#![no_std]
#![no_main]
#![feature(type_alias_impl_trait)]

use core::fmt::Write;

use cortex_m_rt::entry;
use defmt::*;
use embassy_executor::Executor;
use embassy_stm32::dma::NoDma;
use embassy_stm32::usart::{Config, Uart};
use embassy_stm32::{bind_interrupts, peripherals, usart};
use heapless::String;
use static_cell::StaticCell;
use {defmt_rtt as _, panic_probe as _};

bind_interrupts!(struct Irqs {
    UART7 => usart::InterruptHandler<peripherals::UART7>;
});

#[embassy_executor::task]
async fn main_task() {
    let p = embassy_stm32::init(Default::default());

    let config = Config::default();
    let mut usart = Uart::new(p.UART7, p.PF6, p.PF7, Irqs, p.DMA1_CH0, NoDma, config);

    for n in 0u32.. {
        let mut s: String<128> = String::new();
        core::write!(&mut s, "Hello DMA World {}!\r\n", n).unwrap();

        usart.write(s.as_bytes()).await.ok();

        info!("wrote DMA");
    }
}

static EXECUTOR: StaticCell<Executor> = StaticCell::new();

#[entry]
fn main() -> ! {
    info!("Hello World!");

    let executor = EXECUTOR.init(Executor::new());

    executor.run(|spawner| {
        unwrap!(spawner.spawn(main_task()));
    })
}