cpp board can go back and forth from FEN

folder

cpp/board.cpp

@@ -0,0 +1,110 @@
+#include <cctype>
+#include <ios>
+#include <iostream>
+#include <map>
+#include <string>
+
+enum Piece {
+    None = 0,
+    King = 1,
+    Pawn = 2,
+    Knigt = 3,
+    Bishop = 4,
+    Rook = 5,
+    Queen = 6,
+};
+
+enum Colour {
+    White = 8,
+    Black = 16,
+};
+
+enum CastleRights {
+    KingSide = 1,
+    QueenSide = 2,
+};
+
+class Board {
+  public: // make this private after debugging
+    int squares[64] = {Piece::None};
+    Colour turn;
+    int castle_rights;
+
+  public:
+    static Board* setup_fen_position(std::string fen);
+
+    std::string to_fen();
+};
+
+Board* Board::setup_fen_position(std::string fen) {
+    Board* board = new Board();
+    std::map<char, Piece> c2p{
+        {'k', Piece::King},
+        {'p', Piece::Pawn},
+        {'n', Piece::Knigt},
+        {'b', Piece::Bishop},
+        {'r', Piece::Rook},
+        {'q', Piece::Queen},
+    };
+
+    std::string fen_board = fen.substr(0, fen.find(' '));
+    int rank = 7, file = 0;
+    for (char symbol : fen_board) {
+        if (symbol == '/') {
+            file = 0;
+            rank--;
+            continue;
+        }
+
+        if (std::isdigit(symbol))
+            file += symbol - '0';
+        else {
+            Colour colour =
+                std::isupper(symbol) ? Colour::White : Colour::Black;
+
+            Piece piece = c2p[std::tolower(symbol)];
+            board->squares[rank * 8 + file] = colour | piece;
+            file++;
+        }
+    }
+    return board;
+}
+
+std::string Board::to_fen() {
+    std::map<int, char> p2c{
+        {Piece::King, 'k'},
+        {Piece::Pawn, 'p'},
+        {Piece::Knigt, 'n'},
+        {Piece::Bishop, 'b'},
+        {Piece::Rook, 'r'},
+        {Piece::Queen, 'q'},
+    };
+
+    std::string ret;
+    for (int rank = 7; rank >= 0; rank--) {
+        int empty_cell_counter = 0;
+        for (int file = 0; file < 8; file++) {
+            if (this->squares[rank * 8 + file] == Piece::None) {
+                empty_cell_counter++;
+                continue;
+            }
+
+            int full_piece = this->squares[rank * 8 + file];
+            char piece = p2c[full_piece & 0b111];
+            Colour colour = (full_piece & 0b11000) == Colour::White
+                              ? Colour::White
+                              : Colour::Black;
+
+            if (empty_cell_counter > 0) {
+                ret += std::to_string(empty_cell_counter);
+                empty_cell_counter = 0;
+            }
+            ret += colour == Colour::White ? std::toupper(piece) : piece;
+        }
+        if (empty_cell_counter > 0)
+            ret += std::to_string(empty_cell_counter);
+        if (rank > 0)
+            ret += "/";
+    }
+    return ret;
+}

cpp/main.cpp

@@ -0,0 +1,16 @@
+#include "board.cpp"
+
+int main(int argc, char* argv[]) {
+    std::string pos =
+        "rnbq1k1r/pp1Pbppp/2p5/8/2B5/8/PPP1NnPP/RNBQK2R w KQ - 1 8";
+    Board* b = Board::setup_fen_position(pos);
+
+    std::string fen = b->to_fen();
+
+    std::cout << pos << std::endl;
+    std::cout << fen << std::endl;
+
+    std::cout << (fen.substr(0, fen.find(" ")) == pos.substr(0, pos.find(" ")))
+              << std::endl;
+    return 0;
+}

