using System.Globalization;
using System.IO;
using System.Text;
using AmiReel.Models;

namespace AmiReel.Services;

/// <summary>
/// Renders a vertical (1080x1920, 50 FPS) YouTube Short from an existing video, with a chosen
/// visual style and title-card text overlays. A C# port of amigadb-short-fx-v4.sh so end users
/// don't need bash/WSL — the FFmpeg filtergraphs below are copied from that script.
/// </summary>
public sealed class ShortsPipeline
{
    internal const string DefaultSourceCropFilter = SourceCropFilters.CenterFourByThreeFilter;

    private readonly ProcessRunner _runner = new();

    public async Task RenderAsync(ShortSettings settings, IProgress<RenderProgress> progress, Action<string> log, CancellationToken token)
    {
        Validate(settings);
        ToolPaths tools = await ToolExtractor.ResolveAsync(settings.FfmpegPath, settings.FfprobePath, token);

        if (settings.Style == ShortStyle.Spectrum)
        {
            MediaProbe probe = new(_runner, log);
            bool hasAudio = await probe.HasAudioAsync(tools, settings.InputFile, token);
            if (!hasAudio)
                throw new InvalidOperationException("The spectrum style requires an audio stream in the source video.");
        }

        string? outputDirectory = Path.GetDirectoryName(Path.GetFullPath(settings.OutputPath));
        if (!string.IsNullOrEmpty(outputDirectory))
            Directory.CreateDirectory(outputDirectory);

        string workDir = Path.Combine(Path.GetTempPath(), "AmiReel", "shorts", Guid.NewGuid().ToString("N"));
        Directory.CreateDirectory(workDir);

        try
        {
            string hookFile = WriteTextFile(workDir, "hook.txt", settings.Hook);
            string titleFile = WriteTextFile(workDir, "title.txt", settings.Title);
            string metaFile = WriteTextFile(workDir, "meta.txt", BuildMeta(settings));
            string websiteFile = WriteTextFile(workDir, "website.txt", settings.Website);

            double duration = settings.DurationSeconds;
            double infoStart = Math.Max(0, duration - 7);
            double ctaStart = Math.Max(0, duration - 3.5);
            double hookEnd = Math.Min(2.7, duration);
            double fadeIn = Math.Clamp(settings.SourceFadeInSeconds, 0, duration);

            string baseFilter = await ResolveBaseFilterAsync(tools, settings, log, token);
            string filterComplex = BuildFilterComplex(
                ApplySourceFade(baseFilter, fadeIn),
                fontEsc: EscapeFfmpegPath(settings.FontFile),
                hookEsc: EscapeFfmpegPath(hookFile),
                titleEsc: EscapeFfmpegPath(titleFile),
                metaEsc: EscapeFfmpegPath(metaFile),
                websiteEsc: EscapeFfmpegPath(websiteFile),
                hookEnd, infoStart, ctaStart);

            List<string> args = BuildInputArguments(settings, duration);

            args.AddRange([
                "-filter_complex", filterComplex,
                "-map", "[vout]",
                "-map", "0:a?",
                "-c:v", "libx264",
                "-preset", settings.Preset,
                "-crf", settings.Crf.ToString(CultureInfo.InvariantCulture),
                "-profile:v", "high",
                "-level:v", "4.2",
                "-pix_fmt", "yuv420p",
                "-c:a", "aac",
                "-b:a", "320k",
                "-ar", "48000",
                "-movflags", "+faststart",
                "-t", F(duration),
                "-shortest",
                settings.OutputPath,
            ]);

            progress.Report(new(2, "Rendering short", $"Applying the '{settings.Style}' style"));
            TimeSpan totalSpan = TimeSpan.FromSeconds(duration);
            await _runner.RunAsync(tools.Ffmpeg, args, log, null, token, outputHandler: output =>
            {
                if (output.Time is not { } time) return;
                double percent = Math.Min(98, 2 + time.TotalSeconds / duration * 96);
                progress.Report(new(percent, "Rendering short", $"{time:hh\\:mm\\:ss} / {totalSpan:hh\\:mm\\:ss}"));
            });

            progress.Report(new(100, "Complete", settings.OutputPath));
        }
        finally
        {
            try { Directory.Delete(workDir, true); } catch { }
        }
    }

    /// <summary>
    /// Renders two 9:16 stills with the same filtergraph as the final Short: opening hook and closing title card.
    /// </summary>
    public async Task<ShortPreviewFrames> RenderPreviewAsync(
        ShortSettings settings, string outputDirectory, Action<string> log, CancellationToken token)
    {
        ValidatePreview(settings);
        ToolPaths tools = await ToolExtractor.ResolveAsync(settings.FfmpegPath, settings.FfprobePath, token);
        Directory.CreateDirectory(outputDirectory);

        string workDir = Path.Combine(outputDirectory, "meta");
        Directory.CreateDirectory(workDir);

        string hookFile = WriteTextFile(workDir, "hook.txt", string.IsNullOrWhiteSpace(settings.Hook) ? "THIS RAN ON AN AMIGA" : settings.Hook);
        string titleFile = WriteTextFile(workDir, "title.txt", string.IsNullOrWhiteSpace(settings.Title) ? "TITLE" : settings.Title);
        string metaFile = WriteTextFile(workDir, "meta.txt", BuildMeta(settings));
        string websiteFile = WriteTextFile(workDir, "website.txt", string.IsNullOrWhiteSpace(settings.Website) ? "AMIGADB.NET" : settings.Website);

        log("Resolving preview look...");
        string baseFilter = await ResolveBaseFilterAsync(tools, settings, log, token);
        bool includeText = !string.IsNullOrWhiteSpace(settings.FontFile) && File.Exists(settings.FontFile);

