// list of jobs: job (cmd, args) OR rust fn OR python func + cron-like timing
// job runner (thread)
// every job runs in other thread/process
/*

enum Schedule {
    Persistent, // run forever, restart if stops (set max_retries)
    Cron(CronSchedule),
    Once
}
*/

use crate::{
    models::*,
    UResult,
};

use std::collections::HashMap;
use std::pin::Pin;
use std::thread::sleep;
use std::time::{Duration, Instant};
use tokio::process::Command;

use futures::{lock::Mutex, prelude::*};
use lazy_static::lazy_static;
use tokio::{prelude::*, spawn, task::JoinHandle};
use uuid::Uuid;

pub type FutRes = String;
type BoxFut<O> = Pin<Box<dyn Future<Output = O> + Send + 'static>>;

lazy_static! {
    static ref FUT_RESULTS: Mutex<HashMap<Uuid, JoinHandle<FutRes>>> = Mutex::new(HashMap::new());
}

pub async fn apply_tasks(tasks: Vec<impl Future<Output=FutRes> + Send + 'static>) -> Vec<Uuid> {
    let mut fids = Vec::<Uuid>::new();
    for f in tasks.into_iter() {
        let fid = Uuid::new_v4();
        fids.push(fid);
        let result = spawn(Box::pin(f));
        FUT_RESULTS.lock().await.insert(fid, result);
    }
    fids
}

pub async fn apply_task(task: impl Future<Output=FutRes> + Send + 'static) -> Uuid {
    apply_tasks(vec![Box::pin(task)]).await[0]
}

pub async fn pop(fid: Uuid) -> Option<JoinHandle<FutRes>> {
    FUT_RESULTS.lock().await.remove(&fid)
}