Pass proper allowed_mentions when sending webhook messages

PluralKit.Bot/Handlers/MessageCreated.cs

@@ -91,7 +91,7 @@ namespace PluralKit.Bot
             // Check if message starts with the command prefix
             if (content.StartsWith("pk;", StringComparison.InvariantCultureIgnoreCase)) argPos = 3;
             else if (content.StartsWith("pk!", StringComparison.InvariantCultureIgnoreCase)) argPos = 3;
-            else if (StringUtils.HasMentionPrefix(content, ref argPos, out var id)) // Set argPos to the proper value
+            else if (DiscordUtils.HasMentionPrefix(content, ref argPos, out var id)) // Set argPos to the proper value
                 if (id != _client.CurrentUser.Id) // But undo it if it's someone else's ping
                     argPos = -1;
 

PluralKit.Bot/PluralKit.Bot.csproj

@@ -10,8 +10,8 @@
     </ItemGroup>
 
     <ItemGroup>
-      <PackageReference Include="DSharpPlus" Version="4.0.0-nightly-00707" />
+      <PackageReference Include="DSharpPlus" Version="4.0.0-nightly-00709" />
-      <PackageReference Include="DSharpPlus.Rest" Version="4.0.0-nightly-00707" />
+      <PackageReference Include="DSharpPlus.Rest" Version="4.0.0-nightly-00709" />
       <PackageReference Include="Humanizer.Core" Version="2.7.9" />
       <PackageReference Include="Sentry" Version="2.0.0-beta7" />
       <PackageReference Include="SixLabors.ImageSharp" Version="1.0.0-beta0007" />

PluralKit.Bot/Proxy/ProxyService.cs

@@ -57,8 +57,11 @@ namespace PluralKit.Bot
             if (!await CheckBotPermissionsOrError(message.Channel)) return false;
             if (!CheckProxyNameBoundsOrError(match.Member.ProxyName(ctx))) return false;
             
+            // Check if we can mention everyone/here
+            var allowEveryone = (message.Channel.PermissionsInSync(message.Author) & Permissions.MentionEveryone) != 0;
+
             // Everything's in order, we can execute the proxy!
-            await ExecuteProxy(conn, message, ctx, match);
+            await ExecuteProxy(conn, message, ctx, match, allowEveryone);
             return true;
         }
 
@@ -85,13 +88,12 @@ namespace PluralKit.Bot
         }
 
         private async Task ExecuteProxy(IPKConnection conn, DiscordMessage trigger, MessageContext ctx,
-                                        ProxyMatch match)
+                                        ProxyMatch match, bool allowEveryone)
         {
             // Send the webhook
             var id = await _webhookExecutor.ExecuteWebhook(trigger.Channel, match.Member.ProxyName(ctx),
                 match.Member.ProxyAvatar(ctx),
-                match.ProxyContent, trigger.Attachments);
+                match.ProxyContent, trigger.Attachments, allowEveryone);
-
             
             Task SaveMessage() => _data.AddMessage(conn, trigger.Author.Id, trigger.Channel.GuildId, trigger.Channel.Id, id, trigger.Id, match.Member.Id);
             Task LogMessage() => _logChannel.LogMessage(ctx, match, trigger, id).AsTask();

PluralKit.Bot/Proxy/ProxyTagParser.cs

@@ -80,7 +80,7 @@ namespace PluralKit.Bot
         private string? ExtractLeadingMention(ref string input)
         {
             var mentionPos = 0;
-            if (!StringUtils.HasMentionPrefix(input, ref mentionPos, out _)) return null;
+            if (!DiscordUtils.HasMentionPrefix(input, ref mentionPos, out _)) return null;
             
             var leadingMention = input.Substring(0, mentionPos);
             input = input.Substring(mentionPos);

PluralKit.Bot/Services/WebhookExecutorService.cs

@@ -42,13 +42,13 @@ namespace PluralKit.Bot
             _logger = logger.ForContext<WebhookExecutorService>();
         }
 
