Files
katrain-qt/board.py
T

141 lines
4.8 KiB
Python

from move import Move
class IllegalMoveException(Exception):
pass
class Board:
_move_id_counter = 0 # used to make a map to all moves across all games
def __init__(self, board_size=19):
self.board_size = board_size
self.root = Move(1, (None, None)) # root is 1=white so black is first
self.root.id = -1
self.current_move = self.root
self.all_moves = {}
self._init_chains()
# -- move tree functions --
def _init_chains(self):
self.board = [[-1 for x in range(self.board_size)] for y in range(self.board_size)] # board pos -> chain id
self.chains = [] # chain id -> chain
self.prisoners = []
self.last_capture = []
try:
for m in self.moves:
self._validate_move_and_update_chains(m, True) # ignore ko since we didn't know if it was forced
except IllegalMoveException as e:
raise Exception(f"Unexpected illegal move ({str(e)})")
def _validate_move_and_update_chains(self, move, ignore_ko):
def neighbours(moves):
return {
self.board[m.coords[1] + dy][m.coords[0] + dx]
for m in moves
for dy, dx in [(-1, 0), (1, 0), (0, -1), (0, 1)]
if 0 <= m.coords[0] + dx < self.board_size and 0 <= m.coords[1] + dy < self.board_size
}
ko_or_snapback = len(self.last_capture) == 1 and self.last_capture[0] == move
self.last_capture = []
if move.is_pass:
return
if self.board[move.coords[1]][move.coords[0]] != -1:
raise IllegalMoveException("Space occupied")
nb_chains = list({c for c in neighbours([move]) if c >= 0 and self.chains[c][0].player == move.player})
if nb_chains:
this_chain = nb_chains[0]
self.board = [
[nb_chains[0] if sq in nb_chains else sq for sq in line] for line in self.board
] # merge chains connected by this move
for oc in nb_chains[1:]:
self.chains[nb_chains[0]] += self.chains[oc]
self.chains[oc] = []
self.chains[nb_chains[0]].append(move)
else:
this_chain = len(self.chains)
self.chains.append([move])
self.board[move.coords[1]][move.coords[0]] = this_chain
opp_nb_chains = {c for c in neighbours([move]) if c >= 0 and self.chains[c][0].player != move.player}
for c in opp_nb_chains:
if -1 not in neighbours(self.chains[c]):
self.last_capture += self.chains[c]
for om in self.chains[c]:
self.board[om.coords[1]][om.coords[0]] = -1
self.chains[c] = []
if ko_or_snapback and len(self.last_capture) == 1 and not ignore_ko:
raise IllegalMoveException("Ko")
self.prisoners += self.last_capture
if -1 not in neighbours(self.chains[this_chain]):
raise IllegalMoveException("Suicide")
# Play a Move from the current position, returns false if invalid.
def play(self, move, ignore_ko=False):
try:
self._validate_move_and_update_chains(move, ignore_ko)
except IllegalMoveException as e:
self._init_chains() # restore
raise
move = self.current_move.play(move) # traverse or append
if not move.id:
move.id = Board._move_id_counter
Board._move_id_counter += 1
self.all_moves[move.id] = move
self.current_move = move
return move
def undo(self):
if self.current_move != self.root:
self.current_move = self.current_move.parent
self._init_chains()
@property
def moves(self) -> list: # flat list of moves to current
moves = []
p = self.current_move
while p != self.root:
moves.append(p)
p = p.parent
return moves[::-1]
@property
def current_player(self):
return self.current_move.player
# --analysis
def store_analysis(self, json):
if json["id"].starts_with("PASS_"):
id = int(json["id"].lstrip("PASS_"))
else:
id = int(json["id"])
move = self.all_moves.get(id)
if move: # else this should be old
move.set_analysis(json)
else:
print("WARNING: ORPHANED ANALYSIS FOUND - RECENT NEW GAME?")
# -- board visualization etc
# ko: single capture and
# other not allowed: suicide
@property
def stones(self):
return sum(self.chains, [])
def sgf(self):
return "SGF[]"
def __str__(self):
return (
"\n".join("".join("BW"[self.chains[c][0].player] if c >= 0 else "-" for c in l) for l in self.board)
+ f"\ncaptures: {self.prisoners}"
)