use crate::{board::Board, square::Square};

pub enum BoardState {
    Finished,
    Broken(u8),
    InProgress,
}

fn are_unique<T>(iter: T) -> bool
where
    T: Iterator<Item = u8>,
{
    let mut bitmap: bitmaps::Bitmap<10> = bitmaps::Bitmap::new();

    for item in iter {
        if bitmap.get(item as usize) {
            return false;
        }
        bitmap.set(item as usize, true);
    }
    true
}

pub fn validate_board(board: &Board) -> BoardState {
    for r in 0..9 {
        if !are_unique(board.row(r).filter_map(|sq| match sq {
            Square::Value(x) => Some(x),
            _ => None,
        })) {
            // TODO: Add the index.
            return BoardState::Broken(0);
        }
    }

    for c in 0..9 {
        if !are_unique(board.col(c).filter_map(|sq| match sq {
            Square::Value(x) => Some(x),
            _ => None,
        })) {
            // TODO: Add the index.
            return BoardState::Broken(0);
        }
    }

    for b in 0..9 {
        if !are_unique(board.boxn(b).filter_map(|sq| match sq {
            Square::Value(x) => Some(x),
            _ => None,
        })) {
            // TODO: Add the index.
            return BoardState::Broken(0);
        }
    }

    if board.squares.iter().any(|sq| match sq {
        Square::Marks(_) => true,
        _ => false,
    }) {
        BoardState::InProgress
    } else {
        BoardState::Finished
    }
}