using UnityEngine;
using UnityEngine.Rendering;
using UnityEngine.Rendering.Universal;
using UnityEngine.Rendering.RenderGraphModule;
using UnityEngine.Rendering.RenderGraphModule.Util;
using Klak.Spout;
using Klak.Ndi;
using System;
using System.Diagnostics;
using System.IO;
using Debug = UnityEngine.Debug;

// 출력 방식 열거형
public enum OutputMethod
{
    None,
    Spout,
    NDI,
    Both
}

// Normalizer 출력 디스플레이 (음수 = windowed, 0~ = borderless fullscreen monitor index)
public enum NormalizerDisplay
{
    Windowed = -1,
    Display1 = 0,
    Display2 = 1,
    Display3 = 2,
    Display4 = 3,
}

public class RenderStreamOutput : MonoBehaviour
{
    [Header("출력 설정")]
    [Tooltip("출력 방식 선택 (Spout, NDI, 또는 둘 다)")]
    public OutputMethod outputMethod = OutputMethod.Spout;
    [Tooltip("알파 채널 유지")]
    public bool keepAlpha = true;

    [Header("카메라 설정")]
    [Tooltip("렌더링 소스로 사용할 카메라")]
    public Camera MainCam;

    [Header("Spout 설정")]
    [Tooltip("Spout 송신 컴포넌트")]
    public SpoutSender Sender;
    [Tooltip("Spout 송신 이름")]
    public string spoutSenderName = "Streamingle Spout Output";

    [Header("Spout 알파 별도 송신")]
    [Tooltip("알파 전용 Spout 송신 컴포넌트 (자동 생성)")]
    public SpoutSender AlphaSender;
    [Tooltip("알파 전용 Spout 송신 이름")]
    public string alphaSpoutSenderName = "Streamingle Spout Alpha Output";
    [Tooltip("Hidden/Streamingle/AlphaOnly 셰이더")]
    public Shader alphaOnlyShader;

    [Header("NDI 설정")]
    [Tooltip("NDI 송신 컴포넌트")]
    public NdiSender NdiSender;
    [Tooltip("NDI 송신 이름")]
    public string ndiSenderName = "Streamingle NDI Output";

    [Header("텍스처 설정")]
    [Tooltip("텍스처 포맷 설정")]
    public RenderTextureFormat TextureFormat = RenderTextureFormat.DefaultHDR;
    [Tooltip("안티앨리어싱 레벨 (1, 2, 4, 8)")]
    [Range(1, 8)]
    public int AntiAliasing = 1;

    [Header("프레임 제한")]
    [Tooltip("타겟 프레임레이트 (-1: 제한 없음). VSync 는 자동으로 꺼짐")]
    public int targetFrameRate = 75;

    [Header("Spout/NDI Normalizer")]
    [Tooltip("외부 정규화 exe 자동 실행. Unity 출력의 페이싱 jitter 를 외부 프로세스로 정규화해 안정적 cadence 송신")]
    public bool normalizerEnabled = true;
    [Tooltip("출력 디스플레이 — 풀스크린 모니터 또는 Windowed")]
    public NormalizerDisplay normalizerDisplay = NormalizerDisplay.Display2;
    [Tooltip("Normalizer 출력 cadence (Hz)")]
    public float normalizerFps = 60f;
    [Tooltip("Normalizer VSync (런타임에 V 키로 토글 가능)")]
    public bool normalizerVsync = true;
    [Tooltip("Normalizer 윈도우를 항상 최상위로 유지 (런타임에 T 키로 토글 가능)")]
    public bool normalizerAlwaysOnTop = false;
    [Tooltip("Normalizer 윈도우 위에 커서가 있을 때 숨김 (런타임에 C 키로 토글 가능)")]
    public bool normalizerHideCursor = false;
    [Tooltip("⚠ 헤드리스 렌더팜 전용 — TIME_CRITICAL + Pro Audio MMCSS 스케줄링. Unity 가 foreground 일 때 켜면 Unity 자체가 starvation 됨. 평소엔 끄세요")]
    public bool normalizerRealtime = false;
    [Tooltip("Normalizer 창이 클릭으로 focus 를 가져가지 않게 함. Unity Editor 와 같이 작업할 때 권장 — 클릭이 통과되어 Unity 가 foreground 유지. 단, 런타임 핫키(F11/V/T/C/P/ESC 등) 비활성")]
    public bool normalizerNoActivate = true;