-        public async Task<ulong> ExecuteWebhook(DiscordChannel channel, string name, string avatarUrl, string content, IReadOnlyList<DiscordAttachment> attachments)
+        public async Task<ulong> ExecuteWebhook(DiscordChannel channel, string name, string avatarUrl, string content, IReadOnlyList<DiscordAttachment> attachments, bool allowEveryone)
         {
             _logger.Verbose("Invoking webhook in channel {Channel}", channel.Id);
             
             // Get a webhook, execute it
             var webhook = await _webhookCache.GetWebhook(channel);
-            var id = await ExecuteWebhookInner(channel, webhook, name, avatarUrl, content, attachments);
+            var id = await ExecuteWebhookInner(channel, webhook, name, avatarUrl, content, attachments, allowEveryone);
             
             // Log the relevant metrics
             _metrics.Measure.Meter.Mark(BotMetrics.MessagesProxied);
@@ -59,11 +59,14 @@ namespace PluralKit.Bot
         }
 
         private async Task<ulong> ExecuteWebhookInner(DiscordChannel channel, DiscordWebhook webhook, string name, string avatarUrl, string content,
-            IReadOnlyList<DiscordAttachment> attachments, bool hasRetried = false)
+            IReadOnlyList<DiscordAttachment> attachments, bool allowEveryone, bool hasRetried = false)
         {
+            content = content.Truncate(2000);
+            
             var dwb = new DiscordWebhookBuilder();
             dwb.WithUsername(FixClyde(name).Truncate(80));
-            dwb.WithContent(content.Truncate(2000));
+            dwb.WithContent(content);
+            dwb.AddMentions(content.ParseAllMentions(allowEveryone));
             if (avatarUrl != null) dwb.WithAvatarUrl(avatarUrl);
             
             var attachmentChunks = ChunkAttachmentsOrThrow(attachments, 8 * 1024 * 1024);
@@ -95,7 +98,7 @@ namespace PluralKit.Bot
                         _logger.Warning("Error invoking webhook {Webhook} in channel {Channel}", webhook.Id, webhook.ChannelId);
                         
                         var newWebhook = await _webhookCache.InvalidateAndRefreshWebhook(channel, webhook);
-                        return await ExecuteWebhookInner(channel, newWebhook, name, avatarUrl, content, attachments, hasRetried: true);
+                        return await ExecuteWebhookInner(channel, newWebhook, name, avatarUrl, content, attachments, allowEveryone, hasRetried: true);
                     }
 
                     throw;

PluralKit.Bot/Utils/DiscordUtils.cs

@@ -1,8 +1,10 @@
 using System;
 using System.Collections.Concurrent;
 using System.Collections.Generic;
+using System.Globalization;
 using System.Linq;
 using System.Reflection;
+using System.Text.RegularExpressions;
 using System.Threading.Tasks;
 
