RRAC/RecRoomArchive/Controllers/API/Notification/NotificationController.cs

using Microsoft.AspNetCore.Mvc;
using RecRoomArchive.Models.API.Notification;
using System.Net.WebSockets;
using System.Text;
using System.Text.Json;

namespace RecRoomArchive.Controllers.API.Notification
{
    [Route("api/[controller]")]
    [ApiController]
    public class NotificationController : ControllerBase
    {
        private static readonly Dictionary<ulong, WebSocket> Clients = [];

        [HttpGet("v2")]
        public async Task Get()
        {
            if (!HttpContext.WebSockets.IsWebSocketRequest)
            {
                HttpContext.Response.StatusCode = 400;
                return;
            }
            var webSocket = await HttpContext.WebSockets.AcceptWebSocketAsync();
            var buffer = new byte[1024 * 4];
            var result = await webSocket.ReceiveAsync(new ArraySegment<byte>(buffer), CancellationToken.None);
            var handshakeJson = Encoding.UTF8.GetString(buffer, 0, result.Count);
            var handshakeData = JsonSerializer.Deserialize<Dictionary<string, string>>(handshakeJson)!;
            var playerId = ulong.Parse(handshakeData["PlayerId"]);
            Clients[playerId] = webSocket;
            var sessionResponse = JsonSerializer.Serialize(new { SessionId = playerId });
            await webSocket.SendAsync(Encoding.UTF8.GetBytes(sessionResponse), WebSocketMessageType.Text, true, CancellationToken.None);
            await Echo(playerId, webSocket);
            Clients.Remove(playerId);
        }

        private static async Task Echo(ulong playerId, WebSocket webSocket)
        {
            var buffer = new byte[1024 * 4];
            var receiveResult = await webSocket.ReceiveAsync(
                new ArraySegment<byte>(buffer), CancellationToken.None);

            while (!receiveResult.CloseStatus.HasValue)
            {
                var response = JsonSerializer.Serialize(new { SessionId = playerId }); // i think?? only for analytics tho lolololool

                await webSocket.SendAsync(new ArraySegment<byte>(Encoding.UTF8.GetBytes(response)),
                    WebSocketMessageType.Text, true, CancellationToken.None);

                /*await webSocket.SendAsync(
                    new ArraySegment<byte>(buffer, 0, receiveResult.Count),
                    receiveResult.MessageType,
                    receiveResult.EndOfMessage,
                    CancellationToken.None);*/

                receiveResult = await webSocket.ReceiveAsync(
                    new ArraySegment<byte>(buffer), CancellationToken.None);
            }

            await webSocket.CloseAsync(
                receiveResult.CloseStatus.Value,
                receiveResult.CloseStatusDescription,
                CancellationToken.None);

            Clients.Remove(playerId);
        }

        public static async Task Notify(ulong playerId, PushNotificationId id, object msg)
        {
            if (!Clients.TryGetValue(playerId, out var socket))
                return;

            if (socket.State != WebSocketState.Open)
                return;

            var notification = new
            {
                Id = (int)id,
                Msg = msg
            };

            var json = JsonSerializer.Serialize(notification);
            var bytes = Encoding.UTF8.GetBytes(json);

            await socket.SendAsync(bytes, WebSocketMessageType.Text, true, CancellationToken.None);
        }
    }
}