#ifndef DYNAMIC_PROGRAM_GAME_INTERFACE_H
#define DYNAMIC_PROGRAM_GAME_INTERFACE_H

#include <cstddef>
#include <iosfwd>
#include <vector>
#include <memory>

#include "hanabi_types.hpp"


namespace Hanabi
{

  /**
   * A card together with an associated multiplicity
   */
  struct CardMultiplicity
  {
    Card card;
    unsigned multiplicity;

    bool operator==(const CardMultiplicity &) const;
    bool operator!=(const CardMultiplicity &) const;
  };

  struct HanabiStateConfig
  {
    /** What score to consider as a win. If left empty, automatically replaced by max score on construction. */
    std::optional<uint8_t> score_goal;
    /** The number of clues gained when a stack is finished or a card is discarded. Usually 1, 1/2 in clue starved. */
    clue_t num_clues_gained_on_discard_or_stack_finished {1};
    /**
     * If set to true, only roughly half of the game states will be stored in the internal lookup table.
     * This results in roughly halving memory consumption at the cost of roughly a factor 3-5 in execution speed
     * (the slowdown is theoretically bounded to visiting at most 9 times the number of states if this option is activated).
     * You should typically never need this, unless you are very specifically short on memory and.
     * */
    bool save_memory {false};
  };

  class HanabiStateIF
  {
  public:
    virtual void give_clue() = 0;

    virtual void discard(hand_index_t index) = 0;

    virtual void play(hand_index_t index) = 0;

    virtual void rotate_next_draw(const Card & card) = 0;

    [[nodiscard]] virtual ActionType last_action_type() const = 0;

    virtual void revert() = 0;

    virtual void modify_clues(clue_t change) = 0;

    virtual void set_clues(clue_t clues) = 0;

    [[nodiscard]] virtual player_t turn() const = 0;

    [[nodiscard]] virtual clue_t num_clues() const = 0;

    [[nodiscard]] virtual unsigned num_strikes() const = 0;

    [[nodiscard]] virtual unsigned score() const = 0;

    [[nodiscard]] virtual std::vector<std::vector<Card>> hands() const = 0;

    [[nodiscard]] virtual std::vector<Card> cur_hand() const = 0;

    [[nodiscard]] virtual size_t draw_pile_size() const = 0;

    [[nodiscard]] virtual bool is_trash(const Card & card) const = 0;

    /** Returns whether the card is critical, assuming it is not trash already */
    [[nodiscard]] virtual bool is_critical(const Card & card) const = 0;

    [[nodiscard]] virtual bool is_playable(const Card & card) const = 0;

    [[nodiscard]] virtual bool is_relative_state_initialized() const = 0;

    [[nodiscard]] virtual hand_index_t find_card_in_hand(const Card & card) const = 0;

    [[nodiscard]] virtual std::uint64_t enumerated_states() const = 0;

    [[nodiscard]] virtual const map_type<unsigned long, probability_t> & position_tablebase() const = 0;

    virtual void init_backtracking_information() = 0;

    virtual probability_t evaluate_state() = 0;

    [[nodiscard]] virtual std::optional<probability_t> lookup() const = 0;

    [[nodiscard]] virtual std::uint64_t unique_id() const = 0;

    [[nodiscard]] virtual std::pair<std::vector<std::uint64_t>, std::vector<Card>> dump_unique_id_parts() const = 0;

    virtual std::vector<std::pair<Action, std::optional<probability_t>>> get_reasonable_actions(bool evaluate_all = false, bool reasonable = true) = 0;

    virtual std::vector<std::pair<CardMultiplicity, std::optional<probability_t>>>
    possible_next_states(hand_index_t index, bool play) = 0;

    virtual ~HanabiStateIF() = default;

  protected:
    virtual void print(std::ostream & os) const = 0;

    friend std::ostream & operator<<(std::ostream &, HanabiStateIF const &);
  };

  std::ostream & operator<<(std::ostream & os, HanabiStateIF const & hanabi_state);

  struct GameInfo
  {
    std::vector<Hanabi::Card> deck;
    std::vector<Hanabi::Action> actions;
    Hanabi::suit_t num_suits;
    Hanabi::player_t num_players;
    clue_t num_clues_gained_per_discard_or_stack_finished;
  };

  struct Game : private GameInfo
  {
  public:
    Game(std::unique_ptr<HanabiStateIF> state, GameInfo game_info);

    [[nodiscard]] unsigned cur_turn() const;
    [[nodiscard]] unsigned num_turns() const;

    void make_turn();

    void revert_turn();

    bool goto_draw_pile_size(size_t draw_pile_break);

    bool goto_turn(size_t turn);

    [[nodiscard]] bool holds_state() const;

    std::unique_ptr<HanabiStateIF> state;
    unsigned next_action;
  };

}
#endif //DYNAMIC_PROGRAM_GAME_INTERFACE_H