Radicade/ServerTests/EventsApiTests.cs

using System.IO;
using System.Security.Claims;
using System.Text;
using Microsoft.AspNetCore.Http;
using Microsoft.AspNetCore.Mvc;
using Microsoft.EntityFrameworkCore;
using RadicadeServer.API.Events;
using RadicadeServer.DB;
using RadicadeServer.RecNet.Enums;
using RadicadeServer.RecNet.Events;
using RadicadeServer.RecNet.Rooms;
using Xunit;

namespace RadicadeServer.Tests;

/// <summary>
/// End-to-end tests for the game's event endpoints, exercising the real
/// EventsAPI controller against an in-memory database.
/// </summary>
public class EventsApiTests
{
    private const long CreatorId = 42;

    private static RecDBContext CreateDb()
    {
        var options = TestDbOptions.Create()
            .UseInMemoryDatabase(Guid.NewGuid().ToString())
            .Options;
        return new RecDBContext(options);
    }

    private static EventsAPI CreateController(RecDBContext db, long? userId = CreatorId)
    {
        var identity = new ClaimsIdentity("TestAuth");
        if (userId.HasValue)
            identity.AddClaim(new Claim(ClaimTypes.NameIdentifier, userId.Value.ToString()));

        return new EventsAPI(db)
        {
            ControllerContext = new ControllerContext
            {
                HttpContext = new DefaultHttpContext { User = new ClaimsPrincipal(identity) }
            }
        };
    }

    private static EventsAPI CreateController(RecDBContext db, long? userId, string jsonBody)
    {
        var controller = CreateController(db, userId);
        SetJsonBody(controller, jsonBody);
        return controller;
    }

    private static void SetJsonBody(EventsAPI controller, string jsonBody)
    {
        var bytes = Encoding.UTF8.GetBytes(jsonBody);
        controller.HttpContext.Request.Body = new MemoryStream(bytes);
        controller.HttpContext.Request.ContentType = "application/json";
        controller.HttpContext.Request.ContentLength = bytes.Length;
    }

    private static async Task<long> CreateV2EventAsync(RecDBContext db, long roomId)
    {
        var createController = CreateController(
            db, CreatorId,
            $$"""{ "Name": "Club meetup", "RoomId": {{roomId}} }""");
        var create = Assert.IsType<OkObjectResult>(await createController.CreateEventV2());
        using var document = System.Text.Json.JsonDocument.Parse(
            System.Text.Json.JsonSerializer.Serialize(create.Value));
        return document.RootElement.GetProperty("PlayerEvent").GetProperty("PlayerEventId").GetInt64();
    }

    private static async Task<System.Text.Json.JsonDocument> UpdateEventV2Async(
        RecDBContext db, long eventId, string route, string body)
    {
        var controller = CreateController(db);
        SetJsonBody(controller, body);
        controller.HttpContext.Request.Path = $"/api/playerevents/v2/{eventId}/{route}";
        var result = Assert.IsType<OkObjectResult>(await controller.UpdateEventV2(eventId));
        return System.Text.Json.JsonDocument.Parse(System.Text.Json.JsonSerializer.Serialize(result.Value));
    }

    private static async Task<long> SeedRoomAsync(RecDBContext db, string name = "Test Room")
    {
        var room = new RoomData { Name = name };
        db.Rooms.Add(room);
        await db.SaveChangesAsync();
        return room.RoomId;
    }

    private static async Task<PlayerEvent> CreateEventAsync(
        EventsAPI controller,
        long roomId,
        string name = "Launch Party")
    {
        var result = await controller.CreateEvent(
            name, "A test event", roomId,
            DateTime.UtcNow.AddHours(1), null, null, null);

        var ok = Assert.IsType<OkObjectResult>(result.Result);
        return Assert.IsType<PlayerEvent>(ok.Value);
    }

    [Fact]
    public async Task CreateEvent_ThenAppearsInSearchAndRoomEvents()
    {
        var db = CreateDb();
        var controller = CreateController(db);
        var roomId = await SeedRoomAsync(db);

        var created = await CreateEventAsync(controller, roomId, "Launch Party");		var search = await controller.SearchEvents("launch", null);
		Assert.Single(search);
		Assert.Contains(search, e => e.PlayerEventId == created.PlayerEventId);

        var roomEvents = await controller.GetEventsInRoom(roomId);
        Assert.Contains(roomEvents, e => e.PlayerEventId == created.PlayerEventId);
    }

