[Python] How to add chess move validation to my function?

I have this function that takes in a piece (e.g wR would be white rook), the row its on and the column and returns a list of coordinates that it can move to. However, I would like to make it so that if the player is in check, the moves are restricted so that they have to get out of check. (The board array updates dynamically).

board = [['bR', 'bN', 'bB', 'bQ', 'bK', 'bB', 'bN', 'bR'],
['bp', 'bp', 'bp', 'bp', 'bp', 'bp', 'bp', 'bp'],
['xx', 'xx', 'xx', 'xx', 'xx', 'xx', 'xx', 'xx'],
['xx', 'xx', 'xx', 'xx', 'xx', 'xx', 'xx', 'xx'],
['xx', 'xx', 'xx', 'xx', 'xx', 'xx', 'xx', 'xx'],
['xx', 'xx', 'xx', 'xx', 'xx', 'xx', 'xx', 'xx'],
['wp', 'wp', 'wp', 'wp', 'wp', 'wp', 'wp', 'wp'],
['wR', 'wN', 'wB', 'wK', 'wQ', 'wB', 'wN', 'wR']]

def get_valid_moves(piece, row, col):
global board
moves = []

if piece == 'wp':
# Movement rules for white pawn
if row > 0 and board[row - 1][col] == 'xx': # Move forward
moves.append((row - 1, col))
if row == 6 and board[row - 1][col] == 'xx' and board[row - 2][col] == 'xx':
moves.append((row - 2, col))
if row > 0 and col > 0 and board[row - 1][col - 1][0] == 'b':
moves.append((row - 1, col - 1))
if row > 0 and col < 7 and board[row - 1][col + 1][0] == 'b':
moves.append((row - 1, col + 1))
elif piece == 'bp':
# Movement rules for black pawn
if row < 7 and board[row + 1][col] == 'xx':
moves.append((row + 1, col))
if row == 1 and board[row + 1][col] == 'xx' and board[row + 2][col] == 'xx':
moves.append((row + 2, col))
if row < 7 and col > 0 and board[row + 1][col - 1][0] == 'w':
moves.append((row + 1, col - 1))
if row < 7 and col < 7 and board[row + 1][col + 1][0] == 'w':
moves.append((row + 1, col + 1))
elif piece == 'wR' or piece == 'bR':
# Movement rules for rook
for c in range(col - 1, -1, -1):
if board[row][c] == 'xx':
moves.append((row, c))
elif board[row][c][0] != piece[0]:
moves.append((row, c))
break
else:
break
for c in range(col + 1, 8):
if board[row][c] == 'xx':
moves.append((row, c))
elif board[row][c][0] != piece[0]:
moves.append((row, c))
break
else:
break
for r in range(row - 1, -1, -1):
if board[r][col] == 'xx':
moves.append((r, col))
elif board[r][col][0] != piece[0]:
moves.append((r, col))
break
else:
break
for r in range(row + 1, 8):
if board[r][col] == 'xx':
moves.append((r, col))
elif board[r][col][0] != piece[0]:
moves.append((r, col))
break
else:
break
elif piece == 'wB' or piece == 'bB':
# Movement rules for bishop
for i in range(1, min(8 - row, 8 - col)):
if board[row + i][col + i] == 'xx':
moves.append((row + i, col + i))
elif board[row + i][col + i][0] != piece[0]:
moves.append((row + i, col + i))
break
else:
break
for i in range(1, min(8 - row, col + 1)):
if board[row + i][col - i] == 'xx':
moves.append((row + i, col - i))
elif board[row + i][col - i][0] != piece[0]:
moves.append((row + i, col - i))
break
else:
break
for i in range(1, min(row + 1, 8 - col)):
if board[row - i][col + i] == 'xx':
moves.append((row - i, col + i))
elif board[row - i][col + i][0] != piece[0]:
moves.append((row - i, col + i))
break
else:
break
for i in range(1, min(row + 1, col + 1)):
if board[row - i][col - i] == 'xx':
moves.append((row - i, col - i))
elif board[row - i][col - i][0] != piece[0]:
moves.append((row - i, col - i))
break
else:
break
elif piece == 'wN' or piece == 'bN':
# Movement rules for knight
knight_moves = [(-1, -2), (-2, -1), (-2, 1), (-1, 2), (1, -2), (2, -1), (2, 1), (1, 2)]
for move in knight_moves:
new_row = row + move[0]
new_col = col + move[1]
if 0 <= new_row < 8 and 0 <= new_col < 8:
if board[new_row][new_col] == 'xx' or board[new_row][new_col][0] != piece[0]:
moves.append((new_row, new_col))
elif piece == 'wQ' or piece == 'bQ':
# Movement rules for queen
for c in range(col - 1, -1, -1):
if board[row][c] == 'xx':
moves.append((row, c))
elif board[row][c][0] != piece[0]:
moves.append((row, c))
break
else:
break
for c in range(col + 1, 8):
if board[row][c] == 'xx':
moves.append((row, c))
elif board[row][c][0] != piece[0]:
moves.append((row, c))
break
else:
break
# Vertical moves
for r in range(row - 1, -1, -1):
if board[r][col] == 'xx':
moves.append((r, col))
elif board[r][col][0] != piece[0]:
moves.append((r, col))
break
else:
break
for r in range(row + 1, 8):
if board[r][col] == 'xx':
moves.append((r, col))
elif board[r][col][0] != piece[0]:
moves.append((r, col))
break
else:
break
for i in range(1, min(8 - row, 8 - col)):
if board[row + i][col + i] == 'xx':
moves.append((row + i, col + i))
elif board[row + i][col + i][0] != piece[0]:
moves.append((row + i, col + i))
break
else:
break
for i in range(1, min(8 - row, col + 1)):
if board[row + i][col - i] == 'xx':
moves.append((row + i, col - i))
elif board[row + i][col - i][0] != piece[0]:
moves.append((row + i, col - i))
break
else:
break
for i in range(1, min(row + 1, 8 - col)):
if board[row - i][col + i] == 'xx':
moves.append((row - i, col + i))
elif board[row - i][col + i][0] != piece[0]:
moves.append((row - i, col + i))
break
else:
break
for i in range(1, min(row + 1, col + 1)):
if board[row - i][col - i] == 'xx':
moves.append((row - i, col - i))
elif board[row - i][col - i][0] != piece[0]:
moves.append((row - i, col - i))
break
else:
break
elif piece == 'wK' or piece == 'bK':
# Movement rules for king
king_moves = [(-1, -1), (-1, 0), (-1, 1), (0, -1), (0, 1), (1, -1), (1, 0), (1, 1)]
for move in king_moves:
new_row = row + move[0]
new_col = col + move[1]
if 0 <= new_row < 8 and 0 <= new_col < 8:
if board[new_row][new_col] == 'xx' or board[new_row][new_col][0] != piece[0]:
moves.append((new_row, new_col))

