Be able to add tracks, start, stop, and pause playback from the web api

Cargo.lock

@@ -1946,11 +1946,13 @@ dependencies = [
 name = "gm-dash"
 version = "0.1.0"
 dependencies = [
+ "cool_asserts",
  "glib 0.18.5",
  "gstreamer",
  "pipewire",
  "serde 1.0.209",
  "serde_json",
+ "thiserror",
  "tokio",
  "warp",
 ]

gm-dash/server/Cargo.toml

@@ -13,3 +13,6 @@ serde_json  = { version = "1.0.127" }
 tokio       = { version = "1.39.3", features = ["full"] }
 warp        = { version = "0.3.7" }
 glib        = { version = "0.18" }
+thiserror = "1.0.63"
+cool_asserts = "2.0.3"
+

gm-dash/server/src/app.rs

@@ -1,97 +0,0 @@
-use crate::audio_control::AudioControl;
-use std::{
-    collections::HashSet,
-    sync::{Arc, RwLock},
-};
-
-struct AppState {
-    device_list: Vec<String>,
-    track_list: Vec<String>,
-    currently_playing: HashSet<String>,
-
-    audio_control: AudioControl,
-}
-
-impl Default for AppState {
-    fn default() -> Self {
-        Self {
-            device_list: vec![],
-            track_list: vec![
-                "/home/savanni/Music/Travis Savoie/RPG Toolkit Volume II/01 - A Day to Rebuild.mp3.mp3".to_owned(),
-                "/home/savanni/Music/Travis Savoie/RPG Toolkit Volume II/02 - Against the Clock.mp3.mp3".to_owned(),
-                "/home/savanni/Music/Travis Savoie/RPG Toolkit Volume II/03 - Alleyway Cutthroat.mp3.mp3".to_owned(),
-                "/home/savanni/Music/Travis Savoie/RPG Toolkit Volume II/04 - Beasts Of Legend.mp3.mp3".to_owned(),
-                "/home/savanni/Music/Travis Savoie/RPG Toolkit Volume II/05 - Books and Spellcrafting.mp3.mp3".to_owned(),
-            ],
-            currently_playing: HashSet::default(),
-
-            audio_control: AudioControl::default(),
-        }
-    }
-}
-
-#[derive(Clone)]
-pub struct App {
-    internal: Arc<RwLock<AppState>>,
-}
-
-impl App {
-    fn new() -> App {
-        let internal = AppState::default();
-        App {
-            internal: Arc::new(RwLock::new(internal)),
-        }
-    }
-
-    pub fn add_audio(&self, device: String) {
-        let mut st = self.internal.write().unwrap();
-        st.device_list.push(device);
-    }
-
-    pub fn audio_devices(&self) -> Vec<String> {
-        let st = self.internal.read().unwrap();
-        st.device_list.clone()
-    }
-
-    pub fn tracks(&self) -> Vec<String> {
-        let st = self.internal.read().unwrap();
-        st.track_list.clone()
-    }
-
-    pub fn play_pause(&self) -> Result<(), String> {
-        self.internal.write().unwrap().audio_control.play_pause();
-        Ok(())
-    }
-
-    pub fn add_track(&self, track: String) -> Result<(), String> {
-        let mut st = self.internal.write().unwrap();
-        if st.track_list.contains(&track) {
-            st.currently_playing.insert(track.clone());
-        }
-        st.audio_control.add_track(track);
-        Ok(())
-    }
-
-    pub fn stop(&self, track: String) -> Result<(), String> {
-        let mut st = self.internal.write().unwrap();
-        st.currently_playing.remove(&track);
-        Ok(())
-    }
-
-    pub fn stop_all(&self) -> Result<(), String> {
-        let mut st = self.internal.write().unwrap();
-        st.currently_playing = HashSet::new();
-        Ok(())
-    }
-
-    pub fn playing(&self) -> Vec<String> {
-        let st = self.internal.read().unwrap();
-        st.currently_playing.iter().cloned().collect()
-    }
-}
-
-impl Default for App {
-    fn default() -> App {
-        App::new()
-    }
-}

