@page "/Rooms"
@using LibMatrix.Filters
@using LibMatrix.Helpers
@using LibMatrix.Extensions
@using LibMatrix.Responses
@using System.Collections.ObjectModel
@using System.Diagnostics
@using ArcaneLibs.Extensions
@using MatrixRoomUtils.Abstractions
@inject ILogger<Index> logger
<h3>Room list</h3>

<p>@Status</p>
<p>@Status2</p>

<LinkButton href="/Rooms/Create">Create new room</LinkButton>

<RoomList Rooms="Rooms" GlobalProfile="@GlobalProfile" @bind-StillFetching="RenderContents"></RoomList>

@code {
    private ObservableCollection<RoomInfo> Rooms { get; } = new();
    private UserProfileResponse GlobalProfile { get; set; }

    private AuthenticatedHomeserverGeneric? Homeserver { get; set; }

    private static SyncFilter filter = new() {
        AccountData = new SyncFilter.EventFilter {
            NotTypes = new List<string> { "*" },
            Limit = 1
        },
        Presence = new SyncFilter.EventFilter {
            NotTypes = new List<string> { "*" },
            Limit = 1
        },
        Room = new SyncFilter.RoomFilter {
            AccountData = new SyncFilter.RoomFilter.StateFilter {
                NotTypes = new List<string> { "*" },
                Limit = 1
            },
            Ephemeral = new SyncFilter.RoomFilter.StateFilter {
                NotTypes = new List<string> { "*" },
                Limit = 1
            },
            State = new SyncFilter.RoomFilter.StateFilter {
                Types = new List<string> {
                    "m.room.create",
                    "m.room.name",
                    "m.room.avatar",
                    "org.matrix.mjolnir.shortcode",
                    "m.room.power_levels",
                }
            },
            Timeline = new SyncFilter.RoomFilter.StateFilter {
                NotTypes = new List<string> { "*" },
                Limit = 1
            }
        }
    };

    // private static SyncFilter profileUpdateFilter = new() {
    //     AccountData = new SyncFilter.EventFilter {
    //         NotTypes = new List<string> { "*" },
    //         Limit = 1
    //     },
    //     Presence = new SyncFilter.EventFilter {
    //         NotTypes = new List<string> { "*" },
    //         Limit = 1
    //     },
    //     Room = new SyncFilter.RoomFilter {
    //         AccountData = new SyncFilter.RoomFilter.StateFilter {
    //             NotTypes = new List<string> { "*" },
    //             Limit = 1
    //         },
    //         Ephemeral = new SyncFilter.RoomFilter.StateFilter {
    //             NotTypes = new List<string> { "*" },
    //             Limit = 1
    //         },
    //         State = new SyncFilter.RoomFilter.StateFilter {
    //             Types = new List<string> {
    //                 "m.room.member"
    //             },
    //             Senders = new()
    //         },
    //         Timeline = new SyncFilter.RoomFilter.StateFilter {
    //             NotTypes = new List<string> { "*" },
    //             Limit = 1
    //         }
    //     }
    // };

    private SyncHelper syncHelper;

    // SyncHelper profileSyncHelper;

    protected override async Task OnInitializedAsync() {
        Homeserver = await MRUStorage.GetCurrentSessionOrNavigate();
        if (Homeserver is null) return;
        var rooms = await Homeserver.GetJoinedRooms();
        // SemaphoreSlim _semaphore = new(160, 160);

        var roomTasks = rooms.Select(async room => {
            RoomInfo ri;
            // await _semaphore.WaitAsync();
            ri = new() { Room = room };
            await Task.WhenAll((filter.Room?.State?.Types ?? []).Select(x => ri.GetStateEvent(x)));
            return ri;
        }).ToAsyncEnumerable();

        await foreach (var room in roomTasks) {
            Rooms.Add(room);
            StateHasChanged();
            // await Task.Delay(50);
            // _semaphore.Release();
        }

        if (rooms.Count >= 150) RenderContents = true;

        GlobalProfile = await Homeserver.GetProfileAsync(Homeserver.WhoAmI.UserId);
        syncHelper = new SyncHelper(Homeserver, logger) {
            Timeout = 30000,
            Filter = filter,
            MinimumDelay = TimeSpan.FromMilliseconds(5000)
        };
        //  profileSyncHelper = new SyncHelper(Homeserver, logger) {
        //     Timeout = 10000,
        //     Filter = profileUpdateFilter,
        //     MinimumDelay = TimeSpan.FromMilliseconds(5000)
        //  };
        // profileUpdateFilter.Room.State.Senders.Add(Homeserver.WhoAmI.UserId);

