servicepoint-tanks/tanks-backend/TanksServer/Interactivity/ClientScreenServerConnection.cs
2024-05-06 00:38:18 +02:00

125 lines
3.6 KiB
C#

using System.Buffers;
using System.Diagnostics;
using System.Net.WebSockets;
using DisplayCommands;
using DotNext.Threading;
using TanksServer.Graphics;
namespace TanksServer.Interactivity;
internal sealed class ClientScreenServerConnection
: WebsocketServerConnection, IDisposable
{
private readonly BufferPool _bufferPool;
private readonly PlayerScreenData? _playerDataBuilder;
private readonly Player? _player;
private readonly AsyncAutoResetEvent _nextPackageEvent = new(false, 1);
private int _runningMessageHandlers = 0;
private Package? _next;
public ClientScreenServerConnection(
WebSocket webSocket,
ILogger<ClientScreenServerConnection> logger,
Player? player,
BufferPool bufferPool
) : base(logger, new ByteChannelWebSocket(webSocket, logger, 0))
{
_player = player;
_bufferPool = bufferPool;
_player?.IncrementConnectionCount();
_playerDataBuilder = player == null
? null
: new PlayerScreenData(logger, player);
}
protected override ValueTask HandleMessageAsync(Memory<byte> _)
{
if (Interlocked.Increment(ref _runningMessageHandlers) == 1)
return Core();
Interlocked.Decrement(ref _runningMessageHandlers);
return ValueTask.CompletedTask;
async ValueTask Core()
{
await _nextPackageEvent.WaitAsync();
var package = Interlocked.Exchange(ref _next, null);
if (package == null)
throw new UnreachableException("package should be set here");
await SendAndDisposeAsync(package);
Interlocked.Decrement(ref _runningMessageHandlers);
}
}
public async Task OnGameTickAsync(PixelGrid pixels, GamePixelGrid gamePixelGrid)
{
await Task.Yield();
var next = BuildNextPackage(pixels, gamePixelGrid);
var oldNext = Interlocked.Exchange(ref _next, next);
_nextPackageEvent.Set();
oldNext?.Dispose();
}
public override ValueTask RemovedAsync()
{
_player?.DecrementConnectionCount();
return ValueTask.CompletedTask;
}
public void Dispose()
{
_nextPackageEvent.Dispose();
Interlocked.Exchange(ref _next, null)?.Dispose();
}
private Package BuildNextPackage(PixelGrid pixels, GamePixelGrid gamePixelGrid)
{
var nextPixels = _bufferPool.Rent(pixels.Data.Length);
pixels.Data.CopyTo(nextPixels.Memory);
IMemoryOwner<byte>? nextPlayerData = null;
if (_playerDataBuilder != null)
{
var data = _playerDataBuilder.Build(gamePixelGrid);
nextPlayerData = _bufferPool.Rent(data.Length);
data.CopyTo(nextPlayerData.Memory);
}
var next = new Package(nextPixels, nextPlayerData);
return next;
}
private async ValueTask SendAndDisposeAsync(Package package)
{
try
{
await Socket.SendBinaryAsync(package.Pixels.Memory, package.PlayerData == null);
if (package.PlayerData != null)
await Socket.SendBinaryAsync(package.PlayerData.Memory);
}
catch (WebSocketException ex)
{
Logger.LogWarning(ex, "send failed");
}
finally
{
package.Dispose();
}
}
private sealed record class Package(
IMemoryOwner<byte> Pixels,
IMemoryOwner<byte>? PlayerData
) : IDisposable
{
public void Dispose()
{
Pixels.Dispose();
PlayerData?.Dispose();
}
}
}