using UnityEngine;

[AddComponentMenu("Camera/Top Down Follow Camera")]
public class TopDownCameraController : MonoBehaviour
{
    [Header("Target")]
    public Transform target;

    [Header("Positioning")]
    public float distance = 8f;            // horizontal distance from target
    public float height = 6f;              // vertical offset above target
    [Range(0f, 89f)]
    public float pitch = 80f;              // X rotation in degrees (80 by default)

    [Header("Smoothing")]
    public bool smoothPosition = true;
    public float positionSmoothTime = 0.12f;
    public bool smoothRotation = true;
    public float rotationSmoothTime = 0.08f;

    Vector3 positionVelocity;
    Quaternion rotationVelocity;

    void Reset()
    {
        pitch = 80f;
        distance = 8f;
        height = 6f;
    }

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

        // Calculate desired camera position in local space relative to target
        // Start with a rotation that looks down by 'pitch' degrees
        Quaternion pitchRot = Quaternion.Euler(pitch, 0f, 0f);

        // Desired offset: move back along the camera's forward by 'distance', then up by 'height'
        Vector3 localOffset = pitchRot * new Vector3(0f, height, -distance);

        Vector3 desiredPosition = target.position + localOffset;

        // Smooth position
        if (smoothPosition)
        {
            transform.position = Vector3.SmoothDamp(transform.position, desiredPosition, ref positionVelocity, positionSmoothTime);
        }
        else
        {
            transform.position = desiredPosition;
        }

        // Desired rotation: look at target but keep the pitch
        Vector3 lookDirection = (target.position - transform.position).normalized;
        Quaternion desiredRotation = Quaternion.LookRotation(lookDirection, Vector3.up);

        // Optionally lock X rotation to the pitch value to avoid subtle tilts
        Vector3 euler = desiredRotation.eulerAngles;
        euler.x = pitch;
        desiredRotation = Quaternion.Euler(euler);

        // Smooth rotation
        if (smoothRotation)
        {
            transform.rotation = Quaternion.Slerp(transform.rotation, desiredRotation, 1f - Mathf.Exp(-rotationSmoothTime * 60f * Time.deltaTime));
        }
        else
        {
            transform.rotation = desiredRotation;
        }
    }
}