#![no_main]
#![no_std]

use cortex_m_rt::entry;
use embedded_hal::digital::InputPin;
use microbit::{Board, display::blocking::Display, hal::Timer};
use panic_halt as _;

const NEUTRAL: [[u8; 5]; 5] = [
    [0, 0, 0, 0, 0],
    [0, 0, 0, 0, 0],
    [0, 0, 1, 0, 0],
    [0, 0, 0, 0, 0],
    [0, 0, 0, 0, 0],
];

const RIGHT: [[u8; 5]; 5] = [
    [0, 0, 1, 0, 0],
    [0, 1, 0, 0, 0],
    [1, 1, 1, 1, 1],
    [0, 1, 0, 0, 0],
    [0, 0, 1, 0, 0],
];

const LEFT: [[u8; 5]; 5] = [
    [0, 0, 1, 0, 0],
    [0, 0, 0, 1, 0],
    [1, 1, 1, 1, 1],
    [0, 0, 0, 1, 0],
    [0, 0, 1, 0, 0],
];

#[entry]
fn main() -> ! {
    let board = Board::take().unwrap();
    let mut timer = Timer::new(board.TIMER0);
    let mut display = Display::new(board.display_pins);

    let mut button_a = board.buttons.button_a;
    let mut button_b = board.buttons.button_b;

    loop {
        display.clear();
        let a_pressed = button_a.is_low().unwrap();
        let b_pressed = button_b.is_low().unwrap();

        let display_out = match (a_pressed, b_pressed) {
            (false, false) | (true, true) => NEUTRAL,
            (true, false) => RIGHT,
            (false, true) => LEFT,
        };

        display.show(&mut timer, display_out, 10);
    }
}