        RunSyncLoop(syncHelper);
        // RunSyncLoop(profileSyncHelper);
        RunQueueProcessor();

        await base.OnInitializedAsync();
    }

    private async Task RunQueueProcessor() {
        var renderTimeSw = Stopwatch.StartNew();
        var isInitialSync = true;
        while (true) {
            try {
                while (queue.Count == 0) {
                    Console.WriteLine("Queue is empty, waiting...");
                    await Task.Delay(isInitialSync ? 100 : 2500);
                }

                Console.WriteLine($"Queue no longer empty after {renderTimeSw.Elapsed}!");

                int maxUpdates = 10;
                isInitialSync = false;
                while (maxUpdates-- > 0 && queue.TryDequeue(out var queueEntry)) {
                    var (roomId, roomData) = queueEntry;
                    Console.WriteLine($"Dequeued room {roomId}");
                    RoomInfo room;

                    if (Rooms.Any(x => x.Room.RoomId == roomId)) {
                        room = Rooms.First(x => x.Room.RoomId == roomId);
                        Console.WriteLine($"QueueWorker: {roomId} already known with {room.StateEvents?.Count ?? 0} state events");
                    }
                    else {
                        Console.WriteLine($"QueueWorker: encountered new room {roomId}!");
                        room = new RoomInfo() {
                            Room = Homeserver.GetRoom(roomId)
                        };
                        Rooms.Add(room);
                    }

                    if (room.StateEvents is null) {
                        Console.WriteLine($"QueueWorker: {roomId} does not have state events on record?");
                        throw new InvalidDataException("Somehow this is null???");
                    }

                    if (roomData.State?.Events is { Count: > 0 })
                        room.StateEvents.MergeStateEventLists(roomData.State.Events);
                    else {
                        Console.WriteLine($"QueueWorker: could not merge state for {room.Room.RoomId} as new data contains no state events!");
                    }
                }
                Console.WriteLine($"QueueWorker: {queue.Count} entries left in queue, {maxUpdates} maxUpdates left, RenderContents: {RenderContents}");
                    Status = $"Got {Rooms.Count} rooms so far! {queue.Count} entries in processing queue...";

                RenderContents |= queue.Count == 0;
                await Task.Delay(Rooms.Count);
            }
            catch (Exception e) {
                Console.WriteLine("QueueWorker exception: " + e);
            }
        }
    }

    private bool RenderContents { get; set; } = false;

    private string _status;

    public string Status {
        get => _status;
        set {
            _status = value;
            StateHasChanged();
        }
    }

    private string _status2;

    public string Status2 {
        get => _status2;
        set {
            _status2 = value;
            StateHasChanged();
        }
    }

    private Queue<KeyValuePair<string, SyncResponse.RoomsDataStructure.JoinedRoomDataStructure>> queue = new();

    private async Task RunSyncLoop(SyncHelper syncHelper) {
        Status = "Initial syncing...";
        Console.WriteLine("starting sync");

        var syncs = syncHelper.EnumerateSyncAsync();
        await foreach (var sync in syncs) {
            Console.WriteLine("trying sync");
            if (sync is null) continue;

            Status = $"Got sync with {sync.Rooms?.Join?.Count ?? 0} room updates, next batch: {sync.NextBatch}!";
            if (sync?.Rooms?.Join != null)
                foreach (var joinedRoom in sync.Rooms.Join)
                    if ( /*joinedRoom.Value.AccountData?.Events?.Count > 0 ||*/ joinedRoom.Value.State?.Events?.Count > 0) {
                        joinedRoom.Value.State.Events.RemoveAll(x => x.Type == "m.room.member" && x.StateKey != Homeserver.WhoAmI?.UserId);
                        // We can't trust servers to give us what we ask for, and this ruins performance
                        // Thanks, Conduit.
                        joinedRoom.Value.State.Events.RemoveAll(x => filter.Room?.State?.Types?.Contains(x.Type) == false);
                        if (filter.Room?.State?.NotSenders?.Any() ?? false)
                            joinedRoom.Value.State.Events.RemoveAll(x => filter.Room?.State?.NotSenders?.Contains(x.Sender) ?? false);

                        queue.Enqueue(joinedRoom);
                    }
            if (sync.Rooms.Leave is {Count: > 0})
                foreach (var leftRoom in sync.Rooms.Leave)
                    if (Rooms.Any(x => x.Room.RoomId == leftRoom.Key))
                        Rooms.Remove(Rooms.First(x => x.Room.RoomId == leftRoom.Key));

            Status = $"Got {Rooms.Count} rooms so far! {queue.Count} entries in processing queue... " +
                     $"{sync?.Rooms?.Join?.Count ?? 0} new updates!";

            Status2 = $"Next batch: {sync.NextBatch}";
        }
    }

}