wip new display module

DisplayCommands/Internals/DisplayConnection.cs

@@ -0,0 +1,104 @@
+using System.Buffers;
+using System.Diagnostics;
+using System.Net.Sockets;
+using System.Runtime.InteropServices;
+using Microsoft.Extensions.Options;
+
+namespace DisplayCommands.Internals;
+
+internal sealed class DisplayConnection(IOptions<DisplayConfiguration> options) : IDisplayConnection, IDisposable
+{
+    private readonly UdpClient _udpClient = new(options.Value.Hostname, options.Value.Port);
+    private readonly ArrayPool<byte> _arrayPool = ArrayPool<byte>.Shared;
+
+    public ValueTask SendClearAsync()
+    {
+        var header = new HeaderWindow { Command = DisplayCommand.Clear };
+        return SendAsync(header, Memory<byte>.Empty);
+    }
+
+    public ValueTask SendCp437DataAsync(ushort x, ushort y, Cp437Grid grid)
+    {
+        var header = new HeaderWindow
+        {
+            Command = DisplayCommand.Cp437Data,
+            Height = grid.Height,
+            Width = grid.Width,
+            PosX = x,
+            PosY = y
+        };
+        return SendAsync(header, grid.Data);
+    }
+
+    public ValueTask SendCharBrightnessAsync(ushort x, ushort y, ByteGrid luma)
+    {
+        var header = new HeaderWindow
+        {
+            Command = DisplayCommand.CharBrightness,
+            PosX = x,
+            PosY = y,
+            Height = luma.Height,
+            Width = luma.Width
+        };
+
+        return SendAsync(header, luma.Data);
+    }
+
+    public async ValueTask SendBrightnessAsync(byte brightness)
+    {
+        var header = new HeaderWindow { Command = DisplayCommand.Brightness };
+
+        var payloadBuffer = _arrayPool.Rent(1);
+        var payload = payloadBuffer.AsMemory(0, 1);
+        payload.Span[0] = brightness;
+
+        await SendAsync(header, payload);
+        _arrayPool.Return(payloadBuffer);
+    }
+
+    public ValueTask SendHardResetAsync()
+    {
+        var header = new HeaderWindow { Command = DisplayCommand.HardReset };
+        return SendAsync(header, Memory<byte>.Empty);
+    }
+
+    public async ValueTask SendFadeOutAsync(byte loops)
+    {
+        var header = new HeaderWindow { Command = DisplayCommand.FadeOut };
+
+        var payloadBuffer = _arrayPool.Rent(1);
+        var payload = payloadBuffer.AsMemory(0, 1);
+        payload.Span[0] = loops;
+
+        await SendAsync(header, payload);
+        _arrayPool.Return(payloadBuffer);
+    }
+
+    private async ValueTask SendAsync(HeaderWindow header, Memory<byte> payload)
+    {
+        int headerSize;
+        unsafe
+        {
+            // because we specified the struct layout, no platform-specific padding will be added and this is be safe.
+            headerSize = sizeof(HeaderWindow);
+        }
+
+        Debug.Assert(headerSize == 10);
+        var messageSize = headerSize + payload.Length;
+
+        var buffer = _arrayPool.Rent(messageSize);
+        var message = buffer.AsMemory(0, messageSize);
+
+        MemoryMarshal.Write(message.Span, header);
+        payload.CopyTo(message[headerSize..]);
+
+        await _udpClient.SendAsync(message);
+
+        _arrayPool.Return(buffer);
+    }
+
+    public void Dispose()
+    {
+        _udpClient.Dispose();
+    }
+}