#if UNITY_EDITOR
using UnityEditor;
using UnityEngine;

/// <summary>
/// 把 CaoCao Prefab 摆到当前场景广场中心，Y 取地表碰撞高度。不保存进 TownSquare.prefab。
/// </summary>
public static class PlaceCaoCao
{
    const string PrefabPath = "Assets/Bundles/Characters/Human/CaoCao/CaoCao.prefab";

    public static string Run()
    {
        var prefab = AssetDatabase.LoadAssetAtPath<GameObject>(PrefabPath);
        if (prefab == null)
            return "missing " + PrefabPath;

        var existing = GameObject.Find("CaoCao_Preview");
        if (existing != null)
            Object.DestroyImmediate(existing);

        var go = (GameObject)PrefabUtility.InstantiatePrefab(prefab);
        go.name = "CaoCao_Preview";

        Physics.SyncTransforms();
        var y = SampleGroundY(0f, 0f, out var sitInfo);
        go.transform.position = new Vector3(0f, y, 0f);
        go.transform.rotation = Quaternion.identity;

        var bounds = default(Bounds);
        var has = false;
        foreach (var r in go.GetComponentsInChildren<Renderer>())
        {
            if (!has) { bounds = r.bounds; has = true; }
            else bounds.Encapsulate(r.bounds);
        }
        return $"pos={go.transform.position} h={(has ? bounds.size.y : 0f):F3} groundY={y:F3} {sitInfo}";
    }

    static float SampleGroundY(float x, float z, out string info)
    {
        var plaza = GameObject.Find("TownSquare");
        var cols = plaza != null
            ? plaza.GetComponentsInChildren<MeshCollider>()
            : Object.FindObjectsByType<MeshCollider>(FindObjectsSortMode.None);
        var y = 0f;
        var hitAny = false;
        var best = float.MaxValue;
        var meshName = "";
        var boundsTop = 0f;
        foreach (var col in cols)
        {
            if (col == null || !col.enabled) continue;
            meshName = col.sharedMesh != null ? col.sharedMesh.name : "null";
            boundsTop = col.bounds.max.y;
            var origins = new[]
            {
                new Vector3(x, 80f, z),
                new Vector3(col.bounds.center.x, col.bounds.max.y + 8f, col.bounds.center.z),
                new Vector3(x + 0.35f, 80f, z + 0.35f),
            };
            foreach (var origin in origins)
            {
                var ray = new Ray(origin, Vector3.down);
                if (!col.Raycast(ray, out var hit, 160f)) continue;
                if (hit.distance >= best) continue;
                best = hit.distance;
                y = hit.point.y;
                hitAny = true;
            }
        }
        if (!hitAny && boundsTop > 0.01f)
        {
            y = boundsTop;
            info = $"fallbackBoundsTop={y:F3} mesh={meshName} cols={cols.Length}";
            return y;
        }
        info = $"plaza={(plaza != null ? plaza.name : "null")} cols={cols.Length} mesh={meshName} meshHit={hitAny}";
        return hitAny ? y : 0f;
    }
}
#endif