use louds_rs::{Louds, LoudsNodeNum};

#[test]
fn fuzzing_test() {
    use rand::prelude::*;

    let samples = 100;
    let mut rng = rand::thread_rng();

    fn generate_lbs(rng: &mut ThreadRng) -> String {
        let mut s = String::from("10");
        let (mut cnt0, mut cnt1) = (1u64, 1u64);
        while cnt0 < cnt1 + 1 {
            let r = rng.gen::<f64>();
            if r < 0.6 {
                s = format!("{}{}", s, "0");
                cnt0 += 1;
            } else {
                s = format!("{}{}", s, "1");
                cnt1 += 1;
            }
        }
        s
    }

    for _ in 0..samples {
        let s = generate_lbs(&mut rng);
        eprintln!("build(): LBS = \"{}\"", s);

        let n_nodes = s.len() / 2;
        let louds = Louds::from(s.as_str());

        for raw_node_num in 1..=n_nodes {
            let node_num = LoudsNodeNum(raw_node_num as u64);
            eprintln!("NodeNum({:?})", raw_node_num);

            // index(node_num_to_index(node_num)) == node_num
            let index = louds.node_num_to_index(node_num);
            assert_eq!(louds.index_to_node_num(index), node_num);

            // `node_num`'s children have `node_num` as parent.
            for child_index in louds.parent_to_children(node_num) {
                assert_eq!(louds.child_to_parent(child_index), node_num);
            }
        }
    }
}