def find_king_coordinates(player_color):
for r in range(8):
for c in range(8):
if board[r][c] == f'{player_color}K':
return r, c

def is_check(player_color, king_row, king_col, board):
# Define possible directions of attack for different pieces
knight_moves = [(1, 2), (2, 1), (-1, -2), (-2, -1), (1, -2), (2, -1), (-1, 2), (-2, 1)]
directions = [(1, 0), (-1, 0), (0, 1), (0, -1), (1, 1), (-1, -1), (1, -1), (-1, 1)]

# Check for attacks by knights
for dr, dc in knight_moves:
if 0 <= king_row + dr < 8 and 0 <= king_col + dc < 8:
if board[king_row + dr][king_col + dc] == f'{player_color}N':
return True

# Check for attacks by rooks and queens (horizontal and vertical)
for dr, dc in directions[:4]:
r, c = king_row + dr, king_col + dc
while 0 <= r < 8 and 0 <= c < 8:
piece = board[r][c]
if piece[0] == player_color:
break
if piece == f'{player_color}R' or piece == f'{player_color}Q':
return True
if piece != 'xx':
break
r, c = r + dr, c + dc

# Check for attacks by bishops and queens (diagonal)
for dr, dc in directions[4:]:
r, c = king_row + dr, king_col + dc
while 0 <= r < 8 and 0 <= c < 8:
piece = board[r][c]
if piece[0] == player_color:
break
if piece == f'{player_color}B' or piece == f'{player_color}Q':
return True
if piece != 'xx':
break
r, c = r + dr, c + dc

# Check for attacks by pawns (only considering the two diagonals)
pawn_attacks = [(1, 1), (1, -1)] if player_color == 'w' else [(-1, 1), (-1, -1)]
for dr, dc in pawn_attacks:
if 0 <= king_row + dr < 8 and 0 <= king_col + dc < 8:
if board[king_row + dr][king_col + dc] == f'{player_color}p':
return True

return False # The king is not in check

if is_check(piece[0], find_king_coordinates(piece[0]), board):
temp_board = board
pass

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