        string openingPath = Path.Combine(outputDirectory, "opening.png");
        string closingPath = Path.Combine(outputDirectory, "closing.png");
        await RenderPreviewStillAsync(
            tools, settings, baseFilter, includeText,
            hookFile, titleFile, metaFile, websiteFile,
            ShortPreviewShot.Opening, openingPath, log, token);
        await RenderPreviewStillAsync(
            tools, settings, baseFilter, includeText,
            hookFile, titleFile, metaFile, websiteFile,
            ShortPreviewShot.Closing, closingPath, log, token);

        return new ShortPreviewFrames(openingPath, closingPath);
    }

    /// <summary>Writes one source frame (no style filters) so the crop editor can show the raw clip.</summary>
    public async Task ExtractSourceFrameAsync(
        string inputFile,
        string start,
        string ffmpegPath,
        string ffprobePath,
        string outputPath,
        Action<string> log,
        CancellationToken token)
    {
        if (string.IsNullOrWhiteSpace(inputFile) || !File.Exists(inputFile))
            throw new FileNotFoundException("Select a valid source video for the Short.");

        string? directory = Path.GetDirectoryName(Path.GetFullPath(outputPath));
        if (!string.IsNullOrEmpty(directory))
            Directory.CreateDirectory(directory);

        ToolPaths tools = await ToolExtractor.ResolveAsync(ffmpegPath, ffprobePath, token);
        await _runner.RunAsync(tools.Ffmpeg, BuildExtractFrameArguments(inputFile, start, outputPath), log, null, token);
    }

    /// <summary>Writes several raw source frames across the clip so the crop editor can switch stills.</summary>
    public async Task<IReadOnlyList<string>> ExtractSourceFramesAsync(
        string inputFile,
        string start,
        IReadOnlyList<double> offsetsSeconds,
        string ffmpegPath,
        string ffprobePath,
        string outputDirectory,
        Action<string> log,
        CancellationToken token)
    {
        if (string.IsNullOrWhiteSpace(inputFile) || !File.Exists(inputFile))
            throw new FileNotFoundException("Select a valid source video for the Short.");
        if (offsetsSeconds.Count == 0)
            throw new ArgumentException("At least one preview offset is required.");

        Directory.CreateDirectory(outputDirectory);
        ToolPaths tools = await ToolExtractor.ResolveAsync(ffmpegPath, ffprobePath, token);
        List<string> paths = [];
        for (int index = 0; index < offsetsSeconds.Count; index++)
        {
            string seek = AddTimestampOffset(start, offsetsSeconds[index]);
            string path = Path.Combine(outputDirectory, $"frame-{index:00}.png");
            log($"Extracting crop preview {index + 1} of {offsetsSeconds.Count} ({seek})...");
            await _runner.RunAsync(tools.Ffmpeg, BuildExtractFrameArguments(inputFile, seek, path), log, null, token);
            paths.Add(path);
        }

        return paths;
    }

    internal const int CropPreviewFrameCount = 6;

    internal static IReadOnlyList<double> CropPreviewOffsets(double durationSeconds, int count = CropPreviewFrameCount)
    {
        if (count <= 1 || durationSeconds <= 0)
            return [0];

        double last = Math.Max(0, durationSeconds - 0.15);
        if (last <= 0)
            return [0];

        double[] offsets = new double[count];
        for (int index = 0; index < count; index++)
            offsets[index] = Math.Round(last * index / (count - 1), 3, MidpointRounding.AwayFromZero);
        return offsets;
    }

    internal static string FormatPreviewOffsetLabel(double seconds)
    {
        TimeSpan value = TimeSpan.FromSeconds(Math.Max(0, seconds));
        return value.TotalHours >= 1
            ? value.ToString(@"h\:mm\:ss", CultureInfo.InvariantCulture)
            : value.ToString(@"m\:ss", CultureInfo.InvariantCulture);
    }

    internal static List<string> BuildExtractFrameArguments(string inputFile, string start, string outputPath) =>
    [
        "-hide_banner",
        "-y",
        "-ss",
        string.IsNullOrWhiteSpace(start) ? "00:00:00" : start,
        "-i",
        inputFile,
        "-frames:v",
        "1",
        "-update",
        "1",
        outputPath,
    ];

    /// <summary>Looks for a common bold system font to pre-fill the Shorts font field with.</summary>
    public static string? FindDefaultFont()
    {
        string fontsDir = Environment.GetFolderPath(Environment.SpecialFolder.Fonts);
        foreach (string name in new[] { "segoeuib.ttf", "seguisb.ttf", "arialbd.ttf", "calibrib.ttf" })
        {
            string candidate = Path.Combine(fontsDir, name);
            if (File.Exists(candidate)) return candidate;
        }

        return null;
    }

    internal static void Validate(ShortSettings s)
    {
        ValidatePreview(s);
        if (string.IsNullOrWhiteSpace(s.Title))
            throw new ArgumentException("Enter a title.");
        if (string.IsNullOrWhiteSpace(s.OutputPath))
            throw new ArgumentException("Select an output file.");
        if (string.IsNullOrWhiteSpace(s.FontFile) || !File.Exists(s.FontFile))
            throw new FileNotFoundException("Select a bold TrueType/OpenType font file.");
    }

