use aoc_runner_derive::{aoc, aoc_generator};

use itertools::Itertools;

#[aoc_generator(day1)]
pub fn parse_measurements(input: &str) -> Vec<usize> {
    input
        .split('\n')
        .map(|input| input.parse().unwrap())
        .collect()
}

#[aoc(day1, part1)]
pub fn count_increases_indexed(input: &[usize]) -> usize {
    let mut count = 0;
    for i in 1..input.len() {
        if input[i - 1] < input[i] {
            count += 1;
        }
    }
    count
}

#[aoc(day1, part1, tuple_windows)]
pub fn count_increases_tuple_windows(input: &[usize]) -> usize {
    let mut count = 0;
    for (a, b) in input.iter().tuple_windows() {
        if a < b {
            count += 1;
        }
    }
    count
}

#[aoc(day1, part1, slice_windows)]
pub fn count_increases_slice_windows(input: &[usize]) -> usize {
    let mut count = 0;
    for window in input.windows(2) {
        if window[0] < window[1] {
            count += 1;
        }
    }
    count
}

#[aoc(day1, part2)]
pub fn count_sliding_increases_indexed(input: &[usize]) -> usize {
    let mut count = 0;
    for i in 3..input.len() {
        if input[i - 3] + input[i - 2] + input[i - 1] < input[i - 2] + input[i - 1] + input[i] {
            count += 1;
        }
    }
    count
}

#[aoc(day1, part2, tuple_windows)]
pub fn count_sliding_increases_tuple_windows(input: &[usize]) -> usize {
    let mut count = 0;
    for (a, b, c, d) in input.iter().tuple_windows() {
        if a + b + c < b + c + d {
            count += 1;
        }
    }
    count
}

#[aoc(day1, part2, slice_windows)]
pub fn count_sliding_increases_slice_windows(input: &[usize]) -> usize {
    let mut count = 0;
    for w in input.windows(4) {
        if w[0] + w[1] + w[2] < w[1] + w[2] + w[3] {
            count += 1;
        }
    }
    count
}