    [Fact]
    public async Task SearchEvents_OnlyReturnsPublicUpcomingEvents()
    {
        var db = CreateDb();
        var controller = CreateController(db);
        var roomId = await SeedRoomAsync(db);

        await CreateEventAsync(controller, roomId, "Public Upcoming");
        db.PlayerEvents.Add(new PlayerEventDB
        {
            Name = "Ended",
            Description = "",
            ImageName = "",
            StartTime = DateTime.UtcNow.AddHours(-4),
            EndTime = DateTime.UtcNow.AddHours(-2),
            CreatorPlayerId = CreatorId,
            AttendeeCount = 1,
            RoomId = roomId,
            Accessibility = Accessibility.Public
        });
        db.PlayerEvents.Add(new PlayerEventDB
        {
            Name = "Private",
            Description = "",
            ImageName = "",
            StartTime = DateTime.UtcNow.AddHours(1),
            EndTime = DateTime.UtcNow.AddHours(3),
            CreatorPlayerId = CreatorId,
            AttendeeCount = 1,
            RoomId = roomId,
            Accessibility = Accessibility.Private
        });
        await db.SaveChangesAsync();		var search = await controller.SearchEvents(null, null);
		Assert.Single(search);
		Assert.Equal("Public Upcoming", search[0].Name);
    }

    [Fact]
    public async Task CreateEvent_BlankName_ReturnsBadRequest()
    {
        var db = CreateDb();
        var controller = CreateController(db);
        var roomId = await SeedRoomAsync(db);

        var result = await controller.CreateEvent("   ", null, roomId, null, null, null, null);

        Assert.IsType<BadRequestObjectResult>(result.Result);
    }

    [Fact]
    public async Task CreateEvent_NonPositiveRoomId_ReturnsBadRequest()
    {
        var db = CreateDb();
        var controller = CreateController(db);

        var result = await controller.CreateEvent("Launch", null, 0, null, null, null, null);

        Assert.IsType<BadRequestObjectResult>(result.Result);
    }

    [Fact]
    public async Task CreateEvent_UnknownRoom_ReturnsBadRequest()
    {
        var db = CreateDb();
        var controller = CreateController(db);

        var result = await controller.CreateEvent("Launch", null, 9999, null, null, null, null);

        Assert.IsType<BadRequestObjectResult>(result.Result);
    }

    [Fact]
    public async Task CreateEvent_NoUser_ReturnsUnauthorized()
    {
        var db = CreateDb();
        var controller = CreateController(db, userId: null);
        var roomId = await SeedRoomAsync(db);

        var result = await controller.CreateEvent("Launch", null, roomId, null, null, null, null);

        Assert.IsType<UnauthorizedResult>(result.Result);
    }

    [Fact]
    public async Task CreateEvent_ImplicitlyRSVPsCreatorYes()
    {
        var db = CreateDb();
        var controller = CreateController(db);
        var roomId = await SeedRoomAsync(db);

        var created = await CreateEventAsync(controller, roomId);

        var response = await db.PlayerEventResponses
            .SingleAsync(r => r.PlayerEventId == created.PlayerEventId);
        Assert.Equal(CreatorId, response.PlayerId);
        Assert.Equal(EventResponses.Yes, response.Type);
        Assert.Equal(1, created.AttendeeCount);
    }

    [Fact]
    public async Task GetCreatedEvents_ReturnsOnlyTheUsersEvents()
    {
        var db = CreateDb();
        var controller = CreateController(db, userId: 42);
        var otherController = CreateController(db, userId: 43);
        var roomId = await SeedRoomAsync(db);

        await CreateEventAsync(controller, roomId, "Mine");
        await CreateEventAsync(otherController, roomId, "Theirs");

        var mine = await controller.GetCreatedEvents();

        Assert.Single(mine);
        Assert.Equal("Mine", mine[0].Name);
    }

    [Fact]
    public async Task GetAllEvents_ReturnsCreatedAndNoWireResponses()
    {
        var db = CreateDb();
        var controller = CreateController(db);
        var roomId = await SeedRoomAsync(db);
        await CreateEventAsync(controller, roomId, "Mine");

        var all = await controller.GetAllEvents();