    internal static void ValidatePreview(ShortSettings s)
    {
        if (string.IsNullOrWhiteSpace(s.InputFile) || !File.Exists(s.InputFile))
            throw new FileNotFoundException("Select a valid source video for the Short.");
        if (s.DurationSeconds <= 0)
            throw new ArgumentException("Duration must be greater than zero.");
        if (s.Style == ShortStyle.Brand && (string.IsNullOrWhiteSpace(s.BackgroundImage) || !File.Exists(s.BackgroundImage)))
            throw new FileNotFoundException("The brand style requires a background image.");
        if (s.Style == ShortStyle.Video && (string.IsNullOrWhiteSpace(s.BackgroundVideo) || !File.Exists(s.BackgroundVideo)))
            throw new FileNotFoundException("The video style requires a background video.");
        if (s.VideoBlur < 0)
            throw new ArgumentException("Background video blur must be zero or greater.");
        if (s.VideoOpacity is < 0 or > 1)
            throw new ArgumentException("Background video opacity must be between 0.0 and 1.0.");
        if (s.CropLeft < 0 || s.CropRight < 0 || s.CropTop < 0 || s.CropBottom < 0)
            throw new ArgumentException("Manual crop values must be non-negative.");
        if (s.SourceMarginX < 0 || s.SourceMarginX >= 540)
            throw new ArgumentException("Source side margin must be between 0 and 539 pixels.");
        if (s.SourceFadeInSeconds < 0)
            throw new ArgumentException("Source fade-in must be zero or greater.");
    }

    internal static string BuildMeta(ShortSettings s)
    {
        List<string> parts = [];
        if (!string.IsNullOrWhiteSpace(s.Group)) parts.Add(s.Group.Trim());
        if (!string.IsNullOrWhiteSpace(s.Year)) parts.Add(s.Year.Trim());
        if (!string.IsNullOrWhiteSpace(s.Type)) parts.Add(s.Type.Trim());
        return string.Join(" · ", parts);
    }

    internal static string EscapeFfmpegPath(string value) =>
        value.Replace("\\", "\\\\").Replace(":", "\\:").Replace("'", "\\'");

    private static string WriteTextFile(string directory, string fileName, string content)
    {
        string path = Path.Combine(directory, fileName);
        File.WriteAllText(path, content + "\n", new UTF8Encoding(false));
        return path;
    }

    internal static string BuildFilterComplex(
        string baseFilter, string fontEsc, string hookEsc, string titleEsc, string metaEsc, string websiteEsc,
        double hookEnd, double infoStart, double ctaStart, bool includeTextOverlays = true)
    {
        if (!includeTextOverlays)
            return baseFilter + ";[base]fps=50,format=yuv420p[vout]";

        string hookEndStr = F(hookEnd);
        string infoStartStr = F(infoStart);
        string ctaStartStr = F(ctaStart);

        return baseFilter + ";" +
            "[base]" +
            $"drawbox=x=0:y=0:w=1080:h=245:color=black@0.50:t=fill:enable='between(t,0,{hookEndStr})'," +
            $"drawtext=fontfile='{fontEsc}':textfile='{hookEsc}':fontcolor=white:fontsize=70:line_spacing=10:x=(w-text_w)/2:y=70:fix_bounds=true:shadowcolor=black@0.75:shadowx=4:shadowy=4:enable='between(t,0,{hookEndStr})'," +
            $"drawbox=x=0:y=1490:w=1080:h=430:color=black@0.62:t=fill:enable='gte(t,{infoStartStr})'," +
            $"drawtext=fontfile='{fontEsc}':textfile='{titleEsc}':fontcolor=white:fontsize=62:line_spacing=8:x=(w-text_w)/2:y=1560:fix_bounds=true:shadowcolor=black@0.80:shadowx=4:shadowy=4:enable='gte(t,{infoStartStr})'," +
            $"drawtext=fontfile='{fontEsc}':textfile='{metaEsc}':fontcolor=white@0.92:fontsize=42:x=(w-text_w)/2:y=1655:fix_bounds=true:shadowcolor=black@0.80:shadowx=3:shadowy=3:enable='gte(t,{infoStartStr})'," +
            $"drawtext=fontfile='{fontEsc}':textfile='{websiteEsc}':fontcolor=0x55c8ff:fontsize=52:x=(w-text_w)/2:y=1780:fix_bounds=true:shadowcolor=black@0.85:shadowx=4:shadowy=4:enable='gte(t,{ctaStartStr})'," +
            "fps=50,format=yuv420p[vout]";
    }

    internal static List<string> BuildInputArguments(ShortSettings settings, double clipDuration, string? seek = null)
    {
        List<string> args =
        [
            "-hide_banner",
            "-y",
            "-ss",
            seek ?? settings.Start,
            "-t",
            F(clipDuration),
            "-i",
            settings.InputFile,
        ];
        if (settings.Style == ShortStyle.Brand)
            args.AddRange(["-loop", "1", "-i", settings.BackgroundImage]);
        if (settings.Style == ShortStyle.Video)
            args.AddRange(["-stream_loop", "-1", "-i", settings.BackgroundVideo]);
        return args;
    }

    internal static (double HookEnd, double InfoStart, double CtaStart) PreviewOverlayWindows(ShortPreviewShot shot, double duration)
    {
        if (shot == ShortPreviewShot.Opening)
            return (Math.Max(duration, 1), duration + 1, duration + 1);

        return (-1, 0, 0);
    }

    internal static double PreviewSeekSeconds(ShortPreviewShot shot, double duration)
    {
        if (shot == ShortPreviewShot.Opening)
            return Math.Min(1.2, Math.Max(0, duration * 0.2));

        return Math.Max(0, duration - 0.4);
    }

    internal static string AddTimestampOffset(string start, double seconds)
    {
        if (!TimeSpan.TryParse(start, CultureInfo.InvariantCulture, out TimeSpan parsed))
            parsed = TimeSpan.Zero;
        if (seconds < 0)
            seconds = 0;
        return (parsed + TimeSpan.FromSeconds(seconds)).ToString(@"hh\:mm\:ss\.fff", CultureInfo.InvariantCulture);
    }

    private static string F(double value) => value.ToString("0.###", CultureInfo.InvariantCulture);

