use sub_core::fnv1;

#[inline(always)]
pub unsafe fn find_import_hashed(module_name: u64, func_name: u64) -> Option<usize> {
    crate::modules::loaded_modules()
        .filter( |&(_,slice)|fnv1::hash_utf16(slice) == module_name).next()
        .and_then(|(i,_)|i.exports())
        .and_then(|v|{
            v.filter_map(|(p,n)|(fnv1::hash_utf8(n) == func_name).then_some(p)).next()
        })
}



pub macro lazy_import ( $module:literal $($v:vis fn $name:ident($($pname:ident: $ptype:ty),*) $(-> $rtype:ty)?; )* ) {
    $(
        #[allow(unused, non_snake_case)] #[inline(always)]
        $v fn $name($($pname: $ptype),*) $(-> $rtype)? {
            type FTYPE = extern "C" fn($($pname: $ptype),*) $(-> $rtype)?;
            static mut FUNC: Option<FTYPE> = None;
            let function = match unsafe { FUNC } {
                Some(function) => function,
                None => unsafe {
                    let import = core::mem::transmute(find_import_hashed(
                        const { fnv1::hash_utf8($module.as_bytes()) },
                        const { fnv1::hash_utf8(stringify!($name).as_bytes()) }
                    ).unwrap_or(0));
                    FUNC = Some(import);
                    import
                }
            };
            function($($pname),*)
        }
    )*
}