gm-dash/server/src/app/mod.rs

@@ -0,0 +1,163 @@
+use std::{
+    collections::HashMap,
+    path::PathBuf,
+    sync::{Arc, RwLock},
+};
+
+use tokio::{
+    sync::mpsc::{Receiver, Sender},
+    task::JoinHandle,
+};
+
+use crate::{
+    audio_control::AudioControl,
+    types::{
+        AppError, AudioControlMessage, AudioState, AudioStatusMessage, TrackInfo, TrackSpec, Volume,
+    },
+};
+
+#[cfg(test)]
+mod tests;
+
+struct AppState {
+    playing: bool,
+
+    device_list: Vec<String>,
+    track_list: Vec<PathBuf>,
+
+    track_status: Vec<TrackInfo>,
+}
+
+impl Default for AppState {
+    fn default() -> Self {
+        Self {
+            playing: false,
+
+            device_list: vec![],
+            track_list: vec![],
+
+            track_status: vec![],
+        }
+    }
+}
+
+pub struct App {
+    state: Arc<RwLock<AppState>>,
+
+    audio_control: Sender<AudioControlMessage>,
+
+    listener: JoinHandle<()>,
+}
+
+impl App {
+    pub fn new(
+        audio_control: Sender<AudioControlMessage>,
+        mut audio_status: Receiver<AudioStatusMessage>,
+    ) -> App {
+        let state = Arc::new(RwLock::new(AppState::default()));
+
+        let listener = tokio::spawn({
+            let state = state.clone();
+            async move {
+                println!("listener started");
+                while let Some(msg) = audio_status.recv().await {
+                    match msg {
+                        AudioStatusMessage::Playing => {
+                            state.write().unwrap().playing = true;
+                        }
+                        AudioStatusMessage::Status(AudioState {
+                            playing: _playing,
+                            tracks,
+                        }) => {
+                            state.write().unwrap().track_status = tracks;
+                        }
+                        msg => println!("message received from audio controller: {:?}", msg),
+                    }
+                }
+                println!("listener exiting");
+            }
+        });
+
+        Self {
+            state,
+            audio_control,
+            listener,
+        }
+    }
+
+    pub fn playing(&self) -> bool {
+        self.state.read().unwrap().playing
+    }
+
+    pub fn add_audio(&self, device: String) {
+        /*
+        let mut st = self.internal.write().unwrap();
+        st.device_list.push(device);
+        */
+    }
+
+    pub fn audio_devices(&self) -> Vec<String> {
+        /*
+        let st = self.internal.read().unwrap();
+        st.device_list.clone()
+        */
+        vec![]
+    }
+
+    pub fn enabled_tracks(&self) -> Vec<PathBuf> {
+        let st = self.state.read().unwrap();
+        st.track_status.iter().map(|ti| ti.path.clone()).collect()
+    }
+
+    pub async fn enable_track(&self, path: PathBuf) -> Result<(), AppError> {
+        println!("enabling track: {}", path.display());
+        self.audio_control
+            .send(AudioControlMessage::EnableTrack(TrackSpec {
+                path,
+                volume: Volume::try_from(1.0).unwrap(),
+            }))
+            .await
+            .expect("audio control send to succeed");
+        /*
+        let st = self.internal.write().unwrap();
+        st.audio_control.add_track(TrackSpec{ path })?;
+        */
+
+        Ok(())
+    }
+
+    pub async fn disable_track(&self, _track: &str) -> Result<(), AppError> {
+        /*
+        let mut st = self.internal.write().unwrap();
+        if st.currently_playing.contains_key(track) {
+            st.currently_playing.remove(track);
+        }
+        Ok(())
+        */
+        Ok(())
+    }
+
+    pub async fn play(&self) -> Result<(), AppError> {
+        self.audio_control
+            .send(AudioControlMessage::Play)
+            .await
+            .expect("audio control send to succeed");
+        Ok(())
+    }
+
+    pub async fn stop(&self) -> Result<(), AppError> {
+        self.audio_control
+            .send(AudioControlMessage::Stop)
+            .await
+            .expect("audio control send to succeed");
+        Ok(())
+    }
+
+    pub async fn pause(&self) -> Result<(), AppError> {
+        self.audio_control
+            .send(AudioControlMessage::Pause)
+            .await
+            .expect("audio control send to succeed");
+        Ok(())
+    }
+}

