send scores to big display

TanksServer/ServicePointDisplay/SendToServicePointDisplay.cs

@@ -0,0 +1,103 @@
+using System.Diagnostics;
+using System.Net;
+using System.Net.Sockets;
+using Microsoft.Extensions.Logging;
+using TanksServer.Servers;
+using TanksServer.Services;
+using TanksServer.TickSteps;
+
+namespace TanksServer.ServicePointDisplay;
+
+internal sealed class SendToServicePointDisplay : ITickStep, IDisposable
+{
+    private readonly UdpClient? _udpClient;
+    private readonly LastFinishedFrameProvider _lastFinishedFrameProvider;
+    private readonly TextDisplayBuffer _scoresBuffer;
+    private readonly PlayerServer _players;
+    private readonly ILogger<SendToServicePointDisplay> _logger;
+
+    private const int ScoresWidth = 12;
+    private const int ScoresHeight = 20;
+    private const int ScoresPlayerRows = ScoresHeight - 5;
+
+    public SendToServicePointDisplay(
+        IOptions<ServicePointDisplayConfiguration> options,
+        LastFinishedFrameProvider lastFinishedFrameProvider,
+        PlayerServer players,
+        ILogger<SendToServicePointDisplay> logger
+    )
+    {
+        _lastFinishedFrameProvider = lastFinishedFrameProvider;
+        _players = players;
+        _logger = logger;
+        _udpClient = options.Value.Enable
+            ? new UdpClient(options.Value.Hostname, options.Value.Port)
+            : null;
+
+        _scoresBuffer = new(new(MapService.TilesPerRow, 0), 12, 20);
+        _scoresBuffer.Rows[0] = "== TANKS! ==";
+        _scoresBuffer.Rows[1] = "-- scores --";
+
+        _scoresBuffer.Rows[17] = "--  join  --";
+
+        var localIp = GetLocalIp(options.Value.Hostname, options.Value.Port).Split('.');
+        Debug.Assert(localIp.Length == 4); // were talking legacy ip
+        _scoresBuffer.Rows[18] = string.Join('.', localIp[..2]);
+        _scoresBuffer.Rows[19] = string.Join('.', localIp[2..]);
+    }
+
+    private static string GetLocalIp(string host, int port)
+    {
+        using var socket = new Socket(AddressFamily.InterNetwork, SocketType.Dgram, 0);
+        socket.Connect(host, port);
+        var endPoint = socket.LocalEndPoint as IPEndPoint ?? throw new NotSupportedException();
+        return endPoint.Address.ToString();
+    }
+
+    public Task TickAsync()
+    {
+        return _udpClient == null ? Task.CompletedTask : Core();
+
+        async Task Core()
+        {
+            RefreshScores();
+            try
+            {
+                await _udpClient.SendAsync(_scoresBuffer.Data);
+                await _udpClient.SendAsync(_lastFinishedFrameProvider.LastFrame.Data);
+            }
+            catch (SocketException ex)
+            {
+                _logger.LogWarning(ex, "could not send data to service point display");
+            }
+        }
+    }
+
+    private void RefreshScores()
+    {
+        var playersToDisplay = _players.GetAll()
+            .OrderByDescending(p => p.Kills)
+            .Take(ScoresPlayerRows);
+
+        var row = 2;
+        foreach (var p in playersToDisplay)
+        {
+            var score = p.Kills.ToString();
+            var nameLength = ScoresWidth - score.Length;
+
+            var name = p.Name[..nameLength];
+            var spaces = new string(' ', nameLength - name.Length + 1);
+
+            _scoresBuffer.Rows[row] = name + spaces + score;
+            row++;
+        }
+
+        for (; row < 17; row++)
+            _scoresBuffer.Rows[row] = string.Empty;
+    }
+
+    public void Dispose()
+    {
+        _udpClient?.Dispose();
+    }
+}