from fast_P_nim import P


def safe_int_parse(s):
    try:
        return int(s)
    except ValueError:
        return -1


def display_game(game: dict) -> None:
    for i in range(game['size']):
        if game['board'][i]:
            print(f'{i+1:02d}', end="")
        else:
            print('  ', end="")
        if i + 1 != game['size']:
            print('-', end="")
    print()


def valid_move(game: dict, i: int):
    if i >= game['size'] or i < 0:
        return False
    if game['board'][i]:
        if i > 0:
            if i < game['size']-1:
                return game['board'][i-1] or game['board'][i+1]
            else:
                return game['board'][i-1]
        else:
            if i < game['size']-1:
                return game['board'][i+1]
            else:
                return True


def make_move(game: dict, i: int):
    gs = game['board'].copy()
    gs[i] = False
    if i > 0:
        gs[i-1] = not gs[i-1]
    if i < game['size']-1:
        gs[i+1] = not gs[i+1]
    return gs


def get_nimber(gs: list) -> int:
    n = len(gs)
    nimber_so_far = 0
    path_size = 0
    for i in range(n):
        if gs[i]:
            path_size += 1
        else:
            if path_size == 1 and n != 1:
                path_size = 0
            nimber_so_far = nimber_so_far ^ P(path_size)
            path_size = 0
    if path_size == 1 and n != 1:
        path_size = 0
    nimber_so_far = nimber_so_far ^ P(path_size)
    return nimber_so_far


def i_have_won(game: dict) -> bool:
    for i in range(game['size']):
        if valid_move(game, i):
            return False
    return True


def find_move(game: dict) -> int:
    game_state_orig = game['board'].copy()
    for i in range(game['size']):
        if valid_move(game, i):
            gs = make_move(game, i)
            if get_nimber(gs) == 0:
                return i
    raise Exception("I have been beat!")


def new_game(size: int) -> dict:
    game = {}
    game['board'] = [True] * size
    game['human_turn'] = not P(size) > 0
    game['size'] = size
    game['version'] = '0.0.0'
    game['finished'] = False
    game['winner'] = ""
    game['turn'] = 1
    return game


def main():
    n = int(input("Path size to play on> "))
    game = new_game(n)

    if game['human_turn']:
        print("You can play first!")
    else:
        print("I'll play first!")

    while True:
        display_game(game)
        if game['human_turn']:
            if i_have_won(game):
                print("You're out of moves. I win!")
                game['finished'] = True
                game['winner'] = "Computer"
                break
            game['human_turn'] = False
            i = -1 # placeholder
            while True:
                i = safe_int_parse(input("Make your move> ")) - 1
                if valid_move(game, i):
                    break
                print("Hey! That's not allowed!")
                display_game(game)
            game['turn'] += 1
            game['board'] = make_move(game, i)
        else:
            game['human_turn'] = True
            i = find_move(game)
            print(f"Hmm... I'll toggle {i + 1}")
            game['turn'] += 1
            game['board'] = make_move(game, i)

    print('-'*8)
    for key, val in game.items():
        print(f'{key}: {val}')

if __name__ == "__main__":
    main()