fix: don't delete rows from messages table when the associated member is deleted

PluralKit.Bot/Commands/Message.cs

@@ -51,7 +51,7 @@ public class ProxiedMessage
 
         var msg = await GetMessageToEdit(ctx);
 
-        if (ctx.System.Id != msg.System.Id)
+        if (ctx.System.Id != msg.System?.Id)
             throw new PKError("Can't edit a message sent by a different system.");
 
         var newContent = ctx.RemainderOrNull().NormalizeLineEndSpacing();
@@ -209,7 +209,7 @@ public class ProxiedMessage
             if (!showContent)
                 throw new PKError(noShowContentError);
 
-            if (message.System.Id != ctx.System.Id)
+            if (message.System?.Id != ctx.System.Id && message.Message.Sender != ctx.Author.Id)
                 throw new PKError("You can only delete your own messages.");
 
             await ctx.Rest.DeleteMessage(message.Message.Channel, message.Message.Mid);

PluralKit.Bot/Handlers/ReactionAdded.cs

@@ -128,7 +128,7 @@ public class ReactionAdded: IEventHandler<MessageReactionAddEvent>
         var system = await _repo.GetSystemByAccount(evt.UserId);
 
         // Can only delete your own message
-        if (msg.System.Id != system?.Id) return;
+        if (msg.System?.Id != system?.Id && msg.Message.Sender != evt.UserId) return;
 
         try
         {
@@ -170,16 +170,17 @@ public class ReactionAdded: IEventHandler<MessageReactionAddEvent>
         try
         {
             var dm = await _cache.GetOrCreateDmChannel(_rest, evt.UserId);
-            await _rest.CreateMessage(dm.Id, new MessageRequest
-            {
-                Embed = await _embeds.CreateMemberEmbed(
-                    msg.System,
-                    msg.Member,
-                    guild,
-                    LookupContext.ByNonOwner,
-                    DateTimeZone.Utc
-                )
-            });
+            if (msg.Member != null)
+                await _rest.CreateMessage(dm.Id, new MessageRequest
+                {
+                    Embed = await _embeds.CreateMemberEmbed(
+                        msg.System,
+                        msg.Member,
+                        guild,
+                        LookupContext.ByNonOwner,
+                        DateTimeZone.Utc
+                    )
+                });
 
             await _rest.CreateMessage(
                 dm.Id,
@@ -202,6 +203,8 @@ public class ReactionAdded: IEventHandler<MessageReactionAddEvent>
         var requiredPerms = PermissionSet.ViewChannel | PermissionSet.SendMessages;
         if (member == null || !(await _cache.PermissionsFor(evt.ChannelId, member)).HasFlag(requiredPerms)) return;
 
+        if (msg.Member == null) return;
+
         var config = await _repo.GetSystemConfig(msg.System.Id);
 
         if (config.PingsEnabled)

PluralKit.Bot/Services/EmbedService.cs

@@ -355,13 +355,20 @@ public class EmbedService
 
         // Put it all together
         var eb = new EmbedBuilder()
-            .Author(new Embed.EmbedAuthor(msg.Member.NameFor(ctx),
-                IconUrl: msg.Member.AvatarFor(ctx).TryGetCleanCdnUrl()))
+            .Author(new Embed.EmbedAuthor(msg.Member?.NameFor(ctx) ?? "(deleted member)",
+                IconUrl: msg.Member?.AvatarFor(ctx).TryGetCleanCdnUrl()))
             .Description(content)
             .Image(showContent ? new Embed.EmbedImage(serverMsg?.Attachments?.FirstOrDefault()?.Url) : null)
             .Field(new Embed.Field("System",
-                msg.System.Name != null ? $"{msg.System.Name} (`{msg.System.Hid}`)" : $"`{msg.System.Hid}`", true))
-            .Field(new Embed.Field("Member", $"{msg.Member.NameFor(ctx)} (`{msg.Member.Hid}`)", true))
+                msg.System == null
+                    ? "*(deleted or unknown system)*"
+                    : msg.System.Name != null ? $"{msg.System.Name} (`{msg.System.Hid}`)" : $"`{msg.System.Hid}`"
+            , true))
+            .Field(new Embed.Field("Member",
+                msg.Member == null
+                    ? "*(deleted member)*"
+                    : $"{msg.Member.NameFor(ctx)} (`{msg.Member.Hid}`)"
+            , true))
             .Field(new Embed.Field("Sent by", userStr, true))
             .Timestamp(DiscordUtils.SnowflakeToInstant(msg.Message.Mid).ToDateTimeOffset().ToString("O"));
 

PluralKit.Bot/Services/LogChannelService.cs

@@ -44,7 +44,7 @@ public class LogChannelService
         var triggerChannel = await _cache.GetChannel(proxiedMessage.Channel);
 
         var system = await _repo.GetSystem(ctx.SystemId.Value);
-        var member = await _repo.GetMember(proxiedMessage.Member);
+        var member = await _repo.GetMember(proxiedMessage.Member!.Value);
 
         // Send embed!
         var embed = _embed.CreateLoggedMessageEmbed(trigger, hookMessage, system.Hid, member, triggerChannel.Name,