// Embassy async loop.
// Show timers, tasks, and printing together.
// This is why a framework can beat a hand-written loop.

#![allow(unsafe_code)]
#![no_std]
#![no_main]

use cortex_m_semihosting::hprintln;
use embassy_executor::Spawner;
use embassy_time::{Duration, Ticker, Timer};
use panic_probe as _;

// Stub out interrupts that the PAC expects but this chapter does not use.
#[allow(non_snake_case)]
#[unsafe(no_mangle)]
pub extern "C" fn USB_HP_CAN1_TX() {}

// Stub out interrupts that the PAC expects but this chapter does not use.
#[allow(non_snake_case)]
#[unsafe(no_mangle)]
pub extern "C" fn USB_LP_CAN1_RX0() {}

// Stub out interrupts that the PAC expects but this chapter does not use.
#[allow(non_snake_case)]
#[unsafe(no_mangle)]
pub extern "C" fn CAN1_RX1() {}

// Stub out interrupts that the PAC expects but this chapter does not use.
#[allow(non_snake_case)]
#[unsafe(no_mangle)]
pub extern "C" fn CAN1_SCE() {}

// Stub out interrupts that the PAC expects but this chapter does not use.
#[allow(non_snake_case)]
#[unsafe(no_mangle)]
pub extern "C" fn RTC_ALARM() {}

// Stub out interrupts that the PAC expects but this chapter does not use.
#[allow(non_snake_case)]
#[unsafe(no_mangle)]
pub extern "C" fn USBWAKEUP() {}

#[embassy_executor::task]
async fn heartbeat() {
    let mut ticker = Ticker::every(Duration::from_secs(1));

    loop {
        ticker.next().await;
        hprintln!("embassy heartbeat");
    }
}

#[embassy_executor::main]
async fn main(spawner: Spawner) {
    let _p = embassy_stm32::init(Default::default());

    hprintln!("embassy boot");
    spawner.spawn(heartbeat()).unwrap();

    loop {
        Timer::after_secs(2).await;
        hprintln!("embassy main loop");
    }
}