implement is_square_attacked and is_king_attacked

helper_scripts/generate_attacking_pawns.py

@@ -0,0 +1,89 @@
+#!/usr/bin/env python3
+
+def generate_pawn_attacked_by():
+    """
+    Generates a list of 64 u64 bitboards for each color (White, Black),
+    where each bitboard represents the squares FROM WHICH a pawn
+    can attack a given TARGET square.
+    Uses Little-Endian File-Rank (LEFR) mapping: A1=0, H1=7, A2=8, ..., H8=63.
+
+    Returns:
+        [[u64; 64]; 2]  (represented as a list of two lists)
+        Index 0: White attackers (squares where a White pawn attacks the target)
+        Index 1: Black attackers (squares where a Black pawn attacks the target)
+    """
+
+    # all_attacks[0] = White, all_attacks[1] = Black
+    all_attacks = [[], []]
+
+    for sq in range(64):
+        rank = sq // 8
+        file = sq % 8
+
+        white_attackers_bb = 0
+        black_attackers_bb = 0
+
+        # --- White Attackers (Index 0) ---
+        # A white pawn attacks "up" the board to reach the target square 'sq'.
+        # This means the attacking pawn must be "below" 'sq'.
+        # We only check if the target is not on the 1st rank
+        if rank > 0:
+            # Attacker from Down-Left (relative to target sq)
+            # Not possible if target is on the A-file
+            if file > 0:
+                white_attackers_bb |= (1 << (sq - 9))
+
+            # Attacker from Down-Right (relative to target sq)
+            # Not possible if target is on the H-file
+            if file < 7:
+                white_attackers_bb |= (1 << (sq - 7))
+
+        # --- Black Attackers (Index 1) ---
+        # A black pawn attacks "down" the board to reach the target square 'sq'.
+        # This means the attacking pawn must be "above" 'sq'.
+        # We only check if the target is not on the 8th rank
+        if rank < 7:
+            # Attacker from Up-Left (relative to target sq)
+            # Not possible if target is on the A-file
+            if file > 0:
+                black_attackers_bb |= (1 << (sq + 7))
+
+            # Attacker from Up-Right (relative to target sq)
+            # Not possible if target is on the H-file
+            if file < 7:
+                black_attackers_bb |= (1 << (sq + 9))
+
+        all_attacks[0].append(white_attackers_bb)
+        all_attacks[1].append(black_attackers_bb)
+
+    return all_attacks
+
+def print_rust_array(attacks_by_color, const_name):
+    """
+    Prints the list of attack bitboards as a nested Rust array.
+    """
+    print(f"pub const {const_name}: [[u64; 64]; 2] = [")
+
+    # --- Print White Attacks ---
+    print("    [ // Color 0: White (Squares a White pawn attacks FROM)")
+    for i, attacks_bb in enumerate(attacks_by_color[0]):
+        raw_binary_string = f"{attacks_bb:064b}"
+        chunks = [raw_binary_string[i:i+8] for i in range(0, 64, 8)]
+        binary_string = f"0b{'_'.join(chunks)}"
+        print(f"        {binary_string}, // Target Square {i} ({'ABCDEFGH'[i%8]}{i//8 + 1})")
+    print("    ],")
+
+    # --- Print Black Attacks ---
+    print("    [ // Color 1: Black (Squares a Black pawn attacks FROM)")
+    for i, attacks_bb in enumerate(attacks_by_color[1]):
+        raw_binary_string = f"{attacks_bb:064b}"
+        chunks = [raw_binary_string[i:i+8] for i in range(0, 64, 8)]
+        binary_string = f"0b{'_'.join(chunks)}"
+        print(f"        {binary_string}, // Target Square {i} ({'ABCDEFGH'[i%8]}{i//8 + 1})")
+    print("    ]")
+
+    print("];")
+
+if __name__ == "__main__":
+    attacks = generate_pawn_attacked_by()
+    print_rust_array(attacks, "ATTACKING_PAWNS")