using System.Reflection;
using System.Security.Claims;
using System.Text;
using System.Text.Json;
using Microsoft.AspNetCore.Http;
using Microsoft.AspNetCore.Mvc;
using Microsoft.AspNetCore.Routing;
using Microsoft.EntityFrameworkCore;
using RadicadeServer.API.Config;
using RadicadeServer.API.Events;
using RadicadeServer.API.Matchmaking;
using RadicadeServer.API.Notifications;
using RadicadeServer.API.Relationships;
using RadicadeServer.API.Relationships.V2;
using RadicadeServer.Clubs;
using RadicadeServer.DB;
using RadicadeServer.RecNet.Accounts;
using RadicadeServer.RecNet.Auth;
using RadicadeServer.RecNet.Enums;
using RadicadeServer.RecNet.Enums.Messages;
using RadicadeServer.RecNet.Enums.Rooms;
using RadicadeServer.RecNet.Events;
using RadicadeServer.RecNet.Matchmaking;
using RadicadeServer.RecNet.Messages;
using RadicadeServer.RecNet.Relationships;
using RadicadeServer.RecNet.Responses;
using RadicadeServer.RecNet.Rooms;
using RadicadeServer.RoomServer;
using RadicadeServer.Utils;
using Xunit;

namespace RadicadeServer.Tests;

[Collection(DbFactoryCollection.Name)]
public class InviteFlowTests
{
    private const long CreatorId = 42;
    private const long InviteeId = 43;
    private const long StrangerId = 44;
    private const long RoomId = 45;
    private const long EventId = 46;
    private const long ClubId = 47;

    private sealed class TestDbContextFactory : IDbContextFactory<RecDBContext>
    {
        private readonly DbContextOptions<RecDBContext> options = TestDbOptions.Create()
            .UseInMemoryDatabase(Guid.NewGuid().ToString())
            .Options;

        public RecDBContext CreateDbContext() => new(options);
    }

    private sealed record FactorySnapshot(
        IDbContextFactory<RecDBContext> Notify,
        IDbContextFactory<RecDBContext> Room,
        IDbContextFactory<RecDBContext> Matchmaking);

    private static FactorySnapshot SetFactories(IDbContextFactory<RecDBContext> factory)
    {
        var previous = new FactorySnapshot(Notify.DbFactory, RoomUtils.DbFactory, MatchmakingUtils.DbFactory);
        Notify.DbFactory = factory;
        RoomUtils.DbFactory = factory;
        MatchmakingUtils.DbFactory = factory;
        return previous;
    }

    private static void RestoreFactories(FactorySnapshot previous)
    {
        Notify.DbFactory = previous.Notify;
        RoomUtils.DbFactory = previous.Room;
        MatchmakingUtils.DbFactory = previous.Matchmaking;
    }

    private static async Task<(RecDBContext Db, FactorySnapshot Previous)> CreateContextAsync()
    {
        var factory = new TestDbContextFactory();
        var previous = SetFactories(factory);
        var db = factory.CreateDbContext();

        db.Profiles.AddRange(ProfileFor(CreatorId), ProfileFor(InviteeId), ProfileFor(StrangerId));
        db.Players.AddRange(
            new PlayerData { AccountId = CreatorId, Hashword = "test" },
            new PlayerData { AccountId = InviteeId, Hashword = "test" },
            new PlayerData { AccountId = StrangerId, Hashword = "test" });
        await db.SaveChangesAsync();
        return (db, previous);
    }

    private static void SetUser(Controller controller, long userId)
    {
        var identity = new ClaimsIdentity("TestAuth");
        identity.AddClaim(new Claim(ClaimTypes.NameIdentifier, userId.ToString()));
        controller.ControllerContext = new ControllerContext
        {
            HttpContext = new DefaultHttpContext { User = new ClaimsPrincipal(identity) }
        };
    }

    private static void SetFormBody(Controller controller, string body)
    {
        var request = controller.HttpContext.Request;
        request.ContentType = "application/x-www-form-urlencoded";
        request.Body = new MemoryStream(Encoding.UTF8.GetBytes(body));
        request.ContentLength = request.Body.Length;
    }

    private static Profile ProfileFor(long id) => new()
    {
        accountId = id,
        username = $"player{id}",
        displayName = $"Player {id}",
        profileImage = string.Empty,
        createdAt = DateTime.UtcNow
    };

    private static async Task SeedRoomAsync(RecDBContext db, Accessibility accessibility = Accessibility.Public)
    {
        db.Rooms.Add(new RoomData
        {
            RoomId = RoomId,
            Name = "Invite test room",
            CreatorAccountId = CreatorId,
            Accessibility = accessibility,
            MaxPlayers = 8,
            CreatedAt = DateTime.UtcNow
        });
        db.SubRooms.Add(new SubRoom
        {
            RoomId = RoomId,
            SubRoomId = 1,
            Name = "Main",
            MaxPlayers = 8,
            Accessibility = Accessibility.Public,
            UnitySceneId = "invite-test-scene"
        });
        await db.SaveChangesAsync();
    }

    private static async Task<PlayerEventDB> SeedEventAsync(
        RecDBContext db,
        Accessibility eventAccess = Accessibility.Private,
        Accessibility roomAccess = Accessibility.Public)
    {
        await SeedRoomAsync(db, roomAccess);
        var ev = new PlayerEventDB
        {
            PlayerEventId = EventId,
            Name = "Invite test event",
            CreatorPlayerId = CreatorId,
            RoomId = RoomId,
            StartTime = DateTime.UtcNow.AddMinutes(-10),
            EndTime = DateTime.UtcNow.AddHours(1),
            Accessibility = eventAccess
        };
        db.PlayerEvents.Add(ev);
        db.Presences.Add(new RealPresence { playerId = CreatorId, isOnline = true });
        db.Presences.Add(new RealPresence { playerId = InviteeId, isOnline = true });
        await db.SaveChangesAsync();
        return ev;
    }

    [Fact]
    public async Task BulkEventInvitePersistsPendingResponseAndMessageAndAllowsPrivateEventJoin()
    {
        var (db, previousFactories) = await CreateContextAsync();
        await using var disposeDb = db;
        try
        {
            await SeedEventAsync(db, Accessibility.Private, Accessibility.Private);
            var controller = new EventsAPI(db);
            SetUser(controller, CreatorId);
            SetFormBody(controller, $"PlayerEventId={EventId}&InvitedPlayerIds%5B%5D={InviteeId}");

            var result = await controller.BulkInvite();

            Assert.IsType<OkObjectResult>(result);
            var response = await db.PlayerEventResponses.SingleAsync(x => x.PlayerEventId == EventId && x.PlayerId == InviteeId);
            Assert.Equal(EventResponses.Pending, response.Type);
            var message = await db.Messages.SingleAsync(x => x.ToPlayerId == InviteeId);
            Assert.Equal(MessageType.PlayerEventInvitation, message.Type);
            Assert.Equal(EventId, message.PlayerEventId);
            Assert.Equal(CreatorId, message.FromPlayerId);
            Assert.Equal(EventResponses.Pending,
                (await db.PlayerEventResponses.SingleAsync(x => x.PlayerEventId == EventId && x.PlayerId == InviteeId)).Type);

            var invitee = new EventsAPI(db);
            SetUser(invitee, InviteeId);
            Assert.IsType<OkObjectResult>((await invitee.RespondToEventV2(EventId)).Result);

            var match = await MatchmakingUtils.MatchmakeEvent(InviteeId, EventId);
            Assert.Equal(JoinStatus.Success, match.errorCode);
            Assert.Equal(EventId, match.roomInstance?.eventId);
        }
        finally
        {
            RestoreFactories(previousFactories);
        }
    }

    [Fact]
    public async Task PrivateEventRejectsUninvitedRsvpAndDeclinedInviteeCannotReenter()
    {
        var (db, previousFactories) = await CreateContextAsync();
        await using var disposeDb = db;
        try
        {
            await SeedEventAsync(db);

            var strangerRsvp = new EventsAPI(db);
            SetUser(strangerRsvp, StrangerId);
            Assert.IsType<NotFoundResult>((await strangerRsvp.RespondToEventV2(EventId)).Result);

            var invitedRsvp = new EventsAPI(db);
            SetUser(invitedRsvp, InviteeId);
            Assert.IsType<NotFoundResult>((await invitedRsvp.RespondToEventV2(EventId)).Result);

            db.Messages.Add(new Message
            {
                ToPlayerId = InviteeId,
                FromPlayerId = CreatorId,
                Type = MessageType.PlayerEventInvitation,
                PlayerEventId = EventId
            });
            db.PlayerEventResponses.Add(new PlayerEventResponse
            {
                PlayerEventId = EventId,
                PlayerId = InviteeId,
                Type = EventResponses.No
            });
            await db.SaveChangesAsync();

            var match = await MatchmakingUtils.MatchmakeEvent(InviteeId, EventId);
            Assert.Equal(JoinStatus.EventIsPrivate, match.errorCode);

            var resend = new EventsAPI(db);
            SetUser(resend, CreatorId);
            SetFormBody(resend, $"PlayerEventId={EventId}&InvitedPlayerIds%5B%5D={InviteeId}");
            Assert.IsType<OkObjectResult>(await resend.BulkInvite());
            Assert.Equal(2, await db.Messages.CountAsync(x => x.ToPlayerId == InviteeId && x.PlayerEventId == EventId));

            var response = await db.PlayerEventResponses.SingleAsync(x => x.PlayerEventId == EventId && x.PlayerId == InviteeId);
            Assert.Equal(EventResponses.Pending, response.Type);
            var renewedRsvp = new EventsAPI(db);
            SetUser(renewedRsvp, InviteeId);
            Assert.IsType<OkObjectResult>((await renewedRsvp.RespondToEventV2(EventId)).Result);
        }
        finally
        {
            RestoreFactories(previousFactories);
        }
    }