    // ──────── 내부 옵션 (사용자가 만지지 않도록 숨김) ────────
    [HideInInspector] public string normalizerExeRelativePath = "SpoutNdiNormalizer/spout_ndi_normalizer.exe";
    [HideInInspector] public string normalizerExeAbsolutePath = "";
    [HideInInspector] public int normalizerWindowWidth = 1280;
    [HideInInspector] public int normalizerWindowHeight = 720;
    [HideInInspector] public bool normalizerShowConsole = false;

    [Header("알파 합성")]
    [Tooltip("Hidden/Streamingle/AlphaCompose 셰이더")]
    public Shader alphaComposeShader;
    [Tooltip("cameraColor.a 를 알파로 사용하는 강도. NiloToon 환경에서는 cameraColor.a 가 1 로 차서 보통 0 권장")]
    [Range(0f, 4f)]
    public float sourceAlphaGain = 0.0f;
    [Tooltip("후처리(블룸/글로우 등) 가 추가한 빛을 알파로 변환하는 강도")]
    [Range(0f, 20f)]
    public float bloomAlphaGain = 5.0f;
    [Tooltip("NiloToon Prepass G 채널 알파 강도 (0 = 사용 안 함)")]
    [Range(0f, 4f)]
    public float prepassAlphaGain = 1.0f;
    [Tooltip("Prepass 알파 외곽 가우시안 블러 반경 (텍셀)")]
    [Range(0f, 5f)]
    public float alphaBlurRadius = 1.0f;

    [HideInInspector] public RenderTexture CaptureTexture = null;
    [HideInInspector] public RenderTexture AlphaOutputTexture = null;
    private RenderTexture m_PreColorTexture = null;

    private RTHandle m_CaptureHandle;
    private RTHandle m_PreColorHandle;
    private RTHandle m_AlphaOutputHandle;

    private Material m_AlphaComposeMaterial;
    private Material m_AlphaOnlyMaterial;
    private PreCapturePass m_PreCapturePass;
    private ComposePass m_ComposePass;
    private AlphaOutputPass m_AlphaOutputPass;

    private Process m_NormalizerProc;

    private int screenWidth;
    private int screenHeight;

    private OutputMethod previousOutputMethod;
    private bool previousKeepAlpha;
    private int previousTargetFrameRate;

    private static readonly int s_SourceAlphaGainID = Shader.PropertyToID("_SourceAlphaGain");
    private static readonly int s_BloomAlphaGainID = Shader.PropertyToID("_BloomAlphaGain");
    private static readonly int s_PrepassAlphaGainID = Shader.PropertyToID("_PrepassAlphaGain");
    private static readonly int s_AlphaBlurRadiusID = Shader.PropertyToID("_AlphaBlurRadius");

    private void Awake()
    {
        MainCam = MainCam == null ? Camera.main : MainCam;

        previousOutputMethod = outputMethod;
        previousKeepAlpha = keepAlpha;
        previousTargetFrameRate = targetFrameRate;

        ApplyFrameRate();
        EnsureMaterial();
        EnsureAlphaOnlyMaterial();
        InitializeOutputComponents();
        InitializeTextures();
    }

    private void Start()
    {
        if (normalizerEnabled)
        {
            try { LaunchNormalizer(); }
            catch (Exception e) { Debug.LogError($"[RenderStreamOutput] normalizer launch failed: {e}"); }
        }
    }

    private void OnApplicationQuit() { KillNormalizer(); }

    private void EnsureAlphaOnlyMaterial()
    {
        if (alphaOnlyShader == null)
            alphaOnlyShader = Shader.Find("Hidden/Streamingle/AlphaOnly");

        if (alphaOnlyShader == null)
        {
            Debug.LogError("AlphaOnly 셰이더를 찾을 수 없습니다.");
            return;
        }

