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use square::*;
use std::ops::{BitAnd, BitOr, BitXor, BitAndAssign, BitOrAssign, BitXorAssign, Mul, Not};
use std::fmt;
use std::sync::{Once, ONCE_INIT};
#[derive(PartialEq, PartialOrd, Clone, Copy)]
pub struct BitBoard(u64);
static SETUP: Once = ONCE_INIT;
pub const EMPTY: BitBoard = BitBoard(0);
impl BitAnd for BitBoard {
type Output = BitBoard;
fn bitand(self, other: BitBoard) -> BitBoard {
BitBoard(self.0 & other.0)
}
}
impl BitOr for BitBoard {
type Output = BitBoard;
fn bitor(self, other: BitBoard) -> BitBoard {
BitBoard(self.0 | other.0)
}
}
impl BitXor for BitBoard {
type Output = BitBoard;
fn bitxor(self, other: BitBoard) -> BitBoard {
BitBoard(self.0 ^ other.0)
}
}
impl BitAndAssign for BitBoard {
fn bitand_assign(&mut self, other: BitBoard) {
self.0 &= other.0;
}
}
impl BitOrAssign for BitBoard {
fn bitor_assign(&mut self, other: BitBoard) {
self.0 |= other.0;
}
}
impl BitXorAssign for BitBoard {
fn bitxor_assign(&mut self, other: BitBoard) {
self.0 ^= other.0;
}
}
impl Mul for BitBoard {
type Output = BitBoard;
fn mul(self, other: BitBoard) -> BitBoard {
BitBoard(self.0.wrapping_mul(other.0))
}
}
impl Not for BitBoard {
type Output = BitBoard;
fn not(self) -> BitBoard {
BitBoard(!self.0)
}
}
impl fmt::Display for BitBoard {
fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
let mut s: String = "".to_owned();
for x in 0..64 {
if self.0 & (1u64 << x) == (1u64 << x) {
s.push_str("X ");
} else {
s.push_str(". ");
}
if x % 8 == 7 {
s.push_str("\n");
}
}
write!(f, "{}", s)
}
}
impl BitBoard {
pub fn new(b: u64) -> BitBoard {
BitBoard(b)
}
pub fn set(rank: u8, file: u8) -> BitBoard {
BitBoard::from_square(Square::make_square(rank, file))
}
pub fn from_square(sq: Square) -> BitBoard {
BitBoard(1u64 << sq.to_int())
}
pub fn from_maybe_square(sq: Option<Square>) -> Option<BitBoard> {
sq.map(|s| BitBoard::from_square(s))
}
pub fn to_square(&self) -> Square {
Square::new(self.0.trailing_zeros() as u8)
}
pub fn popcnt(&self) -> u32 {
self.0.count_ones()
}
pub fn reverse_colors(&self) -> BitBoard {
BitBoard(self.0.swap_bytes())
}
pub fn to_size(&self, rightshift: u8) -> usize {
(self.0 >> rightshift) as usize
}
pub fn get_rank(f: u8) -> BitBoard {
unsafe {
*RANKS.get_unchecked(f as usize)
}
}
pub fn get_file(f: u8) -> BitBoard {
unsafe {
*FILES.get_unchecked(f as usize)
}
}
pub fn get_adjacent_files(f: u8) -> BitBoard {
unsafe {
*ADJACENT_FILES.get_unchecked(f as usize)
}
}
pub fn construct() {
SETUP.call_once(|| {
unsafe {
EDGES = ALL_SQUARES.iter()
.filter(|x| x.rank() == 0 || x.rank() == 7 || x.file() == 0 || x.file() == 7)
.fold(EMPTY, |v, s| v | BitBoard::from_square(*s));
for i in 0..8 {
RANKS[i as usize] = ALL_SQUARES.iter()
.filter(|x| x.rank() == i)
.fold(EMPTY, |v, s| v | BitBoard::from_square(*s));
FILES[i as usize] = ALL_SQUARES.iter()
.filter(|x| x.file() == i)
.fold(EMPTY, |v, s| v | BitBoard::from_square(*s));
ADJACENT_FILES[i as usize] = ALL_SQUARES.iter()
.filter(|y| (y.file() as i8) == (i as i8) - 1 ||
(y.file() as i8) == (i as i8) + 1)
.fold(EMPTY, |v, s| v | BitBoard::from_square(*s));
}
}
});
}
}
static mut EDGES: BitBoard = EMPTY;
static mut RANKS: [BitBoard; 8] = [EMPTY; 8];
static mut FILES: [BitBoard; 8] = [EMPTY; 8];
static mut ADJACENT_FILES: [BitBoard; 8] = [EMPTY; 8];
impl Iterator for BitBoard {
type Item = Square;
fn next(&mut self) -> Option<Square> {
if self.0 == 0 {
None
} else {
let result = self.to_square();
*self ^= BitBoard::from_square(result);
Some(result)
}
}
}