send scores to big display

TanksServer/ServicePointDisplay/DisplayBufferView.cs

@@ -0,0 +1,64 @@
+using TanksServer.Models;
+
+namespace TanksServer.ServicePointDisplay;
+
+internal class DisplayBufferView(byte[] data)
+{
+    public byte[] Data => data;
+
+    public ushort Mode
+    {
+        get => GetTwoBytes(0);
+        set => SetTwoBytes(0, value);
+    }
+
+    public ushort TileX
+    {
+        get => GetTwoBytes(2);
+        set => SetTwoBytes(2, value);
+    }
+
+    public ushort TileY
+    {
+        get => GetTwoBytes(4);
+        set => SetTwoBytes(4, value);
+    }
+
+    public ushort WidthInTiles
+    {
+        get => GetTwoBytes(6);
+        set => SetTwoBytes(6, value);
+    }
+
+    public ushort RowCount
+    {
+        get => GetTwoBytes(8);
+        set => SetTwoBytes(8, value);
+    }
+
+    public TilePosition Position
+    {
+        get => new(TileX, TileY);
+        set
+        {
+            ArgumentOutOfRangeException.ThrowIfGreaterThan(value.X, ushort.MaxValue);
+            ArgumentOutOfRangeException.ThrowIfGreaterThan(value.Y, ushort.MaxValue);
+            ArgumentOutOfRangeException.ThrowIfNegative(value.X);
+            ArgumentOutOfRangeException.ThrowIfNegative(value.Y);
+
+            TileX = (ushort)value.X;
+            TileY = (ushort)value.Y;
+        }
+    }
+
+    private ushort GetTwoBytes(int index)
+    {
+        return (ushort)(data[index] * byte.MaxValue + data[index + 1]);
+    }
+
+    private void SetTwoBytes(int index, ushort value)
+    {
+        data[index] = (byte)(value / byte.MaxValue);
+        data[index + 1] = (byte)(value % byte.MaxValue);
+    }
+}

TanksServer/ServicePointDisplay/FixedSizeBitFieldView.cs

@@ -0,0 +1,82 @@
+using System.Collections;
+
+namespace TanksServer.ServicePointDisplay;
+
+internal sealed class FixedSizeBitFieldView(Memory<byte> data) : IList<bool>
+{
+    public int Count => data.Length * 8;
+    public bool IsReadOnly => false;
+
+    IEnumerator IEnumerable.GetEnumerator() => GetEnumerator();
+
+    public IEnumerator<bool> GetEnumerator()
+    {
+        return Enumerable().GetEnumerator();
+
+        IEnumerable<bool> Enumerable()
+        {
+            for (var i = 0; i < Count; i++)
+                yield return this[i];
+        }
+    }
+
+    public void Clear()
+    {
+        var span = data.Span;
+        for (var i = 0; i < data.Length; i++)
+            span[i] = 0;
+    }
+
+    public void CopyTo(bool[] array, int arrayIndex)
+    {
+        for (var i = 0; i < Count && i + arrayIndex < array.Length; i++)
+            array[i + arrayIndex] = this[i];
+    }
+
+    private (int byteIndex, int bitInByteIndex) GetIndexes(int bitIndex)
+    {
+        var byteIndex = bitIndex / 8;
+        var bitInByteIndex = 7 - bitIndex % 8;
+        if (byteIndex >= data.Length)
+        {
+            throw new ArgumentOutOfRangeException(nameof(bitIndex), 
+                $"accessing this bit field at position {bitIndex} would result in an access to byte " +
+                $"{byteIndex} but byte length is {data.Length}");
+        }
+
+        return (byteIndex, bitInByteIndex);
+    }
+
+    public bool this[int bitIndex]
+    {
+        get
+        {
+            var (byteIndex, bitInByteIndex) = GetIndexes(bitIndex);
+            var bitInByteMask = (byte)(1 << bitInByteIndex);
+            return (data.Span[byteIndex] & bitInByteMask) != 0;
+        }
+
+        set
+        {
+            var (byteIndex, bitInByteIndex) = GetIndexes(bitIndex);
+            var bitInByteMask = (byte)(1 << bitInByteIndex);
+
+            if (value)
+            {
+                data.Span[byteIndex] |= bitInByteMask;
+            }
+            else
+            {
+                var withoutBitMask = (byte)(ushort.MaxValue ^ bitInByteMask);
+                data.Span[byteIndex] &= withoutBitMask;
+            }
+        }
+    }
+
+    public void Add(bool item) => throw new NotSupportedException();
+    public bool Contains(bool item) => throw new NotSupportedException();
+    public bool Remove(bool item) => throw new NotSupportedException();
+    public int IndexOf(bool item) => throw new NotSupportedException();
+    public void Insert(int index, bool item) => throw new NotSupportedException();
+    public void RemoveAt(int index) => throw new NotSupportedException();
+}

