use super::{race_record::RaceRecord, NumericValue};

pub fn parsing(input: &str) -> Vec<RaceRecord> {
    let mut must_be_2_lines = input.lines().take(2);
    match (must_be_2_lines.next(), must_be_2_lines.next()) {
        (Some(first_line), Some(second_line)) => {
            let stripped_first = first_line.strip_prefix("Time:").unwrap();
            let stripped_second = second_line.strip_prefix("Distance:").unwrap();
            let splitted_first = stripped_first
                .split_whitespace()
                .map(|to_parse| to_parse.parse::<NumericValue>().unwrap());
            let splitted_second = stripped_second
                .split_whitespace()
                .map(|to_parse| to_parse.parse::<NumericValue>().unwrap());
            splitted_first
                .zip(splitted_second)
                .map(|(time, distance)| RaceRecord::new(time, distance))
                .collect()
        }
        _ => unreachable!(),
    }
}

pub fn parsing_part_2(input: &str) -> RaceRecord {
    let (time_str, reached_str) = parsing(input)
        .into_iter()
        .map(|record| {
            (
                record.time().to_string(),
                record.reached_distance().to_string(),
            )
        })
        .fold(
            (String::new(), String::new()),
            |(acc_time_str, acc_reached_str), (time_str, distance_str)| {
                (acc_time_str + &time_str, acc_reached_str + &distance_str)
            },
        );
    RaceRecord::new(time_str.parse().unwrap(), reached_str.parse().unwrap())
}

#[cfg(test)]
mod testing {
    use crate::solutions::day6::race_record::RaceRecord;

    #[test]
    fn should_parse() {
        let input = include_str!("day_example_input.txt");
        let parsed = super::parsing(input);

        let expected = vec![
            RaceRecord::new(7, 9),
            RaceRecord::new(15, 40),
            RaceRecord::new(30, 200),
        ];
        assert_eq!(expected, parsed);
    }

    #[test]
    fn should_parse_part_2() {
        let input = include_str!("day_example_input.txt");
        let parsed = super::parsing_part_2(input);

        let expected = RaceRecord::new(71530, 940200);
        assert_eq!(expected, parsed);
    }
}