cpp/tests/fen.cpp

@@ -0,0 +1,37 @@
+#include "../board.cpp"
+
+#define IS_TRUE(x)                                                             \
+    {                                                                          \
+        if (!(x))                                                              \
+            std::cout << __FUNCTION__ << " failed on line " << __LINE__        \
+                      << std::endl;                                            \
+    }
+
+#define ASSERT_EQUALS(expected, actual)                                        \
+    {                                                                          \
+        if (expected != actual)                                                \
+            std::cout << "Expected: " << std::endl                             \
+                      << '\t' << expected << std::endl                         \
+                      << "Got: " << std::endl                                  \
+                      << '\t' << actual << std::endl;                          \
+    }
+
+int main() {
+    std::string pos = "rnbqkbnr/pppppppp/8/8/8/8/PPPPPPPP/RNBQKBNR";
+    ASSERT_EQUALS(pos, Board::setup_fen_position(pos)->to_fen());
+
+    pos = "r1bk3r/p2pBpNp/n4n2/1p1NP2P/6P1/3P4/P1P1K3/q5b1";
+    ASSERT_EQUALS(pos, Board::setup_fen_position(pos)->to_fen());
+
+    pos = "rnbqkbnr/pppppppp/8/8/4P3/8/PPPP1PPP/RNBQKBNR";
+    ASSERT_EQUALS(pos, Board::setup_fen_position(pos)->to_fen());
+
+    pos = "4k2r/6r1/8/8/8/8/3R4/R3K3";
+    ASSERT_EQUALS(pos, Board::setup_fen_position(pos)->to_fen());
+
+    pos = "8/8/8/4p1K1/2k1P3/8/8/8";
+    ASSERT_EQUALS(pos, Board::setup_fen_position(pos)->to_fen());
+
+    pos = "8/5k2/3p4/1p1Pp2p/pP2Pp1P/P4P1K/8/8";
+    ASSERT_EQUALS(pos, Board::setup_fen_position(pos)->to_fen());
+}

python/src/ai/ai.py

@@ -0,0 +1,169 @@
+from collections import defaultdict
+import time
+
+from tqdm import tqdm
+from logic.board import INITIAL_BOARD, Board
+from logic.move import Move
+from logic.pieces.piece import Colour
+
+pos2expected = {
+    # -- Position 1
+    "rnbqkbnr/pppppppp/8/8/8/8/PPPPPPPP/RNBQKBNR w KQkq - 0 1": {
+        1: 20,
+        2: 400,
+        3: 8_902,
+        4: 197_281,
+    },
+
+    # -- Position 2
+    "r3k2r/p1ppqpb1/bn2pnp1/3PN3/1p2P3/2N2Q1p/PPPBBPPP/R3K2R w KQkq - 0 1": {
+        1: 48,
+        2: 2_039,
+        3: 97_862,
+        4: 4_085_603,
+    },
+
+    # -- Position 3
+    "8/2p5/3p4/KP5r/1R3p1k/8/4P1P1/8 w - - 0 1": {
+        1: 14,
+        2: 191,
+        3: 2_812,
+        4: 43_238,
+        5: 674_624,
+    },
+
+    # -- Position 4
+    "r3k2r/Pppp1ppp/1b3nbN/nP6/BBP1P3/q4N2/Pp1P2PP/R2Q1RK1 w kq - 0 1": {
+        1: 6,
+        2: 264,
+        3: 9467,
+        4: 422_333,
+    },
+
+    # -- Position 5
+    "rnbq1k1r/pp1Pbppp/2p5/8/2B5/8/PPP1NnPP/RNBQK2R w KQ - 1 8": {
+        1: 44,
+        2: 1486,
+        3: 62379,
+        4: 2103487,
+    },
+
+    # -- Position 6
+    "r4rk1/1pp1qppp/p1np1n2/2b1p1B1/2B1P1b1/P1NP1N2/1PP1QPPP/R4RK1 w - - 0 10": {
+        1: 46,
+        2: 2079,
+        3: 89890,
+        4: 3894594,
+    },
+}
+
+tick = "\033[92m✔️\033[0m"  # Green Tick
+cross = "\033[91m❌\033[0m"  # Red Cross
+
+res = defaultdict(lambda : 0)
+
+def peft(pos: str):
+    global res
+    expected = pos2expected[pos]
+    board = Board.setup_FEN_position(pos)
+    for depth in expected:
+        with tqdm(total=expected[depth], desc=f"Depth: {depth}") as bar:
+            start = time.process_time()
+            moves = move_generation_test(bar, board, depth, depth)
+            bar.close()
+            elapsed = time.process_time() - start
+            elapsed *= 1_000
+
+            print("Depth:", depth, end=" ")
+            print("Result:", moves, end=" ")
+            if moves == expected[depth]:
+                print(f"{tick}", end=" ")
+            else:
+                print(f"{cross} (expected {expected[depth]})", end=" ")
+            print("positions Time:", int(elapsed), "milliseconds")
+
+            if moves != expected[depth]:
+                print()
+                for key, value in res.items():
+                    print(f"{key}: {value}")
+
+
+
+def move_generation_test(bar, board: Board, depth: int, max_depth, first = None):
+    global res
+    if first is None:
+        res = defaultdict(lambda : 0)
+
+    if board.is_terminal():
+        # bar.update(1)
+        # res[first] += 1
+        return 0
+
+    if depth == 0:
+        res[first] += 1
+        bar.update(1)
+        return 1
+
+    moves = board.legal_moves()
+    if depth == 1:
+        res[first] += len(moves)
+        bar.update(len(moves))
+        return len(moves)
+
+    num_pos = 0
+    for move in moves:
+        tmp_board = board.make_move(move)
+        if first is None:
+            first = move.piece.pos.to_algebraic() + move.pos.to_algebraic()
+
+        if first == "f7h8":
+            print(tmp_board.legal_moves())
+        num_pos += move_generation_test(bar, tmp_board, depth - 1, max_depth, first = first)
+
+        if depth == max_depth:
+            first = None
+
+    return num_pos
+
+
+
+def play_game(board: Board, strategies: dict, verbose: bool = False) -> Board:
+    """Play a turn-taking game. `strategies` is a {player_name: function} dict,
+    where function(state) is used to get the player's move."""
+    state = board
+    move_counter = 1
+    while not (board.is_checkmate_for(board._turn) or board.is_stalemate_for(board._turn)):
+        player = board._turn
+        move = strategies[player](state)
+        state = board.make_move(move)
+        if verbose:
+            if player == Colour.WHITE:
+                print(str(move_counter) + ".", move, end=" ")
+            else:
+                print(move)
+
+    return state
+
+def minmax_search(state: Board) -> tuple[float, Move]:
+    """Search game tree to determine best move; return (value, move) pair."""
+    return _max_value(state) if state._turn == Colour.WHITE else _min_value(state)
+
+def _max_value(state: Board) -> tuple[float, Move]:
+    if state.is_terminal():
+        return state.utility(), None
+    v, move = -float("inf"), None
+    for a in state.legal_moves():
+        v2, _ = _min_value(state.make_move(a))
+        if v2 > v:
+            v, move = v2, a
+    return v, move
+
+def _min_value(state: Board) -> tuple[float, Move]:
+    if state.is_terminal():
+        return state.utility(), None
+    v, move = float("inf"), None
+    for a in state.legal_moves():
+        v2, _ = _min_value(state.make_move(a))
+        if v2 < v:
+            v, move = v2, a
+    return v, move