gm-dash/server/src/app/tests.rs

@@ -0,0 +1,126 @@
+use std::{future::Future, path::PathBuf, time::Duration};
+
+use cool_asserts::assert_matches;
+use tokio::sync::mpsc::{Receiver, Sender};
+
+use crate::{
+    app::{App, AppError},
+    types::{AudioControlMessage, AudioStatusMessage, Progress, TrackInfo, TrackSpec, Volume},
+};
+
+fn memory_app() -> (
+    App,
+    Receiver<AudioControlMessage>,
+    Sender<AudioStatusMessage>,
+) {
+    let (audio_control_tx, audio_control_rx) = tokio::sync::mpsc::channel(5);
+    let (audio_status_tx, audio_status_rx) = tokio::sync::mpsc::channel(5);
+    let app = App::new(audio_control_tx, audio_status_rx);
+
+    (app, audio_control_rx, audio_status_tx)
+}
+
+#[tokio::test]
+async fn app_starts_in_stopped_state() {
+    let (app, _control_rx, _status_tx) = memory_app();
+
+    assert!(!app.playing());
+}
+
+#[tokio::test]
+async fn can_add_a_track_without_starting_playback() {
+    let (app, mut control_rx, status_tx) = memory_app();
+    let path_1 = PathBuf::from("/home/savanni/Music/Travis Savoie/RPG Toolkit Volume II/05 - Books and Spellcrafting.mp3.mp3");
+    let path_2 = PathBuf::from(
+        "/home/savanni/Music/Travis Savoie/RPG Toolkit Volume II/01 - A Day to Rebuild.mp3.mp3",
+    );
+
+    {
+        app.enable_track(path_1.clone())
+            .await
+            .expect("to enable a track");
+
+        assert_matches!(control_rx.recv().await, Some(AudioControlMessage::EnableTrack(trackspec)) => {
+            assert_eq!(trackspec, TrackSpec{ path: path_1.clone(), volume: Volume::try_from(1.0).unwrap() });
+        });
+
+        status_tx
+            .send(AudioStatusMessage::Status(vec![TrackInfo {
+                path: path_1.clone(),
+                volume: Volume::try_from(1.0).unwrap(),
+                progress: Progress {
+                    current: Duration::from_secs(0),
+                    length: Duration::from_secs(100),
+                },
+            }]))
+            .await
+            .expect("status send to work");
+
+        tokio::time::sleep(Duration::from_millis(1)).await;
+
+        let tracks = app.enabled_tracks();
+        tracks.iter().find(|p| **p == path_1);
+        assert!(!app.playing());
+    }
+
+    {
+        app.enable_track(path_2.clone())
+            .await
+            .expect("to enable a track");
+
+        assert_matches!(control_rx.recv().await, Some(AudioControlMessage::EnableTrack(trackspec)) => {
+            assert_eq!(trackspec, TrackSpec{ path: path_2.clone(), volume: Volume::try_from(1.0).unwrap() });
+        });
+
+        status_tx
+            .send(AudioStatusMessage::Status(vec![
+                TrackInfo {
+                    path: path_1.clone(),
+                    volume: Volume::try_from(1.0).unwrap(),
+                    progress: Progress {
+                        current: Duration::from_secs(0),
+                        length: Duration::from_secs(100),
+                    },
+                },
+                TrackInfo {
+                    path: path_2.clone(),
+                    volume: Volume::try_from(1.0).unwrap(),
+                    progress: Progress {
+                        current: Duration::from_secs(0),
+                        length: Duration::from_secs(100),
+                    },
+                },
+            ]))
+            .await
+            .expect("status send to work");
+
+        tokio::time::sleep(Duration::from_millis(1)).await;
+        let tracks = app.enabled_tracks();
+        tracks.iter().find(|p| **p == path_1);
+        tracks.iter().find(|p| **p == path_2);
+    }
+}
+
+#[tokio::test]
+async fn cannot_start_playback_with_no_tracks() {
+    let (app, control_rx, status_tx) = memory_app();
+    // assert_matches!(app.play(), Err(AppError::NoTracks));
+    unimplemented!()
+}
+
+#[tokio::test]
+async fn can_add_a_track_during_playback() {
+    let (app, control_rx, status_tx) = memory_app();
+    /*
+    app.enable_track(PathBuf::from("/home/savanni/Music/Travis Savoie/RPG Toolkit Volume II/05 - Books and Spellcrafting.mp3.mp3")).expect("to enable a track");
+    app.play().expect("to start playback");
+
+    assert!(app.playing());
+
+    app.enable_track(PathBuf::from(
+        "/home/savanni/Music/Travis Savoie/RPG Toolkit Volume II/01 - A Day to Rebuild.mp3.mp3",
+    ))
+    .expect("to enable another track during playback");
+    */
+    unimplemented!()
+}