        Assert.Single(all.Created);
        // The 2023 client parses Responses entries with its typed MessagePack
        // deserializer and a shape it does not fully understand deserializes to
        // null, failing the boot-time events refresh. The RecFlare reference
        // server always serves an empty Responses list, so Radicade does too.
        Assert.Empty(all.Responses);
    }

    [Fact]
    public async Task GetAllEvents_NeverServesAnEmptyImageName()
    {
        var db = CreateDb();
        var controller = CreateController(db);
        var roomId = await SeedRoomAsync(db);
        db.PlayerEvents.Add(new PlayerEventDB
        {
            Name = "No image",
            Description = "",
            ImageName = "",
            StartTime = DateTime.UtcNow.AddHours(1),
            EndTime = DateTime.UtcNow.AddHours(2),
            CreatorPlayerId = CreatorId,
            AttendeeCount = 0,
            RoomId = roomId,
            Accessibility = Accessibility.Public
        });
        await db.SaveChangesAsync();

        var all = await controller.GetAllEvents();
        var created = Assert.Single(all.Created);

        // The 2023 client's RRUI events cache resolves an image for every event it
        // lists and throws on an empty name before making any request, which fails
        // the whole refresh and makes the client retry it in a tight loop.
        Assert.Equal("default", created.ImageName);
    }

    [Fact]
    public async Task ClubEventFeedsReturnTheExpectedDifferentShapes()
    {
        var db = CreateDb();
        var controller = CreateController(db);
        var roomId = await SeedRoomAsync(db);
        var now = DateTime.UtcNow;
        db.PlayerEvents.AddRange(
            new PlayerEventDB
            {
                Name = "Club 12 event", Description = "", ImageName = "", RoomId = roomId,
                CreatorPlayerId = CreatorId, StartTime = now.AddHours(1), EndTime = now.AddHours(2),
                ClubId = 12, Accessibility = Accessibility.Public
            },
            new PlayerEventDB
            {
                Name = "Club 13 event", Description = "", ImageName = "", RoomId = roomId,
                CreatorPlayerId = CreatorId, StartTime = now.AddHours(2), EndTime = now.AddHours(3),
                ClubId = 13, Accessibility = Accessibility.Public
            },
            new PlayerEventDB
            {
                Name = "Unattached event", Description = "", ImageName = "", RoomId = roomId,
                CreatorPlayerId = CreatorId, StartTime = now.AddHours(3), EndTime = now.AddHours(4),
                Accessibility = Accessibility.Public
            });
        await db.SaveChangesAsync();

        var clubs = await controller.GetEventsByClubs([12, 13]);
        Assert.Equal(new[] { "Club 12 event", "Club 13 event" }, clubs.Select(e => e.Name));
        Assert.Equal(12, clubs[0].ClubId);

        var single = Assert.IsType<OkObjectResult>(await controller.GetEventsByClub(12));
        using var json = System.Text.Json.JsonDocument.Parse(System.Text.Json.JsonSerializer.Serialize(single.Value));
        Assert.Equal(string.Empty, json.RootElement.GetProperty("ContinuationToken").GetString());
        Assert.Equal("Club 12 event", json.RootElement.GetProperty("Events")[0].GetProperty("Name").GetString());
    }

    [Fact]
    public async Task GetEvent_ReturnsEventOrNotFound()
    {
        var db = CreateDb();
        var controller = CreateController(db);
        var roomId = await SeedRoomAsync(db);
        var created = await CreateEventAsync(controller, roomId);

        var found = await controller.GetEvent(created.PlayerEventId);
        var ok = Assert.IsType<OkObjectResult>(found.Result);
        Assert.Equal(created.PlayerEventId, Assert.IsType<PlayerEvent>(ok.Value).PlayerEventId);

        var missing = await controller.GetEvent(9999);
        Assert.IsType<NotFoundResult>(missing.Result);
    }

    [Fact]
    public async Task GetEvent_SerializesAllClientRequiredFields()
    {
        // The client deserializes every key of its PlayerEvent model and logs
        // "Failed to find key 'Tags'" (then "Malformed Response") when one is
        // missing. Guard the full wire shape here.
        var db = CreateDb();
        var controller = CreateController(db);
        var roomId = await SeedRoomAsync(db);
        var created = await CreateEventAsync(controller, roomId);

        var json = System.Text.Json.JsonSerializer.Serialize(created);

        Assert.Contains("\"Tags\"", json);
        Assert.Contains("\"ClubId\"", json);
        Assert.Contains("\"State\"", json);
        Assert.Contains("\"CreatedAt\"", json);
    }

