bridge_observation.h

//
// Created by qzz on 2023/9/20.
//

#ifndef BRIDGE_LEARNING_BRIDGE_LIB_BRIDGE_OBSERVATION_H_
#define BRIDGE_LEARNING_BRIDGE_LIB_BRIDGE_OBSERVATION_H_
#include "bridge_game.h"
#include "bridge_hand.h"
#include "bridge_state.h"

namespace bridge_learning_env {
int PlayerToOffset(Player pid, Player observer_pid);

// In bridge, a player can observe
// (1) His hand.
// (2) Auction history
// (3) Contract
// (4) Play history
// (5) Vulnerability
class BridgeObservation {
  public:
    BridgeObservation(const BridgeState& state, Player observing_player);

    BridgeObservation(const BridgeState& state)
      : BridgeObservation(state, state.CurrentPlayer()) {
    }

    Player ObservingPlayer() const { return observing_player_; }

    // offset of current player from observing player.
    int CurPlayerOffset() const { return cur_player_offset_; }

    std::string ToString() const;

    std::array<Trick, kNumTricks> Tricks() const { return tricks_; }

    const std::vector<BridgeHistoryItem>& AuctionHistory() const { return auction_history_; }

    const std::vector<BridgeHistoryItem>& PlayHistory() const { return play_history_; }

    const std::vector<BridgeHistoryItem>& DealHistory() const { return deal_history_; }

    const std::vector<BridgeHand>& Hands() const { return hands_; }

    const std::shared_ptr<BridgeGame>& ParentGame() const { return parent_game_; }

    const std::vector<BridgeMove>& LegalMoves() const { return legal_moves_; }

    bool IsPlayerVulnerable() const { return is_player_vulnerable_; }

    bool IsOpponentVulnerable() const { return is_opponent_vulnerable_; }

    Phase CurrentPhase() const { return current_phase_; }

    Contract GetContract() const { return contract_; }

    int NumCardsPlayed() const { return static_cast<int>(play_history_.size()); }

    int NumDeclarerTricks() const { return num_declarer_tricks_; }

    Player Dummy() const { return Partner(contract_.declarer); }

  private:
    int cur_player_offset_; // offset of current_player_ from observing_player
    Player observing_player_;
    Phase current_phase_;
    // hands_[0] contains observing player's hand.
    std::vector<BridgeHand> hands_;
    std::vector<BridgeMove> legal_moves_;
    std::vector<BridgeHistoryItem> deal_history_;
    std::vector<BridgeHistoryItem> auction_history_;
    std::vector<BridgeHistoryItem> play_history_;
    const Contract contract_;
    bool is_player_vulnerable_;
    bool is_opponent_vulnerable_;
    std::array<Trick, kNumTricks> tricks_;
    int num_declarer_tricks_;
    std::shared_ptr<BridgeGame> parent_game_ = nullptr;
};
} // namespace bridge

#endif // BRIDGE_LEARNING_BRIDGE_LIB_BRIDGE_OBSERVATION_H_