Update: Text Channel Stuff

Bugs: Files don't work
Bugs: Video In-Line don't work

Added: idk, everything?
This commit is contained in:
2026-06-03 13:19:21 -04:00
parent cd2d809322
commit f819d7284e
20 changed files with 3447 additions and 908 deletions

View File

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using System.Net.Http;
using System.Text.RegularExpressions;
namespace RelayClient.Helpers;
/// <summary>
/// Detects URLs in message text and builds embed views:
/// • Direct image URLs → inline Image (loaded lazily from URI or base64).
/// • relay:// jump links → tappable "Jump to message" card.
/// • Everything else → a link card with an async OG-tag preview loaded in the background.
/// </summary>
public static class EmbedHelper
{
private static readonly Regex UrlPattern = new(
@"https?://[^\s<>""]+",
RegexOptions.Compiled | RegexOptions.IgnoreCase);
private static readonly Regex RelayJumpPattern = new(
@"relay://jump/([^/]+)/(.+)",
RegexOptions.Compiled | RegexOptions.IgnoreCase);
private static readonly HashSet<string> ImageExtensions =
[".jpg", ".jpeg", ".png", ".gif", ".webp", ".bmp", ".avif"];
public static List<string> DetectUrls(string text)
{
if (string.IsNullOrWhiteSpace(text)) return [];
return UrlPattern.Matches(text).Select(m => m.Value).Distinct().ToList();
}
public static List<View> BuildEmbeds(string text)
{
var views = new List<View>();
foreach (var url in DetectUrls(text))
{
try
{
if (RelayJumpPattern.IsMatch(url))
views.Add(BuildJumpCard(url));
else if (TryGetYouTubeId(url, out var ytId))
views.Add(BuildYouTubeCard(url, ytId));
else if (TryGetVimeoId(url, out var vimeoId))
views.Add(BuildVimeoCard(url, vimeoId));
else if (IsImageUrl(url))
views.Add(BuildImageEmbed(url));
else
views.Add(BuildLinkCard(url));
}
catch { /* never crash the UI */ }
}
return views;
}
public static View BuildBase64ImageEmbed(string base64, string fileName)
{
try
{
var bytes = Convert.FromBase64String(base64);
var source = ImageSource.FromStream(() => new MemoryStream(bytes));
var image = new Image
{
Source = source,
Aspect = Aspect.AspectFit,
WidthRequest = 400,
MaximumHeightRequest = 300,
HorizontalOptions = LayoutOptions.Start
};
return new Border
{
StrokeThickness = 1,
Padding = new Thickness(4),
Margin = new Thickness(0, 4, 0, 0),
Content = image
};
}
catch
{
return new Label
{
Text = $"⚠ Could not render image: {fileName}",
FontSize = 12,
TextColor = Colors.Gray
};
}
}
public static View BuildFileCard(string base64, string fileName, string mimeType)
{
var label = new Label
{
Text = $"📎 {fileName}",
FontSize = 13,
TextColor = Color.FromArgb("#5DA8FF"),
TextDecorations = TextDecorations.Underline
};
var tap = new TapGestureRecognizer();
tap.Tapped += async (_, _) =>
{
try
{
var bytes = Convert.FromBase64String(base64);
var tempPath = Path.Combine(Path.GetTempPath(), fileName);
await File.WriteAllBytesAsync(tempPath, bytes);
await Launcher.OpenAsync(new OpenFileRequest
{
File = new ReadOnlyFile(tempPath)
});
}
catch { /* ignore launch errors */ }
};
label.GestureRecognizers.Add(tap);
return new Border
{
StrokeThickness = 1,
Padding = new Thickness(8, 6),
Margin = new Thickness(0, 4, 0, 0),
Content = label
};
}
private static View BuildImageEmbed(string url)
{
var image = new Image
{
Source = ImageSource.FromUri(new Uri(url)),
Aspect = Aspect.AspectFit,
WidthRequest = 400,
MaximumHeightRequest = 300,
HorizontalOptions = LayoutOptions.Start
};
var tap = new TapGestureRecognizer();
tap.Tapped += (_, _) => _ = Launcher.OpenAsync(new Uri(url));
image.GestureRecognizers.Add(tap);
return new Border
{
StrokeThickness = 1,
Padding = new Thickness(4),
Margin = new Thickness(0, 4, 0, 0),
Content = image
};
}