python/src/logic/board.py

@@ -15,9 +15,11 @@ class Board:
         self._white: dict[Position, Piece] = {}
         self._black: dict[Position, Piece] = {}
         self._turn = None
-        self._white_castling_write = set()
+        self._white_castling_rights = set()
-        self._black_castling_write = set()
+        self._black_castling_rights = set()
         self._en_passant_target = None
+        self._n_moves = 0
+        self._n_half_moves = 0
 
     @staticmethod
     def _piece_class_from_char(c: str) -> Type[Piece]:
@@ -83,22 +85,41 @@ class Board:
         for c in position[index:]:
             index += 1
             if c == "-" or c == " ":
+                if c == "-":
+                    index += 1
                 break
 
             sides = "kq"
             assert c in sides or c in sides.upper(), f"The FEN position is malformed, the castling rights should be either k or q (both either lower- or upper-case), instead is '{c}'"
             if c == "K":
-                ret._white_castling_write.add(CastleSide.King)
+                ret._white_castling_rights.add(CastleSide.King)
             if c == "Q":
-                ret._white_castling_write.add(CastleSide.Queen)
+                ret._white_castling_rights.add(CastleSide.Queen)
             if c == "k":
-                ret._black_castling_write.add(CastleSide.King)
+                ret._black_castling_rights.add(CastleSide.King)
             if c == "q":
-                ret._black_castling_write.add(CastleSide.Queen)
+                ret._black_castling_rights.add(CastleSide.Queen)
 
         # -- En passant target
         if position[index] != "-":
-            ret._en_passant_target = position[index:index+2]
+            pos = Position.from_algebraic(position[index:index+2]) 
+            index += 2
+            if pos.y == 2:
+                pos.y += 1
+                assert pos in ret._white, "En passant target is not in the position"
+                ret._en_passant_target = ret._white[pos]
+            elif pos.y == 5:
+                pos.y -= 1
+                assert pos in ret._black, "En passant target is not in the position"
+                ret._en_passant_target = ret._black[pos]
+            else:
+                raise ValueError("You can't have a en passant target that is not on the third or sixth rank")
+        else:
+            index += 1
+        index += 1
+
+        ret._n_half_moves = int(position[index:position.find(" ", index + 1)])
+        ret._n_moves = int(position[position.find(" ", index)+1:])
 
         return ret
 
@@ -152,8 +173,8 @@ class Board:
                 return False
         return True
 
-    def castling_writes_for(self, colour: Colour) -> set[CastleSide]:
+    def castling_rights_for(self, colour: Colour) -> set[CastleSide]:
-        return self._white_castling_write if colour == Colour.WHITE else self._black_castling_write
+        return self._white_castling_rights if colour == Colour.WHITE else self._black_castling_rights
 
     def make_move(self, move: Move) -> "Board":
         dest_piece = self.piece_at(move.pos.x, move.pos.y) 
@@ -161,15 +182,18 @@ class Board:
         if dest_piece:
             assert dest_piece.colour != move.piece.colour, "A piece cannot cannot eat another piece of the same colour"
 
