Convert Hexapawn to common library

46_Hexapawn/csharp/IReadWriteExtensions.cs

@@ -0,0 +1,42 @@
+using System;
+using System.Linq;
+using Games.Common.IO;
+
+namespace Hexapawn;
+
+// Provides input methods which emulate the BASIC interpreter's keyboard input routines
+internal static class IReadWriteExtensions
+{
+    internal static char GetYesNo(this IReadWrite io, string prompt)
+    {
+        while (true)
+        {
+            var response = io.ReadString($"{prompt} (Y-N)").FirstOrDefault();
+            if ("YyNn".Contains(response))
+            {
+                return char.ToUpperInvariant(response);
+            }
+        }
+    }
+
+    // Implements original code:
+    //   120 PRINT "YOUR MOVE";
+    //   121 INPUT M1,M2
+    //   122 IF M1=INT(M1)AND M2=INT(M2)AND M1>0 AND M1<10 AND M2>0 AND M2<10 THEN 130
+    //   123 PRINT "ILLEGAL CO-ORDINATES."
+    //   124 GOTO 120
+    internal static Move ReadMove(this IReadWrite io, string prompt)
+    {
+        while(true)
+        {
+            var (from, to) = io.Read2Numbers(prompt);
+
+            if (Move.TryCreate(from, to, out var move))
+            {
+                return move;
+            }
+
+            io.WriteLine("Illegal Coordinates.");
+        }
+    }
+}