 using DSharpPlus;
@@ -124,6 +126,63 @@ namespace PluralKit.Bot
                 .GetProperty("UserCache", BindingFlags.Instance | BindingFlags.NonPublic)
                 ?.GetValue(client);
             return cache != null && cache.TryGetValue(id, out user);
+        }
+        
+                private static readonly Regex USER_MENTION = new Regex("<@!?(\\d{17,19})>");
+        private static readonly Regex ROLE_MENTION = new Regex("<@&(\\d{17,19})>");
+        private static readonly Regex EVERYONE_HERE_MENTION = new Regex("@(everyone|here)");
+        public static DiscordColor? ToDiscordColor(this string color)
+        {
+            if (int.TryParse(color, NumberStyles.HexNumber, null, out var colorInt))
+                return new DiscordColor(colorInt);
+            throw new ArgumentException($"Invalid color string '{color}'.");
+        }
+        
+        public static bool HasMentionPrefix(string content, ref int argPos, out ulong mentionId)
+        {
+            mentionId = 0;
+            
+            // Roughly ported from Discord.Commands.MessageExtensions.HasMentionPrefix
+            if (string.IsNullOrEmpty(content) || content.Length <= 3 || (content[0] != '<' || content[1] != '@'))
+                return false;
+            int num = content.IndexOf('>');
+            if (num == -1 || content.Length < num + 2 || content[num + 1] != ' ' || !TryParseMention(content.Substring(0, num + 1), out mentionId))
+                return false;
+            argPos = num + 2;
+            return true;
+        }
+
+        public static bool TryParseMention(this string potentialMention, out ulong id)
+        {
+            if (ulong.TryParse(potentialMention, out id)) return true;
+
+            var match = USER_MENTION.Match(potentialMention);
+            if (match.Success && match.Index == 0 && match.Length == potentialMention.Length) 
+            {
+                id = ulong.Parse(match.Groups[1].Value, NumberStyles.None, CultureInfo.InvariantCulture);
+                return true;
+            }
+
+            return false;
+        }
+
+        public static IEnumerable<IMention> ParseAllMentions(this string input, bool allowEveryone = false)
+        {
+            var mentions = new List<IMention>();
+            mentions.AddRange(USER_MENTION.Matches(input)
+                .Select(x => new UserMention(ulong.Parse(x.Groups[1].Value)) as IMention));
+            mentions.AddRange(ROLE_MENTION.Matches(input)
+                .Select(x => new RoleMention(ulong.Parse(x.Groups[1].Value)) as IMention));
+            if (EVERYONE_HERE_MENTION.IsMatch(input) && allowEveryone)
+                mentions.Add(new EveryoneMention());
+            return mentions;
+        }
+
+        public static string EscapeMarkdown(this string input)
+        {
+            Regex pattern = new Regex(@"[*_~>`(||)\\]", RegexOptions.Multiline);
+            if (input != null) return pattern.Replace(input, @"\$&");
+            else return input;
         }
     }
 }

PluralKit.Bot/Utils/StringUtils.cs

@@ -1,54 +0,0 @@
-using System;
-using System.Globalization;
-using System.Text.RegularExpressions;
-
-using DSharpPlus.Entities;
-
-namespace PluralKit.Bot
-{
-    public static class StringUtils
-    {
-        private static readonly Regex USER_MENTION = new Regex("^<@!?(\\d{17,19})>$");
-        public static DiscordColor? ToDiscordColor(this string color)
-        {
-            if (int.TryParse(color, NumberStyles.HexNumber, null, out var colorInt))
-                return new DiscordColor(colorInt);
-            throw new ArgumentException($"Invalid color string '{color}'.");
-        }
-        
-        public static bool HasMentionPrefix(string content, ref int argPos, out ulong mentionId)
-        {
-            mentionId = 0;
-            
-            // Roughly ported from Discord.Commands.MessageExtensions.HasMentionPrefix
-            if (string.IsNullOrEmpty(content) || content.Length <= 3 || (content[0] != '<' || content[1] != '@'))
-                return false;
-            int num = content.IndexOf('>');
-            if (num == -1 || content.Length < num + 2 || content[num + 1] != ' ' || !TryParseMention(content.Substring(0, num + 1), out mentionId))
-                return false;
-            argPos = num + 2;
-            return true;
-        }
-
-        public static bool TryParseMention(this string potentialMention, out ulong id)
-        {
-            if (ulong.TryParse(potentialMention, out id)) return true;
-
-            var match = USER_MENTION.Match(potentialMention);
-            if (match.Success) 
-            {
-                id = ulong.Parse(match.Groups[1].Value, NumberStyles.None, CultureInfo.InvariantCulture);
-                return true;
-            }
-
-            return false;
-        }
-
-        public static string EscapeMarkdown(this string input)
-        {
-            Regex pattern = new Regex(@"[*_~>`(||)\\]", RegexOptions.Multiline);
-            if (input != null) return pattern.Replace(input, @"\$&");
-            else return input;
-        }
-    }
-}