private static View BuildJumpCard(string relayUrl)
{
var label = new Label
{
Text = "💬 Jump to linked message",
FontSize = 12,
TextColor = Color.FromArgb("#9ECEFF"),
TextDecorations = TextDecorations.Underline
};
label.SetValue(JumpUrlProperty, relayUrl);
return new Border
{
StrokeThickness = 1,
Padding = new Thickness(8, 4),
Margin = new Thickness(0, 4, 0, 0),
Content = label
};
}
public static readonly BindableProperty JumpUrlProperty =
BindableProperty.CreateAttached("JumpUrl", typeof(string), typeof(EmbedHelper), null);
private static View BuildLinkCard(string url)
{
var displayUrl = url.Length > 55 ? url[..52] + "…" : url;
var card = new VerticalStackLayout { Spacing = 4 };
var urlLabel = new Label
{
Text = "🔗 " + displayUrl,
FontSize = 12,
TextColor = Color.FromArgb("#5DA8FF"),
TextDecorations = TextDecorations.Underline,
LineBreakMode = LineBreakMode.TailTruncation
};
var tapUrl = new TapGestureRecognizer();
tapUrl.Tapped += (_, _) => _ = Launcher.OpenAsync(new Uri(url));
urlLabel.GestureRecognizers.Add(tapUrl);
card.Children.Add(urlLabel);
_ = Task.Run(async () =>
{
var og = await FetchOgTagsAsync(url);
if (og is null) return;
MainThread.BeginInvokeOnMainThread(() =>
{
if (!string.IsNullOrWhiteSpace(og.Title))
{
card.Children.Add(new Label
{
Text = og.Title,
FontSize = 13,
FontAttributes = FontAttributes.Bold,
MaxLines = 2,
LineBreakMode = LineBreakMode.TailTruncation
});
}
if (!string.IsNullOrWhiteSpace(og.Description))
{
card.Children.Add(new Label
{
Text = og.Description,
FontSize = 11,
TextColor = Colors.LightGray,
MaxLines = 3,
LineBreakMode = LineBreakMode.TailTruncation
});
}
if (!string.IsNullOrWhiteSpace(og.ImageUrl) && IsImageUrl(og.ImageUrl))
{
card.Children.Add(new Image
{
Source = ImageSource.FromUri(new Uri(og.ImageUrl)),
Aspect = Aspect.AspectFit,
WidthRequest = 360,
MaximumHeightRequest = 200,
HorizontalOptions = LayoutOptions.Start
});
}
});
});
return new Border
{
StrokeThickness = 1,
Padding = new Thickness(8, 6),
Margin = new Thickness(0, 4, 0, 0),
Content = card
};
}
private sealed record OgData(string? Title, string? Description, string? ImageUrl);
private static async Task<OgData?> FetchOgTagsAsync(string url)
{
try
{
using var client = new HttpClient { Timeout = TimeSpan.FromSeconds(4) };
client.DefaultRequestHeaders.Add("User-Agent", "Relay/1.0 (link preview)");
var html = await client.GetStringAsync(url);
var title = GetMetaContent(html, "og:title")
?? GetTitleTag(html);
var description = GetMetaContent(html, "og:description");
var image = GetMetaContent(html, "og:image");
if (title is null && description is null && image is null) return null;
return new OgData(title, description, image);
}
catch { return null; }
}
private static string? GetMetaContent(string html, string property)
{
var pattern = $"""<meta[^>]+property=["']{Regex.Escape(property)}["'][^>]+content=["']([^"']+)["']""";
var m = Regex.Match(html, pattern, RegexOptions.IgnoreCase);
if (m.Success) return System.Net.WebUtility.HtmlDecode(m.Groups[1].Value.Trim());
var pattern2 = $"""<meta[^>]+content=["']([^"']+)["'][^>]+property=["']{Regex.Escape(property)}["']""";
m = Regex.Match(html, pattern2, RegexOptions.IgnoreCase);
return m.Success ? System.Net.WebUtility.HtmlDecode(m.Groups[1].Value.Trim()) : null;
}
private static string? GetTitleTag(string html)
{
var m = Regex.Match(html, @"<title[^>]*>([^<]+)</title>", RegexOptions.IgnoreCase);
return m.Success ? System.Net.WebUtility.HtmlDecode(m.Groups[1].Value.Trim()) : null;
}
private static bool IsImageUrl(string url)
{
try
{
var path = new Uri(url).AbsolutePath;
var ext = Path.GetExtension(path).ToLowerInvariant();
return ImageExtensions.Contains(ext);
}
catch { return false; }