    [Fact]
    public async Task GameInviteCarriesInstanceAndRoomIdsAndGrantsOnlyRecipientPrivateAccess()
    {
        var (db, previousFactories) = await CreateContextAsync();
        await using var disposeDb = db;
        try
        {
            await SeedRoomAsync(db, Accessibility.Private);
            var instance = new RoomInstance
            {
                roomId = RoomId,
                subRoomId = 1,
                isPrivate = true,
                maxCapacity = 8,
                photonRoomId = "private-instance"
            };
            db.RoomInstances.Add(instance);
            await db.SaveChangesAsync();
            db.Presences.Add(new RealPresence
            {
                playerId = CreatorId,
                roomInstance = instance.roomInstanceId,
                isOnline = true
            });
            db.Presences.Add(new RealPresence { playerId = InviteeId, isOnline = true });
            await db.SaveChangesAsync();

            var inviter = new MatchmakingAPI(db);
            SetUser(inviter, CreatorId);
            Assert.True((await inviter.InvitePlayer(InviteeId, instance.roomInstanceId)).success);

            var invite = await db.Messages.SingleAsync(x => x.ToPlayerId == InviteeId);
            Assert.Equal(MessageType.GameInviteV2, invite.Type);
            Assert.Equal(instance.roomInstanceId, RoomInviteDetails.GetInstanceId(invite));
            Assert.Equal(RoomId, invite.RoomId);

            // The client's V2 parser requires this JSON string before its button can join.
            using var data = JsonDocument.Parse(invite.Data);
            Assert.Equal(invite.Id, data.RootElement.GetProperty("InviteId").GetInt64());
            Assert.Equal("Invite test room", data.RootElement.GetProperty("Name").GetString());
            Assert.Equal(0, data.RootElement.GetProperty("InviteMode").GetInt32());
            var inbox = new RadicadeServer.API.Messages.MessagesAPI(db);
            SetUser(inbox, InviteeId);
            await inbox.DeleteMessage(new DeleteMessageRequestDTO { MessageIds = new() { invite.Id } });
            Assert.Empty((await inbox.GetMessages())!);
            Assert.True((await db.Messages.SingleAsync(x => x.Id == invite.Id)).IsDismissed);

            var joiner = new MatchmakingAPI(db);
            SetUser(joiner, InviteeId);
            var accepted = await joiner.AcceptInviteByMessageId(
                data.RootElement.GetProperty("InviteId").GetInt64(), null);
            Assert.Equal(JoinStatus.Success, accepted!.errorCode);
            Assert.Equal(instance.photonRoomId, accepted.roomInstance!.photonRoomId);
            var joined = await joiner.GoToRoomInstance(instance.roomInstanceId, null);
            Assert.Equal(JoinStatus.Success, joined.errorCode);
            Assert.Equal(instance.roomInstanceId,
                (await db.Presences.SingleAsync(x => x.playerId == InviteeId)).roomInstance);

            var forged = new Message
            {
                FromPlayerId = StrangerId,
                ToPlayerId = StrangerId,
                Type = MessageType.GameInvite,
                Data = instance.roomInstanceId.ToString(),
                RoomId = RoomId
            };
            db.Messages.Add(forged);
            await db.SaveChangesAsync();
            var forgedJoiner = new MatchmakingAPI(db);
            SetUser(forgedJoiner, StrangerId);
            var forgedDenied = await forgedJoiner.GoToRoomInstance(instance.roomInstanceId, null);
            Assert.Equal(JoinStatus.RoomInstanceIsPrivate, forgedDenied.errorCode);

            db.Messages.Remove(invite);
            db.Messages.Remove(forged);
            await db.SaveChangesAsync();
            var nextPlayer = new MatchmakingAPI(db);
            SetUser(nextPlayer, StrangerId);
            var denied = await nextPlayer.GoToRoomInstance(instance.roomInstanceId, null);
            Assert.Equal(JoinStatus.RoomInstanceIsPrivate, denied.errorCode);

            var uninvited = new MatchmakingAPI(db);
            SetUser(uninvited, StrangerId);
            var unauthorizedInvite = await uninvited.InvitePlayer(InviteeId, instance.roomInstanceId);
            Assert.False(unauthorizedInvite.success);
        }
        finally
        {
            RestoreFactories(previousFactories);
        }
    }

    /// <summary>
    /// The room half of an invite. Answering a game invite starts with fetching the room it
    /// names (`GET rooms/rooms/{id}?include=5421...` and `rooms/rooms/bulk?id=` for its card),
    /// and a private room used to answer 404 / [] to everyone but its owner - so the one player
    /// who had just been invited could not see the room they were invited to, and the prompt had
    /// nothing to join from. The invite is the access it grants and nothing more: a stranger
    /// still gets 404, and a sender who has left the room stops granting it.
    /// </summary>
    [Fact]
    public async Task InviteAlsoMakesThePrivateRoomFetchableForTheInviteeOnly()
    {
        var (db, previousFactories) = await CreateContextAsync();
        await using var disposeDb = db;
        try
        {
            await SeedRoomAsync(db, Accessibility.Private);

            // A dorm is the shape the live report has: the friend invited from their own dorm,
            // and that is the private room a stranger's fetch answers 404 for.
            var room = await db.Rooms.SingleAsync(x => x.RoomId == RoomId);
            room.IsDorm = true;
            await db.SaveChangesAsync();

            var instance = new RoomInstance
            {
                roomId = RoomId,
                subRoomId = 1,
                isPrivate = true,
                maxCapacity = 8,
                photonRoomId = "private-instance"
            };
            db.RoomInstances.Add(instance);
            await db.SaveChangesAsync();
            db.Presences.Add(new RealPresence
            {
                playerId = CreatorId,
                roomInstance = instance.roomInstanceId,
                isOnline = true
            });
            db.Presences.Add(new RealPresence { playerId = InviteeId, isOnline = true });
            db.Presences.Add(new RealPresence { playerId = StrangerId, isOnline = true });
            await db.SaveChangesAsync();

            var inviter = new MatchmakingAPI(db);
            SetUser(inviter, CreatorId);
            Assert.True((await inviter.InvitePlayer(InviteeId, instance.roomInstanceId)).success);

            // The room itself, through the same handler the client's fetch lands on.
            var inviteeRooms = new RoomServerAPI(db);
            SetUser(inviteeRooms, InviteeId);
            Assert.IsType<OkObjectResult>((await inviteeRooms.GetRoomById(RoomId)).Result);

            var strangerRooms = new RoomServerAPI(db);
            SetUser(strangerRooms, StrangerId);
            Assert.IsType<NotFoundResult>((await strangerRooms.GetRoomById(RoomId)).Result);

            // The card the prompt renders from is the same rule, so the bulk answer carries the
            // room for the invitee and stays empty for everyone else.
            var inviteeBulk = await inviteeRooms.GetBulkRooms(null, new List<long> { RoomId });
            Assert.Single(inviteeBulk!);
            var strangerBulk = await strangerRooms.GetBulkRooms(null, new List<long> { RoomId });
            Assert.Empty(strangerBulk!);

            // The inviter leaving takes the invite's worth with it: there is no instance left to
            // be placed in, so the room goes back to being invisible.
            (await db.Presences.SingleAsync(x => x.playerId == CreatorId)).roomInstance = null;
            await db.SaveChangesAsync();
            Assert.IsType<NotFoundResult>((await inviteeRooms.GetRoomById(RoomId)).Result);
        }
        finally
        {
            RestoreFactories(previousFactories);
        }
    }

