liars-dice/engine.py

import random
from collections import Counter
from dataclasses import dataclass


@dataclass
class Bid:
    die_face: int
    num_dice: int


class EngineHandler:
    def on_game_started(self, game_state: "LiarsDiceEngine"):
        pass

    def on_new_round(self):
        pass

    def on_bid_placed(self, bid):
        pass

    def on_challenge_bid(self):
        pass

    def on_player_eliminated(self, player_index):
        pass

    def get_players_turn(self) -> Bid | None:
        pass


@dataclass
class LiarsDiceEngine:
    NUM_INITIAL_DICE = 5
    WILD_DIE_FACE = 1

    listener: EngineHandler
    num_players: int
    round_number: int
    wild_ones_variant: bool
    active_player_index: int
    current_bid: Bid | None
    dice: list[Counter[int]]

    @staticmethod
    def new_game(
        num_players: int, wild_ones_variant: bool, listener: EngineHandler
    ) -> "LiarsDiceEngine":
        return LiarsDiceEngine(
            num_players=num_players,
            active_player_index=random.randint(0, num_players - 1),
            wild_ones_variant=wild_ones_variant,
            current_bid=None,
            dice=[
                Counter([random.randint(1, 6) for _ in range(LiarsDiceEngine.NUM_INITIAL_DICE)])
                for _ in range(num_players)
            ],
            round_number=0,
            listener=listener,
        )

    def start_game(self) -> None:
        self.listener.on_game_started(self)

        while self.num_players > 1:
            self.new_round()

            while True:
                bid = self.listener.get_players_turn()
                if bid:
                    self.place_bid(bid)
                else:
                    self.challenge_current_bid()
                    break

    def new_round(self):
        self.current_bid = None
        self.active_player_index = self.active_player_index % self.num_players
        self.round_number += 1

        self.listener.on_new_round()

    def place_bid(self, bid: Bid):
        self.current_bid = bid
        self.listener.on_bid_placed(bid)
        self.active_player_index = (self.active_player_index + 1) % self.num_players

    def challenge_current_bid(self):
        self.listener.on_challenge_bid()

        losing_player_index = (
            self.active_player_index
            if self.is_current_bid_successful()
            else self.active_player_index - 1
        )

        num_dice_per_player = [c.total() for c in self.dice]

        if num_dice_per_player[losing_player_index] > 1:
            num_dice_per_player[losing_player_index] -= 1
        else:
            self.listener.on_player_eliminated(losing_player_index)

            self.num_players -= 1

            num_dice_per_player = [
                d for (i, d) in enumerate(num_dice_per_player) if i != losing_player_index
            ]

        self.active_player_index = losing_player_index

        self.dice = [
            Counter([random.randint(1, 6) for _ in range(num_dice_per_player[p])])
            for p in range(self.num_players)
        ]

    def is_current_bid_successful(self) -> bool:
        num_wild_dice = (
            self.num_all_dice_with_value(self.WILD_DIE_FACE) if self.wild_ones_variant else 0
        )
        return (
            self.num_all_dice_with_value(self.current_bid.die_face) + num_wild_dice
            >= self.current_bid.num_dice
        )

    @property
    def num_opponent_dice(self) -> int:
        return sum(c.total() for (i, c) in enumerate(self.dice) if i != self.active_player_index)

    @property
    def num_all_dice(self) -> int:
        return sum(c.total() for c in self.dice)

    def num_all_dice_with_value(self, die_face: int) -> int:
        return sum(c[die_face] for c in self.dice)