gm-dash/server/src/audio_control.rs

@@ -1,138 +0,0 @@
-use gstreamer::{prelude::*, ClockTime, MessageType, MessageView};
-use std::sync::{Arc, RwLock};
-
-pub struct AudioControl {
-    bus: gstreamer::Bus,
-    pipeline: gstreamer::Pipeline,
-    mixer: gstreamer::Element,
-    audio_sink: gstreamer::Element,
-
-    bus_monitor: std::thread::JoinHandle<()>,
-
-    playing: Arc<RwLock<bool>>,
-}
-
-impl Default for AudioControl {
-    fn default() -> Self {
-        let pipeline = gstreamer::Pipeline::new();
-        let bus = pipeline.bus().unwrap();
-
-        let mixer = gstreamer::ElementFactory::find("audiomixer")
-            .unwrap()
-            .load()
-            .unwrap()
-            .create()
-            .build()
-            .unwrap();
-        pipeline.add(&mixer).unwrap();
-
-        let audio_sink = gstreamer::ElementFactory::find("pulsesink")
-            .unwrap()
-            .load()
-            .unwrap()
-            .create()
-            .build()
-            .unwrap();
-        pipeline.add(&audio_sink).unwrap();
-        mixer.link(&audio_sink).unwrap();
-
-        let playing = Arc::new(RwLock::new(false));
-
-        let bus_monitor = std::thread::spawn({
-            let pipeline_object = pipeline.clone().upcast::<gstreamer::Object>();
-            let playing = playing.clone();
-            let bus = bus.clone();
-            move || loop {
-                if let Some(msg) = bus.timed_pop_filtered(
-                    ClockTime::NONE,
-                    &[
-                        MessageType::Error,
-                        MessageType::Eos,
-                        MessageType::StateChanged,
-                    ],
-                ) {
-                    match msg.view() {
-                        MessageView::StateChanged(st) => {
-                            if msg.src() == Some(&pipeline_object) {
-                                *playing.write().unwrap() = st.current() == gstreamer::State::Playing;
-                            }
-                        }
-                        MessageView::Error(err) => {
-                            println!("error: {:?}", err);
-                        }
-                        MessageView::Eos(_) => {
-                            println!("EOS");
-                        }
-                        _ => {
-                            unreachable!();
-                        }
-                    }
-                }
-            }
-        });
-
-        Self {
-            bus,
-            pipeline,
-            mixer,
-            audio_sink,
-
-            bus_monitor,
-
-            playing,
-        }
-    }
-}
-
-impl AudioControl {
-    pub fn play_pause(&self) {
-        if *self.playing.read().unwrap() {
-            self.pipeline.set_state(gstreamer::State::Paused).unwrap();
-        } else {
-            self.pipeline.set_state(gstreamer::State::Playing).unwrap();
-        }
-    }
-
-    pub fn add_track(&mut self, path: String) {
-        let source = gstreamer::ElementFactory::find("filesrc")
-            .unwrap()
-            .load()
-            .unwrap()
-            .create()
-            .property("location", path)
-            .build()
-            .unwrap();
-        self.pipeline.add(&source).unwrap();
-
-        let decoder = gstreamer::ElementFactory::find("decodebin")
-            .unwrap()
-            .load()
-            .unwrap()
-            .create()
-            .build()
-            .unwrap();
-        self.pipeline.add(&decoder).unwrap();
-        source.link(&decoder).unwrap();
-
-        let volume = gstreamer::ElementFactory::find("volume")
-            .unwrap()
-            .load()
-            .unwrap()
-            .create()
-            .property("mute", false)
-            .property("volume", 0.75)
-            .build()
-            .unwrap();
-        self.pipeline.add(&volume).unwrap();
-        volume.link(&self.mixer).unwrap();
-
-        decoder.connect_pad_added(move |_, pad| {
-            let next_pad = volume.static_pad("sink").unwrap();
-            pad.link(&next_pad).unwrap();
-        });
-    }
-
-    pub fn remove_track(&mut self, path: String) {
-        /* Need to run EOS through to a probe on the trailing end of the volume element */
-    }
-}

