cosmic-applets/cosmic-applet-workspaces/src/wayland_subscription.rs
2025-10-04 02:51:18 +02:00

84 lines
2.4 KiB
Rust

// Copyright 2023 System76 <info@system76.com>
// SPDX-License-Identifier: GPL-3.0-only
use crate::wayland::{self, WorkspaceEvent};
use cctk::{sctk::reexports::calloop::channel::SyncSender, workspace::Workspace};
use cosmic::iced::{
self, Subscription,
futures::{SinkExt, StreamExt, channel::mpsc},
stream,
};
use std::sync::LazyLock;
use tokio::sync::Mutex;
pub static WAYLAND_RX: LazyLock<Mutex<Option<mpsc::Receiver<Vec<Workspace>>>>> =
LazyLock::new(|| Mutex::new(None));
#[derive(Debug, Clone)]
pub enum WorkspacesUpdate {
Workspaces(Vec<Workspace>),
Started(SyncSender<WorkspaceEvent>),
Errored,
}
pub fn workspaces() -> iced::Subscription<WorkspacesUpdate> {
Subscription::run_with_id(
std::any::TypeId::of::<WorkspacesUpdate>(),
stream::channel(50, move |mut output| async move {
let mut state = State::Waiting;
loop {
state = start_listening(state, &mut output).await;
}
}),
)
}
async fn start_listening(
state: State,
output: &mut futures::channel::mpsc::Sender<WorkspacesUpdate>,
) -> State {
match state {
State::Waiting => {
let mut guard = WAYLAND_RX.lock().await;
let rx = {
if guard.is_none() {
if let Ok(WorkspacesWatcher { rx, tx }) = WorkspacesWatcher::new() {
*guard = Some(rx);
_ = output.send(WorkspacesUpdate::Started(tx)).await;
} else {
_ = output.send(WorkspacesUpdate::Errored).await;
return State::Error;
}
}
guard.as_mut().unwrap()
};
if let Some(w) = rx.next().await {
_ = output.send(WorkspacesUpdate::Workspaces(w)).await;
State::Waiting
} else {
_ = output.send(WorkspacesUpdate::Errored).await;
State::Error
}
}
State::Error => cosmic::iced::futures::future::pending().await,
}
}
pub enum State {
Waiting,
Error,
}
pub struct WorkspacesWatcher {
rx: mpsc::Receiver<Vec<Workspace>>,
tx: SyncSender<WorkspaceEvent>,
}
impl WorkspacesWatcher {
pub fn new() -> anyhow::Result<Self> {
let (tx, rx) = mpsc::channel(20);
let tx = wayland::spawn_workspaces(tx);
Ok(Self { rx, tx })
}
}