wip new display module

DisplayCommands/Cp437Grid.cs

@@ -0,0 +1,59 @@
+using System.Diagnostics;
+using System.Text;
+
+namespace DisplayCommands;
+
+public sealed class Cp437Grid(ushort width, ushort height)
+{
+    private readonly ByteGrid _byteGrid = new(width, height);
+    
+    public ushort Height { get; } = height;
+    public ushort Width { get; } = width;
+
+    internal Memory<byte> Data => _byteGrid.Data;
+    
+    private readonly Encoding _encoding = Encoding.GetEncoding(437);
+
+    public char this[ushort x, ushort y]
+    {
+        get => ByteToChar(_byteGrid[x, y]);
+        set => _byteGrid[x, y] = CharToByte(value);
+    }
+
+    public string this[ushort row]
+    {
+        get
+        {
+            var rowStart = row * Width;
+            return _encoding.GetString(_byteGrid.Data[rowStart..(rowStart + Width)].Span);
+        }
+        set
+        {
+            ArgumentOutOfRangeException.ThrowIfGreaterThanOrEqual(row, Height, nameof(row));
+            ArgumentOutOfRangeException.ThrowIfGreaterThan(value.Length, Width, nameof(value));
+            ushort x = 0;
+            for (; x < value.Length; x++)
+                _byteGrid[x, row] = CharToByte(value[x]);
+            for (; x < Width; x++)
+                _byteGrid[x, row] = CharToByte(' ');
+        }
+    }
+
+    private byte CharToByte(char c)
+    {
+        ReadOnlySpan<char> valuesStr = stackalloc char[] { c };
+        Span<byte> convertedStr = stackalloc byte[1];
+        var consumed = _encoding.GetBytes(valuesStr, convertedStr);
+        Debug.Assert(consumed == 1);
+        return convertedStr[0];
+        
+    }
+
+    private char ByteToChar(byte b)
+    {
+        ReadOnlySpan<byte> valueBytes = stackalloc byte[] { b };
+        Span<char> resultStr = stackalloc char[1];
+        _encoding.GetChars(valueBytes, resultStr);
+        return resultStr[0];
+    }
+}