    [Fact]
    public void GetEventTagFilters_ReturnsUsableTagCatalog()
    {
        // The client refuses to save an event while every tag group is empty, so the
        // endpoint serves the reference server's lowercase catalog instead of three
        // empty sets. TrendingFilters is null exactly as the reference serves it -
        // the client renders no trending row for null.
        var db = CreateDb();
        var controller = CreateController(db);

        var filters = controller.GetEventTagFilters();

        Assert.NotNull(filters.PinnedFilters);
        Assert.NotNull(filters.PopularFilters);
        Assert.Null(filters.TrendingFilters);
        Assert.NotEmpty(filters.PinnedFilters);
        Assert.NotEmpty(filters.PopularFilters);
        Assert.All(filters.PinnedFilters, t => Assert.Equal(t, t.ToLowerInvariant()));
        Assert.All(filters.PopularFilters, t => Assert.Equal(t, t.ToLowerInvariant()));
        Assert.Contains("game", filters.PopularFilters);
        Assert.Contains("meetup", filters.PinnedFilters);
    }

    [Fact]
    public async Task SetResponse_AddsRsvpAndUpdatesAttendeeCount()
    {
        var db = CreateDb();
        var creator = CreateController(db, userId: 42);
        var guest = CreateController(db, userId: 43);
        var roomId = await SeedRoomAsync(db);
        var created = await CreateEventAsync(creator, roomId);

        var yes = await guest.SetResponse(created.PlayerEventId, EventResponses.Yes);
        Assert.Equal(
            EventResponses.Yes,
            Assert.IsType<EventResponse>(Assert.IsType<OkObjectResult>(yes.Result).Value).Type);

        var ev = await db.PlayerEvents.SingleAsync(e => e.PlayerEventId == created.PlayerEventId);
        Assert.Equal(2, ev.AttendeeCount);

        await guest.SetResponse(created.PlayerEventId, EventResponses.No);
        ev = await db.PlayerEvents.SingleAsync(e => e.PlayerEventId == created.PlayerEventId);
        Assert.Equal(1, ev.AttendeeCount);
    }

    [Fact]
    public void GetLegacyPlaceholderResponses_ReturnsAnEmptyList()
    {
        var controller = CreateController(CreateDb());
        var route = typeof(EventsAPI).GetMethod(nameof(EventsAPI.GetLegacyPlaceholderResponses))!
            .GetCustomAttributes(typeof(Microsoft.AspNetCore.Mvc.HttpGetAttribute), false)
            .Cast<Microsoft.AspNetCore.Mvc.HttpGetAttribute>()
            .Single();
        Assert.Equal("v1/-1/responses", route.Template);

        var responses = Assert.IsType<OkObjectResult>(controller.GetLegacyPlaceholderResponses());
        var list = Assert.IsAssignableFrom<IEnumerable<RadicadeServer.RecNet.Events.EventResponse>>(responses.Value);
        Assert.Empty(list);
    }

    [Fact]
    public async Task GetResponsesAndAttendees_ReflectRsvps()
    {
        var db = CreateDb();
        var creator = CreateController(db, userId: 42);
        var guest = CreateController(db, userId: 43);
        var roomId = await SeedRoomAsync(db);
        var created = await CreateEventAsync(creator, roomId);
        await guest.SetResponse(created.PlayerEventId, EventResponses.Yes);

        var responses = await creator.GetResponses(created.PlayerEventId);
        var list = Assert.IsType<List<EventResponse>>(
            Assert.IsType<OkObjectResult>(responses.Result).Value);
        Assert.Equal(2, list.Count);

        var attendees = await creator.GetAttendees(created.PlayerEventId);
        var ids = Assert.IsType<List<long>>(
            Assert.IsType<OkObjectResult>(attendees.Result).Value);
        Assert.Contains(CreatorId, ids);
        Assert.Contains(43, ids);
    }