}
private static readonly Regex YouTubePattern = new(
@"(?:youtube\.com/(?:watch\?(?:.*&)?v=|embed/|shorts/|v/)|youtu\.be/)([A-Za-z0-9_-]{6,})",
RegexOptions.Compiled | RegexOptions.IgnoreCase);
private static bool TryGetYouTubeId(string url, out string id)
{
var match = YouTubePattern.Match(url);
if (match.Success)
{
id = match.Groups[1].Value;
return true;
}
id = string.Empty;
return false;
}
private static readonly Regex VimeoPattern = new(
@"vimeo\.com/(?:video/|channels/[^/]+/|groups/[^/]+/videos/)?(\d{6,})",
RegexOptions.Compiled | RegexOptions.IgnoreCase);
private static bool TryGetVimeoId(string url, out string id)
{
var match = VimeoPattern.Match(url);
if (match.Success)
{
id = match.Groups[1].Value;
return true;
}
id = string.Empty;
return false;
}
private static View BuildYouTubeCard(string url, string videoId) =>
BuildVideoCardWithEmbed(
providerLabel: "🎬 YouTube",
providerColor: Color.FromArgb("#FF4444"),
externalUrl: url,
thumbnailUrl: $"https://img.youtube.com/vi/{videoId}/hqdefault.jpg",
embedUrl: $"https://www.youtube.com/embed/{videoId}?autoplay=1&rel=0");
private static View BuildVimeoCard(string url, string videoId) =>
BuildVideoCardWithEmbed(
providerLabel: "🎬 Vimeo",
providerColor: Color.FromArgb("#1AB7EA"),
externalUrl: url,
thumbnailUrl: null, // Vimeo thumbs require an API call; skip and show a black placeholder
embedUrl: $"https://player.vimeo.com/video/{videoId}?autoplay=1");
private static View BuildVideoCardWithEmbed(
string providerLabel,
Color providerColor,
string externalUrl,
string? thumbnailUrl,
string embedUrl)
{
var card = new VerticalStackLayout { Spacing = 4 };
var headerRow = new HorizontalStackLayout { Spacing = 10 };
headerRow.Children.Add(new Label
{
Text = providerLabel,
FontSize = 11,
FontAttributes = FontAttributes.Bold,
TextColor = providerColor
});
var openExternal = new Label
{
Text = "↗ Open in browser",
FontSize = 10,
TextColor = Color.FromArgb("#8E8E93"),
TextDecorations = TextDecorations.Underline
};
var openTap = new TapGestureRecognizer();
openTap.Tapped += (_, _) => _ = Launcher.OpenAsync(new Uri(externalUrl));
openExternal.GestureRecognizers.Add(openTap);
headerRow.Children.Add(openExternal);
card.Children.Add(headerRow);
var playerHost = new ContentView
{
HorizontalOptions = LayoutOptions.Start,
Content = BuildThumbnailPlaceholder(thumbnailUrl, () =>
{
// On tap → swap the placeholder for a real player.
})
};
playerHost.Content = BuildThumbnailPlaceholder(thumbnailUrl, () =>
{
playerHost.Content = BuildEmbeddedPlayer(embedUrl);
});
card.Children.Add(playerHost);
return new Border
{
StrokeThickness = 1,
Padding = new Thickness(8, 6),
Margin = new Thickness(0, 4, 0, 0),
Content = card
};
}
private static View BuildThumbnailPlaceholder(string? thumbnailUrl, Action onPlay)
{
var grid = new Grid
{
WidthRequest = 400,
HeightRequest = 225,
BackgroundColor = Colors.Black,
HorizontalOptions = LayoutOptions.Start
};
if (!string.IsNullOrWhiteSpace(thumbnailUrl))
{
grid.Children.Add(new Image
{
Source = ImageSource.FromUri(new Uri(thumbnailUrl)),
Aspect = Aspect.AspectFill
});
}
var playBadge = new Label
{
Text = "▶",
FontSize = 36,
TextColor = Colors.White,
BackgroundColor = Color.FromArgb("#CC000000"),
HorizontalTextAlignment = TextAlignment.Center,
VerticalTextAlignment = TextAlignment.Center,
WidthRequest = 64,
HeightRequest = 64,
HorizontalOptions = LayoutOptions.Center,
VerticalOptions = LayoutOptions.Center
};
grid.Children.Add(playBadge);
var tap = new TapGestureRecognizer();
tap.Tapped += (_, _) => onPlay();
grid.GestureRecognizers.Add(tap);
return grid;
}
private static View BuildEmbeddedPlayer(string embedUrl)
{
return new WebView
{
Source = embedUrl,
