// Copyright (c) ppy Pty Ltd <[email protected]>. Licensed under the MIT Licence. // See the LICENCE file in the repository root for full licence text. using System; using System.Collections.Generic; using System.Linq; using System.Text.RegularExpressions; using System.Web; using osu.Game.Online.API.Requests.Responses; using osu.Game.Rulesets.Edit; namespace osu.Game.Online.Chat { public static class MessageFormatter { // [[Performance Points]] -> wiki:Performance Points (https://osu.ppy.sh/wiki/Performance_Points) private static readonly Regex wiki_regex = new Regex(@"\[\[(?<text>[^\]]+)\]\]"); // (test)[https://osu.ppy.sh/b/1234] -> test (https://osu.ppy.sh/b/1234) private static readonly Regex old_link_regex = new Regex(@"\((?<text>(((?<=\\)[\(\)])|[^\(\)])*(((?<open>\()(((?<=\\)[\(\)])|[^\(\)])*)+((?<close-open>\))(((?<=\\)[\(\)])|[^\(\)])*)+)*(?(open)(?!)))\)\[(?<url>[a-z]+://[^ ]+)\]"); // [https://osu.ppy.sh/b/1234 Beatmap [Hard] (poop)] -> Beatmap [hard] (poop) (https://osu.ppy.sh/b/1234) private static readonly Regex new_link_regex = new Regex(@"\[(?<url>[a-z]+://[^ ]+) (?<text>(((?<=\\)[\[\]])|[^\[\]])*(((?<open>\[)(((?<=\\)[\[\]])|[^\[\]])*)+((?<close-open>\])(((?<=\\)[\[\]])|[^\[\]])*)+)*(?(open)(?!)))\]"); // [test](https://osu.ppy.sh/b/1234) -> test (https://osu.ppy.sh/b/1234) aka correct markdown format private static readonly Regex markdown_link_regex = new Regex(@"\[(?<text>(((?<=\\)[\[\]])|[^\[\]])*(((?<open>\[)(((?<=\\)[\[\]])|[^\[\]])*)+((?<close-open>\])(((?<=\\)[\[\]])|[^\[\]])*)+)*(?(open)(?!)))\]\((?<url>[a-z]+://[^ ]+)(\s+(?<title>""([^""]|(?<=\\)"")*""))?\)"); // advanced, RFC-compatible regular expression that matches any possible URL, *but* allows certain invalid characters that are widely used // This is in the format (<required>, [optional]): // http[s]://<domain>.<tld>[:port][/path][?query][#fragment] private static readonly Regex advanced_link_regex = new Regex( // protocol @"(?<link>(https?|osu(mp)?):\/\/" + // domain + tld @"(?<domain>(?:[a-z0-9]\.|[a-z0-9][a-z0-9-]*[a-z0-9]\.)*[a-z0-9-]*[a-z0-9]" + // port (optional) @"(?::\d+)?)" + // path (optional) @"(?<path>(?:(?:\/+(?:[a-z0-9$_\.\+!\*\',;:\(\)@&~=-]|%[0-9a-f]{2})*)*" + // query (optional) @"(?:\?(?:[a-z0-9$_\+!\*\',;:\(\)@&=\/~-]|%[0-9a-f]{2})*)?)?" + // fragment (optional) @"(?:#(?:[a-z0-9$_\+!\*\',;:\(\)@&=\/~-]|%[0-9a-f]{2})*)?)?)", RegexOptions.IgnoreCase); // #osu private static readonly Regex channel_regex = new Regex(@"(#[a-zA-Z]+[a-zA-Z0-9]+)"); // Unicode emojis private static readonly Regex emoji_regex = new Regex(@"(\uD83D[\uDC00-\uDE4F])"); /// <summary> /// The root URL for the website, used for chat link matching. /// </summary> public static string WebsiteRootUrl { get => websiteRootUrl; set => websiteRootUrl = value .Trim('/') // trim potential trailing slash/ .Split('/').Last(); // only keep domain name, ignoring protocol. } private static string websiteRootUrl = "osu.ppy.sh"; private static void handleMatches(Regex regex, string display, string link, MessageFormatterResult result, int startIndex = 0, LinkAction? linkActionOverride = null, char[]? escapeChars = null) { int captureOffset = 0; foreach (Match m in regex.Matches(result.Text, startIndex)) { int index = m.Index - captureOffset; string displayText = string.Format(display, m.Groups[0], m.Groups["text"].Value, m.Groups["url"].Value).Trim(); string linkText = string.Format(link, m.Groups[0], m.Groups["text"].Value, m.Groups["url"].Value).Trim(); if (displayText.Length == 0 || linkText.Length == 0) continue; // Remove backslash escapes in front of the characters provided in escapeChars if (escapeChars != null) displayText = escapeChars.Aggregate(displayText, (current, c) => current.Replace($"\\{c}", c.ToString())); // Check for overlapping links if (!result.Links.Exists(l => l.Overlaps(index, m.Length))) { result.Text = result.Text.Remove(index, m.Length).Insert(index, displayText); // since we just changed the line display text, offset any already processed links. result.Links.ForEach(l => l.Index -= l.Index > index ? m.Length - displayText.Length : 0); var details = GetLinkDetails(linkText); result.Links.Add(new Link(linkText, index, displayText.Length, linkActionOverride ?? details.Action, details.Argument)); // adjust the offset for processing the current matches group. captureOffset += m.Length - displayText.Length; } } } private static void handleAdvanced(Regex regex, MessageFormatterResult result, int startIndex = 0) { foreach (Match m in regex.Matches(result.Text, startIndex)) { int index = m.Index; string linkText = m.Groups["link"].Value; int indexLength = linkText.Length; var details = GetLinkDetails(linkText); var link = new Link(linkText, index, indexLength, details.Action, details.Argument); // sometimes an already-processed formatted link can reduce to a simple URL, too // (example: [mean example - https://osu.ppy.sh](https://osu.ppy.sh)) // therefore we need to check if any of the pre-existing links contains the raw one we found if (result.Links.All(existingLink => !existingLink.Overlaps(link))) result.Links.Add(link); } } public static LinkDetails GetLinkDetails(string url) { string[] args = url.Split('/', StringSplitOptions.RemoveEmptyEntries); args[0] = args[0].TrimEnd(':'); switch (args[0]) { case @"http": case @"https": // length > 3 since all these links need another argument to work if (args.Length > 3 && args[1].EndsWith(WebsiteRootUrl, StringComparison.OrdinalIgnoreCase)) { string mainArg = args[3]; switch (args[2]) { // old site only case @"b": case @"beatmaps": { string trimmed = mainArg.Split('?').First(); if (int.TryParse(trimmed, out int id)) return new LinkDetails(LinkAction.OpenBeatmap, id.ToString()); break; } case @"s": case @"beatmapsets": case @"d": { if (mainArg == @"discussions") // handle discussion links externally for now return new LinkDetails(LinkAction.External, url); if (args.Length > 4 && int.TryParse(args[4], out int id)) // https://osu.ppy.sh/beatmapsets/1154158#osu/2768184 return new LinkDetails(LinkAction.OpenBeatmap, id.ToString()); // https://osu.ppy.sh/beatmapsets/1154158#whatever string trimmed = mainArg.Split('#').First(); if (int.TryParse(trimmed, out id)) return new LinkDetails(LinkAction.OpenBeatmapSet, id.ToString()); break; } case @"u": case @"users": return getUserLink(mainArg); case @"wiki": return new LinkDetails(LinkAction.OpenWiki, string.Join('/', args.Skip(3))); case @"home": if (mainArg != @"changelog") // handle link other than changelog as external for now return new LinkDetails(LinkAction.External, url); switch (args.Length) { case 4: // https://osu.ppy.sh/home/changelog return new LinkDetails(LinkAction.OpenChangelog, string.Empty); case 6: // https://osu.ppy.sh/home/changelog/lazer/2021.1006 return new LinkDetails(LinkAction.OpenChangelog, $"{args[4]}/{args[5]}"); } break; case @"multiplayer": if (mainArg != @"rooms") return new LinkDetails(LinkAction.External, url); if (args.Length == 5) { // https://osu.ppy.sh/multiplayer/rooms/{id} // route used for both multiplayer and playlists return new LinkDetails(LinkAction.JoinRoom, args[4]); } break; } } break; case @"osu": // every internal link also needs some kind of argument if (args.Length < 3) break; LinkAction linkType; switch (args[1]) { case @"chan": linkType = LinkAction.OpenChannel; break; case @"edit": linkType = LinkAction.OpenEditorTimestamp; break; case @"b": linkType = LinkAction.OpenBeatmap; break; case @"s": case @"dl": linkType = LinkAction.OpenBeatmapSet; break; case @"spectate": linkType = LinkAction.Spectate; break; case @"u": return getUserLink(args[2]); case @"room": linkType = LinkAction.JoinRoom; break; default: return new LinkDetails(LinkAction.External, url); } return new LinkDetails(linkType, HttpUtility.UrlDecode(args[2])); } return new LinkDetails(LinkAction.External, url); } private static LinkDetails getUserLink(string argument) { if (int.TryParse(argument, out int userId)) return new LinkDetails(LinkAction.OpenUserProfile, new APIUser { Id = userId }); return new LinkDetails(LinkAction.OpenUserProfile, new APIUser { Username = argument }); } private static MessageFormatterResult format(string toFormat, int startIndex = 0, int space = 3) { var result = new MessageFormatterResult(toFormat); // handle the [link display] format handleMatches(new_link_regex, "{1}", "{2}", result, startIndex, escapeChars: new[] { '[', ']' }); // handle the standard markdown []() format handleMatches(markdown_link_regex, "{1}", "{2}", result, startIndex, escapeChars: new[] { '[', ']' }); // handle the ()[] link format handleMatches(old_link_regex, "{1}", "{2}", result, startIndex, escapeChars: new[] { '(', ')' }); // handle wiki links handleMatches(wiki_regex, "{1}", $"https://{WebsiteRootUrl}/wiki/{{1}}", result, startIndex); // handle bare links handleAdvanced(advanced_link_regex, result, startIndex); // handle editor times handleMatches(EditorTimestampParser.TIME_REGEX_STRICT, "{0}", $@"{OsuGameBase.OSU_PROTOCOL}edit/{{0}}", result, startIndex, LinkAction.OpenEditorTimestamp); // handle channels handleMatches(channel_regex, "{0}", $@"{OsuGameBase.OSU_PROTOCOL}chan/{{0}}", result, startIndex, LinkAction.OpenChannel); // see: https://github.com/ppy/osu/pull/24190 result.Text = Regex.Replace(result.Text, emoji_regex.ToString(), "[emoji]"); return result; } public static Message FormatMessage(Message inputMessage) { var result = format(inputMessage.Content); inputMessage.DisplayContent = result.Text; // Sometimes, regex matches are not in order result.Links.Sort(); inputMessage.Links = result.Links; return inputMessage; } public static MessageFormatterResult FormatText(string text) { var result = format(text); result.Links.Sort(); return result; } public class MessageFormatterResult { public List<Link> Links = new List<Link>(); public string Text; public string OriginalText; public MessageFormatterResult(string text) { OriginalText = Text = text; } } } public class LinkDetails { public readonly LinkAction Action; public readonly object Argument; public LinkDetails(LinkAction action, object argument) { Action = action; Argument = argument; } } public enum LinkAction { External, OpenBeatmap, OpenBeatmapSet, OpenChannel, OpenEditorTimestamp, JoinRoom, Spectate, OpenUserProfile, SearchBeatmapSet, OpenWiki, Custom, OpenChangelog, FilterBeatmapSetGenre, FilterBeatmapSetLanguage, } public class Link : IComparable<Link> { public string Url; public int Index; public int Length; public LinkAction Action; public object Argument; public Link(string url, int startIndex, int length, LinkAction action, object argument) { Url = url; Index = startIndex; Length = length; Action = action; Argument = argument; } public bool Overlaps(Link otherLink) => Overlaps(otherLink.Index, otherLink.Length); public bool Overlaps(int otherIndex, int otherLength) => Index < otherIndex + otherLength && otherIndex < Index + Length; public int CompareTo(Link? otherLink) => Index > otherLink?.Index ? 1 : -1; } }