gm-dash/server/src/audio_control/mod.rs

@@ -0,0 +1,368 @@
+use std::{
+    collections::HashMap,
+    path::PathBuf,
+    sync::{Arc, RwLock},
+    time::Duration,
+};
+
+use gstreamer::{prelude::*, ClockTime, MessageType, MessageView};
+use thiserror::Error;
+use tokio::sync::mpsc::{Receiver, Sender};
+
+use crate::types::{AudioControlMessage, AudioState, AudioStatusMessage, Progress, TrackInfo, TrackSpec};
+
+#[derive(Debug, Error, PartialEq)]
+pub enum AudioError {
+    #[error("No tracks are available to play")]
+    NoTracks,
+
+    #[error("Cannot perform operation in the current state")]
+    InvalidState,
+}
+
+pub struct AudioControl {
+    backend: Box<dyn AudioControlBackend>,
+}
+
+impl AudioControl {
+    pub fn new(backend: impl AudioControlBackend + 'static) -> Self {
+        Self {
+            backend: Box::new(backend),
+        }
+    }
+
+    pub async fn listen(&self, mut control_rx: Receiver<AudioControlMessage>) {
+        while let Some(msg) = control_rx.recv().await {
+            println!("control message: {:?}", msg);
+            match msg {
+                AudioControlMessage::Play => {
+                    self.backend.play().unwrap();
+                }
+                AudioControlMessage::Stop => {
+                    self.backend.stop().unwrap();
+                }
+                AudioControlMessage::Pause => {
+                    self.backend.pause().unwrap();
+                }
+                AudioControlMessage::EnableTrack(spec) => {
+                    self.backend.add_track(spec).unwrap();
+                }
+                AudioControlMessage::DisableTrack(_) => {
+                    unimplemented!()
+                }
+                AudioControlMessage::ReportStatus => {
+                    unimplemented!()
+                }
+            }
+        }
+    }
+
+    pub async fn report(&self, status_tx: Sender<AudioStatusMessage>) {
+        loop {
+            status_tx
+                .send(AudioStatusMessage::Status(AudioState {
+                    playing: self.backend.playing(),
+                    tracks: self.backend.tracks()
+                }))
+                .await
+                .expect("to successfully send a message");
+            let _ = tokio::time::sleep(Duration::from_secs(1)).await;
+        }
+    }
+}
+
+/*
+    pub fn playing(&self) -> bool {
+        self.backend.read().unwrap().playing()
+    }
+
+    pub fn tracks(&self) -> Vec<TrackSpec> {
+        self.backend.read().unwrap().tracks()
+    }
+
+    pub fn play(&self) -> Result<(), AudioError> {
+        self.backend.read().unwrap().play()
+    }
+
+    pub fn stop(&self) -> Result<(), AudioError> {
+        self.backend.read().unwrap().stop()
+    }
+
+    pub fn add_track(&self, track: TrackSpec) -> Result<(), AudioError> {
+        self.backend.write().unwrap().add_track(track)
+    }
+}
+*/
+
+pub trait AudioControlBackend: Send + Sync {
+    fn playing(&self) -> bool;
+
+    fn tracks(&self) -> Vec<TrackInfo>;
+
+    fn play(&self) -> Result<(), AudioError>;
+
+    fn stop(&self) -> Result<(), AudioError>;
+
+    fn pause(&self) -> Result<(), AudioError>;
+
+    fn add_track(&self, track: TrackSpec) -> Result<(), AudioError>;
+
+    fn remove_track(&self, track: TrackSpec) -> Result<(), AudioError>;
+}
+
+/*
+pub struct MemoryBackend {
+    playing: Arc<RwLock<bool>>,
+    tracks: HashMap<PathBuf, TrackSpec>,
+}
+
+impl Default for MemoryBackend {
+    fn default() -> Self {
+        Self {
+            playing: Arc::new(RwLock::new(false)),
+            tracks: HashMap::new(),
+        }
+    }
+}
+
+impl AudioControlBackend for MemoryBackend {
+    fn playing(&self) -> bool {
+        *self.playing.read().unwrap()
+    }
+
+    fn tracks(&self) -> Vec<TrackSpec> {
+        /*
+        self.tracks.iter().cloned().collect()
+        */
+        vec![]
+    }
+
+    fn play(&self) -> Result<(), AudioError> {
+        if self.tracks.is_empty() {
+            return Err(AudioError::NoTracks);
+        }
+
+        let mut playing = self.playing.write().unwrap();
+        if *playing {
+            return Err(AudioError::InvalidState);
+        }
+
+        *playing = true;
+        Ok(())
+    }
+
+    fn stop(&self) -> Result<(), AudioError> {
+        let mut playing = self.playing.write().unwrap();
+        if *playing {
+            *playing = false;
+            Ok(())
+        } else {
+            Err(AudioError::InvalidState)
+        }
+    }
+
+    fn add_track(&mut self, track: TrackSpec) -> Result<(), AudioError> {
+        /*
+        self.tracks.insert(track);
+        */
+        Ok(())
+    }
+
+    fn remove_track(&mut self, track: TrackSpec) -> Result<(), AudioError> {
+        /*
+        self.tracks.remove(&track);
+        */
+        Ok(())
+    }
+}
+*/
+
+struct GStreamerBackendState {
+    playing: bool,
+    tracks: HashMap<PathBuf, TrackInfo>,
+}
+
+impl Default for GStreamerBackendState {
+    fn default() -> Self {
+        Self {
+            playing: false,
+            tracks: HashMap::new(),
+        }
+    }
+}
+
+pub struct GStreamerBackend {
+    bus: gstreamer::Bus,
+    pipeline: gstreamer::Pipeline,
+    mixer: gstreamer::Element,
