use anyhow::Result;
use std::fs;

pub fn run() -> Result<()> {
    let file_contents = fs::read_to_string("day4.txt")?;
    let lines = file_contents.lines();
    let mut part_one_pairs = 0;
    let mut part_two_pairs = 0;

    for line in lines {
        let v: Vec<&str> = line.split(",").collect();
        let left: Vec<u32> = v[0].split("-").map(|t| t.parse::<u32>().unwrap()).collect();
        let right: Vec<u32> = v[1].split("-").map(|t| t.parse::<u32>().unwrap()).collect();

        let left_outside = left[0] <= right[0] && left[1] >= right[1];
        let left_inside = left[0] >= right[0] && left[1] <= right[1];
        let left_covered = left_outside || left_inside;

        let right_outside = right[0] <= left[0] && right[1] >= left[1];
        let right_inside = right[0] >= left[0] && right[1] <= left[1];
        let right_covered = right_outside || right_inside;

        if left_covered && right_covered {
            part_one_pairs += 1;
        }

        let left_1_inside = left[0] >= right[0] && left[0] <= right[1];
        let left_2_inside = left[1] >= right[0] && left[1] <= right[1];
        let right_1_inside = right[0] >= left[0] && right[0] <= left[1];
        let right_2_inside = right[1] >= left[0] && right[1] <= left[1];
        if left_1_inside || left_2_inside || right_1_inside || right_2_inside {
            part_two_pairs += 1;
        }
    }
    println!("part one pairs {}", part_one_pairs);
    println!("part two pairs {}", part_two_pairs);

    Ok(())
}