def _get_king_movement_area(self, board, sq1, king_sq):
# Determines the number of squares the (enemy) king is limited to
sq1_file_index = chess.file_index(sq1)
sq1_rank_index = chess.rank_index(sq1)
king_file_index = chess.file_index(king_sq)
king_rank_index = chess.rank_index(king_sq)
if (sq1_file_index == king_file_index
or sq1_rank_index == king_rank_index):
return float("inf")
if (king_file_index < sq1_file_index):
if (king_rank_index < sq1_rank_index):
# King SW of rook
return (sq1_file_index * sq1_rank_index)
else:
# King NW of rook
return (sq1_file_index * (7 - sq1_rank_index))
else:
if (king_rank_index < sq1_rank_index):
# King SE of rook
return ((7 - sq1_file_index) * sq1_rank_index)
else:
# King NE of rook
return ((7 - sq1_file_index) * (7 - sq1_rank_index))
def _distance(self, board, sq1, sq2):
assert (sq1 != sq2)
sq1_file_index = chess.file_index(sq1)
sq1_rank_index = chess.rank_index(sq1)
sq2_file_index = chess.file_index(sq2)
sq2_rank_index = chess.rank_index(sq2)
return (abs(sq1_file_index - sq2_file_index) +
abs(sq1_rank_index - sq2_rank_index))
def _is_piece_protected_by_king(self, board, sq1, king_sq):
assert (sq1 != king_sq)
sq1_file_index = chess.file_index(sq1)
sq1_rank_index = chess.rank_index(sq1)
king_file_index = chess.file_index(king_sq)
king_rank_index = chess.rank_index(king_sq)
return (abs(sq1_file_index - king_file_index) <= 1
and abs(sq1_rank_index - king_rank_index) <= 1)
def _is_knight_distance_away(self, board, sq1, sq2):
assert (sq1 != sq2)
sq1_file_index = chess.file_index(sq1)
sq1_rank_index = chess.rank_index(sq1)
sq2_file_index = chess.file_index(sq2)
sq2_rank_index = chess.rank_index(sq2)
file_diff = abs(sq1_file_index - sq2_file_index)
rank_diff = abs(sq1_rank_index - sq2_rank_index)
return (file_diff == 1 and rank_diff == 2) or (file_diff == 2
and rank_diff == 1)
def _both_kings_same_quadrant(self, board, queen_sq, king_sq,
enemy_king_sq):
queen_file_index = chess.file_index(queen_sq)
queen_rank_index = chess.rank_index(queen_sq)
king_file_index = chess.file_index(king_sq)
king_rank_index = chess.rank_index(king_sq)
enemy_king_file_index = chess.file_index(enemy_king_sq)
enemy_king_rank_index = chess.rank_index(enemy_king_sq)
QUAD_SW = 1
QUAD_SE = 2
QUAD_NW = 3
QUAD_NE = 4
quad_king = None
quad_enemy_king = None
if (king_file_index < queen_file_index):
if (king_rank_index < queen_rank_index):
# King SW of rook
quad_king = QUAD_SW
elif (king_rank_index > queen_rank_index):
# King NW of rook
quad_king = QUAD_NW
elif (king_file_index > queen_file_index):
if (king_rank_index < queen_rank_index):
# King SE of rook
quad_king = QUAD_SE
elif (king_rank_index > queen_rank_index):
# King NE of rook
quad_king = QUAD_NE
if (enemy_king_file_index < queen_file_index):
if (enemy_king_rank_index < queen_rank_index):
# Enemy king SW of rook
quad_enemy_king = QUAD_SW
elif (enemy_king_rank_index > queen_rank_index):
# Enemy king NW of rook
quad_enemy_king = QUAD_NW
elif (enemy_king_file_index > queen_file_index):
if (enemy_king_rank_index < queen_rank_index):
# Enemy king SE of rook
quad_enemy_king = QUAD_SE
elif (enemy_king_rank_index > queen_rank_index):
# Enemy king NE of rook
quad_enemy_king = QUAD_NE
return quad_king and quad_enemy_king and quad_king == quad_enemy_king
def _is_king_picking(self, board, sq1, king_sq, enemy_king_sq):
sq1_file_index = chess.file_index(sq1)
sq1_rank_index = chess.rank_index(sq1)
king_file_index = chess.file_index(king_sq)
king_rank_index = chess.rank_index(king_sq)
enemy_king_file_index = chess.file_index(enemy_king_sq)
enemy_king_rank_index = chess.rank_index(enemy_king_sq)
if (enemy_king_file_index < sq1_file_index):
if (enemy_king_rank_index < sq1_rank_index):
# King SW of rook
if (king_file_index < sq1_file_index
and king_rank_index == sq1_rank_index):
return True
if (king_rank_index < sq1_rank_index
and king_file_index == sq1_file_index):
return True
else:
# King NW of rook
if (king_file_index < sq1_file_index
and king_rank_index == sq1_rank_index):
return True
if (king_rank_index > sq1_rank_index
and king_file_index == sq1_file_index):
return True
else:
if (enemy_king_rank_index < sq1_rank_index):