    private async Task RenderPreviewStillAsync(
        ToolPaths tools,
        ShortSettings settings,
        string baseFilter,
        bool includeText,
        string hookFile,
        string titleFile,
        string metaFile,
        string websiteFile,
        ShortPreviewShot shot,
        string outputPath,
        Action<string> log,
        CancellationToken token)
    {
        (double hookEnd, double infoStart, double ctaStart) = PreviewOverlayWindows(shot, settings.DurationSeconds);
        string filterComplex = BuildFilterComplex(
            baseFilter,
            fontEsc: includeText ? EscapeFfmpegPath(settings.FontFile) : "",
            hookEsc: EscapeFfmpegPath(hookFile),
            titleEsc: EscapeFfmpegPath(titleFile),
            metaEsc: EscapeFfmpegPath(metaFile),
            websiteEsc: EscapeFfmpegPath(websiteFile),
            hookEnd,
            infoStart,
            ctaStart,
            includeTextOverlays: includeText);

        string seek = AddTimestampOffset(settings.Start, PreviewSeekSeconds(shot, settings.DurationSeconds));
        List<string> args = BuildInputArguments(settings, 0.12, seek);
        args.AddRange([
            "-filter_complex", filterComplex,
            "-map", "[vout]",
            "-frames:v", "1",
            "-update", "1",
            outputPath,
        ]);

        log($"Preview {shot.ToString().ToLowerInvariant()} frame...");
        await _runner.RunAsync(tools.Ffmpeg, args, log, null, token);
    }

    internal static string ApplySourceFade(string baseFilter, double fadeInSeconds)
    {
        if (fadeInSeconds <= 0)
            return baseFilter;

        return $"[0:v]format=rgba,fade=t=in:st=0:d={F(fadeInSeconds)}:alpha=1[srcfade];" +
               baseFilter.Replace("[0:v]", "[srcfade]", StringComparison.Ordinal);
    }

    internal static int SourceTargetWidth(int sourceMarginX) => 1080 - (sourceMarginX * 2);

    internal static string BuildSourceScaleFilter(int sourceMarginX) =>
        $"scale={SourceTargetWidth(sourceMarginX)}:-2:flags=lanczos";

    internal static string BuildManualCropFilter(int left, int right, int top, int bottom) =>
        SourceCropFilters.BuildManualCropFilter(left, right, top, bottom);

    internal static string BuildVideoBaseFilter(string cropFilter, string scaleFilter, double blur, double opacity)
    {
        string blurFilter = blur > 0 ? $",gblur=sigma={F(blur)}" : "";
        return
            "color=c=black:s=1080x1920:r=50[black];" +
            $"[1:v]scale=1080:1920:force_original_aspect_ratio=increase,crop=1080:1920,setsar=1{blurFilter},format=rgba,colorchannelmixer=aa={F(opacity)}[bgvideo];" +
            "[black][bgvideo]overlay=x=0:y=0:format=auto[bg];" +
            $"[0:v]{SourceCropFilters.Prefix(cropFilter, scaleFilter)},setsar=1[fg];" +
            "[bg][fg]overlay=x=(W-w)/2:y=(H-h)/2:format=auto[base]";
    }

    internal static string? SelectMostCommonCropSpec(string ffmpegOutput) =>
        SourceCropFilters.SelectMostCommonCropSpec(ffmpegOutput);

    internal static bool TryParseCropSpec(string spec, out int width, out int height, out int x, out int y) =>
        SourceCropFilters.TryParseCropSpec(spec, out width, out height, out x, out y);

    internal static bool TryBuildAutoHorizontalCrop(int detectedWidth, int detectedX, out int width, out int x) =>
        SourceCropFilters.TryBuildAutoHorizontalCrop(detectedWidth, detectedX, out width, out x);

    private async Task<string> ResolveBaseFilterAsync(
        ToolPaths tools, ShortSettings settings, Action<string> log, CancellationToken token)
    {
        if (settings.Style != ShortStyle.Video)
            return GetBaseFilter(settings.Style);

        string scaleFilter = BuildSourceScaleFilter(settings.SourceMarginX);
        string? detected = null;
        if (!SourceCropFilters.HasManualCrop(settings.CropLeft, settings.CropRight, settings.CropTop, settings.CropBottom)
            && settings.SourceCropMode == ShortSourceCropMode.Auto)
        {
            detected = await DetectHorizontalCropAsync(tools, settings, log, token);
            if (detected is null)
                log("Warning: could not auto-detect left/right source black borders; using centered 4:3 crop.");
        }
        else if (SourceCropFilters.HasManualCrop(settings.CropLeft, settings.CropRight, settings.CropTop, settings.CropBottom))
        {
            log($"Source crop: manual L={settings.CropLeft} R={settings.CropRight} T={settings.CropTop} B={settings.CropBottom}");
        }
        else if (settings.SourceCropMode == ShortSourceCropMode.None)
        {
            log("Source crop: none");
        }
        else
        {
            log("Source crop: centered 4:3");
        }

        string cropFilter = SourceCropFilters.Resolve(
            settings.SourceCropMode,
            settings.CropLeft,
            settings.CropRight,
            settings.CropTop,
            settings.CropBottom,
            detected);

        return BuildVideoBaseFilter(cropFilter, scaleFilter, settings.VideoBlur, settings.VideoOpacity);
    }

    private async Task<string?> DetectHorizontalCropAsync(
        ToolPaths tools, ShortSettings settings, Action<string> log, CancellationToken token)
    {
        double detectDuration = Math.Clamp(settings.DurationSeconds < 4 ? settings.DurationSeconds : 4, 0.5, 4);
        List<string> args = SourceCropFilters.BuildHorizontalCropDetectArguments(
            settings.InputFile, settings.Start, detectDuration);