        if (m_AlphaOnlyMaterial == null)
            m_AlphaOnlyMaterial = new Material(alphaOnlyShader) { hideFlags = HideFlags.HideAndDontSave };
    }

    private void ApplyFrameRate()
    {
        if (targetFrameRate > 0)
        {
            QualitySettings.vSyncCount = 0;
            Application.targetFrameRate = targetFrameRate;
        }
        else
        {
            Application.targetFrameRate = -1;
        }
    }

    private void EnsureMaterial()
    {
        if (alphaComposeShader == null)
            alphaComposeShader = Shader.Find("Hidden/Streamingle/AlphaCompose");

        if (alphaComposeShader == null)
        {
            Debug.LogError("AlphaCompose 셰이더를 찾을 수 없습니다. Always Included Shaders 에 추가하거나 인스펙터에 할당하세요.");
            return;
        }

        if (m_AlphaComposeMaterial == null)
            m_AlphaComposeMaterial = new Material(alphaComposeShader) { hideFlags = HideFlags.HideAndDontSave };

        PushMaterialParams();
    }

    private void PushMaterialParams()
    {
        if (m_AlphaComposeMaterial == null) return;
        m_AlphaComposeMaterial.SetFloat(s_SourceAlphaGainID, sourceAlphaGain);
        m_AlphaComposeMaterial.SetFloat(s_BloomAlphaGainID, bloomAlphaGain);
        m_AlphaComposeMaterial.SetFloat(s_PrepassAlphaGainID, prepassAlphaGain);
        m_AlphaComposeMaterial.SetFloat(s_AlphaBlurRadiusID, alphaBlurRadius);
    }

    private void InitializeOutputComponents()
    {
        if (outputMethod == OutputMethod.Spout || outputMethod == OutputMethod.Both)
        {
            if (Sender == null)
            {
                Sender = GetComponent<SpoutSender>();
                if (Sender == null)
                    Sender = gameObject.AddComponent<SpoutSender>();
            }
        }

        if (outputMethod == OutputMethod.NDI || outputMethod == OutputMethod.Both)
        {
            if (NdiSender == null)
            {
                NdiSender = GetComponent<NdiSender>();
                if (NdiSender == null)
                    NdiSender = gameObject.AddComponent<NdiSender>();
            }
        }

        if (AlphaSender == null)
        {
            // 같은 GameObject 에 두 번째 SpoutSender 추가
            AlphaSender = gameObject.AddComponent<SpoutSender>();
        }
    }

    private void OnEnable()
    {
        InitializeScriptablePasses();
        RenderPipelineManager.beginCameraRendering += OnBeginCameraRendering;
    }

    private void OnDisable()
    {
        RenderPipelineManager.beginCameraRendering -= OnBeginCameraRendering;
    }

    private void OnBeginCameraRendering(ScriptableRenderContext context, Camera camera)
    {
        if (camera != MainCam)
            return;

        var data = camera.GetUniversalAdditionalCameraData();
        if (m_PreCapturePass != null)
            data.scriptableRenderer.EnqueuePass(m_PreCapturePass);
        if (m_ComposePass != null)
            data.scriptableRenderer.EnqueuePass(m_ComposePass);
        if (m_AlphaOutputPass != null)
            data.scriptableRenderer.EnqueuePass(m_AlphaOutputPass);
    }

    private void InitializeTextures()
    {
        if (MainCam == null)
        {
            Debug.LogError("MainCam이 설정되지 않았습니다.");
            return;
        }

        screenWidth = MainCam.pixelWidth;
        screenHeight = MainCam.pixelHeight;

        var desc = new RenderTextureDescriptor(screenWidth, screenHeight, TextureFormat, 0)
        {
            msaaSamples = Mathf.Max(1, AntiAliasing)
        };

        ReleaseRT(ref CaptureTexture, ref m_CaptureHandle);
        CaptureTexture = new RenderTexture(desc);
        CaptureTexture.Create();
        m_CaptureHandle = RTHandles.Alloc(CaptureTexture, transferOwnership: false);

        ReleaseRT(ref m_PreColorTexture, ref m_PreColorHandle);
        m_PreColorTexture = new RenderTexture(desc);
        m_PreColorTexture.Create();
        m_PreColorHandle = RTHandles.Alloc(m_PreColorTexture, transferOwnership: false);

