From 1074f3f49b8822de1967b3e097a596ff1759f06f Mon Sep 17 00:00:00 2001
From: Ashley Wulber <ashley@system76.com>
Date: Tue, 11 Jul 2023 14:12:18 -0400
Subject: [PATCH] refactor(audio) use channel subscription

---
 cosmic-applet-audio/src/pulse.rs | 97 +++++++++++++++++++-------------
 1 file changed, 58 insertions(+), 39 deletions(-)

diff --git a/cosmic-applet-audio/src/pulse.rs b/cosmic-applet-audio/src/pulse.rs
index a86a501e..7c3c6991 100644
--- a/cosmic-applet-audio/src/pulse.rs
+++ b/cosmic-applet-audio/src/pulse.rs
@@ -2,7 +2,8 @@ use std::cell::RefCell;
 use std::{rc::Rc, thread};
 
 extern crate libpulse_binding as pulse;
-use cosmic::iced::{subscription, Subscription};
+use cosmic::iced::{self, subscription};
+use cosmic::iced_futures::futures::{self, SinkExt};
 //use futures::channel::mpsc;
 use libpulse_binding::{
     callbacks::ListResult,
@@ -16,42 +17,47 @@ use libpulse_binding::{
     volume::ChannelVolumes,
 };
 
-pub fn connect() -> Subscription<Event> {
-    struct Connect;
+pub fn connect() -> iced::Subscription<Event> {
+    struct SomeWorker;
+
+    subscription::channel(
+        std::any::TypeId::of::<SomeWorker>(),
+        50,
+        move |mut output| async move {
+            let mut state = State::Init;
 
-    subscription::unfold(
-        std::any::TypeId::of::<Connect>(),
-        State::Init,
-        |mut state| async move {
             loop {
-                let (update, new_state) = connection(state).await;
-                state = new_state;
-                if let Some(update) = update {
-                    return (update, state);
-                }
+                state = start_listening(state, &mut output).await;
             }
         },
     )
 }
 
-async fn connection(state: State) -> (Option<Event>, State) {
+async fn start_listening(
+    state: State,
+    output: &mut futures::channel::mpsc::Sender<Event>,
+) -> State {
     match state {
         State::Init => {
             let PulseHandle {
                 to_pulse,
                 from_pulse,
             } = PulseHandle::new();
-            (
-                Some(Event::Init(Connection(to_pulse))),
-                State::Connecting(from_pulse),
-            )
+            _ = output.send(Event::Init(Connection(to_pulse))).await;
+
+            State::Connecting(from_pulse)
         }
         // Waiting for Connection to succeed
         // The GUI doesn't have to monitor this state, as it is never sent to the GUI
         State::Connecting(mut from_pulse) => match from_pulse.recv().await {
-            Some(Message::Connected) => (Some(Event::Connected), State::Connected(from_pulse)),
+            Some(Message::Connected) => {
+                _ = output.send(Event::Connected).await;
+                State::Connected(from_pulse)
+            }
             Some(Message::Disconnected) => {
-                (Some(Event::Disconnected), State::Connecting(from_pulse))
+                _ = output.send(Event::Disconnected).await;
+
+                State::Connecting(from_pulse)
             }
             Some(m) => {
                 panic!("Unexpected message: {:?}", m);
@@ -63,27 +69,40 @@ async fn connection(state: State) -> (Option<Event>, State) {
         State::Connected(mut from_pulse) => {
             // This is where we match messages from the pulse server to pass to the gui
             match from_pulse.recv().await {
-                Some(Message::SetSinks(sinks)) => (
-                    Some(Event::MessageReceived(Message::SetSinks(sinks))),
-                    State::Connected(from_pulse),
-                ),
-                Some(Message::SetSources(sources)) => (
-                    Some(Event::MessageReceived(Message::SetSources(sources))),
-                    State::Connected(from_pulse),
-                ),
-                Some(Message::SetDefaultSink(sink)) => (
-                    Some(Event::MessageReceived(Message::SetDefaultSink(sink))),
-                    State::Connected(from_pulse),
-                ),
-                Some(Message::SetDefaultSource(source)) => (
-                    Some(Event::MessageReceived(Message::SetDefaultSource(source))),
-                    State::Connected(from_pulse),
-                ),
-                Some(Message::Disconnected) => {
-                    (Some(Event::Disconnected), State::Connecting(from_pulse))
+                Some(Message::SetSinks(sinks)) => {
+                    _ = output
+                        .send(Event::MessageReceived(Message::SetSinks(sinks)))
+                        .await;
+
+                    State::Connected(from_pulse)
                 }
-                None => (Some(Event::Disconnected), State::Connecting(from_pulse)),
-                _ => (None, State::Connected(from_pulse)),
+                Some(Message::SetSources(sources)) => {
+                    _ = output
+                        .send(Event::MessageReceived(Message::SetSources(sources)))
+                        .await;
+                    State::Connected(from_pulse)
+                }
+                Some(Message::SetDefaultSink(sink)) => {
+                    _ = output
+                        .send(Event::MessageReceived(Message::SetDefaultSink(sink)))
+                        .await;
+                    State::Connected(from_pulse)
+                }
+                Some(Message::SetDefaultSource(source)) => {
+                    _ = output
+                        .send(Event::MessageReceived(Message::SetDefaultSource(source)))
+                        .await;
+                    State::Connected(from_pulse)
+                }
+                Some(Message::Disconnected) => {
+                    _ = output.send(Event::Disconnected).await;
+                    State::Connecting(from_pulse)
+                }
+                None => {
+                    _ = output.send(Event::Disconnected).await;
+                    State::Connecting(from_pulse)
+                }
+                _ => State::Connected(from_pulse),
             }
         }
     }