Endgame-Analyzer/game_state.hpp

#include <cassert>
#include <algorithm>
#include <iterator>


template <size_t num_suits, size_t num_players, size_t hand_size, uint8_t max_draw_pile_size>
Action HanabiState<num_suits, num_players, hand_size, max_draw_pile_size>::clue() {
  assert(_num_clues > 0);
  --_num_clues;

  incr_turn();

  return Action {ActionType::clue, {}, {}};
}

template <size_t num_suits, size_t num_players, size_t hand_size, uint8_t max_draw_pile_size>
void HanabiState<num_suits, num_players, hand_size, max_draw_pile_size>::incr_turn() {
  _turn = (_turn + 1) % num_players;
}

template <size_t num_suits, size_t num_players, size_t hand_size, uint8_t max_draw_pile_size>
void HanabiState<num_suits, num_players, hand_size, max_draw_pile_size>::decr_turn() {
  _turn = (_turn + num_players - 1) % num_players;
}

template <std::size_t num_suits, std::size_t num_players, std::size_t hand_size, uint8_t max_draw_pile_size>
Action HanabiState<num_suits, num_players, hand_size, max_draw_pile_size>::play(std::uint8_t index) {
  assert(index < _hands[_turn].size());
  const Card card = _hands[_turn][index];
  assert(card.rank == _stacks[card.suit] - 1);

  --_stacks[card.suit];

  Action ret {ActionType::play, _hands[_turn][index], index};

  if (card.rank == 0) {
    // update clues if we played the last card of a stack
    _num_clues++;
  }

  draw(index);
  incr_turn();

  return ret;
}

template <std::size_t num_suits, std::size_t num_players, std::size_t hand_size, uint8_t max_draw_pile_size>
Action HanabiState<num_suits, num_players, hand_size, max_draw_pile_size>::discard(std::uint8_t index) {
  assert(index < _hands[_turn].size());
  assert(_num_clues != max_num_clues);

  _num_clues++;

  Action ret {ActionType::discard, _hands[_turn][index], index};

  draw(index);
  incr_turn();

  return ret;
}


template <std::size_t num_suits, std::size_t num_players, std::size_t hand_size, uint8_t max_draw_pile_size>
std::ostream& operator<<(std::ostream& os, const HanabiState<num_suits, num_players, hand_size, max_draw_pile_size> hanabi_state) {
  os << "Stacks: " << hanabi_state._stacks << std::endl;
  os << "Draw pile: ";
  for (const auto &[card, mul] : hanabi_state._draw_pile) {
      os << card;
      if (mul > 1) {
          os << " (" << +mul << ")";
      }
  }
  os << std::endl;
  os << "Hands: ";
  for (const auto& hand: hanabi_state._hands) {
      for (const auto &card: hand) {
          os << card << ", ";
      }
      os << " | ";
  }
  return os;
}

template <std::size_t num_suits, std::size_t num_players, std::size_t hand_size, uint8_t max_draw_pile_size>
void HanabiState<num_suits, num_players, hand_size, max_draw_pile_size>::draw(std::uint8_t index) {
  assert(index < _hands[_turn].size());

  _card_positions[_hands[_turn][index]] = trash_or_play_stack;

  // draw a new card if the draw pile is not empty
  if (!_draw_pile.empty()) {
    --_draw_pile_size;
    CardMultiplicity draw = _draw_pile.front();
    _draw_pile.pop_front();
    assert(draw.multiplicity > 0);
    if (draw.multiplicity > 1) {
      draw.multiplicity--;
      _draw_pile.push_back(draw);
    }
    _hands[_turn][index] = draw.card;
    _card_positions[draw.card] = _turn;
  }
}

template <std::size_t num_suits, std::size_t num_players, std::size_t hand_size, uint8_t max_draw_pile_size>
void HanabiState<num_suits, num_players, hand_size, max_draw_pile_size>::revert_draw(std::uint8_t index, Card card) {
  assert(index < _hands[_turn].size());

  _card_positions[_hands[_turn][index]] = draw_pile;

  // draw a new card if the draw pile is not empty
  if (_draw_pile.back().card == _hands[_turn][index]) {
    _draw_pile.back().multiplicity++;
  } else {
    _draw_pile.push_back({_hands[_turn][index], 1});
  }

  _hands[_turn][index] = card;
  _card_positions[card] = _turn;
  _draw_pile_size++;
}

template <std::size_t num_suits, std::size_t num_players, std::size_t hand_size, uint8_t max_draw_pile_size>
void HanabiState<num_suits, num_players, hand_size, max_draw_pile_size>::revert(const Action &action) {
  decr_turn();
  switch (action.type) {
    case ActionType::clue:
      assert(_num_clues < max_num_clues);
      _num_clues++;
      break;
    case ActionType::discard:
      assert(_num_clues > 0);
      _num_clues--;
      revert_draw(action.index, action.discarded);
      break;
    case ActionType::play:
      if (action.discarded.rank == 0) {
        _num_clues--;
      }
      revert_draw(action.index, action.discarded);
      _stacks[action.discarded.suit]++;
  }
}