feat(bot): basic webhook username templating

PluralKit.Core/Database/Functions/MessageContext.cs

@@ -25,6 +25,7 @@ public class MessageContext
     public string? SystemTag { get; }
     public string? SystemGuildTag { get; }
     public bool TagEnabled { get; }
+    public string? NameFormat { get; }
     public string? SystemAvatar { get; }
     public string? SystemGuildAvatar { get; }
     public bool AllowAutoproxy { get; }

PluralKit.Core/Database/Functions/ProxyMember.cs

@@ -31,17 +31,23 @@ public class ProxyMember
     public bool AllowAutoproxy { get; }
     public string? Color { get; }
 
+    // If not set, this formatting will be applied to the proxy name
+    public static string DefaultFormat = "{name} {tag}";
+
+    public static string FormatTag(string template, string tag, string name) => StringUtils.SafeFormat(template, new[] {
+            ("{tag}", tag),
+            ("{name}", name)
+        });
+
     public string ProxyName(MessageContext ctx)
     {
+        // TODO: if tag is null it should still format but only if it appears in the formatting.
         var memberName = ServerName ?? DisplayName ?? Name;
-        if (!ctx.TagEnabled)
+        var tag = ctx.SystemGuildTag ?? ctx.SystemTag;
+        if (!ctx.TagEnabled || tag == null)
             return memberName;
 
-        if (ctx.SystemGuildTag != null)
-            return $"{memberName} {ctx.SystemGuildTag}";
-        if (ctx.SystemTag != null)
-            return $"{memberName} {ctx.SystemTag}";
-        return memberName;
+        return FormatTag(ctx.NameFormat ?? DefaultFormat, tag, memberName);
     }
 
     public string? ProxyAvatar(MessageContext ctx) => ServerAvatar ?? WebhookAvatar ?? Avatar ?? ctx.SystemGuildAvatar ?? ctx.SystemAvatar;

PluralKit.Core/Database/Functions/functions.sql

@@ -1,4 +1,4 @@
-create function message_context(account_id bigint, guild_id bigint, channel_id bigint, thread_id bigint)
+create function message_context(account_id bigint, guild_id bigint, channel_id bigint, thread_id bigint)
     returns table (
         allow_autoproxy bool,
 
@@ -10,6 +10,7 @@
         case_sensitive_proxy_tags bool,
         proxy_error_message_enabled bool,
         proxy_switch bool,
+        name_format text,
 
         tag_enabled bool,
         proxy_enabled bool,
@@ -42,6 +43,7 @@ as $$
         system_config.case_sensitive_proxy_tags        as case_sensitive_proxy_tags,
         system_config.proxy_error_message_enabled      as proxy_error_message_enabled,
         system_config.proxy_switch                     as proxy_switch,
+        system_config.name_format                      as name_format,
 
         -- system_guild table
         coalesce(system_guild.tag_enabled, true)       as tag_enabled,
@@ -174,4 +176,4 @@ begin
         if not exists (select 1 from groups where hid = new_hid) then return new_hid; end if;
     end loop;
 end
-$$ language plpgsql volatile;
+$$ language plpgsql volatile;