PS2_PORT_2_INPUT);
	PS2WriteData(PS2_MOUSE_CMD_READ_ID);
	Device2ID = PS2ReadData();
	KernelLog("PS/2 Mouse ID: %#x", Device2ID);

	if (Device2ID >= 3 && Device2ID <= 4)
		FourPackets = true;
	if (Device2ID == 4)
		MouseButton45 = true;

	return 0;
}

int FinalizeMouse()
{
	PS2WriteCommand(PS2_CMD_WRITE_NEXT_BYTE_TO_PS2_PORT_2_INPUT);
	PS2WriteData(PS2_MOUSE_CMD_DISABLE_DATA_REPORTING);

	UnregisterDevice(MouseDevID);
	return 0;
}

int DetectPS2Mouse()
{
	PS2WriteCommand(PS2_CMD_WRITE_NEXT_BYTE_TO_PS2_PORT_2_INPUT);
	PS2WriteData(PS2_MOUSE_CMD_DISABLE_DATA_REPORTING);
	if (PS2ACKTimeout() != 0)
		KernelLog("PS/2 mouse failed to disable data reporting!");

	PS2WriteCommand(PS2_CMD_WRITE_NEXT_BYTE_TO_PS2_PORT_2_INPUT);
	PS2WriteData(PS2_MOUSE_CMD_READ_ID);
	if (PS2ACKTimeout() != 0)
		KernelLog("PS/2 mouse failed to read ID!");

	uint8_t recByte;
	int timeout = 1000000;
	while (timeout--)
	{
		recByte = PS2ReadData();
		if (recByte != PS2_ACK)
			break;
	}
	Device2ID[0] = recByte;

	timeout = 1000000;
	while (timeout--)
	{
		recByte = PS2ReadData();
		if (recByte != PS2_ACK)
			break;
	}
	Device2ID[1] = recByte;

	KernelLog("PS2 Mouse Device: 0x%X 0x%X", Device2ID[0], Device2ID[1]);
	return 0;
}