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mod attacks;
mod castle;
mod lookup;
mod pawn;
mod pinned;
pub mod slider;
mod util;
use self::attacks::*;
use self::castle::*;
use self::lookup::*;
use self::pawn::*;
use self::pinned::*;
use self::slider::consts::squares_between;
use self::slider::*;
use self::attacks::king_danger_squares;
use bb::EMPTY;
use mv_list::MoveList;
use piece::KING;
use position::Position;
pub fn legal_moves<L: MoveList>(position: &Position, list: &mut L) -> bool {
let stm = position.state().stm;
let kings = position.bb_pc(KING.pc(stm));
let attacked_squares = king_danger_squares(kings, stm.flip(), position);
let king_sq = kings.bitscan();
let (checkers, pinned, pinners) = checkers_and_pinned(kings, stm.flip(), position);
let king_attacks_count = checkers.pop_count();
let mut capture_mask = !EMPTY;
let mut push_mask = !EMPTY;
if king_attacks_count > 1 {
king_moves(position, !attacked_squares, list);
return true;
} else if king_attacks_count == 1 {
capture_mask = checkers;
push_mask = EMPTY;
let checker_sq = checkers.bitscan();
let checker = position.at(checker_sq);
debug_assert!(checker.is_some());
if checker.is_slider() {
push_mask = squares_between(king_sq, checker_sq)
}
} else {
castles(position, attacked_squares, list);
}
let move_mask = capture_mask | push_mask;
knight_moves(position, move_mask, !pinned, list);
slider_moves(position, move_mask, pinned, king_sq, list);
pawn_moves(position, capture_mask, push_mask, !pinned, list);
pawn_pin_ray_moves(position, king_sq, pinned, pinners, stm, list);
king_moves(position, !attacked_squares, list);
king_attacks_count > 0
}
#[cfg(test)]
mod test {
use super::*;
use mv_list::MoveVec;
use position::STARTING_POSITION_FEN;
macro_rules! test_gen {
($name:ident, $moves:expr, $fen:expr) => {
#[test]
fn $name() {
let mut list = MoveVec::new();
let position = &Position::from_fen($fen).unwrap();
legal_moves::<MoveVec>(position, &mut list);
if list.len() != $moves {
println!("Found {} moves, expected {}", list.len(), $moves);
println!("Moves: {}", list);
println!("{}", position);
}
assert_eq!(list.len(), $moves);
}
};
}
test_gen!(test_starting_position, 20, STARTING_POSITION_FEN);
test_gen!(test_debug_1, 8, "r6r/1b2k1bq/8/8/7B/8/8/R3K2R b QK - 3 2");
test_gen!(test_debug_2, 8, "8/8/8/2k5/2pP4/8/B7/4K3 b - d3 5 3");
test_gen!(
test_debug_3,
19,
"r1bqkbnr/pppppppp/n7/8/8/P7/1PPPPPPP/RNBQKBNR w QqKk - 2 2"
);
test_gen!(
test_debug_4,
5,
"r3k2r/p1pp1pb1/bn2Qnp1/2qPN3/1p2P3/2N5/PPPBBPPP/R3K2R b QqKk - 3 2"
);
test_gen!(
test_debug_5,
44,
"2kr3r/p1ppqpb1/bn2Qnp1/3PN3/1p2P3/2N5/PPPBBPPP/R3K2R b QK - 3 2"
);
test_gen!(
test_debug_6,
39,
"rnb2k1r/pp1Pbppp/2p5/q7/2B5/8/PPPQNnPP/RNB1K2R w QK - 3 9"
);
test_gen!(test_debug_7, 8, "5k2/8/8/q7/8/2Q5/8/4K3 w - -");
test_gen!(test_debug_8, 9, "2r5/3pk3/8/2P5/8/2K5/8/8 w - - 5 4");
}