        ReleaseRT(ref AlphaOutputTexture, ref m_AlphaOutputHandle);
        AlphaOutputTexture = new RenderTexture(desc);
        AlphaOutputTexture.Create();
        m_AlphaOutputHandle = RTHandles.Alloc(AlphaOutputTexture, transferOwnership: false);

        UpdateOutputSources();
        InitializeScriptablePasses();
    }

    private static void ReleaseRT(ref RenderTexture rt, ref RTHandle handle)
    {
        if (handle != null)
        {
            handle.Release();
            handle = null;
        }
        if (rt != null)
        {
            rt.Release();
            DestroyImmediate(rt);
            rt = null;
        }
    }

    private void UpdateOutputSources()
    {
        if (outputMethod == OutputMethod.Spout || outputMethod == OutputMethod.Both)
        {
            if (Sender != null)
            {
                Sender.enabled = true;
                Sender.sourceTexture = CaptureTexture;
                Sender.spoutName = spoutSenderName;
                Sender.keepAlpha = keepAlpha;
                Sender.captureMethod = Klak.Spout.CaptureMethod.Texture;
            }
        }
        else if (Sender != null)
        {
            Sender.enabled = false;
        }

        if (outputMethod == OutputMethod.NDI || outputMethod == OutputMethod.Both)
        {
            if (NdiSender != null)
            {
                NdiSender.enabled = true;
                NdiSender.sourceTexture = CaptureTexture;
                NdiSender.ndiName = ndiSenderName;
                NdiSender.keepAlpha = keepAlpha;
                NdiSender.captureMethod = Klak.Ndi.CaptureMethod.Texture;
            }
            else
            {
                InitializeOutputComponents();
            }
        }
        else if (NdiSender != null)
        {
            NdiSender.enabled = false;
        }

        // 알파 전용 Spout 송신 (항상 활성)
        if (AlphaSender != null)
        {
            AlphaSender.enabled = true;
            AlphaSender.sourceTexture = AlphaOutputTexture;
            AlphaSender.spoutName = alphaSpoutSenderName;
            AlphaSender.keepAlpha = false;
            AlphaSender.captureMethod = Klak.Spout.CaptureMethod.Texture;
        }
    }

    private void InitializeScriptablePasses()
    {
        m_PreCapturePass = new PreCapturePass(m_PreColorHandle)
        {
            renderPassEvent = RenderPassEvent.BeforeRenderingPostProcessing
        };
        m_ComposePass = new ComposePass(m_CaptureHandle, m_PreColorHandle, m_PreColorTexture, m_AlphaComposeMaterial)
        {
            renderPassEvent = RenderPassEvent.AfterRenderingPostProcessing
        };
        m_AlphaOutputPass = new AlphaOutputPass(m_CaptureHandle, m_AlphaOutputHandle, m_AlphaOnlyMaterial)
        {
            renderPassEvent = RenderPassEvent.AfterRenderingPostProcessing + 1
        };
    }

    private void Update()
    {
        if (MainCam != null && (screenWidth != MainCam.pixelWidth || screenHeight != MainCam.pixelHeight))
        {
            InitializeTextures();
        }

        if (previousOutputMethod != outputMethod || previousKeepAlpha != keepAlpha)
        {
            previousOutputMethod = outputMethod;
            previousKeepAlpha = keepAlpha;
            InitializeOutputComponents();
            UpdateOutputSources();
        }

        if (previousTargetFrameRate != targetFrameRate)
        {
            previousTargetFrameRate = targetFrameRate;
            ApplyFrameRate();
        }

        PushMaterialParams();
    }

    private void OnDestroy()
    {
        m_PreCapturePass = null;
        m_ComposePass = null;
        m_AlphaOutputPass = null;