        string output = await _runner.RunAsync(tools.Ffmpeg, args, log, null, token, allowFailure: true);
        string? filter = SourceCropFilters.TryBuildAutoHorizontalFilter(output);
        if (filter is null)
            return null;

        log($"Source crop: {filter} (auto left/right black crop)");
        return filter;
    }

    internal static string GetBaseFilter(ShortStyle style) => style switch
    {
        ShortStyle.Brand => """
            [1:v]scale=1080:1920:force_original_aspect_ratio=increase,crop=1080:1920,setsar=1[bg];
            [0:v]scale=920:700:force_original_aspect_ratio=decrease,pad=iw+16:ih+16:8:8:color=0x07111f,setsar=1,eq=contrast=1.02:saturation=1.02[fg];
            [bg]drawbox=x=65:y=505:w=950:h=730:color=black@0.22:t=fill[bg2];
            [bg2][fg]overlay=x=(W-w)/2:y=520:format=auto[base]
            """,

        ShortStyle.Pixel => """
            [0:v]split=2[bg_src][fg_src];
            [bg_src]scale=270:480:force_original_aspect_ratio=increase,crop=270:480,scale=1080:1920:flags=neighbor,eq=brightness=-0.36:saturation=1.18,gblur=sigma=2,setsar=1[bg];
            [fg_src]scale=1000:820:force_original_aspect_ratio=decrease,pad=iw+16:ih+16:8:8:color=0x55c8ff,setsar=1[fg];
            [bg][fg]overlay=x=(W-w)/2:y=(H-h)/2:format=auto,
            drawbox=x=0:y='300+20*sin(t*1.70)':w=1080:h=8:color=0x55c8ff@0.72:t=fill,
            drawbox=x=0:y='1610+18*sin(t*1.35)':w=1080:h=8:color=0xff7020@0.72:t=fill[base]
            """,

        ShortStyle.Mirror => """
            [0:v]split=4[canvas_src][fg_src][top_src][bottom_src];
            [canvas_src]scale=1080:1920:force_original_aspect_ratio=increase,crop=1080:1920,setsar=1,drawbox=x=0:y=0:w=1080:h=1920:color=0x010203:t=fill[canvas];
            [fg_src]scale=940:760:force_original_aspect_ratio=decrease,setsar=1[fg];
            [top_src]scale=1400:470:flags=lanczos,vflip,eq=brightness=-0.48:contrast=0.92:saturation=0.68,gblur=sigma=7,setsar=1,format=rgba,geq=r='r(X,Y)':g='g(X,Y)':b='b(X,Y)':a='255*0.62*(Y/H)'[top];
            [bottom_src]scale=1400:470:flags=lanczos,vflip,eq=brightness=-0.50:contrast=0.90:saturation=0.64,gblur=sigma=7,setsar=1,format=rgba,geq=r='r(X,Y)':g='g(X,Y)':b='b(X,Y)':a='255*0.58*(1-Y/H)'[bottom];
            [canvas][top]overlay=x=(W-w)/2:y=250:format=auto[tmp1];
            [tmp1][bottom]overlay=x=(W-w)/2:y=1435:format=auto[tmp2];
            [tmp2][fg]overlay=x=(W-w)/2:y=(H-h)/2:format=auto[base]
            """,

        ShortStyle.Crop => """
            [0:v]scale=1080:1920:force_original_aspect_ratio=increase,crop=1080:1920,setsar=1,eq=brightness=-0.04:saturation=1.05[base]
            """,

        ShortStyle.Workbench => """
            [0:v]split=2[canvas_src][screen_src];
            [canvas_src]scale=1080:1920:force_original_aspect_ratio=increase,crop=1080:1920,setsar=1,
            drawbox=x=0:y=0:w=1080:h=1920:color=0x090c20:t=fill,
            drawbox=x=55:y=410:w=970:h=930:color=0xc4c8d0:t=fill,
            drawbox=x=70:y=425:w=940:h=900:color=0x1b4f9c:t=fill,
            drawbox=x=70:y=425:w=940:h=74:color=0xf28c28:t=fill,
            drawbox=x=88:y=445:w=34:h=34:color=0x111111:t=fill[window];
            [screen_src]scale=960:760:force_original_aspect_ratio=decrease,pad=iw+10:ih+10:5:5:color=0xffffff,setsar=1[screen];
            [window][screen]overlay=x=(W-w)/2:y=525:format=auto[base]
            """,

        ShortStyle.Blur => """
            [0:v]split=2[bg_src][fg_src];
            [bg_src]scale=1080:1920:force_original_aspect_ratio=increase,crop=1080:1920,gblur=sigma=35,eq=brightness=-0.22:saturation=0.85,setsar=1[bg];
            [fg_src]scale=1080:900:force_original_aspect_ratio=decrease,setsar=1[fg];
            [bg][fg]overlay=x=(W-w)/2:y=(H-h)/2:format=auto[base]
            """,

        ShortStyle.Crt => """
            [0:v]split=2[bg_src][fg_src];
            [bg_src]scale=1080:1920:force_original_aspect_ratio=increase,crop=1080:1920,gblur=sigma=28,eq=brightness=-0.45:saturation=0.55,setsar=1[bg];
            [fg_src]scale=980:800:force_original_aspect_ratio=decrease,lenscorrection=k1=-0.060:k2=0.020,vignette=angle=PI/5,eq=contrast=1.08:saturation=1.10,setsar=1,
            drawgrid=width=iw:height=4:thickness=1:color=black@0.18[fg];
            [bg][fg]overlay=x=(W-w)/2:y=(H-h)/2:format=auto,
            drawbox=x=50:y='220+mod(t*340,1480)':w=980:h=4:color=white@0.08:t=fill[base]
            """,

