// WL-816f §2 — 「같은 화각·같은 거리」 바닥 비교용 렌더.
//   표준 바닥 카메라 = 직교 size 5 · euler(30,60,0) · 1080×1920 (814r/816a/816e 화각과 같은 방향)
//   데모는 에디트 모드에서 인스턴싱을 직접 발행해 그린다(데모 씬 Play 금지 · §9).
public static class WL816f_Cmp
{
    public const string Dir = "Screenshots_WL/WL816f/";
    public const int W = 1080, H = 1920;

    // ── 데모 바닥 ──────────────────────────────────────────────────────
    public static void Demo()
    {
        UnityEditor.SceneManagement.EditorSceneManager.OpenScene(
            "Assets/3DPixelArtEnvironment/Demo/Demo.unity", UnityEditor.SceneManagement.OpenSceneMode.Single);

        var sb = new System.Text.StringBuilder();
        // 평평한 풀밭 지점을 찾는다(경사가 작고 1층 스플랫이 지배적인 곳)
        var terr = UnityEngine.Object.FindFirstObjectByType<UnityEngine.Terrain>();
        UnityEngine.Vector3 spot = new UnityEngine.Vector3(130f, 0f, 90f);
        if (terr != null)
        {
            var td = terr.terrainData;
            float best = 999f;
            for (float x = 40f; x < 180f; x += 10f)
                for (float z = 40f; z < 180f; z += 10f)
                {
                    float u = x / td.size.x, v = z / td.size.z;
                    var nrm = td.GetInterpolatedNormal(u, v);
                    float slope = 1f - nrm.y;
                    var c = td.alphamapTextures[0].GetPixelBilinear(u, v);
                    if (c.r < 0.9f) continue;                      // 1층(풀)이 지배적인 곳만
                    if (slope < best) { best = slope; spot = new UnityEngine.Vector3(x, td.GetInterpolatedHeight(u, v) + terr.transform.position.y, z); }
                }
            sb.AppendLine("데모 바닥 지점 " + spot.ToString("F2") + " slope=" + best.ToString("F4"));
        }

        var cam = GroundCam(spot, 6f);
        int n = WL816f_Inst.Publish(sb);
        Shoot(cam, Dir + "x_demo_ground.png", sb);
        // 넓은 화각(ortho 10)도 하나
        cam = GroundCam(spot, 10f);
        WL816f_Inst.Publish(sb);
        Shoot(cam, Dir + "x_demo_wide.png", sb);
        sb.AppendLine("데모 인스턴싱 구성 " + n);
        System.IO.File.WriteAllText("AgentScripts/WL816f_DEMO.txt", sb.ToString());
        UnityEngine.Debug.Log(sb.ToString());
    }

    /// <summary>표준 바닥 카메라 — 지점 spot 을 데모 화각으로 본다.</summary>
    public static UnityEngine.Camera GroundCam(UnityEngine.Vector3 spot, float size)
    {
        var go = UnityEngine.GameObject.Find("~WL816fGroundCam");
        if (go == null) { go = new UnityEngine.GameObject("~WL816fGroundCam"); go.hideFlags = UnityEngine.HideFlags.DontSave; }
        var c = go.GetComponent<UnityEngine.Camera>();
        if (c == null) c = go.AddComponent<UnityEngine.Camera>();
        c.orthographic = true; c.orthographicSize = size;
        c.nearClipPlane = 0.3f; c.farClipPlane = 500f;
        c.clearFlags = UnityEngine.CameraClearFlags.SolidColor;
        c.backgroundColor = new UnityEngine.Color(0.192f, 0.302f, 0.475f, 1f);
        c.cullingMask = ~0; c.depth = -100f;
        var rot = UnityEngine.Quaternion.Euler(30f, 60f, 0f);
        go.transform.rotation = rot;
        go.transform.position = spot - rot * UnityEngine.Vector3.forward * 60f;
        if (go.GetComponent<UnityEngine.Rendering.Universal.UniversalAdditionalCameraData>() == null)
            go.AddComponent<UnityEngine.Rendering.Universal.UniversalAdditionalCameraData>();
        return c;
    }

