use crate::path::ModulePrefix;
use darling::FromMeta;
use proc_macro2::TokenStream;
use quote::{format_ident, quote};
use syn::spanned::Spanned;

#[derive(Debug, FromMeta)]
pub enum HfclkSource {
    Internal,
    ExternalXtal,
}

impl Default for HfclkSource {
    fn default() -> Self {
        Self::Internal
    }
}

#[derive(Debug, FromMeta)]
pub enum LfclkSource {
    InternalRC,
    Synthesized,
    ExternalXtal,
    ExternalLowSwing,
    ExternalFullSwing,
}

impl Default for LfclkSource {
    fn default() -> Self {
        Self::InternalRC
    }
}

#[derive(Debug, FromMeta, Default)]
pub struct Args {
    #[darling(default)]
    pub embassy_prefix: ModulePrefix,
    #[darling(default)]
    pub hfclk_source: HfclkSource,
    #[darling(default)]
    pub lfclk_source: LfclkSource,
}

pub fn generate(args: &Args) -> TokenStream {
    let hfclk_source = format_ident!("{}", format!("{:?}", args.hfclk_source));
    let lfclk_source = format_ident!("{}", format!("{:?}", args.lfclk_source));

    let embassy_path = args.embassy_prefix.append("embassy").path();
    let embassy_nrf_path = args.embassy_prefix.append("embassy_nrf").path();

    quote!(
        use #embassy_nrf_path::{interrupt, peripherals, rtc};

        let mut config = #embassy_nrf_path::system::Config::default();
        config.hfclk_source = #embassy_nrf_path::system::HfclkSource::#hfclk_source;
        config.lfclk_source = #embassy_nrf_path::system::LfclkSource::#lfclk_source;
        unsafe { #embassy_nrf_path::system::configure(config) };

        let mut rtc = rtc::RTC::new(unsafe { <peripherals::RTC1 as #embassy_path::util::Steal>::steal() }, interrupt::take!(RTC1));
        let rtc = unsafe { make_static(&mut rtc) };
        rtc.start();
        let mut alarm = rtc.alarm0();

        unsafe { #embassy_path::time::set_clock(rtc) };

        let alarm = unsafe { make_static(&mut alarm) };
        executor.set_alarm(alarm);
    )
}