using UnityEditor;
using UnityEditor.SceneManagement;
using UnityEngine;
using UnityEngine.Rendering;

/// <summary>
/// 투명 데스크톱 오버레이 검증에 필요한 프로젝트 설정을 일괄 적용한다.
/// 일부 항목은 인스펙터에 노출되지 않아 스크립트로 설정한다.
/// </summary>
public static class DesktopOverlaySetup
{
    const BuildTarget Target = BuildTarget.StandaloneWindows64;

    [MenuItem("Tools/Desktop Overlay/1. Apply Transparent Window Settings")]
    public static void Apply()
    {
        // useFlipModelSwapchain 은 D3D11 전용이므로 API 를 고정한다.
        PlayerSettings.SetUseDefaultGraphicsAPIs(Target, false);
        PlayerSettings.SetGraphicsAPIs(Target, new[] { GraphicsDeviceType.Direct3D11 });

        PlayerSettings.useFlipModelSwapchain = false;   // DWM 투명도의 전제 조건

        PlayerSettings.fullScreenMode = FullScreenMode.Windowed;
        PlayerSettings.runInBackground = true;
        PlayerSettings.visibleInBackground = true;
        PlayerSettings.resizableWindow = false;
        PlayerSettings.forceSingleInstance = true;

        AssetDatabase.SaveAssets();
        Debug.Log("[DesktopOverlaySetup] Player Settings 적용 완료.");
        LogCurrent();
    }

    [MenuItem("Tools/Desktop Overlay/2. Log Current Settings")]
    public static void LogCurrent()
    {
        var apis = PlayerSettings.GetGraphicsAPIs(Target);
        var apiList = string.Join(", ", System.Array.ConvertAll(apis, a => a.ToString()));

        Debug.Log(
            "[DesktopOverlaySetup] 현재 값 (괄호 안이 기대값)\n" +
            $"  Graphics APIs         = [{apiList}]   (Direct3D11)\n" +
            $"  Auto Graphics API     = {PlayerSettings.GetUseDefaultGraphicsAPIs(Target)}   (False)\n" +
            $"  useFlipModelSwapchain = {PlayerSettings.useFlipModelSwapchain}   (False)\n" +
            $"  fullScreenMode        = {PlayerSettings.fullScreenMode}   (Windowed)\n" +
            $"  runInBackground       = {PlayerSettings.runInBackground}   (True)\n" +
            $"  visibleInBackground   = {PlayerSettings.visibleInBackground}   (True)"
        );
    }

    /// <summary>
    /// HDR 32비트 컬러 버퍼(R11G11B10_UFloat)에는 알파 채널이 없어서
    /// 카메라를 알파 0으로 클리어해도 저장되지 않는다. HDR 을 끄고
    /// URP 의 Alpha Processing 을 켠다.
    /// </summary>
    [MenuItem("Tools/Desktop Overlay/3. Fix URP Alpha Settings")]
    public static void FixUrpAlpha()
    {
        var guids = AssetDatabase.FindAssets("t:UniversalRenderPipelineAsset");
        if (guids.Length == 0)
        {
            Debug.LogError("[DesktopOverlaySetup] URP Asset 을 찾지 못했습니다.");
            return;
        }

        foreach (var guid in guids)
        {
            var path = AssetDatabase.GUIDToAssetPath(guid);
            var asset = AssetDatabase.LoadAssetAtPath<ScriptableObject>(path);
            if (asset == null) continue;

            var so = new SerializedObject(asset);
            bool changed = false;

            changed |= SetValue(so, "m_SupportsHDR", 0);                 // 알파 있는 R8G8B8A8 로
            changed |= SetValue(so, "m_AllowPostProcessAlphaOutput", 1); // Alpha Processing 켜기
            changed |= SetValue(so, "m_HDRColorBufferPrecision", 1);     // HDR 쓸 경우 대비: 64bit(알파 있음)

            if (changed)
            {
                so.ApplyModifiedProperties();
                EditorUtility.SetDirty(asset);
                Debug.Log($"[DesktopOverlaySetup] 수정됨: {path}");
            }
        }

        AssetDatabase.SaveAssets();
        Debug.Log("[DesktopOverlaySetup] URP 알파 설정 완료. 다시 빌드하세요.");
    }

    /// <summary>
    /// 런타임 CreatePrimitive 는 빌드에서 Built-in 기본 머티리얼을 잡아 분홍색이 된다.
    /// 에디터에서 URP 머티리얼을 가진 큐브를 씬에 넣어 빌드 포함을 보장한다.
    /// </summary>
    [MenuItem("Tools/Desktop Overlay/4. Add Test Cube To Scene")]
    public static void AddTestCube()
    {
        var existing = GameObject.Find("AlphaTestCube");
        if (existing != null) Object.DestroyImmediate(existing);

        var shader = Shader.Find("Universal Render Pipeline/Lit")
                     ?? Shader.Find("Universal Render Pipeline/Unlit");
        if (shader == null)
        {
            Debug.LogError("[DesktopOverlaySetup] URP 셰이더를 찾지 못했습니다.");
            return;
        }

        var cube = GameObject.CreatePrimitive(PrimitiveType.Cube);
        cube.name = "AlphaTestCube";

        var cam = Camera.main;
        cube.transform.position = cam != null
            ? cam.transform.position + cam.transform.forward * 5f
            : new Vector3(0f, 1f, 0f);

        const string matPath = "Assets/99_Settings/AlphaTestCubeMat.mat";
        var mat = new Material(shader) { color = new Color(0.2f, 0.8f, 1f) };
        AssetDatabase.CreateAsset(mat, matPath);
        cube.GetComponent<Renderer>().sharedMaterial =
            AssetDatabase.LoadAssetAtPath<Material>(matPath);

        EditorSceneManager.MarkSceneDirty(cube.scene);
        AssetDatabase.SaveAssets();
        Debug.Log("[DesktopOverlaySetup] AlphaTestCube 추가됨. 씬을 저장(Ctrl+S)하세요.");
    }

    static bool SetValue(SerializedObject so, string propName, int value)
    {
        var p = so.FindProperty(propName);
        if (p == null)
        {
            Debug.LogWarning($"[DesktopOverlaySetup] 프로퍼티 없음: {propName}");
            return false;
        }

        if (p.propertyType == SerializedPropertyType.Boolean)
        {
            if (p.boolValue == (value != 0)) return false;
            p.boolValue = value != 0;
        }
        else
        {
            if (p.intValue == value) return false;
            p.intValue = value;
        }
        return true;
    }
}