use core::fmt::Write;
use core::panic::PanicInfo;
use hal::{
    clock::GenericClockController,
    gpio::{Pa10, Pa11, PfC},
    pac::Peripherals,
    prelude::*,
    sercom::{PadPin, Sercom0Pad2, Sercom0Pad3, UART0},
    time,
};

#[panic_handler]
fn panic(info: &PanicInfo) -> ! {
    let mut peripherals = unsafe { Peripherals::steal() };
    let mut pins = hal::Pins::new(peripherals.PORT);
    let mut red_led = pins.d13.into_open_drain_output(&mut pins.port);
    red_led.set_high().ok();

    let mut clocks = GenericClockController::with_internal_32kosc(
        peripherals.GCLK,
        &mut peripherals.PM,
        &mut peripherals.SYSCTRL,
        &mut peripherals.NVMCTRL,
    );
    let glck0 = clocks.gclk0();

    let mut uart: UART0<Sercom0Pad3<Pa11<PfC>>, Sercom0Pad2<Pa10<PfC>>, (), ()> = UART0::new(
        &clocks.sercom0_core(&glck0).unwrap(),
        time::Hertz(115200),
        peripherals.SERCOM0,
        &mut peripherals.PM,
        (
            pins.d0.into_pad(&mut pins.port),
            pins.d1.into_pad(&mut pins.port),
        ),
    );

    loop {
        uart.write_str("## PANIC ##\r\n").ok();
        if let Some(location) = info.location() {
            writeln!(
                uart,
                "Panic occured in file {}\r\nAt location {}\r\n",
                location.file(),
                location.line(),
            )
            .ok();
        } else {
            uart.write_str("No location info available...\r\n").ok();
        }
    }
}