    public static void Shoot(UnityEngine.Camera cam, string path, System.Text.StringBuilder sb)
    {
        if (cam == null) { if (sb != null) sb.AppendLine("카메라 없음 " + path); return; }
        System.IO.Directory.CreateDirectory(System.IO.Path.GetDirectoryName(path));
        var rt = new UnityEngine.RenderTexture(W, H, 24, UnityEngine.RenderTextureFormat.ARGB32, UnityEngine.RenderTextureReadWrite.sRGB);
        rt.antiAliasing = 1; rt.Create();
        var prevT = cam.targetTexture; var prevA = UnityEngine.RenderTexture.active;
        cam.targetTexture = rt; cam.Render();
        UnityEngine.RenderTexture.active = rt;
        var tex = new UnityEngine.Texture2D(W, H, UnityEngine.TextureFormat.RGB24, false);
        tex.ReadPixels(new UnityEngine.Rect(0, 0, W, H), 0, 0); tex.Apply();
        System.IO.File.WriteAllBytes(path, UnityEngine.ImageConversion.EncodeToPNG(tex));
        UnityEngine.RenderTexture.active = prevA; cam.targetTexture = prevT;
        UnityEngine.Object.DestroyImmediate(tex);
        rt.Release(); UnityEngine.Object.DestroyImmediate(rt);
        WL816f_Inst.Free();
        if (sb != null) sb.AppendLine("캡처 " + path);
    }
}

/// <summary>에디트 모드에서 InstancesBehaviour 가 그릴 것을 이번 프레임에 직접 발행한다(Play 없이).</summary>
public static class WL816f_Inst
{
    static readonly System.Collections.Generic.List<Environment.Instancing.InstancingConfiguration> s_pending
        = new System.Collections.Generic.List<Environment.Instancing.InstancingConfiguration>();

    public static int Publish(System.Text.StringBuilder sb)
    {
        int n = 0; long inst = 0;
        var bs = UnityEngine.Object.FindObjectsByType<Environment.Instancing.InstancesBehaviour>(
            UnityEngine.FindObjectsInactive.Exclude, UnityEngine.FindObjectsSortMode.None);
        for (int i = 0; i < bs.Length; i++)
        {
            var b = bs[i];
            System.Collections.Generic.Dictionary<Environment.Instancing.InstancingSettings,
                System.Collections.Generic.List<Environment.Instancing.InstanceData>> data = null;
            try { data = b.GetInstanceData(); } catch { continue; }
            if (data == null) continue;
            var bounds = b.CalculateInstancesBounds();
            var l2w = b.transform.localToWorldMatrix; l2w.m03 = 0; l2w.m13 = 0; l2w.m23 = 0;
            foreach (var kv in data)
            {
                if (kv.Value == null || kv.Value.Count == 0) continue;
                var cfg = new Environment.Instancing.InstancingConfiguration(kv.Key, kv.Value, "_InstanceData");
                cfg.MaterialPropertyBlock.SetMatrix("_LocalToWorld", l2w);
                UnityEngine.Graphics.DrawMeshInstancedIndirect(cfg.Mesh, 0, cfg.Material, bounds, cfg.CommandBuffer, 0,
                    cfg.MaterialPropertyBlock, UnityEngine.Rendering.ShadowCastingMode.Off, false, 0);
                n++; inst += kv.Value.Count;
                s_pending.Add(cfg);
            }
        }
        if (sb != null) sb.AppendLine("  인스턴스 " + inst + " (구성 " + n + ")");
        return n;
    }

    public static void Free()
    {
        for (int i = 0; i < s_pending.Count; i++) s_pending[i].FreeMemory();
        s_pending.Clear();
    }
}