        ShortStyle.Copper => """
            [0:v]split=2[bg_src][fg_src];
            [bg_src]scale=1080:1920:force_original_aspect_ratio=increase,crop=1080:1920,eq=brightness=-0.50:saturation=0.80,gblur=sigma=18,setsar=1,
            drawbox=x=0:y=0:w=1080:h=1920:color=0x061a5f@0.55:t=fill,
            drawbox=x=0:y='220+20*sin(t*1.00)':w=1080:h=140:color=0x123fcb@0.28:t=fill,
            drawbox=x=0:y='420+24*sin(t*1.20)':w=1080:h=100:color=0x2b8cff@0.22:t=fill,
            drawbox=x=0:y='660+16*sin(t*1.50)':w=1080:h=120:color=0x00b8ff@0.18:t=fill,
            drawbox=x=0:y='1110+22*sin(t*1.10)':w=1080:h=150:color=0xff7a1f@0.20:t=fill,
            drawbox=x=0:y='1360+18*sin(t*1.30)':w=1080:h=110:color=0xffc120@0.18:t=fill,
            drawbox=x=0:y='1660+15*sin(t*1.70)':w=1080:h=130:color=0x58d4ff@0.18:t=fill[bg];
            [fg_src]scale=1000:820:force_original_aspect_ratio=decrease,pad=iw+14:ih+14:7:7:color=0xffffff,setsar=1[fg];
            [bg][fg]overlay=x=(W-w)/2:y=(H-h)/2:format=auto[base]
            """,

        ShortStyle.Stars => """
            [0:v]split=2[bg_src][fg_src];
            [bg_src]scale=1080:1920:force_original_aspect_ratio=increase,crop=1080:1920,gblur=sigma=30,eq=brightness=-0.72:saturation=0.28,setsar=1,
            drawbox=x=0:y=0:w=1080:h=1920:color=0x05081b@0.75:t=fill,
            drawbox=x='mod(100+80*t,1080)':y='mod(80+210*t,1920)':w=3:h=3:color=white@0.95:t=fill,
            drawbox=x='mod(880-55*t,1080)':y='mod(220+170*t,1920)':w=2:h=2:color=white@0.85:t=fill,
            drawbox=x='mod(300+120*t,1080)':y='mod(520+140*t,1920)':w=3:h=3:color=0x9ad8ff@0.90:t=fill,
            drawbox=x='mod(980-75*t,1080)':y='mod(710+160*t,1920)':w=2:h=2:color=white@0.80:t=fill,
            drawbox=x='mod(420+65*t,1080)':y='mod(1040+200*t,1920)':w=4:h=4:color=0xffd46b@0.85:t=fill,
            drawbox=x='mod(750-90*t,1080)':y='mod(1280+110*t,1920)':w=2:h=2:color=white@0.88:t=fill,
            drawbox=x='mod(210+75*t,1080)':y='mod(1440+180*t,1920)':w=3:h=3:color=0x9ad8ff@0.90:t=fill,
            drawbox=x='mod(1030-60*t,1080)':y='mod(1680+140*t,1920)':w=2:h=2:color=white@0.82:t=fill,
            drawbox=x='mod(560+95*t,1080)':y='mod(260+260*t,1920)':w=2:h=2:color=white@0.92:t=fill,
            drawbox=x='mod(60+110*t,1080)':y='mod(860+120*t,1920)':w=3:h=3:color=0xffd46b@0.82:t=fill[bg];
            [fg_src]scale=1000:820:force_original_aspect_ratio=decrease,pad=iw+12:ih+12:6:6:color=0x55c8ff,setsar=1[fg];
            [bg][fg]overlay=x=(W-w)/2:y=(H-h)/2:format=auto[base]
            """,

        ShortStyle.Grid => """
            [0:v]split=2[bg_src][fg_src];
            [bg_src]scale=1080:1920:force_original_aspect_ratio=increase,crop=1080:1920,gblur=sigma=24,eq=brightness=-0.62:saturation=0.36,setsar=1,
            drawbox=x=0:y=0:w=1080:h=1920:color=0x090b17@0.72:t=fill,
            drawgrid=width=90:height=90:thickness=2:color=0x39d2ff@0.18,
            drawbox=x=0:y=0:w=1080:h=1120:color=0x050814@0.80:t=fill,
            drawbox=x=0:y=1120:w=1080:h=4:color=0xff54d9@0.70:t=fill[bg];
            [fg_src]scale=1000:820:force_original_aspect_ratio=decrease,pad=iw+14:ih+14:7:7:color=0xff54d9,setsar=1[fg];
            [bg][fg]overlay=x=(W-w)/2:y=(H-h)/2:format=auto[base]
            """,

        ShortStyle.Tiles => """
            [0:v]split=5[fg_src][a][b][c][d];
            [a]scale=540:960:force_original_aspect_ratio=increase,crop=540:960,eq=brightness=-0.45:saturation=0.68,gblur=sigma=4,setsar=1[ta];
            [b]scale=540:960:force_original_aspect_ratio=increase,crop=540:960,hflip,eq=brightness=-0.45:saturation=0.68,gblur=sigma=4,setsar=1[tb];
            [c]scale=540:960:force_original_aspect_ratio=increase,crop=540:960,vflip,eq=brightness=-0.45:saturation=0.68,gblur=sigma=4,setsar=1[tc];
            [d]scale=540:960:force_original_aspect_ratio=increase,crop=540:960,hflip,vflip,eq=brightness=-0.45:saturation=0.68,gblur=sigma=4,setsar=1[td];
            [ta][tb]hstack=inputs=2[top];
            [tc][td]hstack=inputs=2[bottom];
            [top][bottom]vstack=inputs=2[bg];
            [fg_src]scale=980:800:force_original_aspect_ratio=decrease,pad=iw+16:ih+16:8:8:color=0xffffff,setsar=1[fg];
            [bg][fg]overlay=x=(W-w)/2:y=(H-h)/2:format=auto[base]
            """,

