Add features and start writing interfaces

engine/Cargo.toml

@@ -4,5 +4,10 @@ version = "0.1.0"
 edition = "2024"
 
 [dependencies]
-jack = "0.13.3"
+coreaudio-rs = { version = "0.13.0", optional = true }
+jack = {version = "0.13.3", optional = true }
 lib = { path = "../lib/" }
+
+[features]
+jack = ["dep:jack"]
+coreaudio = ["dep:coreaudio-rs"]

engine/src/audio_engine/mod.rs

@@ -0,0 +1,12 @@
+mod jack;
+mod coreaudio;
+
+trait AudioBackend {
+    // Start a audio backend client
+    // It should be executed either on the startup,
+    // or when the audio backend is switched
+    fn start_client();
+    // Initialization of the client should happen 
+    // when a project is opened.
+    fn init_client();
+}

engine/src/main.rs

@@ -1,3 +1,5 @@
+mod audio_engine;
+
 use lib::{self, metadata::Metadata, track::Track};
 
 fn main() {