#include "unittest.h"
#include "board.h"
#include "bitboard.h"

int main() {
  testSection("Bitboards"); {
    unitTest(popCount(0b01110) == 3, "Pop count of 01110 is 3");

    Bitboard bb = 0b1100;
    unitTest(bitscanAndReset(&bb) == 2, "Bitscan of 0b1100 is 2");
    unitTest(bb == 0b1000, "After bitscan with reset the LS1B is flipped");
  }

  testSection("Default FEN string"); {
    Board board = parseFEN("rnbqkbnr/pppppppp/8/8/8/8/PPPPPPPP/RNBQKBNR w KQkq - 0 1");
    unitTest(popCount(board.pieces[PAWN] | board.pieces[PAWN | BLACK]) == 16, "There are 16 pawns total");
    unitTest(popCount(board.pieces[ROOK]) == 2, "There are 2 white rooks");
    // TODO
    unitTest(board.side == WHITE, "Side to move is white");
    unitTest(board.castlingRights == 0, "Both sides can castle");
    unitTest(board.enPassantSquare == 0, "No en passant move is avaialble");
  }

  testSection("Knight attack table"); {
    Bitboard attacks[64];
    precomputeKnightAttackTable(attacks);

    int maxAttacks = 0;
    for (int i = 0; i < 64; i++) {
      int attackCount = popCount(attacks[i]);
      if (attackCount > maxAttacks) maxAttacks = attackCount;
    }
    unitTest(maxAttacks == 8, "Max amount of knight attacks should be 8");

    unitTest(
        attacks[b7] == ((BIT << d8) | (BIT << d6) | (BIT << c5) | (BIT << a5)),
        "Knight on b7 attacks only d8, d6, c5, a5"
    );
  }

  testSection("King attack table"); {
    Bitboard attacks[64];
    precomputeKingAttackTable(attacks);

    int maxAttacks = 0;
    for (int i = 0; i < 64; i++) {
      int attackCount = popCount(attacks[i]);
      if (attackCount > maxAttacks) maxAttacks = attackCount;
    }
    unitTest(maxAttacks == 8, "Max amount of king attacks should be 8");

    unitTest(
        attacks[h2] == ((BIT << h1) | (BIT << g1) | (BIT << g2) | (BIT << g3) | (BIT << h3)),
        "King on h2 attacks only h1, g1, g2, g3, h3"
    );
  }

  testSection("Pawn attack table"); {
    Bitboard whiteAttacks[64];
    Bitboard blackAttacks[64];

    precomputePawnAttackTable(whiteAttacks, WHITE);
    precomputePawnAttackTable(blackAttacks, BLACK);

    int isSame = 0;
    int maxAttacks = 0;
    for (int i = 0; i < 64; i++) {
      int attackCount = popCount(whiteAttacks[i]);
      if (attackCount > maxAttacks) maxAttacks = attackCount;
      if (whiteAttacks[i] == blackAttacks[i]) isSame = 1;
    }
    unitTest(maxAttacks == 2, "Max amount of pawn attacks should be 2");
    unitTest(isSame == 0, "Black and white pawns always move differently");
    unitTest(whiteAttacks[g2] == (BIT << h3 | BIT << f3), "White pawn on g2 attacks only h3 and f3");
  }

  testSection("Attacks to square in starting position"); {
    precomputeKnightAttackTable(KNIGHT_ATTACKS);
    precomputePawnAttackTable(WHITE_PAWN_ATTACKS, WHITE);
    precomputePawnAttackTable(BLACK_PAWN_ATTACKS, BLACK);
    Board board = parseFEN("rnbqkbnr/pppppppp/8/8/8/8/PPPPPPPP/RNBQKBNR w KQkq - 0 1");

    unitTest(attacksToSquare(board, c3) == ((BIT << b1) | (BIT << b2) | (BIT << d2)), "c3 is protected only by b1, b2, d2");
    unitTest(attacksToSquare(board, f6) == ((BIT << g8) | (BIT << g7) | (BIT << e7)), "f6 is protected only by g8, g7, e7");
    // TODO
    unitTest(attacksToSquare(board, d2) == ((BIT << b1) | (BIT << c1) | (BIT << d1) | (BIT << e1)), "d2 is protected only b1, c1, d1, e1");
  }

  report();
  return 0;
}