use std::collections::VecDeque;
use aoc_runner_derive::{aoc, aoc_generator};
#[aoc_generator(day10)]
fn parse(input: &str) -> Vec<char> {
    input.chars().collect()
}

#[aoc(day10, part1)]
fn part1(input: &Vec<char>) -> usize {
    solve(input, 40).len()
}

fn solve(input: &Vec<char>, runs: usize) -> String {
    let mut saying: VecDeque<char> = input.iter().map(|c| *c).collect();
    let mut next: VecDeque<char> = VecDeque::new();
    for _ in 0..runs {
        while let Some(current) = saying.pop_front() {
            let mut count = 1;
            while saying.front() == Some(&current) {
                count += 1;
                saying.pop_front();
            }
            let s = format!("{count}{current}");
            for c in s.chars() {
                next.push_back(c);
            }
        }
        saying = next;
        next = VecDeque::new();
    }
    saying.into_iter().collect()
}

#[aoc(day10, part2)]
fn part2(input: &[char]) -> String {
    todo!()
}


#[cfg(test)]
mod tests {
    use super::*;

    #[test]
    fn part1_example() {
        assert_eq!(solve(&parse("111221"), 1), "312211");
    }

    // #[test]
    // fn part2_example() {
    //     assert_eq!(part2(&parse("<EXAMPLE>")), "<RESULT>");
    // }
}