rfs-runner 0.1.4

use colored::Colorize;
use tokio::select;
use tokio::sync::mpsc::Receiver;

use crate::error::Error;
use crate::templates::WorkerTemplate;
use crate::{limit_string, wsupdate, wsupdate_async, MainProgress, Result, Uid, WorkerState, WorkerStatus};

pub struct WorkerHandle<D, F, Fut, S>
where
  Fut: Future<Output = anyhow::Result<()>> + Send + 'static,
  Fut::Output: Send + 'static,
  F: Fn(D, MainProgress<S>) -> Fut,
{
  fn_ptr: F,
  receiver: Receiver<D>,
  main_ui: MainProgress<S>,
  worker_state: WorkerState<S>,
}

impl<D, F, Fut, S: WorkerTemplate> WorkerHandle<D, F, Fut, S>
where
  D: Send,
  Fut: Future<Output = anyhow::Result<()>> + Send + 'static,
  Fut::Output: Send + 'static,
  F: Fn(D, MainProgress<S>) -> Fut,
{
  fn initialize(mut self) -> Self {
    self.main_ui.add_worker(self.worker_state.id, &self.worker_state);

    wsupdate! {
      self.worker_state,
      self.receiver,
      "New worker spawned",
      WorkerStatus::Spawned,
    }

    self.worker_state.set_status(WorkerStatus::Waiting);
    self
  }

  pub async fn run(mut self) {
    use WorkerStatus::*;

    while let Some(data) = self.receiver.recv().await {
      self.main_ui.inc(1);

      wsupdate! {
        self.worker_state,
        self.receiver,
        "Processing...",
        Running
      }

      let call = &mut self.fn_ptr;
      select! {
        _ = wsupdate_async!(self.worker_state, self.receiver,) => (),
        result = call(data, self.main_ui.clone()) => self.update_state(result)
      }
    }

    self.worker_state.set_jobs(self.receiver.len());
    self.worker_state.set_status(Stopped);
    self.worker_state.set_task("All finished!");
  }

  fn update_state(&mut self, output: anyhow::Result<()>) {
    if let Err(error) = output {
      let (task, status) = if self.receiver.is_empty() {
        ("Waiting", WorkerStatus::Waiting)
      } else {
        ("Processing", WorkerStatus::Running)
      };

      wsupdate! {
        &mut self.worker_state,
        self.receiver,
        "Waiting Jobs",
        status
      }

      self.worker_state.set_jobs(self.receiver.len());
      self.worker_state.set_task(task);

      let error = limit_string(116, error, None).bright_red();
      self.main_ui.set_message(error.to_string());
    }
  }
}

pub struct WorkerHandleBuilder<D, F, Fut, S: WorkerTemplate>
where
  D: Send,
  Fut: Future<Output = anyhow::Result<()>> + Send + 'static,
  Fut::Output: Send + 'static,
  F: Fn(D, MainProgress<S>) -> Fut,
{
  fn_ptr: Option<F>,
  main_ui: Option<MainProgress<S>>,
  receiver: Option<Receiver<D>>,
}

impl<D, F, Fut, S: WorkerTemplate> Default for WorkerHandleBuilder<D, F, Fut, S>
where
  D: Send,
  Fut: Future<Output = anyhow::Result<()>> + Send + 'static,
  Fut::Output: Send + 'static,
  F: Fn(D, MainProgress<S>) -> Fut,
{
  fn default() -> Self {
    Self {
      fn_ptr: None,
      main_ui: None,
      receiver: None,
    }
  }
}

impl<D, F, Fut, S: WorkerTemplate> WorkerHandleBuilder<D, F, Fut, S>
where
  D: Send,
  Fut: Future<Output = anyhow::Result<()>> + Send + 'static,
  Fut::Output: Send + 'static,
  F: Fn(D, MainProgress<S>) -> Fut,
{
  pub fn fn_ptr(mut self, f: F) -> Self {
    self.fn_ptr = Some(f);
    self
  }

  pub fn main_ui(mut self, ui: MainProgress<S>) -> Self {
    self.main_ui = Some(ui);
    self
  }

  pub fn receiver(mut self, receiver: Receiver<D>) -> Self {
    self.receiver = Some(receiver);
    self
  }

  pub fn build(self, uid: Uid) -> Result<WorkerHandle<D, F, Fut, S>> {
    let fn_ptr = self.fn_ptr.ok_or(Error::Missing("[`WorkerHandleBuilder`] missing [`FnMut`]"))?;
    let receiver = self.receiver.ok_or(Error::Missing("[`WorkerHandleBuilder`] missing [`Receiver<T>`]"))?;
    let main_ui = self.main_ui.ok_or(Error::Missing("[`WorkerHandleBuilder`] missing [`MainProgress`]"))?;
    let worker_state = WorkerState::new(uid, main_ui.clone());

    let handle = WorkerHandle {
      fn_ptr,
      receiver,
      main_ui,
      worker_state,
    };

    Ok(handle.initialize())
  }
}

#[cfg(test)]
mod test {
  use std::num::NonZero;
  use std::sync::atomic::AtomicBool;
  use std::sync::Arc;

  use indicatif::MultiProgress;
  use tokio::spawn;

  use super::*;
  use crate::DefaultTemplate;

  #[tokio::test]
  async fn test_build() {
    let style = DefaultTemplate::new("Test");
    let (_, rx) = tokio::sync::mpsc::channel::<String>(1);
    let main_ui = MainProgress::new(10, MultiProgress::new(), style);

    let handle = WorkerHandleBuilder::default()
      .fn_ptr(async |_: String, _: MainProgress<DefaultTemplate>| Ok(()))
      .main_ui(main_ui)
      .receiver(rx)
      .build(NonZero::new(1).unwrap());

    assert!(handle.is_ok());

    let handle = handle.unwrap();
    let join_handle = spawn(handle.run());
    join_handle.abort();
  }

  #[tokio::test]
  async fn test_capture_owned_var() {
    async fn the_solver_fn(_: String, _: MainProgress<DefaultTemplate>, _: Arc<AtomicBool>) -> anyhow::Result<()> {
      Ok(())
    }

    let (_, rx) = tokio::sync::mpsc::channel::<String>(1);
    let main_ui = MainProgress::new(10, MultiProgress::new(), DefaultTemplate::new("Test"));
    let moveable = Arc::new(AtomicBool::default());

    let ref_4_fn_ptr_owned = moveable.clone();

    let handle = WorkerHandleBuilder::default()
      .fn_ptr(move |msg: String, ui: MainProgress<DefaultTemplate>| the_solver_fn(msg, ui, ref_4_fn_ptr_owned.clone()))
      .main_ui(main_ui)
      .receiver(rx)
      .build(NonZero::new(1).unwrap());

    assert!(handle.is_ok());

    let handle = handle.unwrap();
    let join_handle = spawn(handle.run());
    join_handle.abort();
  }
}