using UnityEngine;

public class CarController : MonoBehaviour
{
    public float baseSpeed = 10f;
    public float turnSpeed = 50f;
    public AnimationCurve driftCurve;
    public Transform[] visualWheels;

    private Rigidbody rb;
    private float turnInput;
    private Vector2 startTouchPos;
    private Vector2 currentTouchPos;

    void Start()
    {
        rb = GetComponent<Rigidbody>();
        rb.centerOfMass = new Vector3(0, -0.5f, 0);
    }

    void Update()
    {
        // Touch input
        if (Input.touchCount > 0)
        {
            Touch touch = Input.GetTouch(0);

            switch (touch.phase)
            {
                case TouchPhase.Began:
                    startTouchPos = touch.position;
                    break;
                case TouchPhase.Moved:
                case TouchPhase.Stationary:
                    currentTouchPos = touch.position;
                    float horizontal = (currentTouchPos.x - startTouchPos.x) / Screen.width;
                    turnInput = Mathf.Clamp(horizontal, -1f, 1f);
                    break;
                case TouchPhase.Ended:
                    turnInput = 0f;
                    break;
            }
        }
        else
        {
            turnInput = 0f;
        }
    }

    void FixedUpdate()
    {
        float speed = baseSpeed;
        Vector3 forwardMove = transform.forward * speed * Time.fixedDeltaTime;
        rb.MovePosition(rb.position + forwardMove);

        float turnAmount = turnInput * turnSpeed * Time.fixedDeltaTime;
        Quaternion turnOffset = Quaternion.Euler(0, turnAmount, 0);
        rb.MoveRotation(rb.rotation * turnOffset);

        // Drift logic based on speed and angle
        Vector3 velocity = rb.velocity;
        float angle = Vector3.Angle(transform.forward, velocity);
        float driftFactor = driftCurve.Evaluate(angle);
        Vector3 driftDirection = Vector3.Lerp(velocity, transform.forward * velocity.magnitude, driftFactor);
        rb.velocity = new Vector3(driftDirection.x, rb.velocity.y, driftDirection.z);

        // Visual wheel rotation
        foreach (var wheel in visualWheels)
        {
            float rotationAmount = rb.velocity.magnitude * 10f;
            wheel.Rotate(Vector3.right, rotationAmount);
        }
    }
}