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//! # Day 8: Two-Factor Authentication
//!
//! You come across a door implementing what you can only assume is an implementation of
//! [two-factor authentication] after a long game of [requirements] [telephone].
//!
//! To get past the door, you first swipe a keycard (no problem; there was one on a nearby desk).
//! Then, it displays a code on a [little screen], and you type that code on a keypad. Then,
//! presumably, the door unlocks.
//!
//! Unfortunately, the screen has been smashed. After a few minutes, you've taken everything apart
//! and figured out how it works. Now you just have to work out what the screen **would** have
//! displayed.
//!
//! The magnetic strip on the card you swiped encodes a series of instructions for the screen; these
//! instructions are your puzzle input. The screen is **`50` pixels wide and `6` pixels tall**, all
//! of which start **off**, and is capable of three somewhat peculiar operations:
//!
//! - `rect AxB` turns **on** all of the pixels in a rectangle at the top-left of the screen which
//!   is `A` wide and `B` tall.
//! - `rotate row y=A by B` shifts all of the pixels in row `A` (0 is the top row) **right** by `B`
//!   pixels. Pixels that would fall off the right end appear at the left end of the row.
//! - `rotate column x=A by B` shifts all of the pixels in column `A` (0 is the left column)
//!   **down** by `B` pixels. Pixels that would fall off the bottom appear at the top of the column.
//!
//! For example, here is a simple sequence on a smaller screen:
//!
//! - `rect 3x2` creates a small rectangle in the top-left corner:
//!
//! ```txt
//! ###....
//! ###....
//! .......
//! ```
//!
//! - `rotate column x=1 by 1` rotates the second column down by one pixel:
//!
//! ```txt
//! #.#....
//! ###....
//! .#.....
//! ```
//!
//! - `rotate row y=0 by 4` rotates the top row right by four pixels:
//!
//! ```txt
//! ....#.#
//! ###....
//! .#.....
//! ```
//!
//! - `rotate column x=1 by 1` again rotates the second column down by one pixel, causing the bottom
//!   pixel to wrap back to the top:
//!
//! ```txt
//! .#..#.#
//! #.#....
//! .#.....
//! ```
//!
//! As you can see, this display technology is extremely powerful, and will soon dominate the
//! tiny-code-displaying-screen market. That's what the advertisement on the back of the display
//! tries to convince you, anyway.
//!
//! There seems to be an intermediate check of the voltage used by the display: after you swipe your
//! card, if the screen did work, **how many pixels should be lit?**
//!
//! [two-factor authentication]: https://en.wikipedia.org/wiki/Multi-factor_authentication
//! [requirements]: https://en.wikipedia.org/wiki/Requirement
//! [telephone]: https://en.wikipedia.org/wiki/Chinese_whispers
//! [little screen]: https://www.google.com/search?q=tiny+lcd&tbm=isch

use anyhow::Result;

pub const INPUT: &str = include_str!("d08.txt");

pub fn solve_part_one(input: &str) -> Result<i64> {
    Ok(0)
}

pub fn solve_part_two(input: &str) -> Result<i64> {
    Ok(0)
}

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

    #[test]
    fn part_one() {}

    #[test]
    fn part_two() {}
}