+        # -- Copy current state
         ret = Board()
         ret._white = self._white.copy()
         ret._black = self._black.copy()
         ret._turn = Colour.WHITE if self._turn == Colour.BLACK else Colour.BLACK
-        ret._white_castling_write = self._white_castling_write.copy()
+        ret._white_castling_rights = self._white_castling_rights.copy()
-        ret._black_castling_write = self._black_castling_write.copy()
+        ret._black_castling_rights = self._black_castling_rights.copy()
-        ret._en_passant_target = self._en_passant_target
+
 
         piece = move.piece
+
+        # -- Actually make the move
         pieces_moving, other_pieces = (ret._white, ret._black) if piece.colour == Colour.WHITE else (ret._black, ret._white)
 
         del pieces_moving[piece.pos]
@@ -177,6 +201,29 @@ class Board:
         if move.pos in other_pieces:
             del other_pieces[move.pos]
 
+        if piece.colour == Colour.BLACK:
+            ret._n_moves = self._n_moves + 1
+
+        if move.is_capturing or type(piece) == Pawn:
+            ret._n_half_moves = 0
+        else:
+            ret._n_half_moves = self._n_half_moves + 1
+
+        if move.en_passant:
+            pos_to_remove = Position(move.pos.x, move.pos.y + (1 if self._turn == Colour.BLACK else -1))
+            del other_pieces[pos_to_remove]
+
+        if move.promotes_to is not None:
+            assert type(piece) == Pawn, "Trying to promote something that is not a pawn: not good!"
+            pieces_moving[move.pos] = move.promotes_to(move.pos, piece.colour)
+
+        # -- Set en passant target if needed
+        if move.becomes_en_passant_target:
+            ret._en_passant_target = pieces_moving[move.pos]
+        else:
+            ret._en_passant_target = None
+
+        # -- Handle castling (just move the rook over)
         if move.castle_side == CastleSide.King:
             rook_pos = Position(7, piece.pos.y)
             assert rook_pos in pieces_moving and type(pieces_moving[rook_pos]) == Rook, "Either rook is absent from the king side or you are trying to castle with something else than a rook..."
@@ -191,24 +238,123 @@ class Board:
             new_rook_pos = Position(3, piece.pos.y)
             pieces_moving[new_rook_pos] = Rook(new_rook_pos, piece.colour)
 
+        # -- Check for castling rights
         if piece.colour == Colour.WHITE:
             if type(piece) == King:
-                ret._white_castling_write = set()
+                ret._white_castling_rights = set()
 
             if type(piece) == Rook:
-                if piece.pos.x == 0 and CastleSide.Queen in ret._white_castling_write:
+                if piece.pos.x == 0 and CastleSide.Queen in ret._white_castling_rights:
-                    ret._white_castling_write.remove(CastleSide.Queen)
+                    ret._white_castling_rights.remove(CastleSide.Queen)
-                elif piece.pos.x == 7 and CastleSide.King in ret._white_castling_write:
+                elif piece.pos.x == 7 and CastleSide.King in ret._white_castling_rights:
-                    ret._white_castling_write.remove(CastleSide.King)
+                    ret._white_castling_rights.remove(CastleSide.King)
+
+            if move.is_capturing and move.pos.y == 7 and move.pos in self._black and type(self._black[move.pos]) == Rook:
+                if move.pos.x == 0 and CastleSide.Queen in ret._black_castling_rights:
+                    ret._black_castling_rights.remove(CastleSide.Queen)
+                elif move.pos.x == 7 and CastleSide.King in ret._black_castling_rights:
+                    ret._black_castling_rights.remove(CastleSide.King)
         else:
             if type(piece) == King:
-                ret._black_castling_write = set()
+                ret._black_castling_rights = set()
 
             if type(piece) == Rook:
-                if piece.pos.x == 0 and CastleSide.Queen in ret._black_castling_write:
+                if piece.pos.x == 0 and CastleSide.Queen in ret._black_castling_rights:
-                    ret._black_castling_write.remove(CastleSide.Queen)
+                    ret._black_castling_rights.remove(CastleSide.Queen)
-                elif piece.pos.x == 7 and CastleSide.King in ret._black_castling_write:
+                elif piece.pos.x == 7 and CastleSide.King in ret._black_castling_rights:
-                    ret._black_castling_write.remove(CastleSide.King)
+                    ret._black_castling_rights.remove(CastleSide.King)
 
