#if UNITY_EDITOR
using System.IO;
using System.Linq;
using UnityEditor;
using UnityEditor.SceneManagement;
using UnityEngine;
using UnityEngine.SceneManagement;

/// <summary>White-albedo XTerrain capture to prove lightmap shade is reaching the ground shader.</summary>
public static class DiagnoseGroundWhiteGi
{
    const string Root = "Assets/Bundles/Scenes/Town/HomeCamp";
    const string ScenePath = Root + "/HomeCamp.unity";
    const string Review = "D:/UD/AI/AIGame/Tools/output/homecamp_review";

    public static string Run()
    {
        AssetDatabase.ImportAsset("Assets/Bundles/Shaders/XShader/XTerrain.shader", ImportAssetOptions.ForceSynchronousImport);
        var scene = EditorSceneManager.OpenScene(ScenePath, OpenSceneMode.Single);
        var root = scene.GetRootGameObjects().Single(g => g.name == "HomeCamp");
        var ground = root.transform.Find("Ground")?.GetComponentInChildren<MeshRenderer>();
        if (!ground) return "FAIL";

        var prev = ground.sharedMaterial;
        var mat = Object.Instantiate(prev);
        var white = Texture2D.whiteTexture;
        mat.SetTexture("_LayerTex0", white); mat.SetTexture("_LayerTex1", white);
        mat.SetTexture("_LayerTex2", white); mat.SetTexture("_LayerTex3", white);
        mat.SetFloat("_LightmapContrast", 1f);
        mat.SetFloat("_BumpScale", 0f); mat.SetFloat("_Roughness", 1.5f); mat.SetFloat("_Metallic", 0f);
        ground.sharedMaterial = mat;

        ShaderUtil.allowAsyncCompilation = false;
        var cam = root.GetComponentInChildren<Camera>();
        Capture(cam, Review + "/diag_xterrain_white_c1.png");

        mat.SetFloat("_LightmapContrast", 2.2f);
        Capture(cam, Review + "/diag_xterrain_white_c22.png");

        ground.sharedMaterial = prev;
        Object.DestroyImmediate(mat);
        return "wrote white-gi captures contrastProp=" + prev.GetFloat("_LightmapContrast");
    }

    static void Capture(Camera camera, string file)
    {
        var rt = RenderTexture.GetTemporary(720, 1280, 24, RenderTextureFormat.ARGB32);
        var old = RenderTexture.active; var oldT = camera.targetTexture; var oldA = camera.aspect;
        var tex = new Texture2D(720, 1280, TextureFormat.RGB24, false);
        try
        {
            camera.aspect = 720f / 1280; camera.targetTexture = rt; RenderTexture.active = rt;
            camera.Render(); camera.Render();
            tex.ReadPixels(new Rect(0, 0, 720, 1280), 0, 0); tex.Apply();
            File.WriteAllBytes(file, tex.EncodeToPNG());
        }
        finally
        {
            camera.targetTexture = oldT; camera.aspect = oldA; RenderTexture.active = old;
            RenderTexture.ReleaseTemporary(rt); Object.DestroyImmediate(tex);
        }
    }
}
#endif