        ShortStyle.Scan => """
            [0:v]split=2[bg_src][fg_src];
            [bg_src]scale=1080:1920:force_original_aspect_ratio=increase,crop=1080:1920,scale=360:640:flags=neighbor,scale=1080:1920:flags=neighbor,eq=brightness=-0.44:saturation=1.05,gblur=sigma=2,setsar=1[bg];
            [fg_src]scale=1000:820:force_original_aspect_ratio=decrease,pad=iw+16:ih+16:8:8:color=0x55c8ff,setsar=1[fg];
            [bg][fg]overlay=x=(W-w)/2:y=(H-h)/2:format=auto,
            drawbox=x=40:y='220+mod(t*380,1480)':w=1000:h=8:color=white@0.14:t=fill,
            drawbox=x=0:y='280+20*sin(t*1.40)':w=1080:h=6:color=0x55c8ff@0.45:t=fill,
            drawbox=x=0:y='1640+15*sin(t*1.20)':w=1080:h=6:color=0xff7020@0.45:t=fill[base]
            """,

        ShortStyle.Starfield => """
            [0:v]split=2[bg_src][fg_src];
            [bg_src]scale=1080:1920:force_original_aspect_ratio=increase,crop=1080:1920,gblur=sigma=32,eq=brightness=-0.78:saturation=0.22,setsar=1,
            drawbox=x=0:y=0:w=1080:h=1920:color=0x020511@0.82:t=fill,
            drawbox=x='mod(120+75*t,1080)':y='mod(80+520*t,1920)':w=3:h=18:color=white@0.92:t=fill,
            drawbox=x='mod(970-55*t,1080)':y='mod(250+430*t,1920)':w=2:h=14:color=0xa4dcff@0.85:t=fill,
            drawbox=x='mod(370+95*t,1080)':y='mod(430+600*t,1920)':w=4:h=24:color=white@0.90:t=fill,
            drawbox=x='mod(810-80*t,1080)':y='mod(640+470*t,1920)':w=2:h=17:color=0xffdc83@0.85:t=fill,
            drawbox=x='mod(230+65*t,1080)':y='mod(900+540*t,1920)':w=3:h=20:color=white@0.88:t=fill,
            drawbox=x='mod(1020-100*t,1080)':y='mod(1110+650*t,1920)':w=4:h=26:color=0x8fd5ff@0.90:t=fill,
            drawbox=x='mod(560+85*t,1080)':y='mod(1320+490*t,1920)':w=2:h=16:color=white@0.86:t=fill,
            drawbox=x='mod(70+110*t,1080)':y='mod(1510+590*t,1920)':w=3:h=22:color=0xffdc83@0.82:t=fill,
            drawbox=x='mod(720-60*t,1080)':y='mod(1720+450*t,1920)':w=2:h=15:color=white@0.88:t=fill,
            drawbox=x='mod(440+105*t,1080)':y='mod(180+700*t,1920)':w=3:h=28:color=0xa4dcff@0.88:t=fill,
            drawbox=x='mod(900-72*t,1080)':y='mod(780+560*t,1920)':w=2:h=18:color=white@0.84:t=fill,
            drawbox=x='mod(310+90*t,1080)':y='mod(1240+620*t,1920)':w=4:h=24:color=white@0.90:t=fill[bg];
            [fg_src]scale=1000:820:force_original_aspect_ratio=decrease,pad=iw+14:ih+14:7:7:color=0x70cfff,setsar=1[fg];
            [bg][fg]overlay=x=(W-w)/2:y=(H-h)/2:format=auto[base]
            """,

        ShortStyle.Plasma => """
            [0:v]split=2[dim_src][fg_src];
            nullsrc=size=1080x1920:rate=50,format=rgb24,
            geq=r='128+105*sin(X/68+T*1.9)+22*sin(Y/91-T*1.1)':g='128+96*sin(Y/75+T*1.5)+26*sin((X+Y)/120+T*1.3)':b='128+110*sin((X-Y)/82-T*1.7)',
            gblur=sigma=18,eq=brightness=-0.16:saturation=1.22[plasma];
            [dim_src]scale=1080:1920:force_original_aspect_ratio=increase,crop=1080:1920,gblur=sigma=26,eq=brightness=-0.70:saturation=0.35,setsar=1[dim];
            [plasma][dim]blend=all_mode=overlay:all_opacity=0.35[bg];
            [fg_src]scale=1000:820:force_original_aspect_ratio=decrease,pad=iw+16:ih+16:8:8:color=0xffffff,setsar=1[fg];
            [bg][fg]overlay=x=(W-w)/2:y=(H-h)/2:format=auto[base]
            """,

        ShortStyle.Rasterbars => """
            [0:v]split=2[bg_src][fg_src];
            [bg_src]scale=1080:1920:force_original_aspect_ratio=increase,crop=1080:1920,gblur=sigma=30,eq=brightness=-0.70:saturation=0.35,setsar=1,
            drawbox=x=0:y=0:w=1080:h=1920:color=0x05061b@0.80:t=fill,
            drawbox=x=0:y='250+90*sin(t*1.25)':w=1080:h=30:color=0xff3b7f@0.78:t=fill,
            drawbox=x=0:y='300+90*sin(t*1.25)':w=1080:h=24:color=0xff7b32@0.72:t=fill,
            drawbox=x=0:y='345+90*sin(t*1.25)':w=1080:h=18:color=0xffd12b@0.66:t=fill,
            drawbox=x=0:y='1510+85*sin(t*1.10+1.2)':w=1080:h=18:color=0x55e6ff@0.68:t=fill,
            drawbox=x=0:y='1550+85*sin(t*1.10+1.2)':w=1080:h=24:color=0x4b8cff@0.72:t=fill,
            drawbox=x=0:y='1600+85*sin(t*1.10+1.2)':w=1080:h=30:color=0x8b55ff@0.76:t=fill[bg];
            [fg_src]scale=1000:820:force_original_aspect_ratio=decrease,pad=iw+14:ih+14:7:7:color=0xffffff,setsar=1[fg];
            [bg][fg]overlay=x=(W-w)/2:y=(H-h)/2:format=auto[base]
            """,