+            if move.is_capturing and move.pos.y == 0 and move.pos in self._white and type(self._white[move.pos]) == Rook:
+                if move.pos.x == 0 and CastleSide.Queen in ret._white_castling_rights:
+                    ret._white_castling_rights.remove(CastleSide.Queen)
+                elif move.pos.x == 7 and CastleSide.King in ret._white_castling_rights:
+                    ret._white_castling_rights.remove(CastleSide.King)
 
         return ret
+
+    def to_fen_string(self):
+        ret = ""
+        for y in range(7, -1, -1):
+            empty_cell_counter = 0
+            for x in range(8):
+                pos = Position(x, y)
+
+                piece = None
+                if pos in self._white:
+                    piece = self._white[pos]
+                elif pos in self._black:
+                    piece = self._black[pos]
+
+                if piece is None:
+                    empty_cell_counter += 1
+                    continue
+
+                if empty_cell_counter > 0:
+                    ret += str(empty_cell_counter)
+                    empty_cell_counter = 0
+                letter = piece.letter()
+                ret += letter.lower() if piece.colour == Colour.BLACK else letter.upper()
+
+            if empty_cell_counter > 0:
+                ret += str(empty_cell_counter)
+
+            if y > 0:
+                ret += "/"
+        ret += " "
+
+        ret += "w" if self._turn == Colour.WHITE else "b"
+        ret += " "
+
+        if len(self._white_castling_rights) == 0 and len(self._black_castling_rights) == 0:
+            ret += "-"
+        else: 
+            if CastleSide.King in self._white_castling_rights:
+                ret += "K"
+            if CastleSide.Queen in self._white_castling_rights:
+                ret += "Q"
+
+            if CastleSide.King in self._black_castling_rights:
+                ret += "k"
+            if CastleSide.Queen in self._black_castling_rights:
+                ret += "q"
+        ret += " "
+
+        if self._en_passant_target is not None:
+            pos = Position(self._en_passant_target.pos.x, self._en_passant_target.pos.y)
+            pos.y += -1 if self._en_passant_target.colour == Colour.WHITE else 1
+            ret += pos.to_algebraic()
+        else:
+            ret += "-"
+        ret += " "
+
+        ret += str(self._n_half_moves)
+        ret += " "
+        ret += str(self._n_moves)
+
+        return ret
+
+
+    def legal_moves(self) -> list[Move]:
+        ret = []
+        pieces = self._white if self._turn == Colour.WHITE else self._black
+        for piece in pieces.values():
+            ret += piece.legal_moves(self)
+        return ret
+
+    def is_terminal(self) -> bool:
+        return self.is_stalemate_for(Colour.WHITE) or self.is_stalemate_for(Colour.BLACK) or self.is_checkmate_for(Colour.WHITE) or self.is_checkmate_for(Colour.BLACK)
+
+    def utility(self) -> int:
+        if self.is_stalemate_for(Colour.WHITE) or self.is_stalemate_for(Colour.BLACK):
+            return 0
+
+        if self.is_checkmate_for(Colour.WHITE):
+            return 1
+
+        if self.is_checkmate_for(Colour.BLACK):
+            return -1
+        
+        raise ValueError("Cannot determine the utility of board become it neither checkmate nor stalemate for either players")
+
+_fen_pos = "rnbqkbnr/pppppppp/8/8/8/8/PPPPPPPP/RNBQKBNR w KQkq - 0 1"
+INITIAL_BOARD = Board.setup_FEN_position(_fen_pos)

python/src/logic/move.py

@@ -1,4 +1,5 @@
 # from logic.pieces.piece import Piece
+from typing import Type
 from logic.position import Position
 from enum import Enum
 
@@ -8,11 +9,14 @@ class CastleSide(Enum):
     Queen = "O-O-O"
 
 class Move:
-    def __init__(self, piece: "Piece", pos: Position,/, is_capturing: bool = False, castle_side: CastleSide = CastleSide.Neither) -> None:
+    def __init__(self, piece: "Piece", pos: Position,/, is_capturing: bool = False, castle_side: CastleSide = CastleSide.Neither, en_passant: bool = False, becomes_en_passant_target: bool = False, promotes_to: Type["Piece"] = None) -> None:
         self.piece = piece
         self.pos = pos
         self.is_capturing = is_capturing
         self.castle_side = castle_side
+        self.becomes_en_passant_target = becomes_en_passant_target
+        self.en_passant = en_passant
+        self.promotes_to = promotes_to
 
     def to_algebraic(self) -> str:
         raise NotImplementedError("The move can't be translated to algbraic notation, as it was not implemented")
@@ -28,10 +32,19 @@ class Move:
             return "O-O-O"
 
         ret = ""
-        if type(self.piece).__name__ != "Pawn":
+        if type(self.piece).__name__ == "Pawn":
+            if self.is_capturing:
+                ret += self.piece.pos.to_algebraic()[0]
+                ret += "x"
+                ret += self.pos.to_algebraic()
+            else:
+                ret += self.pos.to_algebraic()
+        else:
             ret += self.piece.letter().upper()
+            if self.is_capturing:
+                ret += "x"
+            ret += str(self.pos)
         
