extern crate tokio_core;
extern crate futures;
extern crate rand;

use std::time::Duration;
use std::io;

use tokio_core::reactor::Interval;
use tokio_core::reactor::Handle;
use futures::Stream;
use types::*;

pub struct ParamWaiter {
}

impl ParamWaiter {
    fn step(&mut self) -> Params {
        let mut p = Params::defaults();
        let mut rng = rand::thread_rng();
        p.fridge_setpoint = 17.0 + 4.0*rand::random::<f32>();
        p
    }

    pub fn new() -> Self {
        ParamWaiter {}
    }

    pub fn run(handle: &Handle, rate: u64) -> Box<Stream<Item=Params, Error=io::Error>> {
        let mut s = ParamWaiter::new();

        let dur = Duration::from_millis(rate);
        Interval::new(dur, handle).unwrap().map(move |()| {
            s.step()
        }).boxed()
    }
}