    [Fact]
    public async Task DeleteEvent_CreatorCanDelete_NonCreatorCannot()
    {
        var db = CreateDb();
        var creator = CreateController(db, userId: 42);
        var stranger = CreateController(db, userId: 99);
        var roomId = await SeedRoomAsync(db);
        var created = await CreateEventAsync(creator, roomId);

        var forbidden = await stranger.DeleteEvent(created.PlayerEventId);
        Assert.IsType<ForbidResult>(forbidden);
        Assert.NotNull(await db.PlayerEvents.FindAsync(created.PlayerEventId));

        var ok = await creator.DeleteEvent(created.PlayerEventId);
        Assert.IsType<OkResult>(ok);
        Assert.Null(await db.PlayerEvents.FindAsync(created.PlayerEventId));
        Assert.Empty(await db.PlayerEventResponses
            .Where(r => r.PlayerEventId == created.PlayerEventId).ToListAsync());
    }

    [Fact]
    public async Task DeleteEvent_MissingEvent_ReturnsNotFound()
    {
        var db = CreateDb();
        var controller = CreateController(db);

        var result = await controller.DeleteEvent(9999);

        Assert.IsType<NotFoundResult>(result);
    }

    [Fact]
    public async Task CreateEventV2_CreatesEventAndReturnsWrapper()
    {
        var db = CreateDb();
        var roomId = await SeedRoomAsync(db);
        var body =
            $$"""
            {
                "Name": "Launch Party",
                "Description": "Big launch",
                "RoomId": {{roomId}},
                "StartTime": "{{DateTime.UtcNow.AddHours(1):o}}",
                "EndTime": "{{DateTime.UtcNow.AddHours(3):o}}",
                "Accessibility": "public",
                "SubRoomId": null,
                "ImageName": ""
            }
            """;
        var controller = CreateController(db, CreatorId, body);

        var result = await controller.CreateEventV2();

        var ok = Assert.IsType<OkObjectResult>(result);
        var json = System.Text.Json.JsonSerializer.Serialize(ok.Value);
        using var doc = System.Text.Json.JsonDocument.Parse(json);

        // The write envelope: { PlayerEvent, Result, TagModifyResult } (the shape the
        // reference server answers and the client's typed deserializer requires).
        Assert.Equal(0, doc.RootElement.GetProperty("Result").GetInt32());
        var tagModify = doc.RootElement.GetProperty("TagModifyResult");
        Assert.Equal(0, tagModify.GetProperty("Result").GetInt32());
        Assert.Equal(System.Text.Json.JsonValueKind.Array, tagModify.GetProperty("Tags").ValueKind);

        var created = doc.RootElement.GetProperty("PlayerEvent");
        Assert.Equal("Launch Party", created.GetProperty("Name").GetString());
        Assert.Equal(roomId, created.GetProperty("RoomId").GetInt64());
        Assert.Equal(Accessibility.Public, (Accessibility)created.GetProperty("Accessibility").GetInt32());

        var eventId = created.GetProperty("PlayerEventId").GetInt64();
        var ev = await db.PlayerEvents.SingleAsync(e => e.PlayerEventId == eventId);
        Assert.Equal(1, ev.AttendeeCount);
        var rsvp = await db.PlayerEventResponses.SingleAsync(r => r.PlayerEventId == eventId);
        Assert.Equal(CreatorId, rsvp.PlayerId);
        Assert.Equal(EventResponses.Yes, rsvp.Type);
    }

    [Fact]
    public async Task CreateEventV2_UnknownRoom_ReturnsBadRequest()
    {
        var db = CreateDb();
        var body = """{ "Name": "Launch", "RoomId": 9999 }""";
        var controller = CreateController(db, CreatorId, body);

        var result = await controller.CreateEventV2();

        Assert.IsType<BadRequestObjectResult>(result);
    }

    [Fact]
    public async Task UpdateEventV2StoresClubAndEventSettings()
    {
        var db = CreateDb();
        var roomId = await SeedRoomAsync(db);
        var eventId = await CreateV2EventAsync(db, roomId);
        var payload = """{ "ClubId": 27 }""";

        using var updatedJson = await UpdateEventV2Async(db, eventId, "club", payload);
        var playerEvent = updatedJson.RootElement.GetProperty("PlayerEvent");
        Assert.Equal(27, playerEvent.GetProperty("ClubId").GetInt64());
        Assert.False(playerEvent.GetProperty("IsMultiInstance").GetBoolean());

        var routeAttributes = typeof(EventsAPI).GetMethod(nameof(EventsAPI.UpdateEventV2))!
            .GetCustomAttributes(typeof(Microsoft.AspNetCore.Mvc.Routing.HttpMethodAttribute), false)
            .Cast<Microsoft.AspNetCore.Mvc.Routing.HttpMethodAttribute>();
        Assert.Contains(routeAttributes, attribute => attribute.Template == "v2/{eventId:long}/club");
    }

