#include "BitBoard.h"

BitBoard::BitBoard(uint64_t v) {
    mBoard = v;
}

std::ostream &operator<<(std::ostream &os, const BitBoard &board) {
    // For debugging only, performance isn't important
    for (int i = 7; i >= 0; i--) {
        int rank = i * 8;
        for (int j = 0; j < 8; j++) {
            // Get the piece for this index. Assume it exists.
            // Print piece, otherwise '.';
            if (board.mBoard & (1ULL << (rank + j))) {
                os << 1;
            } else {
                os << '.';
            }

            os << ' ';
        }
        os << '\n';
    }

    return os;
}

BitBoard BitBoard::getRank(int r) {
    return (genShift(1ULL, (r + 1) * 8) - 1) & genShift(~1ULL, r * 8 - 1);
}
BitBoard BitBoard::genShift(BitBoard x, const int s) {
    return (s < 0) ? (x >> -s) : (s > 63) ? x : (x << s);
}

BitBoard BitBoard::northFill() const {
    BitBoard result(mBoard);
    result |= (result << 8);
    result |= (result << 16);
    result |= (result << 32);
    return (result << 8);
}

BitBoard BitBoard::southFill() const {
    BitBoard result(mBoard);
    result |= (result >> 8);
    result |= (result >> 16);
    result |= (result >> 32);
    return result;
}

BitBoard BitBoard::fileFill() const {
    return northFill() | southFill();
}