import random 
from collections import defaultdict
from itertools import combinations
import time

# Define card ranks and their order for runs    
RANK_ORDER = {str(n): n for n in range(2, 11)}
RANK_ORDER.update({"A": 1, "J": 11, "Q": 12, "K": 13})

# Card, Deck, DiscardPile, Hand, Player, Game classes   
class Card:
    suits = ['♠', '♥', '♦', '♣']
    ranks = list(range(1, 11)) + ['J', 'Q', 'K']
    
    def __init__(self, rank, suit):
        self.rank = rank
        self.suit = suit

    @property
    def value(self):
        if isinstance(self.rank, int):
            return self.rank
        return 10 if self.rank in ['J', 'Q', 'K'] else 1  # Ace low

    def __repr__(self):
        return f"{self.rank}{self.suit}"


class Deck:
    def __init__(self):
        self.cards = [Card(rank, suit) for suit in Card.suits for rank in Card.ranks]
        random.seed(time.time())  # Seed random number generator with current time
        random.shuffle(self.cards)

    def draw(self):
        return self.cards.pop() if self.cards else None


class DiscardPile:
    def __init__(self):
        self.cards = []

    def top(self):
        return self.cards[-1] if self.cards else None

    def discard(self, card):
        self.cards.append(card)
    

class Hand:
    def __init__(self):
        self.cards = []

    def add(self, card):
        self.cards.append(card)

    def remove(self, card):
        self.cards.remove(card)

    def get_all_melds(self):
        return self.find_sets() + self.find_runs()

    def find_sets(self):
        groups = defaultdict(list)
        for c in self.cards:
            groups[c.rank].append(c)
        return [group for group in groups.values() if len(group) >= 3]

    def find_runs(self):
        runs = []
        suits = defaultdict(list)
        for c in self.cards:
            suits[c.suit].append(c)

        for suit, suited_cards in suits.items():
            sorted_cards = sorted(suited_cards, key=lambda c: RANK_ORDER[str(c.rank)])
            temp = [sorted_cards[0]]
            for i in range(1, len(sorted_cards)):
                prev = RANK_ORDER[str(sorted_cards[i - 1].rank)]
                curr = RANK_ORDER[str(sorted_cards[i].rank)]
                if curr == prev + 1:
                    temp.append(sorted_cards[i])
                else:
                    if len(temp) >= 3:
                        runs.append(temp)
                    temp = [sorted_cards[i]]
            if len(temp) >= 3:
                runs.append(temp)
        return runs

    def non_overlapping_meld_combos(self, all_melds):
        valid_combos = []
        for r in range(1, len(all_melds) + 1):
            for combo in combinations(all_melds, r):
                used = set()
                overlap = False
                for meld in combo:
                    for card in meld:
                        if card in used:
                            overlap = True
                            break
                        used.add(card)
                    if overlap:
                        break
                if not overlap:
                    valid_combos.append(combo)
        return valid_combos

    def best_meld_combo(self):
        all_melds = self.get_all_melds()
        combos = self.non_overlapping_meld_combos(all_melds)
        best = max(combos, key=lambda combo: len(set(c for meld in combo for c in meld)), default=[])
        return best

    def deadwood(self):
        """Returns list of cards not used in best meld combo."""
        used = set(c for meld in self.best_meld_combo() for c in meld)
        return [c for c in self.cards if c not in used]

    def deadwood_points(self):
        return sum(c.value for c in self.deadwood())

    def __repr__(self):
        return f"Hand({self.cards})"
    

class Player:
    def __init__(self, name):
        self.name = name
        self.hand = Hand()
        self.seen_discards = []

    def draw(self, deck, discard_pile, from_discard=False):
        card = discard_pile.top() if from_discard else deck.draw()
        if card:
            self.hand.add(card)
            if from_discard:
                discard_pile.cards.pop()
        return card

    def discard(self, discard_pile, card):
        self.hand.remove(card)
        discard_pile.discard(card)
        self.seen_discards.append(card) 
        
def choose_discard(self, discard_pile):
    hand = self.hand.cards
    best_melds = self.hand.best_meld_combo()
    used = set(c for meld in best_melds for c in meld)
    candidates = [c for c in hand if c not in used]

