use crate::{
    board::{board::Color, mailbox::Mailbox},
    movegen::r#move::Move,
};

use super::MAX_HISTORY;

// ttmove: -100, mvvlva: [-32, 5], killer:6, quiet[7, ..]
pub fn score_move(
    mailbox: &Mailbox,
    mv: Move,
    killer_move: Option<Move>,
    color: Color,
    history_heuristic: Option<&[[[i32; 64]; 64]; 2]>,
    tt_move: Option<Move>,
) -> i32 {
    if Some(mv) == tt_move {
        return -100;
    }

    if mv.is_capture() {
        let aggressor = mailbox.piece_at(mv.src()).unwrap();
        if let Some(victim) = mailbox.piece_at(mv.dst()) {
            return aggressor.0.idx() as i32 - 8 * victim.0.idx() as i32;
        }
        return 0; //en passant
    }

    if Some(mv) == killer_move {
        return 6;
    }

    history_heuristic.map_or(MAX_HISTORY + 6 + 1, |hh| {
        -hh[color][mv.src()][mv.dst()] + MAX_HISTORY + 6 + 1
    })
}

#[cfg(test)]
mod tests {
    use crate::{
        board::{fen::from_fen, square::Square},
        movegen::r#move::{Move, MoveType},
    };

    use super::score_move;

    const FEN: &'static str = "1r2k2r/2P1p2p/2npb1q1/1p3ppP/p3P3/P2B1Q2/1P1PNPP1/R3K2R w KQk - 0 1";

    #[test]
    fn test_score_move() -> Result<(), String> {
        let game = from_fen(FEN)?;
        let queen_takes_pawn = Move::new_with_type(Square::F3, Square::F5, MoveType::Capture);
        let pawn_takes_queen = Move::new_with_type(Square::H5, Square::G6, MoveType::Capture);
        let castle = Move::new_with_type(Square::E1, Square::C1, MoveType::QueenCastle);

        let mut moves = vec![castle, queen_takes_pawn, pawn_takes_queen];
        moves.sort_unstable_by_key(|mv| {
            score_move(&game.mailbox, *mv, None, game.current_player(), None, None)
        });

        assert_eq!(moves, vec![pawn_takes_queen, queen_takes_pawn, castle]);

        moves.sort_unstable_by_key(|mv| {
            score_move(
                &game.mailbox,
                *mv,
                None,
                game.current_player(),
                None,
                Some(castle),
            )
        });

        assert_eq!(moves, vec![castle, pawn_takes_queen, queen_takes_pawn]);

        Ok(())
    }
}