use std::str;
use typst_wasm_protocol::wasm_export;

#[wasm_export]
fn fend_evaluate(query: &[u8]) -> Result<String, String> {
    let input = str::from_utf8(query).map_err(|e| format!("UTF-8 error: {}", e))?;
    let mut ctx = fend_core::Context::new();
    let mut result = String::new();
    match fend_core::evaluate(input, &mut ctx) {
        Ok(res) => {
            if !res.output_is_empty() {
                result.push_str(res.get_main_result());
            }
        }
        Err(msg) => {
            return Err(format!("Error: {msg}"));
        }
    }
    Ok(result.to_string())
}