//! This shows example usage of the CRC functions in ROM

#![no_std]
#![no_main]

use core::fmt::Write;

use esp32c2_hal::{
    clock::ClockControl,
    peripherals::Peripherals,
    prelude::*,
    rom::crc,
    timer::TimerGroup,
    Rtc,
    Uart,
};
use esp_backtrace as _;
use nb::block;

#[entry]
fn main() -> ! {
    let peripherals = Peripherals::take();
    let mut system = peripherals.SYSTEM.split();
    let clocks = ClockControl::boot_defaults(system.clock_control).freeze();

    let mut rtc = Rtc::new(peripherals.RTC_CNTL);
    let mut serial0 = Uart::new(peripherals.UART0, &mut system.peripheral_clock_control);
    let timer_group0 = TimerGroup::new(
        peripherals.TIMG0,
        &clocks,
        &mut system.peripheral_clock_control,
    );
    let mut timer0 = timer_group0.timer0;
    let mut wdt0 = timer_group0.wdt;

    // Disable watchdog timers
    rtc.swd.disable();
    rtc.rwdt.disable();
    wdt0.disable();

    timer0.start(1u64.secs());

    let data = "123456789";

    writeln!(
        serial0,
        "Performing CRC calculations on test string \"{data}\""
    )
    .unwrap();

    loop {
        let crc_hdlc = crc::crc32_le(!0xffffffff, data.as_ref());
        let crc_bzip2 = crc::crc32_be(!0xffffffff, data.as_ref());
        let crc_mpeg2 = !crc::crc32_be(!0xffffffff, data.as_ref());
        let crc_cksum = crc::crc32_be(!0, data.as_ref());
        let crc_kermit = !crc::crc16_le(!0, data.as_ref());
        let crc_genibus = crc::crc16_be(!0xffff, data.as_ref());
        let crc_rohc = !crc::crc8_le(!0xff, data.as_ref());
        let crc_smbus = !crc::crc8_be(!0, data.as_ref());

        assert_eq!(crc_hdlc, 0xcbf43926);
        assert_eq!(crc_bzip2, 0xfc891918);
        assert_eq!(crc_mpeg2, 0x0376e6e7);
        assert_eq!(crc_cksum, 0x765e7680);
        assert_eq!(crc_kermit, 0x2189);
        assert_eq!(crc_genibus, 0xd64e);
        assert_eq!(crc_rohc, 0xd0);
        assert_eq!(crc_smbus, 0xf4);

        writeln!(
            serial0,
            "{:08x} {:08x} {:08x} {:08x} {:04x} {:04x} {:02x} {:02x}",
            crc_hdlc, crc_bzip2, crc_mpeg2, crc_cksum, crc_kermit, crc_genibus, crc_rohc, crc_smbus
        )
        .unwrap();

        block!(timer0.wait()).unwrap();
    }
}