wasmex

use rustler::{NifResult, Term};
use wit_parser::{Resolve, WorldItem};

#[rustler::nif(name = "wit_exported_functions")]
pub fn exported_functions(env: rustler::Env, path: String, wit: String) -> NifResult<Term> {
    let mut resolve = Resolve::new();
    let id = resolve
        .push_str(path, &wit)
        .map_err(|e| rustler::Error::Term(Box::new(format!("Failed to parse WIT: {}", e))))?;
    let world_id = resolve
        .select_world(id, None)
        .map_err(|e| rustler::Error::Term(Box::new(format!("Failed to select world: {}", e))))?;
    let exports = &resolve.worlds[world_id].exports;
    let exported_functions = exports
        .iter()
        .filter_map(|(_key, value)| match value {
            WorldItem::Function(function) => Some((&function.name, function.params.len())),
            _ => None,
        })
        .collect::<Vec<(&String, usize)>>();
    Ok(Term::map_from_pairs(env, exported_functions.as_slice()).unwrap())
}