using Godot;

public partial class Player : CharacterBody3D
{
	[Export] Control GameMenu;

	[Export] public float Speed = 5f;
	[Export] public float JumpForce = 5f;
	[Export] public float MouseSensitivity = 0.2f;

	private Vector3 gravityVelocity = Vector3.Zero;
	private Vector3 movementVelocity = Vector3.Zero;
	private float cameraPitch = 0f;
	private Camera3D camera;
	private GravityReceiver gravityReceiver;

	public override void _Ready()
	{
		camera = GetNode<Camera3D>("Camera");
		gravityReceiver = GetNode<GravityReceiver>("GravityReceiver");
	}

	public override void _PhysicsProcess(double delta)
	{
		Vector3 newGravityVelocity = gravityVelocity;
		Vector3 newMovementVelocity = movementVelocity;

		if (IsInGravity())
		{
			ProcessGravity(delta, ref newGravityVelocity);
			if (!GameMenu.Visible)
			{
				ProcessControlsGravity(ref newGravityVelocity, ref newMovementVelocity);
			}
		}
		else
		{
			newGravityVelocity = Vector3.Zero;

			ProcessCamera(delta);
			if (!GameMenu.Visible)
			{
				ProcessControls(ref newMovementVelocity);
			}
		}

		gravityVelocity = newGravityVelocity;
		movementVelocity = newMovementVelocity;
		Velocity = newGravityVelocity + newMovementVelocity;

		MoveAndSlide();
	}

	public override void _Input(InputEvent @event)
	{
		if (GameMenu.Visible)
		{
			return;
		}

		if (@event is InputEventMouseMotion motion)
		{
			float yawDelta = -motion.Relative.X * MouseSensitivity;
			float yawDeltaRad = Mathf.DegToRad(yawDelta);
			float pitchDelta = -motion.Relative.Y * MouseSensitivity;
			float pitchDeltaRad = Mathf.DegToRad(pitchDelta);

			RotateObjectLocal(Vector3.Up, yawDeltaRad);

			if (IsInGravity())
			{
				cameraPitch = Mathf.Clamp(cameraPitch + pitchDelta, -90f, 90f);
			}
			else
			{
				RotateObjectLocal(Vector3.Right, pitchDeltaRad);
			}

			camera.RotationDegrees = new Vector3(cameraPitch, 0, 0);
		}
	}

	public bool IsInGravity()
	{
		return gravityReceiver.InGravityZone && gravityReceiver.GravityStrength > 0f;
	}

	public bool IsOnGravityFloor()
	{
		for (int i = 0; i < GetSlideCollisionCount(); i++)
		{
			KinematicCollision3D collision = GetSlideCollision(i);
			Vector3 collisionNormal = collision.GetNormal();

			float alignment = collisionNormal.Dot(gravityReceiver.GravityDirection);

			if (alignment > 0.7f)
			{
				return true;
			}
		}

		return false;
	}

	private void ProcessGravity(double delta, ref Vector3 newGravityVelocity)
	{
		if (!IsOnGravityFloor())
		{
			newGravityVelocity -= gravityReceiver.GravityDirection * gravityReceiver.GravityStrength * (float)delta;
		}
		else
		{
			newGravityVelocity = -gravityReceiver.GravityDirection;
		}

		Vector3 currentUp = GlobalTransform.Basis.Y;
		Vector3 targetUp = gravityReceiver.GravityDirection;

		Vector3 axis = currentUp.Cross(targetUp);
		if (axis.Length() < 0.00001f)
		{
			return;
		}
		float angle = currentUp.AngleTo(targetUp);

		Rotate(axis.Normalized(), angle * (float)delta * 10f);
	}

	private void ProcessCamera(double delta)
	{
		if (cameraPitch > 0.01f)
		{
			cameraPitch -= 90f * (float)delta;
		}
		else if (cameraPitch < -0.001f)
		{
			cameraPitch += 90f * (float)delta;
		}
		if (Mathf.Abs(cameraPitch) < 1f)
		{
			cameraPitch = 0f;
		}
		camera.RotationDegrees = new Vector3(cameraPitch, 0, 0);
	}

	private void ProcessControlsGravity(ref Vector3 newGravityVelocity, ref Vector3 newMovementVelocity)
	{
		float inputX = Input.GetAxis("move_left", "move_right");
		float inputZ = Input.GetAxis("move_forward", "move_back");

		Vector3 direction = Transform.Basis.X * inputX + Transform.Basis.Z * inputZ;

		if (direction != Vector3.Zero)
		{
			newMovementVelocity.X = direction.X * Speed;
			newMovementVelocity.Y = direction.Y * Speed;
			newMovementVelocity.Z = direction.Z * Speed;
		}
		else
		{
			newMovementVelocity.X = 0f;
			newMovementVelocity.Y = 0f;
			newMovementVelocity.Z = 0f;
		}

		if (Input.IsActionJustPressed("jump") && IsOnGravityFloor())
		{
			newGravityVelocity = gravityReceiver.GravityDirection * JumpForce;
		}
	}

	private void ProcessControls(ref Vector3 newMovementVelocity)
	{
		float inputX = Input.GetAxis("move_left", "move_right");
		float inputY = -Input.GetAxis("move_up", "move_down");
		float inputZ = Input.GetAxis("move_forward", "move_back");

		Vector3 direction = Transform.Basis.X * inputX + Transform.Basis.Y * inputY + Transform.Basis.Z * inputZ;

		if (direction != Vector3.Zero)
		{
			newMovementVelocity.X = direction.X * Speed;
			newMovementVelocity.Y = direction.Y * Speed;
			newMovementVelocity.Z = direction.Z * Speed;
		}
		else
		{
			newMovementVelocity.X = 0f;
			newMovementVelocity.Y = 0f;
			newMovementVelocity.Z = 0f;
		}

		float inputRotateZ = Input.GetAxis("rotate_left", "rotate_right");

		float rotateAmountZ = Mathf.DegToRad(inputRotateZ);

		RotateObjectLocal(Vector3.Forward, rotateAmountZ);
	}
}