    [Fact]
    public async Task UpdateEventV2ClubRouteSupportsNullableClubId()
    {
        var db = CreateDb();
        var roomId = await SeedRoomAsync(db);
        var eventId = await CreateV2EventAsync(db, roomId);

        using var assigned = await UpdateEventV2Async(db, eventId, "club", """{ "ClubId": 27 }""");
        using var cleared = await UpdateEventV2Async(db, eventId, "club", """{ "ClubId": null }""");

        Assert.Equal(27, assigned.RootElement.GetProperty("PlayerEvent").GetProperty("ClubId").GetInt64());
        Assert.Equal(System.Text.Json.JsonValueKind.Null,
            cleared.RootElement.GetProperty("PlayerEvent").GetProperty("ClubId").ValueKind);
    }

    [Fact]
    public async Task UpdateEventV2MultiInstanceRouteReadsItsFocusedPayload()
    {
        var db = CreateDb();
        var roomId = await SeedRoomAsync(db);
        var eventId = await CreateV2EventAsync(db, roomId);
        var body = """{ "IsMultiInstance": true, "SupportMultiInstanceRoomChat": true, "DefaultBroadcastPermissions": 3, "CanRequestBroadcastPermissions": 7 }""";

        using var updated = await UpdateEventV2Async(db, eventId, "multiinstance", body);
        var playerEvent = updated.RootElement.GetProperty("PlayerEvent");
        Assert.True(playerEvent.GetProperty("IsMultiInstance").GetBoolean());
        Assert.True(playerEvent.GetProperty("SupportMultiInstanceRoomChat").GetBoolean());
        Assert.Equal(3, playerEvent.GetProperty("DefaultBroadcastPermissions").GetInt32());
        Assert.Equal(7, playerEvent.GetProperty("CanRequestBroadcastPermissions").GetInt32());
    }

    [Fact]
    public async Task UpdateEventV2StoresStructuredTagsInTheClientShape()
    {
        var db = CreateDb();
        var roomId = await SeedRoomAsync(db);
        var eventId = await CreateV2EventAsync(db, roomId);
        var body = """{ "Tags": [{ "Tag": "meetup", "Type": 1 }] }""";

        using var updated = await UpdateEventV2Async(db, eventId, "tags", body);
        var tag = updated.RootElement.GetProperty("PlayerEvent").GetProperty("Tags")[0];
        Assert.Equal("meetup", tag.GetProperty("Tag").GetString());
        Assert.Equal(1, tag.GetProperty("Type").GetInt32());
        Assert.Equal("[{\"Tag\":\"meetup\",\"Type\":1}]",
            (await db.PlayerEvents.SingleAsync(x => x.PlayerEventId == eventId)).TagsJson);
    }

    [Fact]
    public async Task DeleteEventV2_RemovesTheEvent()
    {
        var db = CreateDb();
        var roomId = await SeedRoomAsync(db);
        var controller = CreateController(
            db, CreatorId, $$"""{ "Name": "To Delete", "RoomId": {{roomId}} }""");

        var create = await controller.CreateEventV2();
        long createdId;
        using (var doc = System.Text.Json.JsonDocument.Parse(
            System.Text.Json.JsonSerializer.Serialize(Assert.IsType<OkObjectResult>(create).Value)))
            createdId = doc.RootElement.GetProperty("PlayerEvent").GetProperty("PlayerEventId").GetInt64();

        var delete = await controller.DeleteEventV2(createdId);

        Assert.IsType<OkObjectResult>(delete);
        Assert.Null(await db.PlayerEvents.FindAsync(createdId));
        Assert.Empty(await db.PlayerEventResponses
            .Where(r => r.PlayerEventId == createdId).ToListAsync());
    }

    [Fact]
    public async Task DeleteEventV2_AlreadyGoneEvent_AnswersSuccessInsteadOfNotFound()
    {
        // The client clears a card only when the 82 frame says so, so a list still showing an
        // event whose row is gone is otherwise stuck: every retry is a 404 it can only render as
        // an error and no frame is ever pushed again. A repeat delete answers success and puts
        // the frame back on the wire, which is what lets the retry clear the card.
        var db = CreateDb();
        var controller = CreateController(db);

        var result = await controller.DeleteEventV2(9999);

        var ok = Assert.IsType<OkObjectResult>(result);
        using var document = System.Text.Json.JsonDocument.Parse(
            System.Text.Json.JsonSerializer.Serialize(ok.Value));
        Assert.Equal(0, document.RootElement.GetProperty("Result").GetInt32());
        Assert.Equal(9999,
            document.RootElement.GetProperty("PlayerEvent").GetProperty("PlayerEventId").GetInt64());
    }