    [Theory]
    [InlineData(false)]
    [InlineData(true)]
    public async Task AcceptedInviteKeepsDormLoadableAfterMessageDeletion(bool chatInvite)
    {
        var (db, previousFactories) = await CreateContextAsync();
        await using var disposeDb = db;
        try
        {
            await SeedRoomAsync(db, Accessibility.Private);
            var room = await db.Rooms.SingleAsync();
            room.IsDorm = true;
            var instance = new RoomInstance
            {
                roomId = RoomId, subRoomId = 1, isPrivate = true,
                maxCapacity = 8, photonRoomId = "invite-room-load"
            };
            db.RoomInstances.Add(instance);
            await db.SaveChangesAsync();
            db.Presences.AddRange(
                new RealPresence { playerId = CreatorId, roomInstance = instance.roomInstanceId, isOnline = true },
                new RealPresence { playerId = InviteeId, isOnline = true });
            await db.SaveChangesAsync();
            var inviter = new MatchmakingAPI(db);
            SetUser(inviter, CreatorId);
            Assert.True((await inviter.InvitePlayer(InviteeId, instance.roomInstanceId)).success);
            var invite = await db.Messages.SingleAsync();
            var accept = new MatchmakingAPI(db);
            SetUser(accept, InviteeId);
            if (chatInvite)
            {
                db.Chats.Add(new ChatThread
                {
                    chatThreadId = 70, chatThreadName = "",
                    playerIds = $"[{InviteeId},{CreatorId}]",
                    messages = JsonSerializer.Serialize(new[] { new ChatMessage
                    {
                        chatMessageId = 2, chatThreadeId = 70, senderPlayerId = CreatorId,
                        timeSent = DateTime.UtcNow,
                        contents = "{\"Type\":1,\"Version\":1,\"Data\":\"Party invite\"}"
                    } })
                });
                await db.SaveChangesAsync();
                Assert.Equal(JoinStatus.Success, (await accept.MatchmakeChatInvite(70, 2, null))!.errorCode);
            }
            else
                Assert.Equal(JoinStatus.Success, (await accept.AcceptInviteByMessageId(invite.Id, null))!.errorCode);

            // Inbox cleanup and the host leaving must not undo an accepted room admission.
            db.Messages.Remove(invite);
            (await db.Presences.SingleAsync(x => x.playerId == CreatorId)).roomInstance = null;
            await db.SaveChangesAsync();
            var rooms = new RoomServerAPI(db);
            SetUser(rooms, InviteeId);
            var loaded = Assert.IsType<OkObjectResult>((await rooms.GetRoomById(RoomId)).Result);
            Assert.NotEmpty(Assert.IsType<FullRoom>(loaded.Value).SubRooms);
            Assert.Single((await rooms.GetBulkRooms(null, new List<long> { RoomId }))!);
            SetUser(rooms, StrangerId);
            Assert.IsType<NotFoundResult>((await rooms.GetRoomById(RoomId)).Result);

            var presence = await db.Presences.SingleAsync(x => x.playerId == InviteeId);
            presence.isOnline = false;
            await db.SaveChangesAsync();
            SetUser(rooms, InviteeId);
            Assert.IsType<NotFoundResult>((await rooms.GetRoomById(RoomId)).Result);
            presence.isOnline = true;
            presence.roomInstance = null;
            await db.SaveChangesAsync();
            Assert.IsType<NotFoundResult>((await rooms.GetRoomById(RoomId)).Result);
        }
        finally { RestoreFactories(previousFactories); }
    }

    [Fact]
    public async Task ExistingMemberCanForwardPrivateRoomInviteAndTheInviteeCanJoin()
    {
        var (db, previousFactories) = await CreateContextAsync();
        await using var disposeDb = db;
        try
        {
            await SeedRoomAsync(db, Accessibility.Private);
            var instance = new RoomInstance
            {
                roomId = RoomId,
                subRoomId = 1,
                isPrivate = true,
                maxCapacity = 8,
                photonRoomId = "forwarded-private-instance"
            };
            db.RoomInstances.Add(instance);
            db.Presences.AddRange(
                new RealPresence { playerId = CreatorId, roomInstance = instance.roomInstanceId, isOnline = true },
                new RealPresence { playerId = InviteeId, roomInstance = instance.roomInstanceId, isOnline = true },
                new RealPresence { playerId = StrangerId, isOnline = true });
            await db.SaveChangesAsync();
            db.Messages.Add(new Message
            {
                ToPlayerId = InviteeId,
                FromPlayerId = CreatorId,
                Type = MessageType.GameInvite,
                Data = instance.roomInstanceId.ToString(),
                RoomId = RoomId
            });
            await db.SaveChangesAsync();

            var inviter = new MatchmakingAPI(db);
            SetUser(inviter, InviteeId);
            Assert.True((await inviter.InvitePlayer(StrangerId, instance.roomInstanceId)).success);
            var forwardedInvite = await db.Messages.SingleAsync(x => x.ToPlayerId == StrangerId);
            Assert.Equal(InviteeId, forwardedInvite.FromPlayerId);

            var joiner = new MatchmakingAPI(db);
            SetUser(joiner, StrangerId);
            var joined = await joiner.GoToRoomInstance(instance.roomInstanceId, null);
            Assert.Equal(JoinStatus.Success, joined.errorCode);
        }
        finally
        {
            RestoreFactories(previousFactories);
        }
    }

    [Fact]
    public async Task PlayerInPrivateInstanceOfPublicRoomCanInvitePartyMemberToJoin()
    {
        var (db, previousFactories) = await CreateContextAsync();
        await using var disposeDb = db;
        try
        {
            await SeedRoomAsync(db, Accessibility.Public);
            var instance = new RoomInstance
            {
                roomId = RoomId,
                subRoomId = 1,
                isPrivate = true,
                maxCapacity = 8,
                photonRoomId = "player-private-instance"
            };
            db.RoomInstances.Add(instance);
            db.Presences.Add(new RealPresence
            {
                playerId = StrangerId,
                roomInstance = instance.roomInstanceId,
                isOnline = true
            });
            db.Presences.Add(new RealPresence { playerId = InviteeId, isOnline = true });
            await db.SaveChangesAsync();

            var inviter = new MatchmakingAPI(db);
            SetUser(inviter, StrangerId);
            Assert.True((await inviter.InvitePlayer(InviteeId, instance.roomInstanceId)).success);

            var invite = await db.Messages.SingleAsync(x => x.ToPlayerId == InviteeId);
            Assert.Equal(StrangerId, invite.FromPlayerId);
            Assert.Equal(instance.roomInstanceId, RoomInviteDetails.GetInstanceId(invite));
            Assert.Equal(RoomId, invite.RoomId);

            var joiner = new MatchmakingAPI(db);
            SetUser(joiner, InviteeId);
            var joined = await joiner.GoToRoomInstance(instance.roomInstanceId, null);
            Assert.Equal(JoinStatus.Success, joined.errorCode);
        }
        finally
        {
            RestoreFactories(previousFactories);
        }
    }

    [Fact]
    public async Task CoOwnerRoleInviteCanBeAcceptedByInviteeButNotForgedByAnotherPlayer()
    {
        var (db, previousFactories) = await CreateContextAsync();
        await using var disposeDb = db;
        try
        {
            await SeedRoomAsync(db);
            var api = new RoomServerAPI(db);
            SetUser(api, CreatorId);
            SetFormBody(api, "role=30");
            var inviteResult = await api.InvitePlayerToRole(RoomId, InviteeId);
            Assert.True(inviteResult!.success);

            var inviteMessage = await db.Messages.SingleAsync(x => x.ToPlayerId == InviteeId);
            Assert.Equal(MessageType.RoomCoOwnerInvited, inviteMessage.Type);
            Assert.Equal(RoomId, inviteMessage.RoomId);
            Assert.Equal(RoleType.None,
                (await db.RoomRoles.SingleAsync(x => x.RoomId == RoomId && x.AccountId == InviteeId)).Role);

            var forged = new RoomServerAPI(db);
            SetUser(forged, StrangerId);
            SetFormBody(forged, "role=30");
            Assert.False((await forged.SetPlayerRole(RoomId, InviteeId))!.success);

            var acceptance = new RoomServerAPI(db);
            SetUser(acceptance, InviteeId);
            SetFormBody(acceptance, "");
            Assert.True((await acceptance.SetPlayerRole(RoomId, InviteeId))!.success);
            Assert.Equal(RoleType.CoOwner,
                (await db.RoomRoles.SingleAsync(x => x.RoomId == RoomId && x.AccountId == InviteeId)).Role);
            Assert.Contains(await db.Messages.ToListAsync(), x => x.ToPlayerId == InviteeId && x.Type == MessageType.RoomCoOwnerAdded);
        }
        finally
        {
            RestoreFactories(previousFactories);
        }
    }

