#ifndef SRC_BOARD_H_
#define SRC_BOARD_H_

#include <cstdint>
#include <unordered_map>
#include <vector>

enum PieceType : std::uint8_t {
  NONEPIECE,
  PAWN,
  KNIGHT,
  BISHOP,
  ROOK,
  QUEEN,
  KING,
};

enum GameState : std::uint8_t {
  TURN,
  WHITE_WON,
  BLACK_WON,
  DRAW,
};

struct Piece {
  bool color = false;
  PieceType type = NONEPIECE;
};

struct Position {
  int rank = 0;
  int file = 0;

  bool operator==(const Position &) const = default;
};

/*
 * things here is a diagram for it uint16_t: XXFFFFFFTTTTTT00, XX for promotion
 * flag F for from position T for to position, and 00 for empty ones.
 */

uint16_t CreateMove(uint8_t from, uint8_t to, PieceType promotion = NONEPIECE);
PieceType getPromotionTypeFromMove(uint16_t move);
uint8_t getFromValueFromMove(uint16_t move);
uint8_t getToValueFromMove(uint16_t move);

enum Flag : std::uint8_t { EXACT, LOWERBOUND, UPPERBOUND };

struct TranspositionsEntry {
  int depth = -1;
  int Eval = 0;
  Flag flag = EXACT;
  uint16_t bestMove = {};
};
struct Game {
  Piece pieces[64];
  uint64_t PieceBitboard = 0; // used for quicly iterating over all squares
  uint64_t WhitePieceBitboard = 0;
  uint64_t BlackPieceBitboard = 0;
  uint64_t PieceBitboards[2][7] = {};
  bool turn = true; // 1 white; 0 black
  bool whiteCastleKing = false;
  bool whiteCastleQueen = false;
  bool blackCastleKing = false;
  bool blackCastleQueen = false;
  int halfMoveClock = 0;
  int MoveClock = 0;
  Position enPassant;
  bool canEnpassant = false;
  GameState state = TURN;
  uint64_t hash = 0;
  std::vector<uint64_t> history;
  std::unordered_map<uint64_t, TranspositionsEntry> *Transpositions = nullptr;
};

bool isRepetionDraw(uint64_t key, Game *g);

struct Undo {
  Piece movedPiece;
  Piece capturedPiece;

  uint8_t from;
  uint8_t to;

  bool wasEnPassantCapture = false;
  Position enPassantCapturedSquare;
  Piece enPassantCapturedPiece;

  bool oldTurn;
  bool oldCanEnpassant;
  Position oldEnPassant;

  bool OldWhiteCastleKing;
  bool OldWhiteCastleQueen;
  bool OldBlackCastleKing;
  bool OldBlackCastleQueen;

  int oldHalfMoveClock;
  int oldMoveClock;
  uint64_t ZobristKey;
  GameState oldState;

  // castling
  bool wasCastle = false;
  bool CastledSide = false; // 0 for queen side, 1 for king side
};

int PositionToIndex(Position i);
Undo MakeMove(uint16_t move, Game *g);
void UndoMove(Undo undo, Game *g);

Position FindKing(const Game &g, bool color);
#endif /* SRC_BOARD_H_ */