    [Fact]
    public async Task DeleteEventV2_OtherPlayersEvent_IsStillForbidden()
    {
        // Answering "already gone" must not widen who may delete a row that is still there.
        var db = CreateDb();
        var roomId = await SeedRoomAsync(db);
        var createdId = await CreateV2EventAsync(db, roomId);

        var stranger = CreateController(db, userId: 99);
        Assert.IsType<ForbidResult>(await stranger.DeleteEventV2(createdId));
        Assert.NotNull(await db.PlayerEvents.FindAsync(createdId));
    }

    private static async Task<long> MakeMultiInstanceAsync(RecDBContext db, long eventId)
    {
        using var updated = await UpdateEventV2Async(
            db, eventId, "multiinstance", """{ "IsMultiInstance": true }""");
        return eventId;
    }

    [Fact]
    public async Task BroadcastRoomInstance_SetsAndClearsTheBroadcastingInstance()
    {
        // The client posts `BroadcastRoomInstanceRequest { PlayerEventId, RoomInstanceId }`
        // to api/playerevents/v1/broadcast when a broadcaster goes live, and again with a
        // null instance when they stop. The server never had the route, so the call 404ed.
        var db = CreateDb();
        var roomId = await SeedRoomAsync(db);
        var eventId = await MakeMultiInstanceAsync(db, await CreateV2EventAsync(db, roomId));
        var instance = new RoomInstance { roomId = roomId, subRoomId = 1, eventId = eventId };
        db.RoomInstances.Add(instance);
        await db.SaveChangesAsync();

        var start = CreateController(db, CreatorId,
            $$"""{ "PlayerEventId": {{eventId}}, "RoomInstanceId": {{instance.roomInstanceId}} }""");
        var started = Assert.IsType<OkObjectResult>(await start.BroadcastRoomInstance());
        using (var json = System.Text.Json.JsonDocument.Parse(
            System.Text.Json.JsonSerializer.Serialize(started.Value)))
        {
            Assert.Equal(0, json.RootElement.GetProperty("Result").GetInt32());
            Assert.Equal(instance.roomInstanceId,
                json.RootElement.GetProperty("PlayerEvent").GetProperty("BroadcastingRoomInstanceId").GetInt64());
        }
        Assert.Equal(instance.roomInstanceId,
            (await db.PlayerEvents.SingleAsync(x => x.PlayerEventId == eventId)).BroadcastingRoomInstanceId);

        var stop = CreateController(db, CreatorId,
            $$"""{ "PlayerEventId": {{eventId}}, "RoomInstanceId": null }""");
        var stopped = Assert.IsType<OkObjectResult>(await stop.BroadcastRoomInstance());
        using (var json = System.Text.Json.JsonDocument.Parse(
            System.Text.Json.JsonSerializer.Serialize(stopped.Value)))
        {
            Assert.Equal(System.Text.Json.JsonValueKind.Null,
                json.RootElement.GetProperty("PlayerEvent").GetProperty("BroadcastingRoomInstanceId").ValueKind);
        }
        Assert.Null((await db.PlayerEvents.SingleAsync(x => x.PlayerEventId == eventId)).BroadcastingRoomInstanceId);
    }

    [Fact]
    public async Task BroadcastRoomInstance_NonMultiInstanceEvent_AnswersNotMultiInstance()
    {
        var db = CreateDb();
        var roomId = await SeedRoomAsync(db);
        var eventId = await CreateV2EventAsync(db, roomId);
        var controller = CreateController(db, CreatorId,
            $$"""{ "PlayerEventId": {{eventId}}, "RoomInstanceId": 7 }""");

        var result = Assert.IsType<OkObjectResult>(await controller.BroadcastRoomInstance());

        using var json = System.Text.Json.JsonDocument.Parse(
            System.Text.Json.JsonSerializer.Serialize(result.Value));
        Assert.Equal(27, json.RootElement.GetProperty("Result").GetInt32());
        Assert.Equal(System.Text.Json.JsonValueKind.Null,
            json.RootElement.GetProperty("PlayerEvent").GetProperty("BroadcastingRoomInstanceId").ValueKind);
        Assert.Null((await db.PlayerEvents.SingleAsync(x => x.PlayerEventId == eventId)).BroadcastingRoomInstanceId);
    }

