using UnityEngine;
using System.Collections.Generic;

public class FenceSpawner : MonoBehaviour
{
    public Transform waypointsParent;      // Parent object holding ordered waypoint transforms
    public GameObject fencePrefab;         // Prefab of your fence segment
    public float segmentSpacing = 1f;      // Spacing between repeated segments
    public float sideOffset = 2.5f;        // Distance from center of the road

    void Start()
    {
        List<Transform> waypoints = new List<Transform>();
        foreach (Transform child in waypointsParent)
        {
            waypoints.Add(child);
        }

        if (waypoints.Count < 2)
        {
            Debug.LogError("❌ Not enough waypoints.");
            return;
        }

        Quaternion lastRotation = Quaternion.identity;

        for (int i = 0; i < waypoints.Count - 1; i++)
        {
            Vector3 start = waypoints[i].position;
            Vector3 end = waypoints[i + 1].position;

            // Smooth forward direction using a look-ahead if possible
            Vector3 forward;
            if (i < waypoints.Count - 2)
                forward = (waypoints[i + 2].position - start).normalized;
            else
                forward = (end - start).normalized;

            Vector3 flatForward = new Vector3(forward.x, 0f, forward.z).normalized;
            Vector3 right = Vector3.Cross(Vector3.up, flatForward);

            // Compute rotation and smooth it
            Quaternion baseRotation = Quaternion.LookRotation(flatForward, Vector3.up);
            Quaternion smoothedRotation = (i == 0) ? baseRotation : Quaternion.Slerp(lastRotation, baseRotation, 0.5f);
            lastRotation = smoothedRotation;

            // Apply prefab orientation correction
            //Quaternion finalRotation = smoothedRotation; // if your fence needs X+90
            Quaternion finalRotation = smoothedRotation * Quaternion.Euler(90, 0, -90); // if your fence needs X+90

            // How many fence segments between this pair
            float segmentLength = Vector3.Distance(start, end);
            int steps = Mathf.CeilToInt(segmentLength / segmentSpacing);

            for (int j = 0; j <= steps; j++)
            {
                float t = j / (float)steps;
                Vector3 center = Vector3.Lerp(start, end, t);
                Vector3 leftPos = center - right * sideOffset;
                Vector3 rightPos = center + right * sideOffset;

                Instantiate(fencePrefab, leftPos, finalRotation, transform);
                Instantiate(fencePrefab, rightPos, finalRotation, transform);
            }
        }

        Debug.Log("✅ Fence wall generated from waypoints.");
    }

}