    [Fact]
    public async Task ClubInviteAddsConfiguredMembershipAndRequiresCoownerAuthority()
    {
        var (db, previousFactories) = await CreateContextAsync();
        await using var disposeDb = db;
        try
        {
            await ClubStore.SaveAsync(db, new List<ClubRecord>
            {
                new() { clubId = ClubId, ownerPlayerId = CreatorId, name = "Test club" }
            });

            var unauthorized = new ClubsAPI(db);
            SetUser(unauthorized, InviteeId);
            SetFormBody(unauthorized, $"accountId={StrangerId}&membershipType=10");
            var denied = await unauthorized.InviteMember(ClubId);
            Assert.IsType<ObjectResult>(denied);
            Assert.Equal(StatusCodes.Status403Forbidden, ((ObjectResult)denied).StatusCode);

            var api = new ClubsAPI(db);
            SetUser(api, CreatorId);
            SetFormBody(api, $"accountId={InviteeId}&membershipType=20");
            var result = await api.InviteMember(ClubId);
            Assert.IsType<OkObjectResult>(result);

            var updated = await ClubStore.GetAsync(db, ClubId);
            Assert.Equal(ClubMembershipTypes.PendingInvited, ClubStore.GetMembershipType(updated, InviteeId));
            Assert.Equal(1, ClubStore.GetMemberCount(updated));
            var pendingMember = Assert.Single(ClubStore.GetMembers(updated), member => member.AccountId == InviteeId);
            Assert.Equal(CreatorId, pendingMember.InviterAccountId);
            Assert.Equal(ClubMembershipTypes.PendingInvited, pendingMember.MembershipType);
            var pendingWireMember = Assert.IsType<Dictionary<string, object?>>(
                ClubStore.BuildMember(pendingMember, updated, ProfileFor(InviteeId)));
            Assert.Equal(0, pendingWireMember["membershipStatus"]);
            Assert.Equal(CreatorId, pendingWireMember["inviterAccountId"]);

            var message = await db.Messages.SingleAsync(x => x.ToPlayerId == InviteeId);
            Assert.Equal(MessageType.ClubModeratorInvited, message.Type);
            Assert.Equal(ClubId.ToString(), message.Data);
            Assert.Equal(ClubMembershipTypes.Moderator.ToString(), message.Details);

            // Only the invitee can activate the stored tier; before acceptance the
            // pending row isn't counted as a member or given the invited role.
            var forgedAcceptance = new ClubsAPI(db);
            SetUser(forgedAcceptance, StrangerId);
            Assert.IsType<BadRequestObjectResult>(await forgedAcceptance.AcceptClubInvitation(ClubId));

            var acceptance = new ClubsAPI(db);
            SetUser(acceptance, InviteeId);
            var accepted = Assert.IsType<OkObjectResult>(await acceptance.AcceptClubInvitation(ClubId));
            var acceptedClub = await ClubStore.GetAsync(db, ClubId);
            Assert.Equal(ClubMembershipTypes.Moderator, ClubStore.GetMembershipType(acceptedClub, InviteeId));
            Assert.Equal(2, ClubStore.GetMemberCount(acceptedClub));
            var activeMember = Assert.Single(ClubStore.GetMembers(acceptedClub), member => member.AccountId == InviteeId);
            var activeWireMember = Assert.IsType<Dictionary<string, object?>>(
                ClubStore.BuildMember(activeMember, acceptedClub, ProfileFor(InviteeId)));
            Assert.Equal(1, activeWireMember["membershipStatus"]);
            Assert.Contains("Moderator", JsonSerializer.Serialize(accepted.Value));
        }
        finally
        {
            RestoreFactories(previousFactories);
        }
    }

    // ---- The spellings a 20230831 client can post ---------------------------------

    /// <summary>
    /// The invite surface is pinned by shape because a 404 is what the player reads as
    /// `Invite Failed!`: the bare form spelling the September client provably posts (its own
    /// log shows `POST /matchmaking/invite` with a form body on an Invite press), the path
    /// spelling beside it for a build that puts the target in the path, and the offline variant
    /// beside the api routes.
    ///
    /// The client's `matchmake/invite/{0}` is NOT a send spelling. It sits in the contiguous
    /// `matchmake/*` JOIN family, so it serves the accept-by-invite-id spelling
    /// (<see cref="MatchmakingAPI.AcceptInviteByMessageId"/>), beside the chat-party
    /// acceptance `matchmake/chatinvite/{threadId}/{messageId}`. Treating the path as a send
    /// would invite whatever account happened to hold the same number as an invite's own
    /// message id.
    /// </summary>
    [Fact]
    public void InviteIsServedUnderEverySpellingTheClientsPost()
    {
        var sends = typeof(MatchmakingAPI).GetMethod(nameof(MatchmakingAPI.Invite))!
            .GetCustomAttributes<HttpPostAttribute>()
            .Select(attribute => attribute.Template!)
            .ToArray();

        Assert.Contains("invite", sends);
        Assert.Contains("invite/{playerId:long}", sends);
        Assert.DoesNotContain(sends, route => route.StartsWith("matchmake/", StringComparison.Ordinal));

        Assert.Equal("matchmake/invite/{inviteId:long}",
            Assert.Single(typeof(MatchmakingAPI)
                .GetMethod(nameof(MatchmakingAPI.AcceptInviteByMessageId))!
                .GetCustomAttributes<HttpPostAttribute>()).Template);
        Assert.Equal("matchmake/chatinvite/{threadId:long}/{messageId:long}",
            Assert.Single(typeof(MatchmakingAPI)
                .GetMethod(nameof(MatchmakingAPI.MatchmakeChatInvite))!
                .GetCustomAttributes<HttpPostAttribute>()).Template);

        var offline = typeof(MatchmakingAPI).GetMethod(nameof(MatchmakingAPI.SendOfflineInvite))!;
        Assert.Equal("~/api/offlineinvite/v1/send",
            Assert.Single(offline.GetCustomAttributes<HttpPostAttribute>()).Template);

        // The party-invite link lifetime rides the settings routes, as a bare single-key object:
        // the api host the sender's client reads, and the chat host the receiver's card fetches
        // when a party invite message arrives.
        var partyInviteRoutes = typeof(PlayerSettingsAPI)
            .GetMethod(nameof(PlayerSettingsAPI.GetPartyInviteSettings))!
            .GetCustomAttributes<HttpGetAttribute>()
            .Select(attribute => attribute.Template!)
            .ToArray();
        Assert.Contains("partyinvite", partyInviteRoutes);
        Assert.Contains("~/chat/settings/partyinvite", partyInviteRoutes);
        Assert.Contains("api/settings", typeof(PlayerSettingsAPI)
            .GetCustomAttributes<RouteAttribute>().Select(attribute => attribute.Template));
    }

    [Fact]
    public void PartyInviteSettingsAnswerTheBareSingleKeyObject()
    {
        using var db = new RecDBContext(TestDbOptions.Create()
            .UseInMemoryDatabase(Guid.NewGuid().ToString()).Options);

        var result = Assert.IsType<OkObjectResult>(new PlayerSettingsAPI(db).GetPartyInviteSettings());

        using var json = JsonDocument.Parse(JsonSerializer.Serialize(result.Value));
        var property = Assert.Single(json.RootElement.EnumerateObject());
        Assert.Equal("InviteLinkLifetimeInMinutes", property.Name);
        Assert.Equal(
            JsonValueKind.Number,
            property.Value.ValueKind);
    }

    /// <summary>
    /// The path spelling carries no instance at all, so the invite has to mean "the instance I am
    /// standing in" - the caller's own presence row, which is the same row the invite insists the
    /// inviter be live in.
    /// </summary>
    [Fact]
    public async Task PathShapedInviteWithoutAnInstanceInvitesIntoTheCallersCurrentInstance()
    {
        var (db, previousFactories) = await CreateContextAsync();
        await using var disposeDb = db;
        try
        {
            await SeedRoomAsync(db, Accessibility.Private);
            var instance = new RoomInstance
            {
                roomId = RoomId,
                subRoomId = 1,
                isPrivate = true,
                maxCapacity = 8,
                photonRoomId = "path-shaped-invite"
            };
            db.RoomInstances.Add(instance);
            db.Presences.AddRange(
                new RealPresence { playerId = CreatorId, roomInstance = instance.roomInstanceId, isOnline = true },
                new RealPresence { playerId = InviteeId, isOnline = true });
            await db.SaveChangesAsync();

            var api = new MatchmakingAPI(db);
            SetUser(api, CreatorId);
            api.Request.RouteValues = new RouteValueDictionary { ["playerId"] = InviteeId.ToString() };

            var result = await api.Invite();

            Assert.True(result!.success);
            var invite = await db.Messages.SingleAsync(x => x.ToPlayerId == InviteeId);
            Assert.Equal(MessageType.GameInviteV2, invite.Type);
            Assert.Equal(CreatorId, invite.FromPlayerId);
            Assert.Equal(instance.roomInstanceId, RoomInviteDetails.GetInstanceId(invite));
            Assert.Equal(RoomId, invite.RoomId);
        }
        finally
        {
            RestoreFactories(previousFactories);
        }
    }

    /// <summary>
    /// No instance in the request AND none on the caller is the one case worth refusing loudly:
    /// the invite would otherwise be stored pointing at nothing, and the recipient's client would
    /// read a join prompt for a room that does not exist.
    /// </summary>
    [Fact]
    public async Task InviteWithNoInstanceAndNoPresenceIsRefusedWithoutStoringAnything()
    {
        var (db, previousFactories) = await CreateContextAsync();
        await using var disposeDb = db;
        try
        {
            var api = new MatchmakingAPI(db);
            SetUser(api, CreatorId);
            api.Request.RouteValues = new RouteValueDictionary { ["playerId"] = InviteeId.ToString() };

            var result = await api.Invite();