+    audio_sink: gstreamer::Element,
+    monitor: std::thread::JoinHandle<()>,
+
+    state: Arc<RwLock<GStreamerBackendState>>,
+}
+
+impl Default for GStreamerBackend {
+    fn default() -> Self {
+        let pipeline = gstreamer::Pipeline::new();
+        let bus = pipeline.bus().unwrap();
+
+        let mixer = gstreamer::ElementFactory::find("audiomixer")
+            .unwrap()
+            .load()
+            .unwrap()
+            .create()
+            .build()
+            .unwrap();
+        pipeline.add(&mixer).unwrap();
+
+        let audio_sink = gstreamer::ElementFactory::find("pulsesink")
+            .unwrap()
+            .load()
+            .unwrap()
+            .create()
+            .build()
+            .unwrap();
+        pipeline.add(&audio_sink).unwrap();
+        mixer.link(&audio_sink).unwrap();
+
+        let state = Arc::new(RwLock::new(GStreamerBackendState::default()));
+
+        let monitor = std::thread::spawn({
+            let pipeline_object = pipeline.clone().upcast::<gstreamer::Object>();
+            let state = state.clone();
+            let bus = bus.clone();
+            move || loop {
+                if let Some(msg) = bus.timed_pop_filtered(
+                    ClockTime::NONE,
+                    &[
+                        MessageType::Error,
+                        MessageType::Eos,
+                        MessageType::StateChanged,
+                    ],
+                ) {
+                    match msg.view() {
+                        MessageView::StateChanged(st) => {
+                            if msg.src() == Some(&pipeline_object) {
+                                state.write().unwrap().playing =
+                                    st.current() == gstreamer::State::Playing;
+                            }
+                        }
+                        MessageView::Error(err) => {
+                            println!("error: {:?}", err);
+                        }
+                        MessageView::Eos(_) => {
+                            println!("EOS");
+                        }
+                        _ => {
+                            unreachable!();
+                        }
+                    }
+                }
+            }
+        });
+
+        Self {
+            bus,
+            pipeline,
+            mixer,
+            audio_sink,
+
+            monitor,
+
+            state,
+        }
+    }
+}
+
+impl AudioControlBackend for GStreamerBackend {
+    fn playing(&self) -> bool {
+        self.state.read().unwrap().playing
+    }
+
+    fn tracks(&self) -> Vec<TrackInfo> {
+        vec![]
+    }
+
+    fn play(&self) -> Result<(), AudioError> {
+        if !self.playing() {
+            self.pipeline.set_state(gstreamer::State::Playing).unwrap();
+            Ok(())
+        } else {
+            Err(AudioError::InvalidState)
+        }
+    }
+
+    fn stop(&self) -> Result<(), AudioError> {
+        if self.playing() {
+            self.pipeline.set_state(gstreamer::State::Ready).unwrap();
+            Ok(())
+        } else {
+            Err(AudioError::InvalidState)
+        }
+    }
+
+    fn pause(&self) -> Result<(), AudioError> {
+        if self.playing() {
+            self.pipeline.set_state(gstreamer::State::Paused).unwrap();
+            Ok(())
+        } else {
+            Err(AudioError::InvalidState)
+        }
+    }
+
+    fn add_track(&self, track: TrackSpec) -> Result<(), AudioError> {
+        let mut st = self.state.write().unwrap();
+        st.tracks.insert(track.path.clone(), TrackInfo {
+            path: track.path.clone(),
+            volume: track.volume,
+            progress: Progress {
+                current: Duration::from_secs(0),
+                length: Duration::from_secs(1),
+            },
+        });
+
+        let source = gstreamer::ElementFactory::find("filesrc")
+            .unwrap()
+            .load()
+            .unwrap()
+            .create()
+            .property("location", track.path.to_str().unwrap())
+            .build()
+            .unwrap();
+        self.pipeline.add(&source).unwrap();
+
+        let decoder = gstreamer::ElementFactory::find("decodebin")
+            .unwrap()
+            .load()
+            .unwrap()
+            .create()
+            .build()
+            .unwrap();
+        self.pipeline.add(&decoder).unwrap();
+        source.link(&decoder).unwrap();
+
+        let volume = gstreamer::ElementFactory::find("volume")
+            .unwrap()
+            .load()
+            .unwrap()
+            .create()
+            .property("mute", false)
+            .property("volume", track.volume.as_f64())
+            .build()
+            .unwrap();
+        self.pipeline.add(&volume).unwrap();
+        volume.link(&self.mixer).unwrap();
+
+        decoder.connect_pad_added(move |_, pad| {
+            let next_pad = volume.static_pad("sink").unwrap();
+            pad.link(&next_pad).unwrap();
+        });
+
+        Ok(())
+    }
+
+    fn remove_track(&self, _path: TrackSpec) -> Result<(), AudioError> {
+        unimplemented!()
+        /* Need to run EOS through to a probe on the trailing end of the volume element */
+    }
+}

