//! Day 1: Trebuchet?!

use aho_corasick::AhoCorasick;

pub const DAY: u8 = 1;
pub const TITLE: &str = "Trebuchet?!";

pub fn part1(input: Vec<String>) -> String {
    input
        .iter()
        .map(|line| {
            let numbers = line
                .chars()
                .filter(char::is_ascii_digit)
                .collect::<Vec<_>>();
            let (first, last) = (numbers.first().unwrap(), numbers.last().unwrap());
            first.to_digit(10).unwrap() * 10 + last.to_digit(10).unwrap()
        })
        .sum::<u32>()
        .to_string()
}

pub fn part2(input: Vec<String>) -> String {
    let ac = AhoCorasick::new([
        "0", "1", "2", "3", "4", "5", "6", "7", "8", "9", "one", "two", "three", "four", "five",
        "six", "seven", "eight", "nine",
    ])
    .unwrap();

    input
        .iter()
        .map(|line| {
            let mut numbers = ac.find_overlapping_iter(line).map(|m| {
                let p = m.pattern().as_u32();
                if p < 10 {
                    p
                } else {
                    p - 9
                }
            });
            let first = numbers.next().expect(line);
            let last = numbers.last().unwrap_or(first);
            first * 10 + last
        })
        .sum::<u32>()
        .to_string()
}

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

    #[test]
    fn t_example1() {
        assert_eq!(part1(crate::read_example(DAY, 1)), "142");
    }

    #[test]
    fn t_part1() {
        assert_eq!(part1(crate::read_input(DAY)), "56049");
    }

    #[test]
    fn t_example2() {
        assert_eq!(part2(crate::read_example(DAY, 2)), "281");
    }

    #[test]
    fn t_part2() {
        assert_eq!(part2(crate::read_input(DAY)), "54530");
    }
}