            Assert.False(result!.success);
            Assert.Empty(await db.Messages.ToListAsync());
        }
        finally
        {
            RestoreFactories(previousFactories);
        }
    }

    /// <summary>
    /// An offline invite is the same stored game invite: the target simply has no hub frame to
    /// receive, and reads the stored message when they next sign in. Nothing about the invite is
    /// weakened for them - the instance and the room still name where to go.
    /// </summary>
    [Fact]
    public async Task OfflineInviteStoresTheSameGameInviteForATargetWithNoPresence()
    {
        var (db, previousFactories) = await CreateContextAsync();
        await using var disposeDb = db;
        try
        {
            await SeedRoomAsync(db);
            var instance = new RoomInstance
            {
                roomId = RoomId,
                subRoomId = 1,
                isPrivate = false,
                maxCapacity = 8,
                photonRoomId = "offline-invite"
            };
            db.RoomInstances.Add(instance);
            db.Presences.Add(new RealPresence
            {
                playerId = CreatorId,
                roomInstance = instance.roomInstanceId,
                isOnline = true
            });
            await db.SaveChangesAsync();

            var api = new MatchmakingAPI(db);
            SetUser(api, CreatorId);
            SetFormBody(api, $"invitedPlayerId={InviteeId}&roomInstanceId={instance.roomInstanceId}");

            var result = await api.SendOfflineInvite();

            Assert.True(result.success);
            var invite = await db.Messages.SingleAsync(x => x.ToPlayerId == InviteeId);
            Assert.Equal(MessageType.GameInviteV2, invite.Type);
            Assert.Equal(CreatorId, invite.FromPlayerId);
            Assert.Equal(instance.roomInstanceId, RoomInviteDetails.GetInstanceId(invite));
            Assert.Equal(RoomId, invite.RoomId);
        }
        finally
        {
            RestoreFactories(previousFactories);
        }
    }

    // ---- Accepting ---------------------------------------------------------------

    /// <summary>
    /// The client's accept spelling for a game invite is its own `matchmake/invite/{0}`, the id
    /// being the invite message the hub pushed. The invite authorizes that exact instance for
    /// its recipient - a private instance is what an invite exists to get into - and the move
    /// is the same presence write a join performs, so the client's follow-up sees the recipient
    /// standing in the sender's instance.
    /// </summary>
    [Fact]
    public async Task AcceptingAStoredGameInviteMovesTheInviteeIntoTheInviterInstance()
    {
        var (db, previousFactories) = await CreateContextAsync();
        await using var disposeDb = db;
        try
        {
            await SeedRoomAsync(db, Accessibility.Private);
            var instance = new RoomInstance
            {
                roomId = RoomId,
                subRoomId = 1,
                isPrivate = true,
                maxCapacity = 8,
                photonRoomId = "accepted-game-invite"
            };
            db.RoomInstances.Add(instance);
            db.Presences.AddRange(
                new RealPresence { playerId = CreatorId, roomInstance = instance.roomInstanceId, isOnline = true },
                new RealPresence { playerId = InviteeId, isOnline = true });
            await db.SaveChangesAsync();

            db.Messages.Add(new Message
            {
                FromPlayerId = CreatorId,
                ToPlayerId = InviteeId,
                Type = MessageType.GameInvite,
                Data = instance.roomInstanceId.ToString(),
                RoomId = RoomId
            });
            await db.SaveChangesAsync();
            var invite = await db.Messages.SingleAsync(x => x.ToPlayerId == InviteeId);

            var accept = new MatchmakingAPI(db);
            SetUser(accept, InviteeId);
            var result = await accept.AcceptInviteByMessageId(invite.Id, null);

            Assert.NotNull(result);
            Assert.Equal(JoinStatus.Success, result!.errorCode);
            Assert.Equal(instance.roomInstanceId, result.roomInstance?.roomInstanceId);
            var presence = await db.Presences.SingleAsync(x => x.playerId == InviteeId);
            Assert.Equal(instance.roomInstanceId, presence.roomInstance);
            Assert.True(presence.isOnline);
            Assert.Equal(JoinStatus.Success, presence.errorCode);
        }
        finally
        {
            RestoreFactories(previousFactories);
        }
    }

    /// <summary>
    /// Every way a game invite can be stale or forged is answered with the code the client
    /// already has for it, rather than with a status it reads as a network failure: someone
    /// else's invite is expired, a note the caller wrote themselves is not an invite, a sender
    /// with no live session is not online, a sender who moved on makes the invite stale, and an
    /// instance that is gone names nothing to join.
    /// </summary>
    [Fact]
    public async Task AcceptingAGameInviteRefusesStaleForgedAndOfflineInvitesByName()
    {
        var (db, previousFactories) = await CreateContextAsync();
        await using var disposeDb = db;
        try
        {
            await SeedRoomAsync(db, Accessibility.Private);
            var instance = new RoomInstance
            {
                roomId = RoomId,
                subRoomId = 1,
                isPrivate = true,
                maxCapacity = 8,
                photonRoomId = "refused-game-invite"
            };
            db.RoomInstances.Add(instance);
            db.Presences.AddRange(
                new RealPresence { playerId = CreatorId, roomInstance = instance.roomInstanceId, isOnline = true },
                new RealPresence { playerId = InviteeId, isOnline = true });
            await db.SaveChangesAsync();

            Message Store(long to, long from, string data)
            {
                var message = new Message
                {
                    FromPlayerId = from,
                    ToPlayerId = to,
                    Type = MessageType.GameInvite,
                    Data = data,
                    RoomId = RoomId
                };
                db.Messages.Add(message);
                db.SaveChanges();
                return message;
            }

            async Task<MatchResponse?> AcceptAs(long caller, long inviteId)
            {
                var api = new MatchmakingAPI(db);
                SetUser(api, caller);
                return await api.AcceptInviteByMessageId(inviteId, null);
            }

            // Addressed to someone else: the caller has no such invite.
            var foreign = Store(StrangerId, CreatorId, instance.roomInstanceId.ToString());
            var foreignResult = await AcceptAs(InviteeId, foreign.Id);
            Assert.Equal(JoinStatus.RoomInviteExpired, foreignResult!.errorCode);
            Assert.Null(foreignResult.roomInstance);

            // Written by the caller themselves.
            var selfSent = Store(InviteeId, InviteeId, instance.roomInstanceId.ToString());
            Assert.Equal(JoinStatus.ChatMessageNotAnInvite, (await AcceptAs(InviteeId, selfSent.Id))!.errorCode);

            // The sender has no live session to be standing in the instance.
            var fromOffline = Store(InviteeId, StrangerId, instance.roomInstanceId.ToString());
            Assert.Equal(JoinStatus.PlayerNotOnline, (await AcceptAs(InviteeId, fromOffline.Id))!.errorCode);

            // The sender moved to another instance, so the invite no longer names where they are.
            var elsewhere = new RoomInstance
            {
                roomId = RoomId,
                subRoomId = 1,
                isPrivate = true,
                maxCapacity = 8,
                photonRoomId = "somewhere-else"
            };
            db.RoomInstances.Add(elsewhere);
            await db.SaveChangesAsync();
            (await db.Presences.SingleAsync(x => x.playerId == CreatorId)).roomInstance = elsewhere.roomInstanceId;
            await db.SaveChangesAsync();
            var moved = Store(InviteeId, CreatorId, instance.roomInstanceId.ToString());
            Assert.Equal(JoinStatus.RoomInviteExpired, (await AcceptAs(InviteeId, moved.Id))!.errorCode);

            // The named instance is no longer live.
            (await db.Presences.SingleAsync(x => x.playerId == CreatorId)).roomInstance = 999_999;
            await db.SaveChangesAsync();
            var gone = Store(InviteeId, CreatorId, "999999");
            Assert.Equal(JoinStatus.RoomIsNotActive, (await AcceptAs(InviteeId, gone.Id))!.errorCode);
        }
        finally
        {
            RestoreFactories(previousFactories);
        }
    }