-        ret += str(self.pos)
         return ret
     
     def __repr__(self) -> str:

python/src/logic/pieces/bishop.py

@@ -17,7 +17,7 @@ class Bishop(Piece):
         # looking north west
         ret.extend(self._look_direction(board, -1, 1))
 
-        if not looking_for_check and board.is_check_for(self.colour):
+        if not looking_for_check:# and board.is_check_for(self.colour):
             return self.keep_only_blocking(ret, board)
 
         return ret

python/src/logic/pieces/king.py

@@ -23,11 +23,11 @@ class King(Piece):
             return self.keep_only_blocking(ret, board)
 
         # -- Castles
-        castling_writes = board.castling_writes_for(self.colour)
+        castling_rights = board.castling_rights_for(self.colour)
-        if len(castling_writes) == 0:
+        if len(castling_rights) == 0:
             return ret
 
-        if CastleSide.King in castling_writes:
+        if CastleSide.King in castling_rights:
             clear = True
             for dx in range(1, 3):
                 x = self.pos.x + dx
@@ -45,9 +45,9 @@ class King(Piece):
             if clear:
                 ret.append(Move(self, Position(6, self.pos.y), castle_side=CastleSide.King))
 
-        if CastleSide.Queen in castling_writes:
+        if CastleSide.Queen in castling_rights:
             clear = True
-            for dx in range(1, 3):
+            for dx in range(1, 4):
                 x = self.pos.x - dx
                 y = self.pos.y
 
@@ -57,7 +57,7 @@ class King(Piece):
 
                 move = self._move_for_position(board, x, y)
                 board_after_move = board.make_move(move)
-                if board_after_move.is_check_for(self.colour):
+                if dx < 3 and board_after_move.is_check_for(self.colour):
                     clear = False
                     break
 

python/src/logic/pieces/knight.py

@@ -16,7 +16,7 @@ class Knight(Piece):
             if move is not None:
                 ret.append(move)
 
-        if not looking_for_check and board.is_check_for(self.colour):
+        if not looking_for_check:# and board.is_check_for(self.colour):
             return self.keep_only_blocking(ret, board)
 
         return ret

python/src/logic/pieces/pawn.py

@@ -0,0 +1,80 @@
+from logic.move import Move
+from logic.pieces.bishop import Bishop
+from logic.pieces.knight import Knight
+from logic.pieces.piece import Colour, Piece
+from logic.pieces.queen import Queen
+from logic.pieces.rook import Rook
+from logic.position import Position
+
+class Pawn(Piece):
+    def legal_moves(self, board, / , looking_for_check = False) -> list[Move]:
+        ret = []
+
+        # can we capture to the left?
+        if self.pos.x > 0 and (
+            (self.colour == Colour.WHITE and (capturable_piece := board.piece_at(self.pos.x - 1, self.pos.y + 1)))
+            or
+            (self.colour == Colour.BLACK and (capturable_piece := board.piece_at(self.pos.x - 1, self.pos.y - 1)))
+        ):
+            if capturable_piece.colour != self.colour:
+                if (self.colour == Colour.WHITE and capturable_piece.pos.y == 7) or (self.colour == Colour.BLACK and capturable_piece.pos.y == 0):
+                    for piece in [Queen, Knight, Bishop, Rook]:
+                        ret.append(Move(self, capturable_piece.pos, is_capturing=True, promotes_to=piece))
+                else:
+                    ret.append(Move(self, capturable_piece.pos, is_capturing = True))
+
+        # can we capture to the right?
+        if self.pos.x < 7 and (
+            (self.colour == Colour.WHITE and (capturable_piece := board.piece_at(self.pos.x + 1, self.pos.y + 1)))
+            or
+            (self.colour == Colour.BLACK and (capturable_piece := board.piece_at(self.pos.x + 1, self.pos.y - 1)))
+        ):
+            if capturable_piece.colour != self.colour:
+                if (self.colour == Colour.WHITE and capturable_piece.pos.y == 7) or (self.colour == Colour.BLACK and capturable_piece.pos.y == 0):
+                    for piece in [Queen, Knight, Bishop, Rook]:
+                        ret.append(Move(self, capturable_piece.pos, is_capturing=True, promotes_to=piece))
+                else:
+                    ret.append(Move(self, capturable_piece.pos, is_capturing = True))
+
+        # -- Can we capture en passant?
+        if board._en_passant_target is not None and \
+            board._en_passant_target.pos.y == self.pos.y and (
+                board._en_passant_target.pos.x == self.pos.x - 1
+                or board._en_passant_target.pos.x == self.pos.x + 1
+        ):
+            if board._en_passant_target.colour != self.colour:
+                old_pos = board._en_passant_target.pos
+                new_pos = Position(old_pos.x, old_pos.y + (1 if self.colour == Colour.WHITE else -1))
+                ret.append(Move(self, new_pos, is_capturing = True, en_passant = True))
+
+        # -- Normal moves
+        if self.colour == Colour.WHITE:
+            for dy in range(1, 3 if self.pos.y == 1 else 2):
+                y = self.pos.y + dy
+                if y > 7 or board.piece_at(self.pos.x, y):
+                    break
+                pos = Position(self.pos.x, y)
+                if y == 7:
+                    for piece in [Queen, Knight, Bishop, Rook]:
+                        ret.append(Move(self, pos, promotes_to=piece))
+                else:
+                    ret.append(Move(self, pos, becomes_en_passant_target=dy==2))
+        else:
+            for dy in range(1, 3 if self.pos.y == 6 else 2):
+                y = self.pos.y - dy
+                if y < 0 or board.piece_at(self.pos.x, y):
+                    break
+                pos = Position(self.pos.x, y)
+                if y == 0:
+                    for piece in [Queen, Knight, Bishop, Rook]:
+                        ret.append(Move(self, pos, promotes_to=piece))
+                else:
+                    ret.append(Move(self, pos, becomes_en_passant_target=dy==2))
+
+        if not looking_for_check:# and board.is_check_for(self.colour):
+            return self.keep_only_blocking(ret, board)
+
+        return ret
+
+    def letter(self):
+        return "p"

