using UnityEngine;

public class OrbitCameraController : MonoBehaviour
{
    [SerializeField] private Transform target;       // The pivot point to orbit around
    [SerializeField] private float distance = 5f;     // Initial zoom distance
    [SerializeField] private float zoomSpeed = 2f;    // Scroll zoom sensitivity
    [SerializeField] private float minDistance = 2f;  // Min zoom
    [SerializeField] private float maxDistance = 15f; // Max zoom

    [SerializeField] private float rotationSpeed = 5f; // Mouse rotation sensitivity
    [SerializeField] private float minPitch = -80f;
    [SerializeField] private float maxPitch = 80f;

    private float yaw = 0f;
    private float pitch = 20f;

    [SerializeField] private float transitionDuration = 1f;
    private float transitionProgress = 1f; // 1 = done

    private Vector3 transitionStartPos;
    private Quaternion transitionStartRot;

    void LateUpdate()
    {
        if (target == null) return;

        // Always allow drag input, even during transition
        if (Input.GetMouseButton(0))
        {
            yaw += Input.GetAxis("Mouse X") * rotationSpeed;
            pitch -= Input.GetAxis("Mouse Y") * rotationSpeed;
            pitch = Mathf.Clamp(pitch, minPitch, maxPitch);
        }

        // Zoom
        float scroll = Input.GetAxis("Mouse ScrollWheel");
        distance -= scroll * zoomSpeed;
        distance = Mathf.Clamp(distance, minDistance, maxDistance);

        Quaternion targetRotation = Quaternion.Euler(pitch, yaw, 0);
        Vector3 targetOffset = targetRotation * new Vector3(0, 0, -distance);
        Vector3 desiredPosition = target.position + targetOffset;
        Quaternion desiredRotation = Quaternion.LookRotation(target.position - desiredPosition);

        if (transitionProgress < 1f)
        {
            transitionProgress += Time.deltaTime / transitionDuration;
            float t = Mathf.SmoothStep(0f, 1f, transitionProgress);

            // Interpolate from start to desired position & rotation
            transform.position = Vector3.Lerp(transitionStartPos, desiredPosition, t);
            transform.rotation = Quaternion.Slerp(transitionStartRot, desiredRotation, t);
        }
        else
        {
            // Normal orbit behavior
            transform.position = desiredPosition;
            transform.rotation = desiredRotation;
        }
    }


    public void UpdateTarget(Transform target)
    {
        this.target = target;
    }

    public void SmoothSetTarget(Transform newTarget)
    {
        if (newTarget == null || newTarget == target) return;

        // Store current camera position and rotation as transition start
        transitionStartPos = transform.position;
        transitionStartRot = transform.rotation;

        // Set new target
        target = newTarget;

        // Begin transition
        transitionProgress = 0f;
    }
}