#include "board.hpp"
#include <cctype>
#include <cstdio>
#include <iostream>
#include <print>
#include <string>

bool WHITE = true;
bool BLACK = false;

const char toChar(pieceType type) {
  switch (type) {
  case NONE:
    return '.';
  case PAWN:
    return 'P';
  case KNIGHT:
    return 'N';
  case BISHOP:
    return 'B';
  case ROOK:
    return 'R';
  case QUEEN:
    return 'Q';
  case KING:
    return 'K';
  default:
    return '?';
  }
}

Piece createPiece(pieceType type, bool color, bool moved) {
  Piece piece;
  piece.type = type;
  piece.color = color;
  piece.moved = moved;
  return piece;
};
void printBoard(board *b) {
  std::string line = "  +-----------------+\n";
  std::string letter = "    a b c d e f g h\n";

  std::cout << letter;
  std::cout << line;

  for (int rank = 0; rank < 8; rank++) {
    std::printf("%d |", 8 - rank);
    for (int file = 0; file < 8; file++) {
      Piece piece = b->pieces[rank * 8 + file];
      char symbol = toChar(piece.type);
      if (piece.color == BLACK) {
        symbol = std::tolower(static_cast<unsigned char>(symbol));
      }
      std::printf(" %c", symbol);
    }
    std::printf(" | %d\n", 8 - rank);
  }

  std::cout << line;
  std::cout << letter;
  
  std::println();
  std::println("Turn: {}", b->turn == WHITE ? "White" : "Black");
  std::println("Castling: {}", b->castle);
}

void setBoardFen(std::string fen, board *b) {
  // example fen rnbqkbnr/pppppppp/8/8/8/8/PPPPPPPP/RNBQKBNR w KQkq - 0 1
  int file = 0;
  int rank = 0;

  std::string castle = "";

  enum parserState {
    POSITION,
    TURN,
    CASTLE,
    ENPASSANT,
    CLOCK1,
    CLOCK2,
  };
  parserState state = POSITION;

  for (int i = 0; i < fen.length(); i++) {
    std::printf("state: %d\n", state);
    std::printf("doing: %c\n", fen[i]);
    if (fen[i] == ' ') {
      if (state == POSITION) {
        state = TURN;
        continue;
      }
      if (state == TURN) {
        state = CASTLE;
        continue;
      }
      if (state == CASTLE) {
        state = ENPASSANT;
        continue;
      }
      continue;
    }
    if (state == CASTLE) {
      if (fen[i] == '-') {
        castle = "-";
        continue;
      }
      if (toupper(fen[i]) == 'K') {
        castle += fen[i];
        continue;
      }
      if (toupper(fen[i]) == 'Q') {
        castle += fen[i];
        continue;
      }
    }
    if (state == TURN) {
      if (toupper(fen[i]) == 'W') {
        b->turn = WHITE;
        continue;
      }
      if (toupper(fen[i]) == 'B') {
        b->turn = BLACK;
        continue;
      }
    }
    if (state == POSITION) {
      if (isdigit(fen[i])) {
        int move = fen[i] - '0';
        file += move;
        if (file > 8) {
          std::println("Fatal: file was to big");
          return; // malformed rank
        }
        continue;
      }
      if (fen[i] == '/') {
        file = 0;
        rank++;
        if (rank > 8) {
          std::println("Fatal: rank was to big");
          return; // malformed rank
        }
        continue;
      }
      if (toupper(fen[i]) == 'N') {
        Piece piece = createPiece(KNIGHT, isupper(fen[i]));
        b->pieces[rank * 8 + file] = piece;
        file++;
        continue;
      }
      if (toupper(fen[i]) == 'R') {
        Piece piece = createPiece(ROOK, isupper(fen[i]));
        b->pieces[rank * 8 + file] = piece;
        file++;
        continue;
      }
      if (toupper(fen[i]) == 'Q') {
        Piece piece = createPiece(QUEEN, isupper(fen[i]));
        b->pieces[rank * 8 + file] = piece;
        file++;
        continue;
      }
      if (toupper(fen[i]) == 'B') {
        Piece piece = createPiece(BISHOP, isupper(fen[i]));
        b->pieces[rank * 8 + file] = piece;
        file++;
        continue;
      }
      if (toupper(fen[i]) == 'P') {
        Piece piece = createPiece(PAWN, isupper(fen[i]));
        b->pieces[rank * 8 + file] = piece;
        file++;
        continue;
      }
      if (toupper(fen[i]) == 'K') {
        Piece piece = createPiece(KING, isupper(fen[i]));
        b->pieces[rank * 8 + file] = piece;
        file++;
        continue;
      }
    }
    break;
  }
  b->castle = castle.empty() ? "-" : castle;
}