WidthRequest = 480,
HeightRequest = 270,
HorizontalOptions = LayoutOptions.Start
};
}
}

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using System.Text;
using System.Text.RegularExpressions;
namespace RelayClient.Helpers;
public static class MarkdownHelper
{
private static readonly Regex FencedCode =
new(@"```([A-Za-z0-9_+#-]*)\r?\n?(.*?)```", RegexOptions.Singleline | RegexOptions.Compiled);
private static readonly Color MentionText = Color.FromArgb("#9EA8FF");
private static readonly Color MentionBg = Color.FromArgb("#2D2F5C");
private static readonly Color SpoilerBg = Color.FromArgb("#1F1F23");
public static View Render(string markdown, double fontSize = 14)
{
if (string.IsNullOrEmpty(markdown))
return new Label { Text = string.Empty, FontSize = fontSize };
var stack = new VerticalStackLayout { Spacing = 2 };
var matches = FencedCode.Matches(markdown);
int cursor = 0;
foreach (Match m in matches)
{
if (m.Index > cursor)
AppendTextSegment(stack, markdown[cursor..m.Index], fontSize);
stack.Children.Add(CreateCodeBlock(m.Groups[1].Value.Trim(), m.Groups[2].Value.TrimEnd()));
cursor = m.Index + m.Length;
}
if (cursor < markdown.Length)
AppendTextSegment(stack, markdown[cursor..], fontSize);
return stack.Children.Count == 1 ? (View)stack.Children[0] : stack;
}
private static void AppendTextSegment(VerticalStackLayout stack, string segment, double fontSize)
{
var paragraphBuffer = new StringBuilder();
void FlushParagraph()
{
if (paragraphBuffer.Length == 0) return;
stack.Children.Add(CreateInlineLabel(paragraphBuffer.ToString(), fontSize));
paragraphBuffer.Clear();
}
foreach (var rawLine in segment.Split('\n'))
{
var line = rawLine.TrimEnd('\r');
if (string.IsNullOrWhiteSpace(line))
{
FlushParagraph();
continue;
}
if (line.StartsWith("### "))
{
FlushParagraph();
stack.Children.Add(CreateHeaderLabel(line[4..], fontSize + 3));
continue;
}
if (line.StartsWith("## "))
{
FlushParagraph();
stack.Children.Add(CreateHeaderLabel(line[3..], fontSize + 6));
continue;
}
if (line.StartsWith("# "))
{
FlushParagraph();
stack.Children.Add(CreateHeaderLabel(line[2..], fontSize + 10));
continue;
}
if (line.StartsWith("-# "))
{
FlushParagraph();
stack.Children.Add(CreateSubtextLabel(line[3..], fontSize - 3));
continue;
}
if (paragraphBuffer.Length > 0)
paragraphBuffer.Append('\n');
paragraphBuffer.Append(line);
}
FlushParagraph();
}
private static View CreateCodeBlock(string language, string code)
{
var label = new Label
{
FontFamily = "AnonymousProRegular",
FontSize = 12,
TextColor = Color.FromArgb("#D4D4D4"),
LineBreakMode = LineBreakMode.WordWrap
};
var spans = SyntaxHighlighter.Highlight(code, language, 12);
if (spans.Count > 0)
{
var fs = new FormattedString();
foreach (var s in spans) fs.Spans.Add(s);
label.FormattedText = fs;
}
else
{
label.Text = code;
}
var stack = new VerticalStackLayout { Spacing = 4 };
if (!string.IsNullOrWhiteSpace(language))
{
stack.Children.Add(new Label
{
Text = language.ToLowerInvariant(),
FontFamily = "AnonymousProRegular",
FontSize = 10,
TextColor = Color.FromArgb("#6A9955"),
FontAttributes = FontAttributes.Bold
});
}
stack.Children.Add(label);
return new Border
{
BackgroundColor = Color.FromArgb("#1E1E1E"),
StrokeThickness = 0,
Padding = new Thickness(10, 6),
Content = stack
};
}
private static Label CreateHeaderLabel(string text, double size)
{
var label = new Label
{
FontSize = size,
FontAttributes = FontAttributes.Bold,
LineBreakMode = LineBreakMode.WordWrap,
Margin = new Thickness(0, 4, 0, 2)
};
var fs = new FormattedString();
var spoilerSpans = new List<Span>();
ParseInline(text, fs.Spans, size, spoilerSpans);
if (fs.Spans.Count > 0) label.FormattedText = fs;
else label.Text = text;
