package inputs

import (
	"fmt"

	"github.com/karalabe/hid"
)

type JoystickEvent struct {
	Time   uint32 // Event timestamp in milliseconds
	Value  int16  // Value of the event (button press or axis movement)
	Type   uint8  // Event type (button or axis)
	Number uint8  // Axis/button number
}

const (
	JS_EVENT_BUTTON = 0x01 // Button pressed/released
	JS_EVENT_AXIS   = 0x02 // Joystick moved
	JS_EVENT_INIT   = 0x80 // Initial state of device
)

type Controller struct {
	Device *hid.Device
}

func (c *Controller) ReadState() error {
	buf := make([]byte, 64)
	_, err := c.Device.Read(buf)
	if err != nil {
		return err
	}

	fmt.Printf("Joystick: X=%d Y=%d Buttons=%08b\n", buf[0], buf[1], buf[6])
	return nil
}

type Vec2B struct {
	X, Y byte
}

type ControllerState struct {
	joystick Vec2B
	buttons  byte
}

type ConjureControllerButton int

const (
	ButtonA ConjureControllerButton = iota //0
	ButtonB
	ButtonC

	Button1
	Button2
	Button3

	ButtonStart
	ButtonPower // 7
)

var ConjureControllerButtons = []ConjureControllerButton{
	ButtonA,
	ButtonB,
	ButtonC,

	Button1,
	Button2,
	Button3,

	ButtonStart,
	ButtonPower,
}

func (s ConjureControllerButton) String() string {
	switch s {
	case ButtonA:
		return "ButtonA"
	case ButtonB:
		return "ButtonB"
	case ButtonC:
		return "ButtonC"
	case Button1:
		return "Button1"
	case Button2:
		return "Button2"
	case Button3:
		return "Button3"
	case ButtonStart:
		return "ButtonStart"
	case ButtonPower:
		return "ButtonPower"
	default:
		return "Unknown"
	}
}

func Start(onStateChange func(any)) {
	fmt.Println("Opening devices")
	const vendorID = 0x0079
	const productID = 0x0006

	// Enumerate all matching devices
	devices := hid.Enumerate(vendorID, productID)
	if len(devices) == 0 {
		fmt.Printf("Device with VID:PID %04X:%04X not found", vendorID, productID)
		return
	}

	for _, d := range devices {
		fmt.Printf("Found: %s - VID:%04X PID:%04X\n", d.Product, d.VendorID, d.ProductID)
	}

	// Open the first matching device
	device, err := devices[0].Open()
	if err != nil {
		fmt.Printf("Failed to open device: %v", err)
		return
	}
	defer device.Close()

	fmt.Println("Reading data... Press Ctrl+C to exit")

	buf := make([]byte, 32) // Adjust size if needed
	for {
		_, err := device.Read(buf)
		if err != nil {
			fmt.Printf("Read error: %v", err)
			return
		}

		// For debugging: print raw data
		// fmt.Printf("Raw: % X\n", buf[:n])

		// Example: decode joystick + button state
		x := buf[0]       // Horizontal axis (0–255)
		y := buf[1]       // Vertical axis (0–255)
		buttons := buf[6] // Buttons as bitfield
		state := ControllerState{
			joystick: Vec2B{x, y},
			buttons:  buttons,
		}

		// fmt.Printf("Joystick X: %d, Y: %d, Buttons: %08b\n", x, y, buttons)

		if buttons != 0 {
			for _, button := range ConjureControllerButtons {
				if buttons&(1<<button) != 0 {
					fmt.Printf("Button %s pressed\n", (button + 1).String())
				}
			}
			onStateChange(state)
			fmt.Printf("Button was pressed! %d\n", buttons)
		}

		if x != 127 || y != 127 {
			onStateChange(state)
			fmt.Printf("Joystick moved! %d - %d\n", x, y)
		}
	}

	fmt.Println("Out")

	// Open the joystick device file
	// file, err := os.Open("/dev/input/js0")
	// if err != nil {
	// 	fmt.Println("Error opening joystick:", err)
	// 	return
	// }
	// defer file.Close()

	// // Continuously read joystick events
	// for {
	// 	var e JoystickEvent
	// 	err := binary.Read(file, binary.LittleEndian, &e)
	// 	if err != nil {
	// 		fmt.Println("Error reading joystick event:", err)
	// 		return
	// 	}

	// 	// Handle the event
	// 	handleJoystickEvent(e)

	// 	// Sleep to avoid flooding output
	// 	time.Sleep(10 * time.Millisecond)
	// }
}

// handleJoystickEvent processes joystick events.
func handleJoystickEvent(e JoystickEvent) {
	if e.Type&JS_EVENT_INIT != 0 {
		// Ignore initial state events
		return
	}

	if e.Type&JS_EVENT_BUTTON != 0 {
		if e.Value == 1 {
			fmt.Printf("Button %d pressed\n", e.Number)
		} else {
			fmt.Printf("Button %d released\n", e.Number)
		}
	}

	if e.Type&JS_EVENT_AXIS != 0 {
		fmt.Printf("Axis %d moved to %d\n", e.Number, e.Value)
	}
}