gm-dash/server/src/main.rs

@@ -1,92 +1,128 @@
+use std::{
+    convert::Infallible,
+    net::{Ipv6Addr, SocketAddrV6},
+    path::PathBuf,
+    sync::Arc,
+};
+
+use app::App;
+use audio_control::{AudioControl, GStreamerBackend};
 use pipewire::{context::Context, main_loop::MainLoop};
 use serde::Deserialize;
-use std::net::{Ipv6Addr, SocketAddrV6};
 use tokio::task::spawn_blocking;
 use warp::{serve, Filter};
 
-mod audio_control;
-
 mod app;
-use app::App;
+mod audio_control;
+mod types;
 
 #[derive(Deserialize)]
 struct PlayTrackParams {
     track_name: String,
 }
 
-async fn server_main(state: App) {
+fn with_app(app: Arc<App>) -> impl Filter<Extract = (Arc<App>,), Error = Infallible> + Clone {
+    warp::any().map(move || app.clone())
+}
+
+async fn server_main(app: Arc<App>) {
     let localhost: Ipv6Addr = "::1".parse().unwrap();
     let server_addr = SocketAddrV6::new(localhost, 3001, 0, 0);
 
     let root = warp::path!().map(|| "ok".to_string());
     let list_output_devices = warp::path!("output_devices").map({
-        let state = state.clone();
+        let app = app.clone();
         move || {
-            let devices = state.audio_devices();
+            let devices = app.audio_devices();
             serde_json::to_string(&devices).unwrap()
         }
     });
 
+    /*
     let list_tracks = warp::path!("tracks").map({
-        let state = state.clone();
+        let app = app.clone();
-        move || serde_json::to_string(&state.tracks()).unwrap()
+        move || serde_json::to_string(&app.tracks()).unwrap()
     });
+    */
 
-    let play_track = warp::put()
+    let enable_track = warp::put()
         .and(warp::path!("playing"))
         .and(warp::body::json())
-        .map({
+        .and(with_app(app.clone()))
-            let state = state.clone();
+        .then(|params: PlayTrackParams, app: Arc<App>| async move {
-            move |params: PlayTrackParams| {
+            println!("enable track");
-                state.play(params.track_name);
+            let _ = app.enable_track(PathBuf::from(params.track_name)).await;
+            "".to_owned()
+        });
+
+    let disable_track = warp::delete()
+        .and(warp::path!("playing"))
+        .and(warp::body::json())
+        .and(with_app(app.clone()))
+        .then(|params: PlayTrackParams, app: Arc<App>| async move {
+            let _ = app.disable_track(&params.track_name);
+            "".to_owned()
+        });
+
+    let play_all = warp::post()
+        .and(warp::path!("play"))
+        .and(with_app(app.clone()))
+        .then({
+            |app: Arc<App>| async move {
+                println!("play_all");
+                let _ = app.play().await;
                 "".to_owned()
             }
         });
 
-    let stop_track = warp::delete()
+    let stop_all = warp::post()
-        .and(warp::path!("playing"))
+        .and(warp::path!("stop"))
-        .and(warp::body::json())
+        .and(with_app(app.clone()))
-        .map({
+        .then({
-            let state = state.clone();
+            |app: Arc<App>| async move {
-            move |params: PlayTrackParams| {
+                let _ = app.stop().await;
-                state.stop(params.track_name);
                 "".to_owned()
             }
         });
 
-    let stop_all_tracks = warp::delete().and(warp::path!("playing")).map({
+    let pause = warp::post()
-        let state = state.clone();
+        .and(warp::path!("pause"))
-        move || {
+        .and(with_app(app.clone()))
-            state.stop_all();
+        .then({
+            |app: Arc<App>| async move {
+                let _ = app.pause().await;
                 "".to_owned()
             }
         });
 
     let now_playing = warp::path!("playing").map({
-        let state = state.clone();
+        let app = app.clone();
-        move || serde_json::to_string(&state.playing()).unwrap()
+        move || serde_json::to_string(&app.playing()).unwrap()
     });
 
     let routes = root
         .or(list_output_devices)
-        .or(list_tracks)
+        // .or(list_tracks)
-        .or(play_track)
+        .or(enable_track)
-        .or(stop_track)
+        .or(disable_track)
-        .or(stop_all_tracks)
+        .or(play_all)
+        .or(stop_all)
+        .or(pause)
         .or(now_playing);
 
     serve(routes).run(server_addr).await;
 }
 
-fn handle_add_audio_device(state: App, props: &pipewire::spa::utils::dict::DictRef) {
+fn handle_add_audio_device(app: App, props: &pipewire::spa::utils::dict::DictRef) {
     if props.get("media.class") == Some("Audio/Sink") {
         if let Some(device_name) = props.get("node.description") {
-            state.add_audio(device_name.to_owned());
+            app.add_audio(device_name.to_owned());
         }
     }
 }
 
