Add chess (Oh my gosh big commit)

JoshHeaps.Net/Models/ChessPiece.cs

@@ -0,0 +1,11 @@
+namespace JoshHeaps.Net.Models;
+
+public class ChessPiece(string id, PieceType type, PieceColor color, Position position)
+{
+    public string Id { get; set; } = id;
+    public PieceType Type { get; set; } = type;
+    public PieceColor Color { get; set; } = color;
+    public Position Position { get; set; } = position;
+
+    public bool HasMoved { get; set; } = false;
+}

JoshHeaps.Net/Models/Enums.cs

@@ -0,0 +1,17 @@
+namespace JoshHeaps.Net.Models;
+
+public enum PieceType
+{
+    Pawn,
+    Rook,
+    Knight,
+    Bishop,
+    Queen,
+    King
+}
+
+public enum PieceColor
+{
+    White,
+    Black
+}

JoshHeaps.Net/Models/GameState.cs

@@ -0,0 +1,52 @@
+namespace JoshHeaps.Net.Models;
+
+public class GameState
+{
+    public Guid GameId { get; set; }
+
+    // 8x8 board of references. Null if no piece is present.
+    // row 0 at top -> row 7 at bottom (typical 0-based array).
+    public ChessPiece?[,] Board { get; set; }
+
+    // Whose turn is it?
+    public PieceColor CurrentPlayer { get; set; }
+
+    // To detect if en passant is possible, store the position of a pawn that just moved two squares.
+    // If no pawn is currently "en-passant capturable," this could be null.
+    public Position? EnPassantTarget { get; set; }
+
+    // Castling rights: have the rooks or king moved?
+    // In real chess notation, you track it per side, e.g. "KQkq" style. Let’s store boolean flags:
+    public bool WhiteCanCastleKingside { get; set; }
+    public bool WhiteCanCastleQueenside { get; set; }
+    public bool BlackCanCastleKingside { get; set; }
+    public bool BlackCanCastleQueenside { get; set; }
+
+    // Some game status
+    public bool IsCheck { get; set; }
+    public bool IsCheckmate { get; set; }
+    public bool IsStalemate { get; set; }
+
+    // Keep a history of moves if desired
+    public List<string> MoveHistory { get; set; }
+
+    // A list of all pieces to quickly reference them (optional but convenient).
+    // Alternatively, you can iterate the Board array.
+    public List<ChessPiece> Pieces { get; set; }
+
+    public bool WhiteJoined { get; set; } = false;
+    public bool BlackJoined { get; set; } = false;
+    public Guid WhitePlayerId { get; set; }
+    public Guid BlackPlayerId { get; set; }
+
+    // optional: convenience
+    public bool IsOpen => !WhiteJoined || !BlackJoined;
+
+    public GameState()
+    {
+        GameId = Guid.NewGuid();
+        Board = new ChessPiece[8, 8];
+        Pieces = [];
+        MoveHistory = [];
+    }
+}

JoshHeaps.Net/Models/MoveDto.cs

@@ -0,0 +1,20 @@
+namespace JoshHeaps.Net.Models;
+
+public class MoveDto
+{
+    public Guid GameId { get; set; }
+    public Guid PlayerId { get; set; }
+
+    public string PieceId { get; set; }
+
+    // The square the piece is moving from
+    public int SourceRow { get; set; }
+    public int SourceCol { get; set; }
+
+    // The square the piece is moving to
+    public int TargetRow { get; set; }
+    public int TargetCol { get; set; }
+
+    // If this is a pawn promotion, specify the piece type to promote to; otherwise null
+    public PieceType? PromotionChoice { get; set; }
+}

JoshHeaps.Net/Models/MoveResultDto.cs

@@ -0,0 +1,10 @@
+namespace JoshHeaps.Net.Models;
+
+public class MoveResultDto
+{
+    public bool Success { get; set; }
+    public string Message { get; set; }
+    public bool IsCheck { get; set; }
+    public bool IsCheckmate { get; set; }
+    public bool IsStalemate { get; set; }
+}

JoshHeaps.Net/Models/Position.cs

@@ -0,0 +1,18 @@
+
+namespace JoshHeaps.Net.Models;
+
+public struct Position(int row, int col)
+{
+    public int Row { get; set; } = row;
+    public int Col { get; set; } = col;
+
+    public override readonly string ToString()
+    {
+        return $"[{Row}, {Col}]";
+    }
+
+    internal readonly void Deconstruct(out int row, out int col)
+    {
+        row = Row; col = Col;
+    }
+}