        ShortStyle.Vhs => """
            [0:v]split=2[bg_src][fg_src];
            [bg_src]scale=1080:1920:force_original_aspect_ratio=increase,crop=1080:1920,gblur=sigma=26,eq=brightness=-0.44:saturation=0.55,noise=alls=10:allf=t+u,setsar=1[bg];
            [fg_src]scale=1000:820:force_original_aspect_ratio=decrease,chromashift=cbh=2:crh=-2,noise=alls=5:allf=t+u,eq=contrast=1.08:saturation=0.92,vignette=angle=PI/4.5,setsar=1,
            drawgrid=width=iw:height=5:thickness=1:color=black@0.13[fg];
            [bg][fg]overlay=x=(W-w)/2:y=(H-h)/2:format=auto,
            drawbox=x=0:y='300+mod(t*510,1320)':w=1080:h=10:color=white@0.08:t=fill,
            drawbox=x=0:y='420+mod(t*320,1080)':w=1080:h=3:color=0x7bd7ff@0.10:t=fill[base]
            """,

        ShortStyle.Monitor => """
            [0:v]split=2[bg_src][screen_src];
            [bg_src]scale=1080:1920:force_original_aspect_ratio=increase,crop=1080:1920,gblur=sigma=34,eq=brightness=-0.68:saturation=0.32,setsar=1,
            drawbox=x=0:y=0:w=1080:h=1920:color=0x11131a@0.78:t=fill,
            drawbox=x=42:y=365:w=996:h=1000:color=0xaaa69a:t=fill,
            drawbox=x=68:y=392:w=944:h=944:color=0x2a2926:t=fill,
            drawbox=x=105:y=438:w=870:h=790:color=0x050505:t=fill,
            drawbox=x=792:y=1260:w=44:h=18:color=0x6aff73:t=fill,
            drawbox=x=852:y=1253:w=30:h=30:color=0x232323:t=fill,
            drawbox=x=910:y=1253:w=30:h=30:color=0x232323:t=fill,
            drawbox=x=380:y=1365:w=320:h=75:color=0x8f8b80:t=fill,
            drawbox=x=290:y=1438:w=500:h=36:color=0x77736b:t=fill[monitor];
            [screen_src]scale=840:750:force_original_aspect_ratio=decrease,lenscorrection=k1=-0.045:k2=0.012,vignette=angle=PI/5,eq=contrast=1.06:saturation=1.06,setsar=1[screen];
            [monitor][screen]overlay=x=(W-w)/2:y=458:format=auto[base]
            """,

        ShortStyle.Split => """
            [0:v]split=4[bg_src][main_src][top_src][bottom_src];
            [bg_src]scale=1080:1920:force_original_aspect_ratio=increase,crop=1080:1920,gblur=sigma=34,eq=brightness=-0.55:saturation=0.55,setsar=1[bg];
            [top_src]scale=1080:520:force_original_aspect_ratio=increase,crop=1080:360:y='(ih-360)/2',eq=brightness=-0.28:saturation=0.88,gblur=sigma=2,setsar=1[top];
            [bottom_src]scale=1080:520:force_original_aspect_ratio=increase,crop=1080:360:y='(ih-360)/2',hflip,eq=brightness=-0.32:saturation=0.80,gblur=sigma=2,setsar=1[bottom];
            [main_src]scale=1000:820:force_original_aspect_ratio=decrease,pad=iw+14:ih+14:7:7:color=0xffffff,setsar=1[main];
            [bg][top]overlay=x=0:y=275[tmp1];
            [tmp1][bottom]overlay=x=0:y=1285[tmp2];
            [tmp2][main]overlay=x=(W-w)/2:y=(H-h)/2:format=auto[base]
            """,

        ShortStyle.Spectrum => """
            [0:v]split=2[bg_src][fg_src];
            [bg_src]scale=1080:1920:force_original_aspect_ratio=increase,crop=1080:1920,gblur=sigma=30,eq=brightness=-0.62:saturation=0.40,setsar=1,
            drawbox=x=0:y=0:w=1080:h=1920:color=0x040717@0.68:t=fill[bg];
            [fg_src]scale=1000:780:force_original_aspect_ratio=decrease,pad=iw+12:ih+12:6:6:color=0x55c8ff,setsar=1[fg];
            [0:a]aformat=sample_fmts=fltp:channel_layouts=stereo,showspectrum=s=1000x250:mode=combined:color=rainbow:scale=sqrt:fscale=log:slide=scroll:win_func=hann:fps=50:opacity=0.85,format=rgba[spec];
            [bg][spec]overlay=x=(W-w)/2:y=1360:format=auto[tmp];
            [tmp][fg]overlay=x=(W-w)/2:y=480:format=auto[base]
            """,

        ShortStyle.Video => BuildVideoBaseFilter(
            DefaultSourceCropFilter, BuildSourceScaleFilter(40), blur: 0, opacity: 1),

        _ => throw new ArgumentOutOfRangeException(nameof(style), style, "Unknown short style."),
    };
}