WireSpoilerTap(label, spoilerSpans);
return label;
}
private static Label CreateSubtextLabel(string text, double size)
{
var label = new Label
{
FontSize = size,
TextColor = Color.FromArgb("#8E8E93"),
LineBreakMode = LineBreakMode.WordWrap
};
var fs = new FormattedString();
var spoilerSpans = new List<Span>();
ParseInline(text, fs.Spans, size, spoilerSpans);
if (fs.Spans.Count > 0)
{
foreach (var s in fs.Spans)
s.TextColor ??= Color.FromArgb("#8E8E93");
label.FormattedText = fs;
}
else
{
label.Text = text;
}
WireSpoilerTap(label, spoilerSpans);
return label;
}
private static Label CreateInlineLabel(string text, double fontSize)
{
var label = new Label { FontSize = fontSize, LineBreakMode = LineBreakMode.WordWrap };
var fs = new FormattedString();
var spoilerSpans = new List<Span>();
ParseInline(text, fs.Spans, fontSize, spoilerSpans);
if (fs.Spans.Count > 0) label.FormattedText = fs;
else label.Text = text;
WireSpoilerTap(label, spoilerSpans);
return label;
}
private static void WireSpoilerTap(Label label, List<Span> spoilerSpans)
{
if (spoilerSpans.Count == 0) return;
var tap = new TapGestureRecognizer();
tap.Tapped += (_, _) =>
{
foreach (var s in spoilerSpans)
{
s.BackgroundColor = Colors.Transparent;
s.TextColor = null; // fall back to default label color
}
};
label.GestureRecognizers.Add(tap);
}
private static void ParseInline(string text, IList<Span> spans, double fontSize, List<Span> spoilerSpans)
{
var plain = new StringBuilder();
int i = 0;
void Flush()
{
if (plain.Length == 0) return;
spans.Add(new Span { Text = plain.ToString(), FontSize = fontSize });
plain.Clear();
}
while (i < text.Length)
{
char c = text[i];
if (c == '|' && Peek(text, i + 1) == '|')
{
int end = text.IndexOf("||", i + 2, StringComparison.Ordinal);
if (end > i + 2)
{
Flush();
var span = new Span
{
Text = text[(i + 2)..end],
FontSize = fontSize,
BackgroundColor = SpoilerBg,
TextColor = SpoilerBg // text invisible until revealed
};
spans.Add(span);
spoilerSpans.Add(span);
i = end + 2;
continue;
}
}
if (c == '@' && i + 1 < text.Length &&
(char.IsLetter(text[i + 1]) || text[i + 1] == '_'))
{
int end = i + 1;
while (end < text.Length && (char.IsLetterOrDigit(text[end]) || text[end] == '_'))
end++;
Flush();
spans.Add(new Span
{
Text = text[i..end],
TextColor = MentionText,
BackgroundColor = MentionBg,
FontAttributes = FontAttributes.Bold,
FontSize = fontSize
});
i = end;
continue;
}
if (c == '~' && Peek(text, i + 1) == '~')
{
int end = text.IndexOf("~~", i + 2, StringComparison.Ordinal);
if (end > i + 2)
{
Flush();
spans.Add(new Span
{
Text = text[(i + 2)..end],
FontSize = fontSize,
TextDecorations = TextDecorations.Strikethrough
});
i = end + 2; continue;
}
}
if (c == '_' && Peek(text, i + 1) == '_')
{
int end = text.IndexOf("__", i + 2, StringComparison.Ordinal);
if (end > i + 2)
{
Flush();
spans.Add(new Span
{
Text = text[(i + 2)..end],
FontSize = fontSize,
TextDecorations = TextDecorations.Underline
});
i = end + 2; continue;
}
}
if (c == '*' && Peek(text, i + 1) == '*')
{
int end = text.IndexOf("**", i + 2, StringComparison.Ordinal);
if (end > i + 2)
{
Flush();
spans.Add(new Span
{
Text = text[(i + 2)..end],
FontSize = fontSize,
FontAttributes = FontAttributes.Bold
});
i = end + 2; continue;
}
}
if (c == '*' && Peek(text, i + 1) != '*')
{
int end = FindClosingSingle(text, '*', i + 1);
if (end > i + 1)
{
Flush();
spans.Add(new Span
{
Text = text[(i + 1)..end],
FontSize = fontSize,
FontAttributes = FontAttributes.Italic
});
i = end + 1; continue;
}
}
if (c == '`')
{
int end = text.IndexOf('`', i + 1);
if (end > i + 1)
{
Flush();
spans.Add(new Span
{
Text = text[(i + 1)..end],
FontFamily = "AnonymousProRegular",
FontSize = fontSize - 1,