# King SE of rook
if (king_file_index > sq1_file_index
and king_rank_index == sq1_rank_index):
return True
if (king_rank_index < sq1_rank_index
and king_file_index == sq1_file_index):
return True
else:
# King NE of rook
if (king_file_index > sq1_file_index
and king_rank_index == sq1_rank_index):
return True
if (king_rank_index > sq1_rank_index
and king_file_index == sq1_file_index):
return True
return False
def _get_finish_move_endgame_1(self, board, rook_sq, king_sq,
enemy_king_sq):
rook_file_index = chess.file_index(rook_sq)
rook_rank_index = chess.rank_index(rook_sq)
king_file_index = chess.file_index(king_sq)
king_rank_index = chess.rank_index(king_sq)
enemy_king_file_index = chess.file_index(enemy_king_sq)
enemy_king_rank_index = chess.rank_index(enemy_king_sq)
move = None
if (king_rank_index == enemy_king_rank_index):
if (abs(king_file_index - enemy_king_file_index) == 2):
if (abs(rook_rank_index - king_rank_index) == 1):
move = chess.SQUARE_NAMES[rook_sq] + chess.SQUARE_NAMES[
rook_rank_index * 8 + king_file_index]
if (king_file_index == enemy_king_file_index):
if (abs(king_rank_index - enemy_king_rank_index) == 2):
if (abs(rook_file_index - king_file_index) == 1):
move = chess.SQUARE_NAMES[rook_sq] + chess.SQUARE_NAMES[
king_rank_index * 8 + rook_sq % 8]
return move
def _get_finish_move_endgame_2(self, board, queen_sq, king_sq,
enemy_king_sq):
queen_file_index = chess.file_index(queen_sq)
queen_rank_index = chess.rank_index(queen_sq)
king_file_index = chess.file_index(king_sq)
king_rank_index = chess.rank_index(king_sq)
enemy_king_file_index = chess.file_index(enemy_king_sq)
enemy_king_rank_index = chess.rank_index(enemy_king_sq)
move = None
if (queen_sq == chess.E2) and (king_sq == chess.E1) and (enemy_king_sq
== chess.G1):
return "e2d2"
elif (queen_sq == chess.D2) and (king_sq
== chess.D1) and (enemy_king_sq
== chess.B1):
return "d2e2"
elif (queen_sq == chess.B4) and (king_sq
== chess.A4) and (enemy_king_sq
== chess.A2):
return "b4b5"
elif (queen_sq == chess.B5) and (king_sq
== chess.A5) and (enemy_king_sq
== chess.A7):
return "b5b4"
elif (queen_sq == chess.D7) and (king_sq
== chess.D8) and (enemy_king_sq
== chess.B8):
return "d7e7"
elif (queen_sq == chess.E7) and (king_sq
== chess.E8) and (enemy_king_sq
== chess.G8):
return "e7d7"
elif (queen_sq == chess.G5) and (king_sq
== chess.H5) and (enemy_king_sq
== chess.H7):
return "g5g4"
elif (queen_sq == chess.G4) and (king_sq
== chess.G4) and (enemy_king_sq
== chess.H2):
return "g4g5"
if (queen_sq == chess.E2) and (king_sq == chess.E1) and (enemy_king_sq
== chess.H1):
return "e2g4"
elif (queen_sq == chess.D2) and (king_sq
== chess.D1) and (enemy_king_sq
== chess.A1):
return "d2b4"
elif (queen_sq == chess.B4) and (king_sq
== chess.A4) and (enemy_king_sq
== chess.A1):
return "b4d2"
elif (queen_sq == chess.B5) and (king_sq
== chess.A5) and (enemy_king_sq
== chess.A8):
return "b5d7"
elif (queen_sq == chess.D7) and (king_sq
== chess.D8) and (enemy_king_sq
== chess.A8):
return "d7b5"
elif (queen_sq == chess.E7) and (king_sq
== chess.E8) and (enemy_king_sq
== chess.H8):
return "e7g5"
elif (queen_sq == chess.G5) and (king_sq
== chess.H5) and (enemy_king_sq
== chess.H8):
return "g5e7"
elif (queen_sq == chess.G4) and (king_sq
== chess.H4) and (enemy_king_sq
== chess.H1):
return "g4e2"
if (queen_sq == chess.D2) and (king_sq == chess.E1) and (enemy_king_sq
== chess.H1):
return "e1f2"
elif (queen_sq == chess.E2) and (king_sq
== chess.D1) and (enemy_king_sq
== chess.A1):
return "d1c2"
elif (queen_sq == chess.B5) and (king_sq
== chess.A4) and (enemy_king_sq
== chess.A1):
return "a4b3"
elif (queen_sq == chess.B4) and (king_sq
== chess.A5) and (enemy_king_sq
== chess.A8):
return "a5b6"
elif (queen_sq == chess.E7) and (king_sq
== chess.D8) and (enemy_king_sq
== chess.A8):
return "d8c7"
elif (queen_sq == chess.D7) and (king_sq
== chess.E8) and (enemy_king_sq
== chess.H8):
return "e8f7"
elif (queen_sq == chess.G4) and (king_sq
== chess.H5) and (enemy_king_sq
== chess.H8):
return "h5g6"
elif (queen_sq == chess.G5) and (king_sq
== chess.H4) and (enemy_king_sq
== chess.H1):
return "h4g3"
return move
