use proc_macro::TokenStream;
use quote::quote;
use syn::{ItemStruct, parse_macro_input};

#[proc_macro_attribute]
pub fn log_id(_attr: TokenStream, item: TokenStream) -> TokenStream {
    let input = parse_macro_input!(item as ItemStruct);

    let struct_name = &input.ident;
    let generics = &input.generics;

    // This is the important part
    let (impl_generics, type_generics, where_clause) = generics.split_for_impl();

    let struct_name_str = struct_name.to_string();

    let expanded = quote! {
        #input

        impl #impl_generics #struct_name #type_generics #where_clause {
            #[allow(unused)]
            pub const ID: &'static str = #struct_name_str;
        }
    };

    TokenStream::from(expanded)
}