python/src/logic/pieces/queen.py

@@ -29,7 +29,7 @@ class Queen(Piece):
         # looking north
         ret.extend(self._look_direction(board, 0, 1))
 
-        if not looking_for_check and board.is_check_for(self.colour):
+        if not looking_for_check:# and board.is_check_for(self.colour):
             return self.keep_only_blocking(ret, board)
 
         return ret

python/src/logic/pieces/rook.py

@@ -17,7 +17,7 @@ class Rook(Piece):
         # looking north
         ret.extend(self._look_direction(board, 0, 1))
 
-        if not looking_for_check and board.is_check_for(self.colour):
+        if not looking_for_check:# and board.is_check_for(self.colour):
             return self.keep_only_blocking(ret, board)
 
         return ret

python/src/logic/position.py

@@ -17,6 +17,14 @@ class Position:
         return x >= Position._MIN_POS and x <= Position._MAX_POS \
             and y >= Position._MIN_POS and y <= Position._MAX_POS
 
+    @staticmethod
+    def from_algebraic(square: str) -> "Position":
+        assert len(square) == 2, f"'{square}' is malformed"
+        x = Position._FILES.index(square[0])
+        y = Position._RANKS.index(int(square[1]))
+
+        return Position(x, y)
+
     def to_algebraic(self) -> str:
         return f"{Position._FILES[self.x]}{Position._RANKS[self.y]}"
 

python/src/main.py

@@ -0,0 +1,27 @@
+import time
+from pprint import pprint
+from tqdm import tqdm
+
+from ai.ai import move_generation_test
+from controller.controller import Controller
+from logic.board import INITIAL_BOARD, Board
+from logic.position import Position
+from view.gui import GUI
+from view.tui import TUI
+
+from ai.ai import peft
+
+if __name__ == "__main__":
+    board = INITIAL_BOARD
+
+    pos = "rnbq1k1r/pp1Pbppp/2p5/8/2B5/8/PPP1NnPP/RNBQK2R w KQ - 1 8"
+    board = Board.setup_FEN_position(pos)
+
+    view = GUI()
+
+    controller = Controller(board, view)
+
+    # view.show()
+    # exit()
+
+    peft(pos)

python/tests/fen.py

@@ -0,0 +1,30 @@
+import unittest
+
+import sys
+sys.path.append('src') # you must execute pytest from the stickfosh dir for this to work
+
+from logic.board import Board
+
+class FENTests(unittest.TestCase):
+    def testInitialPosition(self):
+        pos = "rnbqkbnr/pppppppp/8/8/8/8/PPPPPPPP/RNBQKBNR w KQkq - 0 1"
+        self.assertEqual(pos, Board.setup_FEN_position(pos).to_fen_string())
+
+    def testRandomPositions(self):
+        pos = "r1bk3r/p2pBpNp/n4n2/1p1NP2P/6P1/3P4/P1P1K3/q5b1 b Qk - 0 1"
+        self.assertEqual(pos, Board.setup_FEN_position(pos).to_fen_string())
+
+        pos = "rnbqkbnr/pppppppp/8/8/4P3/8/PPPP1PPP/RNBQKBNR b KQkq e3 0 1"
+        self.assertEqual(pos, Board.setup_FEN_position(pos).to_fen_string())
+
+        pos = "4k2r/6r1/8/8/8/8/3R4/R3K3 w Qk - 0 1"
+        self.assertEqual(pos, Board.setup_FEN_position(pos).to_fen_string())
+
+        pos = "8/8/8/4p1K1/2k1P3/8/8/8 b - - 0 1"
+        self.assertEqual(pos, Board.setup_FEN_position(pos).to_fen_string())
+
+        pos = "8/5k2/3p4/1p1Pp2p/pP2Pp1P/P4P1K/8/8 b - - 99 50"
+        self.assertEqual(pos, Board.setup_FEN_position(pos).to_fen_string())
+
+
+

