#[macro_use]
extern crate neon;
extern crate num_cpus;
extern crate rand;

use neon::prelude::*;

// tom pridham @ jane
fn hello(mut cx: FunctionContext) -> JsResult<JsString> {
    Ok(cx.string("hello node"))
}

fn thread_count(mut cx: FunctionContext) -> JsResult<JsNumber> {
    Ok(cx.number(num_cpus::get() as f64))
}

fn noop(mut cx: FunctionContext) -> JsResult<JsUndefined> {
    Ok(cx.undefined())
}

fn throw_panic(mut _cx: FunctionContext) -> JsResult<JsError> {
    panic!("this is just a test");
    //Ok(cx.error("this is just a test"));
}

fn throw_err(mut cx: FunctionContext) -> JsResult<JsError> {
    cx.error("this is just a test")
}

fn greet(mut cx: FunctionContext) -> JsResult<JsString> {
    //cx.check_argument::<JsString>(0)?;
    let str = cx.argument::<JsString>(0)?.value();
    Ok(cx.string(str))
}

fn any(mut cx: FunctionContext) -> JsResult<JsValue> {
    use rand::prelude::*;

    //let mut rng = rand::thread_rng();
    //let i = rng.gen::<u32>() % 5;
    let mut rng = rand::rngs::OsRng::new().unwrap();
    let i = rng.next_u32() % 5;
    let val: Handle<JsValue> = match i {
        0 => cx.string("foobar").upcast(),
        1 => cx.number(42).upcast(),
        2 => cx.boolean(true).upcast(),
        3 => cx.empty_array().upcast(),
        4 => cx.null().upcast(),
        _ => cx.undefined().upcast(),
    };
    //cx.check_argument::<JsString>(0)?;
    //let str = cx.argument::<JsString>(0)?.value();
    Ok(val)
}

register_module!(mut cx, {
    cx.export_function("hello", hello)?;
    cx.export_function("threadCount", thread_count)?;
    cx.export_function("throw", throw_err)?;
    cx.export_function("panic", throw_panic)?;
    cx.export_function("greet", greet)?;
    cx.export_function("noop", noop)?;
    cx.export_function("any", any)?;
    Ok(())
});