    /// <summary>
    /// The chat-party acceptance the client spells `matchmake/chatinvite/{threadId}/{messageId}`:
    /// when the message is stored, its sender is the inviter and their live instance is the
    /// destination - the same stored thread the chat surface serves, read here for who wrote
    /// the invite rather than for what it says.
    /// </summary>
    [Fact]
    public async Task AcceptingAChatInviteResolvesTheInviterFromTheStoredMessage()
    {
        var (db, previousFactories) = await CreateContextAsync();
        await using var disposeDb = db;
        try
        {
            await SeedRoomAsync(db, Accessibility.Private);
            var instance = new RoomInstance
            {
                roomId = RoomId,
                subRoomId = 1,
                isPrivate = true,
                maxCapacity = 8,
                photonRoomId = "accepted-chat-invite"
            };
            db.RoomInstances.Add(instance);
            db.Presences.AddRange(
                new RealPresence { playerId = CreatorId, roomInstance = instance.roomInstanceId, isOnline = true },
                new RealPresence { playerId = InviteeId, isOnline = true });
            await db.SaveChangesAsync();

            const long ThreadId = 70;
            db.Chats.Add(new ChatThread
            {
                chatThreadId = ThreadId,
                chatThreadName = "",
                playerIds = $"[{InviteeId},{CreatorId}]",
                messages = JsonSerializer.Serialize(new List<ChatMessage>
                {
                    new()
                    {
                        chatMessageId = 2,
                        chatThreadeId = ThreadId,
                        senderPlayerId = CreatorId,
                        timeSent = DateTime.UtcNow,
                        contents = "\"come hang out\""
                    }
                })
            });
            await db.SaveChangesAsync();

            var accept = new MatchmakingAPI(db);
            SetUser(accept, InviteeId);
            var result = await accept.MatchmakeChatInvite(ThreadId, 2, null);

            Assert.NotNull(result);
            Assert.Equal(JoinStatus.Success, result!.errorCode);
            Assert.Equal(instance.roomInstanceId, result.roomInstance?.roomInstanceId);
            Assert.Equal(instance.roomInstanceId,
                (await db.Presences.SingleAsync(x => x.playerId == InviteeId)).roomInstance);
        }
        finally
        {
            RestoreFactories(previousFactories);
        }
    }

    /// <summary>
    /// A message id this server never stored falls back to the thread's single other member -
    /// the only person a party invite in that conversation could be from. A caller who is not
    /// in the thread is refused by name, and a stored message that is too old (or written by
    /// the caller) is refused with the code the client already has for it.
    /// </summary>
    [Fact]
    public async Task ChatInviteAcceptFallsBackToTheThreadsOtherMemberAndRefusesTheRest()
    {
        var (db, previousFactories) = await CreateContextAsync();
        await using var disposeDb = db;
        try
        {
            await SeedRoomAsync(db, Accessibility.Private);
            var instance = new RoomInstance
            {
                roomId = RoomId,
                subRoomId = 1,
                isPrivate = true,
                maxCapacity = 8,
                photonRoomId = "chat-invite-fallback"
            };
            db.RoomInstances.Add(instance);
            db.Presences.AddRange(
                new RealPresence { playerId = CreatorId, roomInstance = instance.roomInstanceId, isOnline = true },
                new RealPresence { playerId = InviteeId, isOnline = true });
            await db.SaveChangesAsync();

            const long ThreadId = 71;
            const long ExpiredThreadId = 72;
            const long ForeignThreadId = 73;
            db.Chats.AddRange(
                new ChatThread
                {
                    chatThreadId = ThreadId,
                    chatThreadName = "",
                    playerIds = $"[{InviteeId},{CreatorId}]",
                    messages = "[]"
                },
                new ChatThread
                {
                    chatThreadId = ExpiredThreadId,
                    chatThreadName = "",
                    playerIds = $"[{InviteeId},{CreatorId}]",
                    messages = JsonSerializer.Serialize(new List<ChatMessage>
                    {
                        new()
                        {
                            chatMessageId = 5,
                            chatThreadeId = ExpiredThreadId,
                            senderPlayerId = CreatorId,
                            timeSent = DateTime.UtcNow.AddMinutes(-(PlayerSettingsAPI.InviteLinkLifetimeInMinutes + 5)),
                            contents = "\"too old\""
                        }
                    })
                },
                new ChatThread
                {
                    chatThreadId = ForeignThreadId,
                    chatThreadName = "",
                    playerIds = $"[{CreatorId},{StrangerId}]",
                    messages = "[]"
                });
            await db.SaveChangesAsync();

            // Not stored, exactly one other member: they are the inviter.
            var fallback = new MatchmakingAPI(db);
            SetUser(fallback, InviteeId);
            var fallbackResult = await fallback.MatchmakeChatInvite(ThreadId, 77, null);
            Assert.Equal(JoinStatus.Success, fallbackResult!.errorCode);
            Assert.Equal(instance.roomInstanceId,
                (await db.Presences.SingleAsync(x => x.playerId == InviteeId)).roomInstance);

            var expired = new MatchmakingAPI(db);
            SetUser(expired, InviteeId);
            Assert.Equal(JoinStatus.RoomInviteExpired,
                (await expired.MatchmakeChatInvite(ExpiredThreadId, 5, null))!.errorCode);

            var foreign = new MatchmakingAPI(db);
            SetUser(foreign, InviteeId);
            Assert.Equal(JoinStatus.ChatPartyInviteNotFound,
                (await foreign.MatchmakeChatInvite(ForeignThreadId, 1, null))!.errorCode);
        }
        finally
        {
            RestoreFactories(previousFactories);
        }
    }

    [Fact]
    public async Task FriendInviteCreatesReciprocalPendingRowsAndDurableMessage()
    {
        var (db, previousFactories) = await CreateContextAsync();
        await using var disposeDb = db;
        try
        {
            var sender = new RelationshipsV2(db);
            SetUser(sender, CreatorId);

            Assert.IsType<OkObjectResult>(await sender.SendFriendRequest(InviteeId));

            Assert.Equal(RelationshipType.FriendRequestSent,
                (await db.Relationships.SingleAsync(x => x.AccountId == CreatorId && x.PlayerId == InviteeId)).RelationshipType);
            Assert.Equal(RelationshipType.FriendRequestReceived,
                (await db.Relationships.SingleAsync(x => x.AccountId == InviteeId && x.PlayerId == CreatorId)).RelationshipType);
            var invite = await db.Messages.SingleAsync(x => x.ToPlayerId == InviteeId);
            Assert.Equal(MessageType.FriendInvite, invite.Type);
            Assert.Equal(CreatorId, invite.FromPlayerId);
        }
        finally
        {
            RestoreFactories(previousFactories);
        }
    }

    [Fact]
    public async Task TheBroadcasterKeepsTheirOwnInstanceAndAViewerIsMatchedElsewhere()
    {
        // The instance a broadcaster registers is their own room. A viewer who may join the
        // event is still not placed in it - a broadcast advertises the session, it does not
        // open it - so matchmaking hands them the event's ordinary instance instead.
        var (db, previousFactories) = await CreateContextAsync();
        await using var disposeDb = db;
        try
        {
            var ev = await SeedEventAsync(db, Accessibility.Public, Accessibility.Public);
            ev.IsMultiInstance = true;

            var ordinary = new RoomInstance { roomInstanceId = 500, roomId = RoomId, subRoomId = 1, eventId = EventId, maxCapacity = 8 };
            var broadcast = new RoomInstance { roomInstanceId = 501, roomId = RoomId, subRoomId = 1, eventId = EventId, maxCapacity = 8 };
            db.RoomInstances.AddRange(ordinary, broadcast);
            await db.SaveChangesAsync();

            ev.BroadcastingRoomInstanceId = broadcast.roomInstanceId;
            await db.SaveChangesAsync();

            var host = await MatchmakingUtils.MatchmakeEvent(CreatorId, EventId);
            Assert.Equal(JoinStatus.Success, host.errorCode);
            Assert.Equal(broadcast.roomInstanceId, host.roomInstance?.roomInstanceId);

            var viewer = await MatchmakingUtils.MatchmakeEvent(InviteeId, EventId);
            Assert.Equal(JoinStatus.Success, viewer.errorCode);
            Assert.NotEqual(broadcast.roomInstanceId, viewer.roomInstance?.roomInstanceId);
            Assert.Equal(ordinary.roomInstanceId, viewer.roomInstance?.roomInstanceId);
        }
        finally
        {
            RestoreFactories(previousFactories);
        }
    }

    [Fact]
    public async Task AnInvitedViewerIsStillNotPlacedInTheBroadcastersInstance()
    {
        // An invitation grants the event, not a place in the broadcaster's own room: an invited
        // viewer is matched into an ordinary instance exactly like an uninvited one.
        var (db, previousFactories) = await CreateContextAsync();
        await using var disposeDb = db;
        try
        {
            var ev = await SeedEventAsync(db, Accessibility.Public, Accessibility.Public);
            ev.IsMultiInstance = true;
            db.PlayerEventResponses.Add(new PlayerEventResponse
            {
                PlayerEventId = EventId, PlayerId = InviteeId, Type = EventResponses.Yes
            });

            var ordinary = new RoomInstance { roomInstanceId = 500, roomId = RoomId, subRoomId = 1, eventId = EventId, maxCapacity = 8 };
            var broadcast = new RoomInstance { roomInstanceId = 501, roomId = RoomId, subRoomId = 1, eventId = EventId, maxCapacity = 8 };
            db.RoomInstances.AddRange(ordinary, broadcast);
            await db.SaveChangesAsync();

            ev.BroadcastingRoomInstanceId = broadcast.roomInstanceId;
            await db.SaveChangesAsync();

            var match = await MatchmakingUtils.MatchmakeEvent(InviteeId, EventId);