python/tests/position.py

@@ -0,0 +1,30 @@
+import unittest
+
+import sys
+sys.path.append('src') # you must execute pytest from the stickfosh dir for this to work
+
+from logic.position import Position
+
+class PositionTests(unittest.TestCase):
+    def testXY2Algebraic(self):
+        self.assertEqual(Position(0, 0).to_algebraic(), "a1")
+        self.assertEqual(Position(1, 0).to_algebraic(), "b1")
+
+        self.assertEqual(Position(2, 1).to_algebraic(), "c2")
+        self.assertEqual(Position(4, 2).to_algebraic(), "e3")
+
+        self.assertEqual(Position(7, 7).to_algebraic(), "h8")
+
+    def testAlgebraic2XY(self):
+        self.assertEqual(Position.from_algebraic("a1"), Position(0, 0))
+        self.assertEqual(Position.from_algebraic("b1"), Position(1, 0))
+
+        self.assertEqual(Position.from_algebraic("c2"), Position(2, 1))
+        self.assertEqual(Position.from_algebraic("e3"), Position(4, 2))
+
+        self.assertEqual(Position.from_algebraic("h8"), Position(7, 7))
+
+        self.assertRaises(AssertionError, lambda : Position.from_algebraic("a11"))
+
+        self.assertRaises(ValueError, lambda : Position.from_algebraic("j1"))
+        self.assertRaises(ValueError, lambda : Position.from_algebraic("a9"))

src/logic/pieces/pawn.py

@@ -1,43 +0,0 @@
-from logic.move import Move
-from logic.pieces.piece import Colour, Piece
-from logic.position import Position
-
-class Pawn(Piece):
-    def legal_moves(self, board, / , looking_for_check = False) -> list[Move]:
-        ret = []
-
-        # can we capture to the left?
-        if self.pos.x > 0 and (
-            (self.colour == Colour.WHITE and (capturable_piece := board.piece_at(self.pos.x - 1, self.pos.y + 1)))
-            or
-            (self.colour == Colour.BLACK and (capturable_piece := board.piece_at(self.pos.x - 1, self.pos.y - 1)))
-        ):
-            if capturable_piece.colour != self.colour:
-                ret.append(Move(self, capturable_piece.pos, is_capturing = True))
-
-        # can we capture to the right?
-        if self.pos.x < 7 and (
-            (self.colour == Colour.WHITE and (capturable_piece := board.piece_at(self.pos.x + 1, self.pos.y + 1)))
-            or
-            (self.colour == Colour.BLACK and (capturable_piece := board.piece_at(self.pos.x + 1, self.pos.y - 1)))
-        ):
-            if capturable_piece.colour != self.colour:
-                ret.append(Move(self, capturable_piece.pos, is_capturing = True))
-
-        if self.colour == Colour.WHITE:
-            for dy in range(1, 3 if self.pos.y == 1 else 2):
-                if self.pos.y + dy > 7 or board.piece_at(self.pos.x, self.pos.y + dy):
-                    break
-                pos = Position(self.pos.x, self.pos.y + dy)
-                ret.append(Move(self, pos))
-        else:
-            for dy in range(1, 3 if self.pos.y == 6 else 2):
-                if self.pos.y - dy < 0 or board.piece_at(self.pos.x, self.pos.y - dy):
-                    break
-                pos = Position(self.pos.x, self.pos.y - dy)
-                ret.append(Move(self, pos))
-
-        if not looking_for_check and board.is_check_for(self.colour):
-            return self.keep_only_blocking(ret, board)
-
-        return ret

src/main.py

@@ -1,14 +0,0 @@
-from controller.controller import Controller
-from logic.board import Board
-from view.gui import GUI
-from view.tui import TUI
-
-if __name__ == "__main__":
-    initial_board_position = "rnbqkbnr/pppppppp/8/8/8/8/PPPPPPPP/RNBQKBNR w KQkq - 0 1"
-    board = Board.setup_FEN_position(initial_board_position)
-
-    view = GUI()
-
-    controller = Controller(board, view)
-
-    view.show()