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use templates::*;
use std::fmt;
static SRC_MASK: u16 = 0b0000_000000_111111;
static DST_MASK: u16 = 0b0000_111111_000000;
static PR_MASK: u16 = 0b1000_000000_000000;
static CP_MASK: u16 = 0b0100_000000_000000;
static FLAG_MASK: u16 = 0b1111_000000_000000;
static SP_MASK: u16 = 0b0011_000000_000000;
#[derive(Copy, Clone, PartialEq, Eq)]
pub struct BitMove {
data: u16,
}
#[derive(Copy, Clone, PartialEq)]
pub enum MoveFlag {
Promotion { capture: bool, prom: Piece },
Castle { king_side: bool },
DoublePawnPush,
Capture { ep_capture: bool },
QuietMove,
}
#[derive(Copy, Clone, PartialEq, Debug)]
pub enum MoveType {
Promotion,
Castle,
EnPassant,
Normal,
}
#[derive(Copy, Clone, PartialEq)]
pub struct PreMoveInfo {
pub src: SQ,
pub dst: SQ,
pub flags: MoveFlag,
}
impl fmt::Display for BitMove {
fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
write!(f, "{}", self.stringify())
}
}
impl BitMove {
pub fn new(input: u16) -> BitMove {
BitMove { data: input }
}
pub fn init(info: PreMoveInfo) -> BitMove {
let src = info.src as u16;
let dst = (info.dst as u16) << 6;
let flags = info.flags;
let flag_bits: u16 = match flags {
MoveFlag::Promotion { capture, prom } => {
let p_bit: u16 = match prom {
Piece::R => 2,
Piece::B => 1,
Piece::N => 0,
Piece::Q | _ => 3,
};
let cp_bit = if capture { 4 } else { 0 };
p_bit + cp_bit + 8
}
MoveFlag::Capture { ep_capture } => {
if ep_capture {
5
} else {
4
}
}
MoveFlag::Castle { king_side } => {
if king_side {
2
} else {
3
}
}
MoveFlag::DoublePawnPush => 1,
MoveFlag::QuietMove => 0,
};
BitMove { data: (flag_bits << 12) | src | dst }
}
pub fn null() -> Self {
BitMove { data: 0 }
}
pub fn is_null(&self) -> bool {
self.data == 0
}
#[inline(always)]
pub fn is_capture(&self) -> bool {
((self.data & CP_MASK) >> 14) == 1
}
#[inline(always)]
pub fn is_quiet_move(&self) -> bool {
((self.data & FLAG_MASK) >> 12) == 0
}
#[inline(always)]
pub fn is_promo(&self) -> bool {
(self.data & PR_MASK) != 0
}
#[inline(always)]
pub fn get_dest(&self) -> SQ {
((self.data & DST_MASK) >> 6) as u8
}
#[inline(always)]
pub fn get_src(&self) -> SQ {
(self.data & SRC_MASK) as u8
}
#[inline(always)]
pub fn is_castle(&self) -> bool {
((self.data & FLAG_MASK) >> 13) == 1
}
#[inline(always)]
pub fn is_king_castle(&self) -> bool {
((self.data & FLAG_MASK) >> 12) == 2
}
#[inline(always)]
pub fn is_queen_castle(&self) -> bool {
((self.data & FLAG_MASK) >> 12) == 3
}
#[inline(always)]
pub fn is_en_passant(&self) -> bool {
(self.data & FLAG_MASK) >> 12 == 5
}
#[inline(always)]
pub fn is_double_push(&self) -> (bool, u8) {
let is_double_push: u8 = ((self.data & FLAG_MASK) >> 12) as u8;
match is_double_push {
1 => (true, self.get_dest() as u8),
_ => (false, 64),
}
}
#[inline(always)]
pub fn dest_row(&self) -> u8 {
((self.data & DST_MASK) >> 6) as u8 / 8
}
#[inline(always)]
pub fn dest_col(&self) -> u8 {
((self.data & DST_MASK) >> 6) as u8 % 8
}
#[inline(always)]
pub fn src_row(&self) -> u8 {
(self.data & SRC_MASK) as u8 / 8
}
#[inline(always)]
pub fn src_col(&self) -> u8 {
(self.data & SRC_MASK) as u8 % 8
}
#[inline(always)]
pub fn promo_piece(&self) -> Piece {
match (self.data >> 12) & 0b0011 {
0 => Piece::N,
1 => Piece::B,
2 => Piece::R,
3 | _ => Piece::Q,
}
}
#[inline(always)]
pub fn move_type(&self) -> MoveType {
if self.is_castle() {
return MoveType::Castle;
}
if self.is_promo() {
return MoveType::Promotion;
}
if self.is_en_passant() {
return MoveType::EnPassant;
}
MoveType::Normal
}
pub fn stringify(&self) -> String {
let src = parse_sq(self.get_src());
let dst = parse_sq(self.get_dest());
let mut s = format!("{}{}", src, dst);
if self.is_promo() {
let char = match self.promo_piece() {
Piece::B => 'b',
Piece::N => 'n',
Piece::R => 'r',
Piece::Q => 'q',
_ => unreachable!(),
};
s.push(char);
}
s
}
pub fn get_raw(&self) -> u16 {
self.data
}
}