        ReleaseRT(ref CaptureTexture, ref m_CaptureHandle);
        ReleaseRT(ref m_PreColorTexture, ref m_PreColorHandle);
        ReleaseRT(ref AlphaOutputTexture, ref m_AlphaOutputHandle);

        if (m_AlphaComposeMaterial != null)
        {
            DestroyImmediate(m_AlphaComposeMaterial);
            m_AlphaComposeMaterial = null;
        }
        if (m_AlphaOnlyMaterial != null)
        {
            DestroyImmediate(m_AlphaOnlyMaterial);
            m_AlphaOnlyMaterial = null;
        }

        KillNormalizer();
    }

    // ───────────────────────── Spout/NDI Normalizer (외부 exe) ─────────────────────────

    private string ResolveNormalizerExePath()
    {
        if (!string.IsNullOrEmpty(normalizerExeAbsolutePath))
            return normalizerExeAbsolutePath;
        var rel = normalizerExeRelativePath.Replace('/', Path.DirectorySeparatorChar);
        return Path.Combine(Application.streamingAssetsPath, rel);
    }

    public void LaunchNormalizer()
    {
        var exe = ResolveNormalizerExePath();
        if (!File.Exists(exe))
        {
            Debug.LogError($"[RenderStreamOutput] normalizer exe not found: {exe}");
            return;
        }

        // 기존 자식 프로세스 + orphan 모두 종료 후 새로 실행 (단일 인스턴스 보장)
        KillNormalizer();
        KillExternalNormalizers(exe);

        var args = BuildNormalizerArgs();
        var psi = new ProcessStartInfo(exe, args)
        {
            UseShellExecute = false,
            CreateNoWindow = !normalizerShowConsole,
            WindowStyle = normalizerShowConsole ? ProcessWindowStyle.Normal : ProcessWindowStyle.Hidden,
            WorkingDirectory = Path.GetDirectoryName(exe),
        };

        m_NormalizerProc = Process.Start(psi);
        if (m_NormalizerProc == null)
        {
            Debug.LogError("[RenderStreamOutput] normalizer Process.Start returned null");
            return;
        }
        Debug.Log($"[RenderStreamOutput] normalizer launched PID {m_NormalizerProc.Id}\n  exe={exe}\n  args={args}");
    }

    public void KillNormalizer()
    {
        try
        {
            if (m_NormalizerProc != null && !m_NormalizerProc.HasExited)
            {
                m_NormalizerProc.Kill();
                m_NormalizerProc.WaitForExit(2000);
            }
        }
        catch (Exception e) { Debug.LogWarning($"[RenderStreamOutput] normalizer kill: {e.Message}"); }
        m_NormalizerProc = null;
    }

    private string BuildNormalizerArgs()
    {
        string Q(string s) => "\"" + s.Replace("\"", "\\\"") + "\"";

        var parts = new System.Collections.Generic.List<string>
        {
            "--sender", Q(spoutSenderName),
            "--fps", normalizerFps.ToString("0.###", System.Globalization.CultureInfo.InvariantCulture),
            "--width", normalizerWindowWidth.ToString(),
            "--height", normalizerWindowHeight.ToString(),
            "--parent-pid", Process.GetCurrentProcess().Id.ToString(),
        };
        int monitorIndex = (int)normalizerDisplay;
        if (monitorIndex >= 0) { parts.Add("--monitor"); parts.Add(monitorIndex.ToString()); }
        if (!normalizerVsync) parts.Add("--no-vsync");
        if (normalizerAlwaysOnTop) parts.Add("--topmost");
        if (normalizerHideCursor) parts.Add("--hide-cursor");
        if (normalizerRealtime) parts.Add("--realtime");
        if (normalizerNoActivate) parts.Add("--no-activate");
        return string.Join(" ", parts);
    }

    private static void KillExternalNormalizers(string exePath)
    {
        var name = Path.GetFileNameWithoutExtension(exePath);
        try
        {
            foreach (var p in Process.GetProcessesByName(name))
            {
                try
                {
                    if (!p.HasExited)
                    {
                        p.Kill();
                        p.WaitForExit(2000);
                        Debug.Log($"[RenderStreamOutput] killed orphan normalizer PID {p.Id}");
                    }
                }
                catch (Exception e) { Debug.LogWarning($"[RenderStreamOutput] kill orphan: {e.Message}"); }
                finally { p.Dispose(); }
            }
        }
        catch { /* best effort */ }
    }
}