BackgroundColor = Color.FromArgb("#2D2D2D"),
TextColor = Color.FromArgb("#CE9178")
});
i = end + 1; continue;
}
}
plain.Append(c);
i++;
}
Flush();
}
private static char Peek(string text, int index) => index < text.Length ? text[index] : '\0';
private static int FindClosingSingle(string text, char marker, int start)
{
for (int i = start; i < text.Length; i++)
if (text[i] == marker && Peek(text, i + 1) != marker)
return i;
return -1;
}
}

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using System.Text.RegularExpressions;
namespace RelayClient.Helpers;
public static class SyntaxHighlighter
{
private static readonly Color DefaultColor = Color.FromArgb("#D4D4D4");
private static readonly Color KeywordColor = Color.FromArgb("#569CD6");
private static readonly Color StringColor = Color.FromArgb("#CE9178");
private static readonly Color NumberColor = Color.FromArgb("#B5CEA8");
private static readonly Color CommentColor = Color.FromArgb("#6A9955");
private static readonly Color TypeColor = Color.FromArgb("#4EC9B0");
private static readonly Color FunctionColor = Color.FromArgb("#DCDCAA");
private static readonly Color OperatorColor = Color.FromArgb("#D4D4D4");
private static readonly Color TagColor = Color.FromArgb("#569CD6");
private static readonly Color AttrColor = Color.FromArgb("#9CDCFE");
private const string FontFamily = "AnonymousProRegular";
private static readonly Dictionary<string, string> Aliases = new(StringComparer.OrdinalIgnoreCase)
{
["cs"] = "csharp",
["c#"] = "csharp",
["js"] = "javascript",
["jsx"] = "javascript",
["ts"] = "typescript",
["tsx"] = "typescript",
["py"] = "python",
["sh"] = "bash",
["shell"] = "bash",
["zsh"] = "bash",
["htm"] = "html",
["xml"] = "html",
["yml"] = "yaml"
};
private static readonly Dictionary<string, HashSet<string>> Keywords = new(StringComparer.OrdinalIgnoreCase)
{
["csharp"] = new(StringComparer.Ordinal)
{
"abstract","as","async","await","base","bool","break","byte","case","catch","char","checked",
"class","const","continue","decimal","default","delegate","do","double","else","enum","event",
"explicit","extern","false","finally","fixed","float","for","foreach","get","goto","if",
"implicit","in","int","interface","internal","is","lock","long","namespace","new","null",
"object","operator","out","override","params","partial","private","protected","public",
"readonly","record","ref","return","sbyte","sealed","set","short","sizeof","stackalloc",
"static","string","struct","switch","this","throw","true","try","typeof","uint","ulong",
"unchecked","unsafe","ushort","using","var","virtual","void","volatile","while","yield",
"nameof","when","where","global","init","required","file","scoped","with"
},
["javascript"] = new(StringComparer.Ordinal)
{
"async","await","break","case","catch","class","const","continue","debugger","default",
"delete","do","else","enum","export","extends","false","finally","for","from","function",
"get","if","implements","import","in","instanceof","let","new","null","of","package",
"private","protected","public","return","set","static","super","switch","this","throw",
"true","try","typeof","undefined","var","void","while","with","yield"
},
["typescript"] = new(StringComparer.Ordinal)
{
"any","as","async","await","boolean","break","case","catch","class","const","continue",
"debugger","declare","default","delete","do","else","enum","export","extends","false",
"finally","for","from","function","get","if","implements","import","in","instanceof",
"interface","is","keyof","let","namespace","never","new","null","number","of","package",
"private","protected","public","readonly","return","set","static","string","super",
"switch","this","throw","true","try","type","typeof","undefined","unknown","var","void",