            Assert.Equal(JoinStatus.Success, match.errorCode);
            Assert.Equal(ordinary.roomInstanceId, match.roomInstance?.roomInstanceId);
            Assert.NotEqual(broadcast.roomInstanceId, match.roomInstance?.roomInstanceId);
        }
        finally
        {
            RestoreFactories(previousFactories);
        }
    }

    [Fact]
    public async Task AViewerGetsTheirOwnInstanceWhenTheBroadcastIsTheOnlyOne()
    {
        // With nothing else to share, the viewer is given a fresh instance of the event's room -
        // the broadcast instance is never reused - and it is public, so the next viewer lands
        // beside them instead of causing a third instance.
        var (db, previousFactories) = await CreateContextAsync();
        await using var disposeDb = db;
        try
        {
            var ev = await SeedEventAsync(db, Accessibility.Public, Accessibility.Public);
            ev.IsMultiInstance = true;
            db.Presences.Add(new RealPresence { playerId = StrangerId, isOnline = true });

            var broadcast = new RoomInstance { roomInstanceId = 501, roomId = RoomId, subRoomId = 1, eventId = EventId, maxCapacity = 8 };
            db.RoomInstances.Add(broadcast);
            await db.SaveChangesAsync();

            ev.BroadcastingRoomInstanceId = broadcast.roomInstanceId;
            await db.SaveChangesAsync();

            var first = await MatchmakingUtils.MatchmakeEvent(InviteeId, EventId);

            Assert.Equal(JoinStatus.Success, first.errorCode);
            Assert.NotNull(first.roomInstance);
            Assert.NotEqual(broadcast.roomInstanceId, first.roomInstance!.roomInstanceId);
            Assert.Equal(EventId, first.roomInstance.eventId);
            Assert.False(first.roomInstance.isPrivate);

            var second = await MatchmakingUtils.MatchmakeEvent(StrangerId, EventId);

            Assert.Equal(JoinStatus.Success, second.errorCode);
            Assert.Equal(first.roomInstance.roomInstanceId, second.roomInstance?.roomInstanceId);
        }
        finally
        {
            RestoreFactories(previousFactories);
        }
    }

    [Fact]
    public async Task AViewerIsNotPlacedWithTheBroadcasterWhenTheRegisteredInstanceIsStale()
    {
        // Re-entering the event hands the broadcaster a fresh instance and nothing re-registers
        // it, so the id the event still carries can name a room nobody is in. The instance the
        // broadcaster is actually standing in is off-limits for the same reason the registered
        // one is - otherwise the protection lapses the first time they walk back in.
        var (db, previousFactories) = await CreateContextAsync();
        await using var disposeDb = db;
        try
        {
            var ev = await SeedEventAsync(db, Accessibility.Public, Accessibility.Public);
            ev.IsMultiInstance = true;

            var registered = new RoomInstance { roomInstanceId = 501, roomId = RoomId, subRoomId = 1, eventId = EventId, maxCapacity = 8 };
            var standingIn = new RoomInstance { roomInstanceId = 502, roomId = RoomId, subRoomId = 1, eventId = EventId, maxCapacity = 8 };
            db.RoomInstances.AddRange(registered, standingIn);
            await db.SaveChangesAsync();

            ev.BroadcastingRoomInstanceId = registered.roomInstanceId;
            // The broadcaster has since re-entered the event: their presence names 502 while the
            // event still advertises the instance they registered, 501.
            db.Presences.Single(x => x.playerId == CreatorId).roomInstance = standingIn.roomInstanceId;
            await db.SaveChangesAsync();

            var viewer = await MatchmakingUtils.MatchmakeEvent(InviteeId, EventId);

            Assert.Equal(JoinStatus.Success, viewer.errorCode);
            Assert.NotNull(viewer.roomInstance);
            Assert.NotEqual(registered.roomInstanceId, viewer.roomInstance!.roomInstanceId);
            Assert.NotEqual(standingIn.roomInstanceId, viewer.roomInstance.roomInstanceId);
            Assert.Equal(EventId, viewer.roomInstance.eventId);
        }
        finally
        {
            RestoreFactories(previousFactories);
        }
    }

    [Fact]
    public async Task CreatorCanJoinOwnEventLongBeforeItStarts()
    {
        // The host walks into their own event whenever they want, so the room they are
        // advertising is already stood up (and they can be standing in it) hours early.
        var (db, previousFactories) = await CreateContextAsync();
        await using var disposeDb = db;
        try
        {
            var ev = await SeedEventAsync(db);
            ev.StartTime = DateTime.UtcNow.AddHours(6);
            ev.EndTime = DateTime.UtcNow.AddHours(7);
            await db.SaveChangesAsync();

            var match = await MatchmakingUtils.MatchmakeEvent(CreatorId, EventId);

            Assert.Equal(JoinStatus.Success, match.errorCode);
            Assert.Equal(EventId, match.roomInstance?.eventId);
        }
        finally
        {
            RestoreFactories(previousFactories);
        }
    }

    [Fact]
    public async Task NonCreatorIsStillHeldToTheEventStartTime()
    {
        // The early gate is the host's alone. An invited guest who shows up before the
        // start time is turned away rather than dropped into an event that has not begun.
        var (db, previousFactories) = await CreateContextAsync();
        await using var disposeDb = db;
        try
        {
            var ev = await SeedEventAsync(db, Accessibility.Public, Accessibility.Public);
            ev.StartTime = DateTime.UtcNow.AddHours(6);
            ev.EndTime = DateTime.UtcNow.AddHours(7);
            await db.SaveChangesAsync();

            var match = await MatchmakingUtils.MatchmakeEvent(InviteeId, EventId);

            Assert.Equal(JoinStatus.EventNotStarted, match.errorCode);
        }
        finally
        {
            RestoreFactories(previousFactories);
        }
    }

    [Fact]
    public async Task CreatorCannotJoinAnEventThatHasAlreadyFinished()
    {
        // The exemption opens the door early, not indefinitely: once the window closes the
        // event is closed to its own creator too.
        var (db, previousFactories) = await CreateContextAsync();
        await using var disposeDb = db;
        try
        {
            var ev = await SeedEventAsync(db);
            ev.StartTime = DateTime.UtcNow.AddHours(-2);
            ev.EndTime = DateTime.UtcNow.AddHours(-1);
            await db.SaveChangesAsync();

            var match = await MatchmakingUtils.MatchmakeEvent(CreatorId, EventId);

            Assert.Equal(JoinStatus.EventAlreadyFinished, match.errorCode);
        }
        finally
        {
            RestoreFactories(previousFactories);
        }
    }

    [Theory]
    [InlineData(false, 3)]
    [InlineData(true, 6)]
    public async Task EventInstanceWireTypeMatchesMultiInstanceSetting(bool multiInstance, int wireType)
    {
        var (db, previousFactories) = await CreateContextAsync();
        await using var disposeDb = db;
        try
        {
            var ev = await SeedEventAsync(db, Accessibility.Public, Accessibility.Public);
            ev.IsMultiInstance = multiInstance;
            db.RoomInstances.Add(new RoomInstance
            {
                roomInstanceId = 501, roomId = RoomId, subRoomId = 1,
                eventId = EventId, maxCapacity = 8,
                roomInstanceType = RadicadeServer.RecNet.Enums.Rooms.RoomInstanceType.Event
            });
            await db.SaveChangesAsync();

            // Reusing a room created before multi-instance was enabled must repair its type.
            var existing = await MatchmakingUtils.MatchmakeEvent(CreatorId, EventId);
            Assert.Equal(JoinStatus.Success, existing.errorCode);
            Assert.Equal(501, existing.roomInstance!.roomInstanceId);
            Assert.Equal(wireType, (int)existing.roomInstance.roomInstanceType);
            db.ChangeTracker.Clear();
            Assert.Equal(wireType, (int)(await db.RoomInstances.SingleAsync()).roomInstanceType);

            // Fresh private event instances need the same type; privacy is a separate flag.
            var created = await MatchmakingUtils.MatchmakeEvent(CreatorId, EventId, JoinMode.PrivateNewInstance);
            Assert.Equal(JoinStatus.Success, created.errorCode);
            Assert.True(created.roomInstance!.isPrivate);
            var json = System.Text.Json.JsonSerializer.SerializeToElement(created.roomInstance);
            Assert.Equal(wireType, json.GetProperty("roomInstanceType").GetInt32());
        }
        finally { RestoreFactories(previousFactories); }
    }

