using Godot;

public partial class PlayerCamera : Camera3D
{
    [ExportCategory("Camera Movement")]
    [Export] public float CameraPanSpeed { get; set; } = 20f;
    [Export] public float CameraZoomSpeed { get; set; } = 20f;
    [Export] public float CameraZoomMin { get; set; } = 10f;
    [Export] public float CameraZoomMax { get; set; } = 50f;

    [ExportCategory("Edge Scrolling")]
    [Export] public float EdgeScrollMargin { get; set; } = 20f;
    [Export] public float EdgeScrollSpeed { get; set; } = 15f;

    [ExportCategory("Rotation")]
    [Export] public float YawSensitivity { get; set; } = 0.5f;
    [Export] public float PitchSensitivity { get; set; } = 0.18f;
    [Export] public float StepDegreeMax { get; set; } = 3f;
    [Export] public float PitchDegreeMin { get; set; } = 10f;
    [Export] public float PitchDegreeMax { get; set; } = 80f;
    [Export] public bool CaptureMiddleButton { get; set; } = false;

    Vector3 origin = Vector3.Zero;
    float orbitDistance = 25f;
    float currentHeight = 20f;
    float orbitRadius = 20f;
    bool isMiddleMouseRotating = false;
    float yaw = 0f;
    float pitch = 0f;

    public override void _Ready()
    {
        var pitchMin = Mathf.DegToRad(PitchDegreeMin);
        var pitchMax = Mathf.DegToRad(PitchDegreeMax);

        pitch = Mathf.Clamp(pitch, pitchMin, pitchMax);

        UpdateCameraPosition();
    }

    public override void _Process(double delta)
    {
        var movement = Vector3.Zero;

        // Keyboard Input
        if (Input.IsActionPressed("camera_pan_right"))
        {
            movement.X += 1f;
        }
        if (Input.IsActionPressed("camera_pan_left"))
        {
            movement.X -= 1f;
        }
        if (Input.IsActionPressed("camera_pan_up"))
        {
            movement.Z += 1f;
        }
        if (Input.IsActionPressed("camera_pan_down"))
        {
            movement.Z -= 1f;
        }

        // Edge Scrolling
        var mousePosition = GetViewport().GetMousePosition();
        var viewportSize = GetViewport().GetVisibleRect().Size;

        if (mousePosition.X < EdgeScrollMargin)
        {
            movement.X -= 1f;
        }
        if (mousePosition.X > viewportSize.X - EdgeScrollMargin)
        {
            movement.X += 1f;
        }
        if (mousePosition.Y < EdgeScrollMargin)
        {
            movement.Z -= 1f;
        }
        if (mousePosition.Y > viewportSize.Y - EdgeScrollMargin)
        {
            movement.Z += 1f;
        }

        // Rotating
        if (movement.Length() > 0f)
        {
            movement = movement.Normalized().Rotated(Vector3.Up, yaw);
            origin += movement * CameraPanSpeed * (float)delta;

            UpdateCameraPosition();
        }
    }

    public override void _UnhandledInput(InputEvent @event)
    {
        if (@event is InputEventMouseButton mouseButtonEvent)
        {
            if (mouseButtonEvent.Pressed)
            {
                var delta = (float)GetProcessDeltaTime();

                if (mouseButtonEvent.ButtonIndex is MouseButton.WheelUp)
                {
                    orbitDistance = Mathf.Max(CameraZoomMin, orbitDistance - CameraZoomSpeed * delta);
                }
                else if (mouseButtonEvent.ButtonIndex is MouseButton.WheelDown)
                {
                    orbitDistance = Mathf.Min(CameraZoomMax, orbitDistance + CameraZoomSpeed * delta);
                }

                UpdateCameraPosition();
            }

            if (mouseButtonEvent.ButtonIndex is MouseButton.Middle)
            {
                isMiddleMouseRotating = mouseButtonEvent.Pressed;

                if (CaptureMiddleButton)
                {
                    Input.MouseMode = mouseButtonEvent.Pressed
                        ? Input.MouseModeEnum.Captured
                        : Input.MouseModeEnum.Visible;
                }
            }
        }
        else if (@event is InputEventMouseMotion mouseMotionEvent && isMiddleMouseRotating)
        {
            var viewportSize = GetViewport().GetVisibleRect().Size;
            var viewMin = (float)Mathf.Min(viewportSize.X, viewportSize.Y);
            var delta = (float)GetProcessDeltaTime() * 60f;

            // px => normalized fraction of screen -> radians, scaled by dt
            var dx = (mouseMotionEvent.Relative.X / viewMin) * YawSensitivity * Mathf.Tau * delta;
            var dy = (mouseMotionEvent.Relative.Y / viewMin) * PitchSensitivity * Mathf.Tau * delta;

            // Safety cap per event
            var maxStep = Mathf.DegToRad(StepDegreeMax);

            dx = Mathf.Clamp(dx, -maxStep, maxStep);
            dy = Mathf.Clamp(dy, -maxStep, maxStep);

            yaw -= dx;
            pitch += dy;

            var pitchMin = Mathf.DegToRad(PitchDegreeMin);
            var pitchMax = Mathf.DegToRad(PitchDegreeMax);

            pitch = Mathf.Clamp(pitch, pitchMax, pitchMax);

            UpdateCameraPosition();
        }
    }

    void UpdateCameraPosition()
    {
        var direction = new Vector3(
            x: Mathf.Sin(yaw) * Mathf.Cos(pitch),
            y: Mathf.Sin(pitch),
            z: Mathf.Cos(yaw) * Mathf.Cos(pitch)
        ).Normalized();

        Position = origin + direction * orbitDistance;
        LookAt(origin, Vector3.Up);

        currentHeight = orbitDistance * Mathf.Sin(pitch);
        orbitRadius = orbitDistance * Mathf.Cos(pitch);
    }
}