"while","with","yield"
},
["python"] = new(StringComparer.Ordinal)
{
"and","as","assert","async","await","break","class","continue","def","del","elif","else",
"except","False","finally","for","from","global","if","import","in","is","lambda","None",
"nonlocal","not","or","pass","raise","return","True","try","while","with","yield","self",
"cls","match","case"
},
["sql"] = new(StringComparer.OrdinalIgnoreCase)
{
"select","from","where","insert","update","delete","create","alter","drop","table","index",
"view","join","inner","outer","left","right","full","cross","on","as","group","by","order",
"having","distinct","union","all","into","values","set","null","not","and","or","in","like",
"between","is","true","false","primary","key","foreign","references","default","limit",
"offset","with","case","when","then","else","end","exists","cast","begin","commit","rollback"
},
["bash"] = new(StringComparer.Ordinal)
{
"if","then","else","elif","fi","for","in","do","done","while","until","case","esac",
"function","return","break","continue","exit","echo","printf","export","local","readonly",
"source","alias","unset","trap","set","eval","exec","shift","let","declare","typeset"
},
["json"] = new(StringComparer.Ordinal) { "true","false","null" },
["yaml"] = new(StringComparer.Ordinal) { "true","false","null","yes","no","on","off" },
["css"] = new(StringComparer.OrdinalIgnoreCase)
{
"important","inherit","initial","unset","auto","none","normal","bold","italic","center",
"left","right","top","bottom","flex","grid","block","inline","absolute","relative","fixed",
"sticky","static"
}
};
private static readonly Dictionary<string, Regex> Tokenizers = new(StringComparer.Ordinal);
static SyntaxHighlighter()
{
const RegexOptions opts = RegexOptions.Compiled | RegexOptions.Singleline;
Tokenizers["csharp"] = new Regex(
@"(?<comment>//[^\n]*|/\*.*?\*/)" +
@"|(?<string>@""(?:""""|[^""])*""|\$""(?:\\.|[^""\\])*""|""(?:\\.|[^""\\])*""|'(?:\\.|[^'\\])*')" +
@"|(?<number>\b\d+(?:\.\d+)?[fFdDmMuUlL]*\b)" +
@"|(?<word>[A-Za-z_]\w*)",
opts);
Tokenizers["javascript"] = new Regex(
@"(?<comment>//[^\n]*|/\*.*?\*/)" +
@"|(?<string>""(?:\\.|[^""\\])*""|'(?:\\.|[^'\\])*'|`(?:\\.|[^`\\])*`)" +
@"|(?<number>\b\d+(?:\.\d+)?\b)" +
@"|(?<word>[A-Za-z_$][\w$]*)",
opts);
Tokenizers["typescript"] = Tokenizers["javascript"];
Tokenizers["python"] = new Regex(
@"(?<comment>\#[^\n]*)" +
@"|(?<string>""""""[\s\S]*?""""""|'''[\s\S]*?'''|""(?:\\.|[^""\\])*""|'(?:\\.|[^'\\])*')" +
@"|(?<number>\b\d+(?:\.\d+)?\b)" +
@"|(?<word>[A-Za-z_]\w*)",
opts);
Tokenizers["sql"] = new Regex(
@"(?<comment>--[^\n]*|/\*.*?\*/)" +
@"|(?<string>'(?:''|[^'])*')" +
@"|(?<number>\b\d+(?:\.\d+)?\b)" +
@"|(?<word>[A-Za-z_]\w*)",
opts);
Tokenizers["bash"] = new Regex(
@"(?<comment>\#[^\n]*)" +
@"|(?<string>""(?:\\.|[^""\\])*""|'[^']*')" +
@"|(?<number>\b\d+\b)" +
@"|(?<variable>\$\{?[A-Za-z_]\w*\}?)" +
@"|(?<word>[A-Za-z_][\w-]*)",
opts);
Tokenizers["json"] = new Regex(
@"(?<string>""(?:\\.|[^""\\])*"")" +
@"|(?<number>-?\b\d+(?:\.\d+)?(?:[eE][+-]?\d+)?\b)" +
@"|(?<word>true|false|null)",
opts);
Tokenizers["yaml"] = new Regex(
@"(?<comment>\#[^\n]*)" +
@"|(?<string>""(?:\\.|[^""\\])*""|'[^']*')" +
@"|(?<key>^[ \t]*[A-Za-z_][\w-]*(?=\s*:))" +
@"|(?<number>\b\d+(?:\.\d+)?\b)" +
@"|(?<word>[A-Za-z_][\w-]*)",
opts | RegexOptions.Multiline);
Tokenizers["html"] = new Regex(
@"(?<comment><!--.*?-->)" +
@"|(?<string>""[^""]*""|'[^']*')" +
@"|(?<tag></?[A-Za-z][A-Za-z0-9-]*)" +
@"|(?<attr>\b[A-Za-z_][\w-]*(?==))",
opts);
Tokenizers["css"] = new Regex(
@"(?<comment>/\*.*?\*/)" +
@"|(?<string>""[^""]*""|'[^']*')" +
@"|(?<number>-?\b\d+(?:\.\d+)?(?:px|em|rem|%|vh|vw|s|ms|deg)?\b)" +
