refactor: switch ambient audio to user-supplied assets

1 files changed, 109 insertions, 8 deletions

diff --git a/src-tauri/src/audio.rs b/src-tauri/src/audio.rs
index a439a0c..11c970e 100644
--- a/src-tauri/src/audio.rs
+++ b/src-tauri/src/audio.rs
@@ -1,7 +1,7 @@
 use rodio::{Decoder, OutputStream, OutputStreamHandle, Sink, Source};
 use std::fs::File;
 use std::io::BufReader;
-use std::path::PathBuf;
+use std::path::{Path, PathBuf};
 use std::sync::{Arc, Mutex};
 use std::thread;
 
@@ -17,6 +17,22 @@ pub enum AmbientSound {
     WhiteNoise,
 }
 
+const EXPECTED_AUDIO_FILES: [&str; 3] = ["rain.ogg", "cafe.ogg", "white_noise.ogg"];
+
+pub fn directory_has_any_audio_files(dir: &Path) -> bool {
+    EXPECTED_AUDIO_FILES
+        .iter()
+        .any(|filename| dir.join(filename).is_file())
+}
+
+pub fn choose_audio_dir(app_data_audio_dir: PathBuf, bundled_audio_dir: PathBuf) -> PathBuf {
+    if directory_has_any_audio_files(&app_data_audio_dir) {
+        app_data_audio_dir
+    } else {
+        bundled_audio_dir
+    }
+}
+
 impl AmbientSound {
     pub fn filename(&self) -> &'static str {
         match self {
@@ -51,11 +67,16 @@ pub struct AudioEngine {
     volume: f32,
     ducked: bool,
     duck_volume: f32,
-    audio_dir: PathBuf,
+    app_data_audio_dir: PathBuf,
+    bundled_audio_dir: PathBuf,
 }
 
 impl AudioEngine {
-    fn new_with_handle(stream_handle: OutputStreamHandle, audio_dir: PathBuf) -> Self {
+    fn new_with_handle(
+        stream_handle: OutputStreamHandle,
+        app_data_audio_dir: PathBuf,
+        bundled_audio_dir: PathBuf,
+    ) -> Self {
         Self {
             stream_handle,
             sink: None,
@@ -63,14 +84,33 @@ impl AudioEngine {
             volume: 0.5,
             ducked: false,
             duck_volume: 0.2,
-            audio_dir,
+            app_data_audio_dir,
+            bundled_audio_dir,
+        }
+    }
+
+    fn resolve_audio_path(&self, filename: &str) -> PathBuf {
+        let app_data_path = self.app_data_audio_dir.join(filename);
+        if app_data_path.is_file() {
+            app_data_path
+        } else {
+            let bundled_path = self.bundled_audio_dir.join(filename);
+            if bundled_path.is_file() {
+                bundled_path
+            } else {
+                choose_audio_dir(
+                    self.app_data_audio_dir.clone(),
+                    self.bundled_audio_dir.clone(),
+                )
+                .join(filename)
+            }
         }
     }
 
     pub fn play(&mut self, sound: AmbientSound) -> Result<(), String> {
         self.stop();
         let filename = sound.filename();
-        let path = self.audio_dir.join(filename);
+        let path = self.resolve_audio_path(filename);
         let file = File::open(&path).map_err(|e| format!("Cannot open {filename}: {e}"))?;
         let source = Decoder::new(BufReader::new(file))
             .map_err(|e| format!("Decode error: {e}"))?;
@@ -125,6 +165,11 @@ impl AudioEngine {
     pub fn volume(&self) -> f32 {
         self.volume
     }
+
+    pub fn has_any_audio_files(&self) -> bool {
+        directory_has_any_audio_files(&self.app_data_audio_dir)
+            || directory_has_any_audio_files(&self.bundled_audio_dir)
+    }
 }
 
 pub fn should_duck_for_phase(phase: TimerPhase) -> bool {
@@ -139,14 +184,14 @@ pub struct AudioState(pub Arc<Mutex<Option<AudioEngine>>>);
 ///
 /// Spawns a dedicated thread to keep `OutputStream` alive (it is `!Send`).
 /// Returns `AudioState` whose inner `Option` is `None` if no audio device exists.
-pub fn init_audio(audio_dir: PathBuf) -> AudioState {
+pub fn init_audio(app_data_audio_dir: PathBuf, bundled_audio_dir: PathBuf) -> AudioState {
     let state: Arc<Mutex<Option<AudioEngine>>> = Arc::new(Mutex::new(None));
     let state_clone = Arc::clone(&state);
 
     thread::spawn(move || {
         match OutputStream::try_default() {
             Ok((_stream, handle)) => {
-                let engine = AudioEngine::new_with_handle(handle, audio_dir);
+                let engine = AudioEngine::new_with_handle(handle, app_data_audio_dir, bundled_audio_dir);
                 {
                     let mut guard = state_clone.lock().unwrap();
                     *guard = Some(engine);
@@ -172,9 +217,29 @@ pub fn init_audio(audio_dir: PathBuf) -> AudioState {
 
 #[cfg(test)]
 mod tests {
-    use super::should_duck_for_phase;
+    use std::fs;
+    use std::path::Path;
+    use std::time::{SystemTime, UNIX_EPOCH};
+
+    use super::{choose_audio_dir, directory_has_any_audio_files, should_duck_for_phase};
     use crate::state::TimerPhase;
 
+    fn temp_path(label: &str) -> std::path::PathBuf {
+        let unique = SystemTime::now()
+            .duration_since(UNIX_EPOCH)
+            .unwrap()
+            .as_nanos();
+        std::env::temp_dir().join(format!("solstice-audio-{label}-{unique}"))
+    }
+
+    fn make_dir(path: &Path) {
+        fs::create_dir_all(path).unwrap();
+    }
+
+    fn write_audio_file(dir: &Path, name: &str) {
+        fs::write(dir.join(name), b"test-audio").unwrap();
+    }
+
     #[test]
     fn work_phase_does_not_duck() {
         assert!(!should_duck_for_phase(TimerPhase::Work));
@@ -185,4 +250,40 @@ mod tests {
         assert!(should_duck_for_phase(TimerPhase::ShortBreak));
         assert!(should_duck_for_phase(TimerPhase::LongBreak));
     }
+
+    #[test]
+    fn detects_expected_audio_files_in_directory() {
+        let dir = temp_path("detect-files");
+        make_dir(&dir);
+        write_audio_file(&dir, "white_noise.ogg");
+
+        assert!(directory_has_any_audio_files(&dir));
+    }
+
+    #[test]
+    fn prefers_app_data_audio_when_files_exist_there() {
+        let app_dir = temp_path("app-data");
+        let bundled_dir = temp_path("bundled");
+        make_dir(&app_dir);
+        make_dir(&bundled_dir);
+        write_audio_file(&app_dir, "rain.ogg");
+        write_audio_file(&bundled_dir, "cafe.ogg");
+
+        let chosen = choose_audio_dir(app_dir.clone(), bundled_dir.clone());
+
+        assert_eq!(chosen, app_dir);
+    }
+
+    #[test]
+    fn falls_back_to_bundled_audio_when_app_data_is_empty() {
+        let app_dir = temp_path("app-data-empty");
+        let bundled_dir = temp_path("bundled-fallback");
+        make_dir(&app_dir);
+        make_dir(&bundled_dir);
+        write_audio_file(&bundled_dir, "rain.ogg");
+
+        let chosen = choose_audio_dir(app_dir, bundled_dir.clone());
+
+        assert_eq!(chosen, bundled_dir);
+    }
 }