use boa_engine::{Context, JsResult, JsString, JsValue, NativeFunction, Source};
use std::str::FromStr;

fn main() -> JsResult<()> {
    let js_code = r#"
      let two = 1 + 1;
      let definitely_not_four = two + "2";

      println(definitely_not_four);

      println(0.1 + 0.2);

      println(Date.now(), 1, new Date()+'');
  "#;

    // Instantiate the execution context
    let mut context = Context::default();

    let println =
        |_this: &JsValue, args: &[JsValue], _context: &mut Context| -> JsResult<JsValue> {
            let mut vals = vec![];
            args.iter()
                .for_each(|arg| vals.push(arg.display().to_string()));
            println!("{}", vals.join(" "));
            Ok(JsValue::undefined())
        };

    _ = context.register_global_callable(
        JsString::from_str("println").unwrap(),
        0,
        NativeFunction::from_copy_closure(println),
    );

    // Parse the source code
    let result = context.eval(Source::from_bytes(js_code))?;

    if !result.is_undefined() {
        println!("{}", result.display());
    }

    Ok(())
}