    # Avoid discarding cards that match recent discards (opponent may want them back)
    risky_ranks = {c.rank for c in self.seen_discards[-5:]}  # last few discards
    risky_suits = {c.suit for c in self.seen_discards[-5:]}

    def score(card):
        value_penalty = card.value
        suit_cluster = sum(1 for c in hand if c.suit == card.suit)
        rank_cluster = sum(1 for c in hand if abs(RANK_ORDER[str(c.rank)] - RANK_ORDER[str(card.rank)]) <= 2)
        risk_penalty = 5 if card.rank in risky_ranks or card.suit in risky_suits else 0
        return value_penalty + risk_penalty - (suit_cluster + rank_cluster)

    # Rank candidates by value and meld potential
    if candidates:
        return min(candidates, key=score)
    else:
        return max(hand, key=lambda c: c.value)


class Game:
    def __init__(self, players):
        self.deck = Deck()
        self.discard_pile = DiscardPile()
        self.players = players
        self.scores = {p.name: 0 for p in players}

    def deal(self):
        for _ in range(10):
            for player in self.players:
                player.hand.add(self.deck.draw())
        self.discard_pile.discard(self.deck.draw())

    def play_round(self):
        self.deal()
        turn = 0
        while True:
            player = self.players[turn % 2]
            print(f"\n{player.name}'s turn")
            self.take_turn(player)

            if player.hand.deadwood_points() == 0:
                print(f"{player.name} goes GIN!")
                self.score_round(player, gin=True)
                break
            elif player.hand.deadwood_points() <= 10:
                print(f"{player.name} knocks!")
                self.score_round(player, gin=False)
                break

            turn += 1

    def take_turn(self, player):
        # Simple AI: always draw from stock
        drawn = player.draw(self.deck, self.discard_pile, from_discard=False)
        print(f"{player.name} draws {drawn}")

        # Discard highest deadwood card
        deadwood = player.hand.deadwood()
        if deadwood:
            discard = max(deadwood, key=lambda c: c.value)
            player.discard(self.discard_pile, discard)
            print(f"{player.name} discards {discard}")

    def score_round(self, knocker, gin=False):
        opponent = [p for p in self.players if p != knocker][0]
        knocker_deadwood = knocker.hand.deadwood_points()
        opponent_deadwood = opponent.hand.deadwood_points()

        if gin:
            score = opponent_deadwood + 25
        elif opponent_deadwood <= knocker_deadwood:
            score = (knocker_deadwood - opponent_deadwood) + 25  # undercut
            self.scores[opponent.name] += score
            print(f"{opponent.name} undercuts! Scores {score}")
            return
        else:
            score = opponent_deadwood - knocker_deadwood

        self.scores[knocker.name] += score
        print(f"{knocker.name} scores {score}")

        print("\nScores:")
        for name, pts in self.scores.items():
            print(f"{name}: {pts}")

# Functions to detect melds outside classes
# Function to detect sets
def find_sets(cards):
    groups = defaultdict(list)
    for c in cards:
        groups[c.rank].append(c)
    return [group for group in groups.values() if len(group) >= 3]

# Function to detect runs
def find_runs(cards):
    runs = []
    # group by suit
    suits = defaultdict(list)
    for c in cards:
        suits[c.suit].append(c)

    for suit, suited_cards in suits.items():
        # sort by rank order
        sorted_cards = sorted(suited_cards, key=lambda c: RANK_ORDER[str(c.rank)])
        # scan for consecutive sequences
        temp = [sorted_cards[0]]
        for i in range(1, len(sorted_cards)):
            prev = RANK_ORDER[str(sorted_cards[i-1].rank)]
            curr = RANK_ORDER[str(sorted_cards[i].rank)]
            if curr == prev + 1:
                temp.append(sorted_cards[i])
            else:
                if len(temp) >= 3:
                    runs.append(temp)
                temp = [sorted_cards[i]]
        if len(temp) >= 3:
            runs.append(temp)
    return runs

def non_overlapping_meld_combos(all_melds):
    """
    Given a list of all possible melds (sets and runs),
    return all combinations where no card is used more than once.
    """
    valid_combos = []
    for r in range(1, len(all_melds) + 1):
        for combo in combinations(all_melds, r):
            used = set()
            overlap = False
            for meld in combo:
                for card in meld:
                    if card in used:
                        overlap = True
                        break
                    used.add(card)
                if overlap:
                    break
            if not overlap:
                valid_combos.append(combo)
    return valid_combos
  
# start a game with two players
if __name__ == "__main__":
    players = [Player("Alice"), Player("Bob")]
    game = Game(players)
    game.play_round()   
    # Further game logic would go here