    [Theory]
    [InlineData(false)]
    [InlineData(true)]
    public async Task PrivateModeOnAnEventCreatesThePlayersOwnPrivateInstance(bool sourceStillOccupied)
    {
        // PRIVATE MODE on the event screen asks for the player's own copy of the event's
        // room. It has to be created even while the event has a shared instance and a live
        // broadcast instance to hand out - and it must be neither of those, or pressing the
        // button would move the player into somebody else's room.
        var (db, previousFactories) = await CreateContextAsync();
        await using var disposeDb = db;
        try
        {
            var ev = await SeedEventAsync(db, Accessibility.Public, Accessibility.Public);
            ev.IsMultiInstance = true;

            var shared = new RoomInstance { roomInstanceId = 501, roomId = RoomId, subRoomId = 1, eventId = EventId, maxCapacity = 8 };
            var broadcast = new RoomInstance { roomInstanceId = 502, roomId = RoomId, subRoomId = 1, eventId = EventId, maxCapacity = 8 };
            db.RoomInstances.AddRange(shared, broadcast);
            await db.SaveChangesAsync();
            ev.BroadcastingRoomInstanceId = broadcast.roomInstanceId;
            if (sourceStillOccupied)
            {
                var presenter = await db.Presences.SingleAsync(p => p.playerId == InviteeId);
                presenter.isOnline = true;
                presenter.roomInstance = broadcast.roomInstanceId;
            }
            await db.SaveChangesAsync();

            var match = await MatchmakingUtils.MatchmakeEvent(
                CreatorId, EventId, JoinMode.PrivateNewInstance);

            Assert.Equal(JoinStatus.Success, match.errorCode);
            Assert.NotNull(match.roomInstance);
            Assert.NotEqual(shared.roomInstanceId, match.roomInstance.roomInstanceId);
            Assert.NotEqual(broadcast.roomInstanceId, match.roomInstance.roomInstanceId);
            Assert.Equal(EventId, match.roomInstance.eventId);
            // Event rooms stay event instances; `isPrivate` is what makes this one the
            // player's own.
            Assert.True(match.roomInstance.isPrivate);
            // Matchmaking joined the player through its own context, so read the presence back
            // fresh rather than through this context's tracked copy.
            db.ChangeTracker.Clear();
            Assert.Equal(sourceStillOccupied ? (long?)broadcast.roomInstanceId : null,
                (await db.PlayerEvents.SingleAsync(e => e.PlayerEventId == EventId)).BroadcastingRoomInstanceId);
            Assert.Equal(match.roomInstance.roomInstanceId,
                (await db.Presences.AsNoTracking().SingleAsync(x => x.playerId == CreatorId)).roomInstance);
        }
        finally
        {
            RestoreFactories(previousFactories);
        }
    }

    [Fact]
    public async Task EachPlayersPrivateModeGetsItsOwnInstance()
    {
        // Two people pressing PRIVATE MODE on the same event do not end up together: every
        // request is a new room, so neither is handed the other's private instance.
        var (db, previousFactories) = await CreateContextAsync();
        await using var disposeDb = db;
        try
        {
            await SeedEventAsync(db, Accessibility.Public, Accessibility.Public);

            var host = await MatchmakingUtils.MatchmakeEvent(
                CreatorId, EventId, JoinMode.PrivateNewInstance);
            var guest = await MatchmakingUtils.MatchmakeEvent(
                InviteeId, EventId, JoinMode.PrivateNewInstance);

            Assert.Equal(JoinStatus.Success, host.errorCode);
            Assert.Equal(JoinStatus.Success, guest.errorCode);
            Assert.NotNull(host.roomInstance);
            Assert.NotNull(guest.roomInstance);
            Assert.True(host.roomInstance!.isPrivate);
            Assert.True(guest.roomInstance!.isPrivate);
            Assert.NotEqual(host.roomInstance.roomInstanceId, guest.roomInstance.roomInstanceId);
        }
        finally
        {
            RestoreFactories(previousFactories);
        }
    }

    [Fact]
    public async Task PrivateModeLeavesNoInstanceBehindForSomeoneWhoMayNotBeInTheRoom()
    {
        // The event's room is private and this player is not the host, not a co-owner and has
        // no invitation, so PRIVATE MODE is refused - refused before anything is created, so
        // a refused press does not leave an empty private instance in the room.
        var (db, previousFactories) = await CreateContextAsync();
        await using var disposeDb = db;
        try
        {
            await SeedEventAsync(db, Accessibility.Public, Accessibility.Private);
            db.Presences.Add(new RealPresence { playerId = StrangerId, isOnline = true });
            await db.SaveChangesAsync();
            var before = await db.RoomInstances.CountAsync();

            var match = await MatchmakingUtils.MatchmakeEvent(
                StrangerId, EventId, JoinMode.PrivateNewInstance);

            Assert.Equal(JoinStatus.RoomIsPrivate, match.errorCode);
            Assert.Equal(before, await db.RoomInstances.CountAsync());
        }
        finally
        {
            RestoreFactories(previousFactories);
        }
    }

    [Fact]
    public async Task EventRouteHonoursTheClientsPrivateMode()
    {
        // Both event routes take the same GoToRequest as every other go-to call, and the join
        // mode on it is what the event screen's PRIVATE MODE button sends. Without it the
        // route answered with a shared instance and the client waited on a private room that
        // was never created.
        var (db, previousFactories) = await CreateContextAsync();
        await using var disposeDb = db;
        try
        {
            await SeedEventAsync(db, Accessibility.Public, Accessibility.Public);
            var controller = new MatchmakingAPI(db);
            SetUser(controller, CreatorId);

            var privateJoin = await controller.GoToEvent(EventId,
                new GoToRequest { JoinMode = JoinMode.PrivateNewInstance });

            Assert.Equal(JoinStatus.Success, privateJoin!.errorCode);
            Assert.True(privateJoin.roomInstance!.isPrivate);

            // And the ordinary join is still the shared one: the private instance above is
            // never handed out by the plain lookup.
            var ordinaryJoin = await controller.GoToEvent(EventId,
                new GoToRequest { JoinMode = JoinMode.PublicMatchmaking });

            Assert.Equal(JoinStatus.Success, ordinaryJoin!.errorCode);
            Assert.False(ordinaryJoin.roomInstance!.isPrivate);
            Assert.NotEqual(privateJoin.roomInstance.roomInstanceId,
                ordinaryJoin.roomInstance.roomInstanceId);
        }
        finally
        {
            RestoreFactories(previousFactories);
        }
    }

    [Fact]
    public async Task EventParticipantsMayInviteAndAStrangerIsRefusedWithTheCreatorNamed()
    {
        // The gate used to be creator-only. The client offers the invite button to players who are
        // already on the event, so an attendee was answered an anonymous 403 for a press the client
        // had invited them to make.
        const long OutsiderId = 99;

        var (db, previousFactories) = await CreateContextAsync();
        await using var disposeDb = db;
        try
        {
            await SeedEventAsync(db);
            db.PlayerEventResponses.Add(new PlayerEventResponse
            {
                PlayerEventId = EventId,
                PlayerId = InviteeId,
                Type = EventResponses.Yes
            });
            await db.SaveChangesAsync();

            var participant = new EventsAPI(db);
            SetUser(participant, InviteeId);
            SetFormBody(participant, $"PlayerEventId={EventId}&InvitedPlayerIds%5B%5D={StrangerId}");
            Assert.IsType<OkObjectResult>(await participant.BulkInvite());
            Assert.Equal(EventResponses.Pending, (await db.PlayerEventResponses
                .SingleAsync(x => x.PlayerEventId == EventId && x.PlayerId == StrangerId)).Type);

            var outsider = new EventsAPI(db);
            SetUser(outsider, OutsiderId);
            SetFormBody(outsider, $"PlayerEventId={EventId}&InvitedPlayerIds%5B%5D={InviteeId}");

            var refused = Assert.IsType<ObjectResult>(await outsider.BulkInvite());

            Assert.Equal(StatusCodes.Status403Forbidden, refused.StatusCode);
            Assert.Contains($"\"CreatorPlayerId\":{CreatorId}", JsonSerializer.Serialize(refused.Value));
        }
        finally
        {
            RestoreFactories(previousFactories);
        }
    }

    [Fact]
    public async Task AnEventWhoseCreatorIsGoneMayBeInvitedToByAnyone()
    {
        // A wiped-and-reseeded database leaves events whose creating account no longer exists. Nobody
        // is left to invite for them, so refusing every caller made the event permanently unusable.
        var (db, previousFactories) = await CreateContextAsync();
        await using var disposeDb = db;
        try
        {
            await SeedEventAsync(db);
            var orphan = await db.PlayerEvents.SingleAsync(x => x.PlayerEventId == EventId);
            orphan.CreatorPlayerId = 987654;
            await db.SaveChangesAsync();

            var controller = new EventsAPI(db);
            SetUser(controller, StrangerId);
            SetFormBody(controller, $"PlayerEventId={EventId}&InvitedPlayerIds%5B%5D={InviteeId}");

            Assert.IsType<OkObjectResult>(await controller.BulkInvite());
        }
        finally
        {
            RestoreFactories(previousFactories);
        }
    }
}