    [Fact]
    public async Task BroadcastRoomInstance_NonCreator_IsForbidden()
    {
        var db = CreateDb();
        var roomId = await SeedRoomAsync(db);
        var eventId = await MakeMultiInstanceAsync(db, await CreateV2EventAsync(db, roomId));
        var stranger = CreateController(db, userId: 99,
            $$"""{ "PlayerEventId": {{eventId}}, "RoomInstanceId": 7 }""");

        Assert.IsType<ForbidResult>(await stranger.BroadcastRoomInstance());
    }

    [Fact]
    public async Task BroadcastRoomInstance_RoundTripsThroughTheReadShapes()
    {
        // Viewers find the broadcast from the event feed, so the persisted instance has to
        // survive into every read, not just the write envelope.
        var db = CreateDb();
        var roomId = await SeedRoomAsync(db);
        var eventId = await MakeMultiInstanceAsync(db, await CreateV2EventAsync(db, roomId));
        db.PlayerEvents.Single(x => x.PlayerEventId == eventId).BroadcastingRoomInstanceId = 1234;
        await db.SaveChangesAsync();

        var feed = await CreateController(db).GetBrowseFeed();
        var feedEvent = Assert.Single(feed, e => e.PlayerEventId == eventId);
        Assert.Equal(1234, feedEvent.BroadcastingRoomInstanceId);

        var byId = await CreateController(db).GetEvent(eventId);
        var ok = Assert.IsType<OkObjectResult>(byId.Result);
        Assert.Equal(1234, Assert.IsType<PlayerEvent>(ok.Value).BroadcastingRoomInstanceId);
    }

    [Fact]
    public async Task DeleteEventResponse_RemovesTheCallersRsvpAndRecomputesAttendees()
    {
        var db = CreateDb();
        var roomId = await SeedRoomAsync(db);
        var creator = CreateController(db, CreatorId);
        var created = await CreateEventAsync(creator, roomId);
        var guest = CreateController(db, userId: 43);
        await guest.SetResponse(created.PlayerEventId, EventResponses.Yes);
        Assert.Equal(2, (await db.PlayerEvents.SingleAsync(x => x.PlayerEventId == created.PlayerEventId)).AttendeeCount);

        var delete = CreateController(db, userId: 43,
            $$"""{ "PlayerEventId": {{created.PlayerEventId}} }""");
        var result = Assert.IsType<OkObjectResult>(await delete.DeleteEventResponse());

        using var json = System.Text.Json.JsonDocument.Parse(
            System.Text.Json.JsonSerializer.Serialize(result.Value));
        Assert.Equal(0, json.RootElement.GetProperty("Result").GetInt32());
        Assert.False(await db.PlayerEventResponses
            .AnyAsync(r => r.PlayerEventId == created.PlayerEventId && r.PlayerId == 43));
        Assert.Equal(1, (await db.PlayerEvents.SingleAsync(x => x.PlayerEventId == created.PlayerEventId)).AttendeeCount);
    }

    [Fact]
    public void BroadcastAndDeleteResponseRoutes_MatchTheClientRouteTable()
    {
        // The 2023 client's route table (global-metadata literals #39422 and #39427) posts to
        // api/playerevents/v1/broadcast and api/playerevents/v1/deleteResponse. Both routes
        // used to 404, which is why event broadcasting never started.
        static IEnumerable<(string Method, string Template)> Routes(string methodName)
            => typeof(EventsAPI).GetMethod(methodName)!
                .GetCustomAttributes(typeof(Microsoft.AspNetCore.Mvc.Routing.HttpMethodAttribute), false)
                .Cast<Microsoft.AspNetCore.Mvc.Routing.HttpMethodAttribute>()
                .SelectMany(a => a.HttpMethods.Select(m => (m, a.Template)));

        Assert.Contains(("POST", "v1/broadcast"), Routes(nameof(EventsAPI.BroadcastRoomInstance)));
        Assert.Contains(("POST", "v1/deleteResponse"), Routes(nameof(EventsAPI.DeleteEventResponse)));
    }
}