// 후처리 전 cameraColor 를 PreColorTexture 로 백업
public class PreCapturePass : ScriptableRenderPass
{
    private RTHandle m_PreColorHandle;

    public PreCapturePass(RTHandle preColorHandle)
    {
        m_PreColorHandle = preColorHandle;
    }

    public override void RecordRenderGraph(RenderGraph renderGraph, ContextContainer frameData)
    {
        if (m_PreColorHandle == null)
            return;

        var resourceData = frameData.Get<UniversalResourceData>();
        if (resourceData == null)
            return;

        TextureHandle source = resourceData.activeColorTexture;
        if (!source.IsValid())
            return;

        TextureHandle destination = renderGraph.ImportTexture(m_PreColorHandle);
        using (var builder = renderGraph.AddBlitPass(source, destination, Vector2.one, Vector2.zero,
            passName: "Streamingle Pre-PostProcess Capture", returnBuilder: true))
        {
            builder.AllowPassCulling(false);
        }
    }
}

// CaptureTexture 의 알파를 그레이스케일 RGB 로 변환해서 AlphaOutputTexture 로 출력
public class AlphaOutputPass : ScriptableRenderPass
{
    private RTHandle m_SourceHandle;
    private RTHandle m_DestHandle;
    private Material m_Material;

    public AlphaOutputPass(RTHandle sourceHandle, RTHandle destHandle, Material material)
    {
        m_SourceHandle = sourceHandle;
        m_DestHandle = destHandle;
        m_Material = material;
    }

    public override void RecordRenderGraph(RenderGraph renderGraph, ContextContainer frameData)
    {
        if (m_SourceHandle == null || m_DestHandle == null || m_Material == null)
            return;

        TextureHandle source = renderGraph.ImportTexture(m_SourceHandle);
        TextureHandle destination = renderGraph.ImportTexture(m_DestHandle);

        var blitParams = new RenderGraphUtils.BlitMaterialParameters(source, destination, m_Material, 0);
        using (var builder = renderGraph.AddBlitPass(blitParams,
            passName: "Streamingle Alpha-Only Output", returnBuilder: true))
        {
            builder.AllowPassCulling(false);
        }
    }
}

// 후처리 후 cameraColor + PreColorTexture + NiloToonPrepass.g 합성 → CaptureTexture
public class ComposePass : ScriptableRenderPass
{
    private RTHandle m_CaptureHandle;
    private RTHandle m_PreColorHandle;
    private RenderTexture m_PreColorRT;
    private Material m_Material;
    private static readonly int s_PreColorTexID = Shader.PropertyToID("_PreColorTex");

    public ComposePass(RTHandle captureHandle, RTHandle preColorHandle, RenderTexture preColorRT, Material material)
    {
        m_CaptureHandle = captureHandle;
        m_PreColorHandle = preColorHandle;
        m_PreColorRT = preColorRT;
        m_Material = material;
    }

    public override void RecordRenderGraph(RenderGraph renderGraph, ContextContainer frameData)
    {
        if (m_CaptureHandle == null || m_PreColorHandle == null || m_Material == null)
            return;

        var resourceData = frameData.Get<UniversalResourceData>();
        if (resourceData == null)
            return;

        TextureHandle source = resourceData.activeColorTexture;
        if (!source.IsValid())
            return;

        TextureHandle destination = renderGraph.ImportTexture(m_CaptureHandle);
        TextureHandle preColor = renderGraph.ImportTexture(m_PreColorHandle);

        // 머티리얼에 PreColor 텍스처 직접 바인딩 (외부 RT 라 lifetime 안전).
        // RenderGraph 는 UseTexture 로 PreCapturePass→ComposePass 순서만 보장.
        m_Material.SetTexture(s_PreColorTexID, m_PreColorRT);

        var blitParams = new RenderGraphUtils.BlitMaterialParameters(source, destination, m_Material, 0);
        using (var builder = renderGraph.AddBlitPass(blitParams,
            passName: "Streamingle Alpha Compose", returnBuilder: true))
        {
            builder.UseTexture(preColor);
            builder.AllowPassCulling(false);
        }
    }
}