TanksServer/ServicePointDisplay/FixedSizeCharGridView.cs

@@ -0,0 +1,39 @@
+using System.Text;
+
+namespace TanksServer.ServicePointDisplay;
+
+internal sealed class FixedSizeCharGridView(Memory<byte> data, ushort rowLength, ushort rowCount)
+{
+    public char this[int x, int y]
+    {
+        get => (char)data.Span[x + y * rowLength];
+        set => data.Span[x + y * rowLength] = CharToByte(value);
+    }
+
+    public string this[int row]
+    {
+        get
+        {
+            var rowStart = row * rowLength;
+            return Encoding.UTF8.GetString(data[rowStart..(rowStart + rowLength)].Span);
+        }
+        set
+        {
+            ArgumentOutOfRangeException.ThrowIfGreaterThanOrEqual(row, rowCount, nameof(row));
+            ArgumentOutOfRangeException.ThrowIfGreaterThan(value.Length, rowLength, nameof(value));
+            var x = 0;
+            for (; x < value.Length; x++)
+                this[x, row] = value[x];
+            for (; x < rowLength; x++)
+                this[x, row] = ' ';
+        }
+    }
+
+    private static byte CharToByte(char c)
+    {
+        ArgumentOutOfRangeException.ThrowIfNegative(c);
+        ArgumentOutOfRangeException.ThrowIfGreaterThan(c, (char)byte.MaxValue, nameof(c));
+        // c# strings are UTF-16
+        return (byte)c;
+    }
+}

TanksServer/ServicePointDisplay/PixelDisplayBufferView.cs

@@ -0,0 +1,29 @@
+using TanksServer.Helpers;
+using TanksServer.Services;
+
+namespace TanksServer.ServicePointDisplay;
+
+internal sealed class PixelDisplayBufferView : DisplayBufferView
+{
+    private PixelDisplayBufferView(byte[] data) : base(data)
+    {
+        Pixels = new FixedSizeBitFieldView(Data.AsMemory(10));
+    }
+
+    // ReSharper disable once CollectionNeverQueried.Global (setting values in collection updates underlying byte array)
+    public FixedSizeBitFieldView Pixels { get; }
+
+    public static PixelDisplayBufferView New(ushort x, ushort y, ushort widthInTiles, ushort pixelRows)
+    {
+        // 10 bytes header, one byte per tile row (with one bit each pixel) after that
+        var size = 10 + widthInTiles * pixelRows;
+        return new PixelDisplayBufferView(new byte[size])
+        {
+            Mode = 19,
+            TileX = x,
+            TileY = y,
+            WidthInTiles = widthInTiles,
+            RowCount = pixelRows
+        };
+    }
+}

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();
+    }
+}

TanksServer/ServicePointDisplay/ServicePointDisplayConfiguration.cs

@@ -0,0 +1,8 @@
+namespace TanksServer.ServicePointDisplay;
+
+internal sealed class ServicePointDisplayConfiguration
+{
+    public bool Enable { get; set; } = true;
+    public string Hostname { get; set; } = string.Empty;
+    public int Port { get; set; }
+}

TanksServer/ServicePointDisplay/TextDisplayBuffer.cs

@@ -0,0 +1,18 @@
+using TanksServer.Models;
+
+namespace TanksServer.ServicePointDisplay;
+
+internal sealed class TextDisplayBuffer : DisplayBufferView
+{
+    public TextDisplayBuffer(TilePosition position, ushort charsPerRow, ushort rows)
+        : base(new byte[10 + charsPerRow * rows])
+    {
+        Mode = 3;
+        WidthInTiles = charsPerRow;
+        RowCount = rows;
+        Position = position;
+        Rows = new FixedSizeCharGridView(Data.AsMemory(10), charsPerRow, rows);
+    }
+
+    public FixedSizeCharGridView Rows { get; set; }
+}