prevent report dodging by leaving channel, allow reports to work after leaving the channel too

LightlessSyncServer/LightlessSyncServer/Hubs/LightlessHub.Chat.cs

@@ -334,12 +334,6 @@ public partial class LightlessHub
     {
         var channel = request.Channel.WithNormalizedCustomKey();
 
-        if (!_chatChannelService.TryGetPresence(UserUID, channel, out _))
-        {
-            await Clients.Caller.Client_ReceiveServerMessage(MessageSeverity.Error, "Join the chat channel before reporting messages.").ConfigureAwait(false);
-            return;
-        }
-
         if (!_chatChannelService.TryGetMessage(request.MessageId, out var messageEntry))
         {
             await Clients.Caller.Client_ReceiveServerMessage(MessageSeverity.Error, "Unable to locate the reported message. It may have already expired.").ConfigureAwait(false);

LightlessSyncServer/LightlessSyncServer/Services/ChatChannelService.cs

@@ -1,31 +1,32 @@
-using System;
-using System.Collections.Generic;
-using System.Linq;
-using System.Security.Cryptography;
+using System.Security.Cryptography;
 using LightlessSync.API.Data;
 using LightlessSync.API.Dto.Chat;
 using LightlessSyncServer.Models;
-using Microsoft.Extensions.Logging;
 
 namespace LightlessSyncServer.Services;
 
-public sealed class ChatChannelService
+public sealed class ChatChannelService : IDisposable
 {
     private readonly ILogger<ChatChannelService> _logger;
     private readonly Dictionary<string, ZoneChannelDefinition> _zoneDefinitions;
     private readonly Dictionary<ChannelKey, HashSet<string>> _membersByChannel = new();
     private readonly Dictionary<string, Dictionary<ChannelKey, ChatPresenceEntry>> _presenceByUser = new(StringComparer.Ordinal);
     private readonly Dictionary<ChannelKey, Dictionary<string, ChatParticipantInfo>> _participantsByChannel = new();
+    private readonly Dictionary<ChannelKey, Dictionary<string, InactiveParticipantEntry>> _inactiveParticipantsByChannel = new();
     private readonly Dictionary<ChannelKey, LinkedList<ChatMessageLogEntry>> _messagesByChannel = new();
     private readonly Dictionary<string, (ChannelKey Channel, LinkedListNode<ChatMessageLogEntry> Node)> _messageIndex = new(StringComparer.Ordinal);
     private readonly object _syncRoot = new();
     private const int MaxMessagesPerChannel = 200;
+    private static readonly TimeSpan InactiveParticipantRetention = TimeSpan.FromMinutes(15);
+    private static readonly TimeSpan InactiveParticipantCleanupInterval = TimeSpan.FromMinutes(1);
+    private readonly Timer _inactiveParticipantCleanupTimer;
 
     public ChatChannelService(ILogger<ChatChannelService> logger)
     {
         _logger = logger;
         _zoneDefinitions = ChatZoneDefinitions.Defaults
             .ToDictionary(definition => definition.Key, StringComparer.OrdinalIgnoreCase);
+        _inactiveParticipantCleanupTimer = new Timer(_ => CleanupExpiredInactiveParticipants(), null, InactiveParticipantCleanupInterval, InactiveParticipantCleanupInterval);
     }
 
     public IReadOnlyList<ZoneChatChannelInfoDto> GetZoneChannelInfos() =>
@@ -271,6 +272,22 @@ public sealed class ChatChannelService
             {
                 return true;
             }
+
+            if (_inactiveParticipantsByChannel.TryGetValue(key, out var inactive) &&
+                inactive.TryGetValue(token, out var inactiveEntry))
+            {
+                if (inactiveEntry.ExpiresAt > DateTime.UtcNow)
+                {
+                    participant = inactiveEntry.Participant;
+                    return true;
+                }
+
+                inactive.Remove(token);
+                if (inactive.Count == 0)
+                {
+                    _inactiveParticipantsByChannel.Remove(key);
+                }
+            }
         }
 
         participant = default;
@@ -412,6 +429,7 @@ public sealed class ChatChannelService
             }
 
             participantsByToken[token] = finalParticipant;
+            RemoveInactiveParticipantLocked(key, token);
 
             _logger.LogDebug("Chat presence updated for {User} in {Channel}", userUid, Describe(key));
             return entryToStore;
@@ -446,9 +464,77 @@ public sealed class ChatChannelService
             }
         }
 
+        StoreInactiveParticipantLocked(key, existing.Participant);
         return true;
     }
 
