#![no_std]
#![no_main]

use core::cell::RefCell;

use cortex_m_rt::{entry, exception};
#[cfg(feature = "defmt")]
use defmt_rtt as _;
use embassy_boot_rp::*;
use embassy_sync::blocking_mutex::Mutex;
use embassy_time::Duration;

const FLASH_SIZE: usize = 2 * 1024 * 1024;

#[entry]
fn main() -> ! {
    let p = embassy_rp::init(Default::default());

    // Uncomment this if you are debugging the bootloader with debugger/RTT attached,
    // as it prevents a hard fault when accessing flash 'too early' after boot.
    /*
    for i in 0..10000000 {
        cortex_m::asm::nop();
    }
    */

    let flash = WatchdogFlash::<FLASH_SIZE>::start(p.FLASH, p.WATCHDOG, Duration::from_secs(8));
    let flash = Mutex::new(RefCell::new(flash));

    let config = BootLoaderConfig::from_linkerfile_blocking(&flash);
    let active_offset = config.active.offset();
    let bl: BootLoader = BootLoader::prepare(config);

    unsafe { bl.load(embassy_rp::flash::FLASH_BASE as u32 + active_offset) }
}

#[no_mangle]
#[cfg_attr(target_os = "none", link_section = ".HardFault.user")]
unsafe extern "C" fn HardFault() {
    cortex_m::peripheral::SCB::sys_reset();
}

#[exception]
unsafe fn DefaultHandler(_: i16) -> ! {
    const SCB_ICSR: *const u32 = 0xE000_ED04 as *const u32;
    let irqn = core::ptr::read_volatile(SCB_ICSR) as u8 as i16 - 16;

    panic!("DefaultHandler #{:?}", irqn);
}

#[panic_handler]
fn panic(_info: &core::panic::PanicInfo) -> ! {
    cortex_m::asm::udf();
}