-fn pipewire_loop(state: App) -> Result<(), Box<dyn std::error::Error>> {
+/*
+fn pipewire_loop(app: App) -> Result<(), Box<dyn std::error::Error>> {
     let mainloop = MainLoop::new(None)?;
     let context = Context::new(&mainloop)?;
     let core = context.connect(None)?;
@@ -95,10 +131,10 @@ fn pipewire_loop(state: App) -> Result<(), Box<dyn std::error::Error>> {
     let _listener = registry
         .add_listener_local()
         .global({
-            let state = state.clone();
+            let app = app.clone();
             move |global_data| {
                 if let Some(props) = global_data.props {
-                    handle_add_audio_device(state.clone(), props);
+                    handle_add_audio_device(app.clone(), props);
                 }
             }
         })
@@ -108,19 +144,38 @@ fn pipewire_loop(state: App) -> Result<(), Box<dyn std::error::Error>> {
 
     Ok(())
 }
+*/
 
+/*
 fn pipewire_main(state: App) {
     pipewire_loop(state).expect("pipewire should not error");
 }
+*/
 
 #[tokio::main]
 async fn main() {
-    let state = App::default();
+    gstreamer::init();
 
-    spawn_blocking({
+    let (audio_control_tx, audio_control_rx) = tokio::sync::mpsc::channel(5);
-        let state = state.clone();
+    let (audio_status_tx, audio_status_rx) = tokio::sync::mpsc::channel(5);
-        move || pipewire_main(state)
+
+    let app = Arc::new(App::new(audio_control_tx, audio_status_rx));
+    let audio_controller = Arc::new(AudioControl::new(GStreamerBackend::default()));
+    tokio::spawn({
+        let audio_controller = audio_controller.clone();
+        async move { audio_controller.listen(audio_control_rx).await }
+    });
+    tokio::spawn({
+        let audio_controller = audio_controller.clone();
+        async move { audio_controller.report(audio_status_tx).await }
     });
 
-    server_main(state.clone()).await;
+    /*
+    spawn_blocking({
+        let app = app.clone();
+        move || pipewire_main(state)
+    });
+    */
+
+    server_main(app.clone()).await;
 }

gm-dash/server/src/types.rs

@@ -0,0 +1,102 @@
+use std::{ops::Deref, path::PathBuf, time::Duration};
+
+use thiserror::Error;
+
+use crate::audio_control::AudioError;
+
+#[derive(Debug, Error, PartialEq)]
+pub enum AppError {
+    #[error("Operation invalid with no tracks enabled")]
+    NoTracks,
+
+    #[error("Operation is invalid in the current state")]
+    InvalidState,
+}
+
+impl From<AudioError> for AppError {
+    fn from(err: AudioError) -> Self {
+        match err {
+            AudioError::NoTracks => Self::NoTracks,
+            AudioError::InvalidState => Self::InvalidState,
+        }
+    }
+}
+
+#[derive(Clone, Debug, PartialEq, PartialOrd)]
+pub struct TrackSpec {
+    pub path: PathBuf,
+    pub volume: Volume,
+}
+
+#[derive(Clone, Debug)]
+pub struct Progress {
+    pub current: Duration,
+    pub length: Duration,
+}
+
+#[derive(Debug, Error, PartialEq)]
+pub enum VolumeError {
+    #[error("The specified volume is out of range and must be between 0.0 and 1.0")]
+    OutOfRange,
+}
+
+#[derive(Clone, Copy, Debug, PartialEq, PartialOrd)]
+pub struct Volume(f32);
+
+impl Volume {
+    pub fn as_f32(&self) -> f32 {
+        self.0
+    }
+
+    pub fn as_f64(&self) -> f64 {
+        self.0.into()
+    }
+}
+
+impl TryFrom<f32> for Volume {
+    type Error = VolumeError;
+    fn try_from(val: f32) -> Result<Self, Self::Error> {
+        if val < 0. || val > 1. {
+            return Err(VolumeError::OutOfRange);
+        }
+
+        Ok(Self(val))
+    }
+}
+
+impl From<Volume> for f32 {
+    fn from(val: Volume) -> f32 {
+        val.0
+    }
+}
+
+#[derive(Clone, Debug)]
+pub enum AudioControlMessage {
+    Play,
+    Pause,
+    Stop,
+    EnableTrack(TrackSpec),
+    DisableTrack(PathBuf),
+    ReportStatus,
+}
+
+#[derive(Clone, Debug)]
+pub struct TrackInfo {
+    pub path: PathBuf,
+    pub volume: Volume,
+    pub progress: Progress,
+}
+
+#[derive(Clone, Debug)]
+pub struct AudioState {
+    pub playing: bool,
+    pub tracks: Vec<TrackInfo>,
+}
+
+#[derive(Debug)]
+pub enum AudioStatusMessage {
+    Playing,
+    Pausing,
+    Status(AudioState),
+    AudioError(AudioError),
+}