+    private void StoreInactiveParticipantLocked(ChannelKey key, ChatParticipantInfo participant)
+    {
+        if (string.IsNullOrEmpty(participant.Token))
+        {
+            return;
+        }
+
+        if (!_inactiveParticipantsByChannel.TryGetValue(key, out var inactive))
+        {
+            inactive = new Dictionary<string, InactiveParticipantEntry>(StringComparer.Ordinal);
+            _inactiveParticipantsByChannel[key] = inactive;
+        }
+
+        inactive[participant.Token] = new InactiveParticipantEntry(participant, DateTime.UtcNow + InactiveParticipantRetention);
+    }
+
+    private void RemoveInactiveParticipantLocked(ChannelKey key, string token)
+    {
+        if (_inactiveParticipantsByChannel.TryGetValue(key, out var inactive) &&
+            inactive.Remove(token) &&
+            inactive.Count == 0)
+        {
+            _inactiveParticipantsByChannel.Remove(key);
+        }
+    }
+
+    private void CleanupExpiredInactiveParticipants()
+    {
+        lock (_syncRoot)
+        {
+            if (_inactiveParticipantsByChannel.Count == 0)
+            {
+                return;
+            }
+
+            var now = DateTime.UtcNow;
+            var channelsToRemove = new List<ChannelKey>();
+
+            foreach (var (key, inactive) in _inactiveParticipantsByChannel)
+            {
+                var tokensToRemove = new List<string>();
+                foreach (var (token, entry) in inactive)
+                {
+                    if (entry.ExpiresAt <= now)
+                    {
+                        tokensToRemove.Add(token);
+                    }
+                }
+
+                foreach (var token in tokensToRemove)
+                {
+                    inactive.Remove(token);
+                }
+
+                if (inactive.Count == 0)
+                {
+                    channelsToRemove.Add(key);
+                }
+            }
+
+            foreach (var channel in channelsToRemove)
+            {
+                _inactiveParticipantsByChannel.Remove(channel);
+            }
+        }
+    }
+
     private static string GenerateToken()
     {
         Span<byte> buffer = stackalloc byte[8];
@@ -458,4 +544,11 @@ public sealed class ChatChannelService
 
     private static string Describe(ChannelKey key)
         => $"{key.Type}:{key.WorldId}:{key.CustomKey}";
+
+    public void Dispose()
+    {
+        _inactiveParticipantCleanupTimer.Dispose();
+    }
+
+    private readonly record struct InactiveParticipantEntry(ChatParticipantInfo Participant, DateTime ExpiresAt);
 }

LightlessSyncServer/LightlessSyncServices/Discord/DiscordBot.cs

@@ -204,7 +204,7 @@ internal class DiscordBot : IHostedService
             var embed = await BuildChatReportEmbedAsync(dbContext, report, token).ConfigureAwait(false);
 
             var components = new ComponentBuilder()
-                .WithButton("Actioned", $"{ChatReportButtonPrefix}-resolve-{report.ReportId}", ButtonStyle.Danger)
+                .WithButton("Resolve", $"{ChatReportButtonPrefix}-resolve-{report.ReportId}", ButtonStyle.Danger)
                 .WithButton("Dismiss", $"{ChatReportButtonPrefix}-dismiss-{report.ReportId}", ButtonStyle.Secondary)
                 .WithButton("Ban From Chat", $"{ChatReportButtonPrefix}-banchat-{report.ReportId}", ButtonStyle.Danger);
 
@@ -395,7 +395,7 @@ internal class DiscordBot : IHostedService
         switch (action)
         {
             case "resolve":
-                resolutionLabel = "Actioned";
+                resolutionLabel = "Resolved";
                 break;
             case "dismiss":
                 resolutionLabel = "Dismissed";
@@ -431,7 +431,7 @@ internal class DiscordBot : IHostedService
 
         string responseText = action switch
         {
-            "resolve" => "actioned",
+            "resolve" => "resolved",
             "dismiss" => "dismissed",
             "banchat" => "chat access revoked",
             _ => "processed"
@@ -473,7 +473,7 @@ internal class DiscordBot : IHostedService
         embedBuilder.Fields.RemoveAll(f => string.Equals(f.Name, "Resolution", StringComparison.OrdinalIgnoreCase));
         var resolutionText = action switch
         {
-            "resolve" => "Actioned",
+            "resolve" => "Resolved",
             "dismiss" => "Dismissed",
             "banchat" => "Chat access revoked",
             _ => "Processed"