@"|(?<selector>[.#]?[A-Za-z_][\w-]*(?=\s*[{,]))" +
@"|(?<prop>[A-Za-z-]+(?=\s*:))" +
@"|(?<word>[A-Za-z_][\w-]*)",
opts);
Tokenizers["diff"] = new Regex(
@"(?<add>^\+[^\n]*)" +
@"|(?<del>^-[^\n]*)" +
@"|(?<hunk>^@@[^\n]*)",
opts | RegexOptions.Multiline);
Tokenizers["markdown"] = new Regex(
@"(?<header>^#{1,6}[^\n]*)" +
@"|(?<bold>\*\*[^*\n]+\*\*|__[^_\n]+__)" +
@"|(?<italic>\*[^*\n]+\*|_[^_\n]+_)" +
@"|(?<code>`[^`\n]+`)" +
@"|(?<link>\[[^\]]+\]\([^)]+\))",
opts | RegexOptions.Multiline);
}
public static List<Span> Highlight(string code, string? language, double fontSize)
{
var lang = Resolve(language);
var spans = new List<Span>();
if (lang is null || !Tokenizers.TryGetValue(lang, out var tokenizer))
{
spans.Add(MakeSpan(code, DefaultColor, fontSize));
return spans;
}
var keywords = Keywords.GetValueOrDefault(lang);
int cursor = 0;
foreach (Match m in tokenizer.Matches(code))
{
if (m.Index > cursor)
spans.Add(MakeSpan(code[cursor..m.Index], DefaultColor, fontSize));
spans.Add(SpanForMatch(m, lang, keywords, fontSize));
cursor = m.Index + m.Length;
}
if (cursor < code.Length)
spans.Add(MakeSpan(code[cursor..], DefaultColor, fontSize));
return spans;
}
private static Span SpanForMatch(Match m, string lang, HashSet<string>? keywords, double fontSize)
{
if (m.Groups["comment"].Success)
return MakeSpan(m.Value, CommentColor, fontSize, italic: true);
if (m.Groups["string"].Success)
return MakeSpan(m.Value, StringColor, fontSize);
if (m.Groups["number"].Success)
return MakeSpan(m.Value, NumberColor, fontSize);
if (m.Groups["variable"].Success)
return MakeSpan(m.Value, AttrColor, fontSize);
if (m.Groups["tag"].Success)
return MakeSpan(m.Value, TagColor, fontSize);
if (m.Groups["attr"].Success)
return MakeSpan(m.Value, AttrColor, fontSize);
if (m.Groups["selector"].Success)
return MakeSpan(m.Value, TypeColor, fontSize);
if (m.Groups["prop"].Success)
return MakeSpan(m.Value, AttrColor, fontSize);
if (m.Groups["key"].Success)
return MakeSpan(m.Value, AttrColor, fontSize);
if (m.Groups["add"].Success)
return MakeSpan(m.Value, Color.FromArgb("#6A9955"), fontSize);
if (m.Groups["del"].Success)
return MakeSpan(m.Value, Color.FromArgb("#F48771"), fontSize);
if (m.Groups["hunk"].Success)
return MakeSpan(m.Value, KeywordColor, fontSize);
if (m.Groups["header"].Success)
return MakeSpan(m.Value, KeywordColor, fontSize, bold: true);
if (m.Groups["bold"].Success)
return MakeSpan(m.Value, DefaultColor, fontSize, bold: true);
if (m.Groups["italic"].Success)
return MakeSpan(m.Value, DefaultColor, fontSize, italic: true);
if (m.Groups["code"].Success)
return MakeSpan(m.Value, StringColor, fontSize);
if (m.Groups["link"].Success)
return MakeSpan(m.Value, AttrColor, fontSize);
if (m.Groups["word"].Success)
{
var word = m.Value;
var compareSet = keywords;
if (compareSet is not null && compareSet.Contains(word))
return MakeSpan(word, KeywordColor, fontSize);
if (lang is "csharp" or "javascript" or "typescript" && word.Length > 0 && char.IsUpper(word[0]))
return MakeSpan(word, TypeColor, fontSize);
return MakeSpan(word, DefaultColor, fontSize);
}
return MakeSpan(m.Value, DefaultColor, fontSize);
}
private static Span MakeSpan(string text, Color color, double fontSize, bool bold = false, bool italic = false)
{
var attrs = FontAttributes.None;
if (bold) attrs |= FontAttributes.Bold;
if (italic) attrs |= FontAttributes.Italic;
return new Span
{
Text = text,
TextColor = color,
FontSize = fontSize,
FontFamily = FontFamily,
FontAttributes = attrs
};
}
private static string? Resolve(string? language)
{
if (string.IsNullOrWhiteSpace(language)) return null;
var lower = language.Trim().ToLowerInvariant();
return Aliases.GetValueOrDefault(lower, lower);
}
}