use anyhow::{anyhow, Result};
use std::env;

mod days;

fn help() {
    println!(
        "Usage: {} day-number <day-number>...",
        env!("CARGO_BIN_NAME")
    );
}

fn run_day(number: i32) -> Result<()> {
    match number {
        1 => {
            days::day1::run()?;
        }
        2 => {
            days::day2::run()?;
        }
        3 => {
            days::day3::run()?;
        }
        4 => {
            days::day4::run()?;
        }
        5 => {
            days::day5::run()?;
        }
        6 => {
            days::day6::run()?;
        }
        7 => {
            days::day7::run()?;
        }
        8 => {
            days::day8::run()?;
        }
        9 => {
            days::day9::run()?;
        }
        10 => {
            days::day10::run()?;
        }
        11 => {
            days::day11::run()?;
        }
        12 => {
            days::day12::run()?;
        }
        13 => {
            days::day13::run()?;
        }
        14 => {
            days::day14::run()?;
        }
        15 => {
            days::day15::run()?;
        }
        _ => return Err(anyhow!("Invalid day provided")),
    }
    Ok(())
}

fn main() -> Result<()> {
    let args: Vec<String> = env::args().collect();

    match args.len() {
        0 => {
            help();
            return Err(anyhow!("No arguments provided"));
        }
        1 => {
            help();
            return Err(anyhow!("Not enough arguments provided"));
        }
        _ => {
            for val in args[1..].iter() {
                let number: i32 = match val.parse() {
                    Ok(n) => n,
                    Err(_) => {
                        help();
                        return Err(anyhow!("Argument {} is not an integer", val));
                    }
                };
                println!("Day {}", number);
                run_day(number)?;
                println!();
            }
        }
    }

    Ok(())
}