Initial implementation of qobuz-qt
- Rust backend (qobuz-backend static lib): Qobuz API client (reqwest/tokio), Symphonia audio decoder, CPAL audio output, extern "C" FFI bridge - Qt 6 frontend mirroring spotify-qt layout: toolbar with playback controls, left library dock, central track list, right search panel - Auth: email/password login with MD5-signed requests; session token persisted via QSettings - Playback: double-click a track → Rust fetches stream URL → Symphonia decodes → CPAL outputs to default audio device - Dark Fusion palette matching spotify-qt feel Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
This commit is contained in:
joren
486
rust/src/lib.rs
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486
rust/src/lib.rs
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@@ -0,0 +1,486 @@
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//! qobuz-backend: C-ABI library consumed by the Qt frontend.
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//!
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//! Event type constants – second argument of EventCallback:
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//! 0 EV_LOGIN_OK { "token": "…", "user": { … } }
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//! 1 EV_LOGIN_ERR { "error": "…" }
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//! 2 EV_SEARCH_OK SearchCatalogDto
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//! 3 EV_SEARCH_ERR { "error": "…" }
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//! 4 EV_ALBUM_OK AlbumDto
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//! 5 EV_ALBUM_ERR { "error": "…" }
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//! 6 EV_ARTIST_OK ArtistDto
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//! 7 EV_ARTIST_ERR { "error": "…" }
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//! 8 EV_PLAYLIST_OK PlaylistDto
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//! 9 EV_PLAYLIST_ERR { "error": "…" }
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//! 10 EV_FAV_TRACKS_OK { "items": […], "total": N }
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//! 11 EV_FAV_ALBUMS_OK { "items": […], "total": N }
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//! 12 EV_FAV_ARTISTS_OK { "items": […], "total": N }
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//! 13 EV_PLAYLISTS_OK { "items": […], "total": N }
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//! 14 EV_TRACK_CHANGED TrackDto
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//! 15 EV_STATE_CHANGED { "state": "playing"|"paused"|"idle"|"error" }
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//! 16 EV_POSITION { "position": u64, "duration": u64 }
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//! 17 EV_TRACK_URL_OK TrackFileUrlDto
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//! 18 EV_TRACK_URL_ERR { "error": "…" }
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//! 19 EV_GENERIC_ERR { "error": "…" }
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mod api;
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mod player;
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use std::{
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ffi::{CStr, CString},
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os::raw::{c_char, c_int, c_void},
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sync::Arc,
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};
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use api::{Format, QobuzClient};
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use player::{Player, PlayerState};
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use tokio::runtime::Runtime;
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use tokio::sync::Mutex;
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// ---------- Send-safe raw pointer wrapper ----------
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/// Wraps a `*mut c_void` so it can cross thread boundaries.
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/// SAFETY: The Qt QobuzBackend object is kept alive for the Backend's lifetime
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/// and callbacks only call QMetaObject::invokeMethod (thread-safe Qt API).
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#[derive(Clone, Copy)]
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struct SendPtr(*mut c_void);
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unsafe impl Send for SendPtr {}
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unsafe impl Sync for SendPtr {}
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// ---------- Event type constants ----------
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pub const EV_LOGIN_OK: c_int = 0;
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pub const EV_LOGIN_ERR: c_int = 1;
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pub const EV_SEARCH_OK: c_int = 2;
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pub const EV_SEARCH_ERR: c_int = 3;
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pub const EV_ALBUM_OK: c_int = 4;
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pub const EV_ALBUM_ERR: c_int = 5;
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pub const EV_ARTIST_OK: c_int = 6;
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pub const EV_ARTIST_ERR: c_int = 7;
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pub const EV_PLAYLIST_OK: c_int = 8;
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pub const EV_PLAYLIST_ERR: c_int = 9;
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pub const EV_FAV_TRACKS_OK: c_int = 10;
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pub const EV_FAV_ALBUMS_OK: c_int = 11;
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pub const EV_FAV_ARTISTS_OK: c_int = 12;
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pub const EV_PLAYLISTS_OK: c_int = 13;
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pub const EV_TRACK_CHANGED: c_int = 14;
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pub const EV_STATE_CHANGED: c_int = 15;
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pub const EV_POSITION: c_int = 16;
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pub const EV_TRACK_URL_OK: c_int = 17;
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pub const EV_TRACK_URL_ERR: c_int = 18;
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pub const EV_GENERIC_ERR: c_int = 19;
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// ---------- Callback ----------
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pub type EventCallback = unsafe extern "C" fn(*mut c_void, c_int, *const c_char);
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// ---------- Backend ----------
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struct BackendInner {
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client: Arc<Mutex<QobuzClient>>,
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player: Player,
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rt: Runtime,
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cb: EventCallback,
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ud: SendPtr,
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}
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pub struct Backend(BackendInner);
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// ---------- Helpers ----------
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fn call_cb(cb: EventCallback, ud: SendPtr, ev: c_int, json: &str) {
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let cstr = CString::new(json).unwrap_or_else(|_| CString::new("{}").unwrap());
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unsafe { cb(ud.0, ev, cstr.as_ptr()) };
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}
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fn err_json(msg: &str) -> String {
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serde_json::json!({ "error": msg }).to_string()
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}
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/// Spawn a Send + 'static future on the backend's Tokio runtime.
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fn spawn<F>(inner: &BackendInner, f: F)
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where
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F: std::future::Future<Output = ()> + Send + 'static,
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{
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inner.rt.spawn(f);
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}
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// ---------- Construction / destruction ----------
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#[no_mangle]
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pub unsafe extern "C" fn qobuz_backend_new(
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event_cb: EventCallback,
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userdata: *mut c_void,
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) -> *mut Backend {
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let rt = Runtime::new().expect("tokio runtime");
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let client = Arc::new(Mutex::new(QobuzClient::new().expect("QobuzClient")));
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let player = Player::new();
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Box::into_raw(Box::new(Backend(BackendInner {
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client,
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player,
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rt,
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cb: event_cb,
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ud: SendPtr(userdata),
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})))
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}
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#[no_mangle]
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pub unsafe extern "C" fn qobuz_backend_free(ptr: *mut Backend) {
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if !ptr.is_null() {
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drop(Box::from_raw(ptr));
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}
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}
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// ---------- Auth ----------
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#[no_mangle]
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pub unsafe extern "C" fn qobuz_backend_login(
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ptr: *mut Backend,
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email: *const c_char,
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password: *const c_char,
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) {
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let inner = &(*ptr).0;
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let email = CStr::from_ptr(email).to_string_lossy().into_owned();
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let password = CStr::from_ptr(password).to_string_lossy().into_owned();
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let client = inner.client.clone();
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let cb = inner.cb;
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let ud = inner.ud;
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spawn(inner, async move {
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let result = client.lock().await.login(&email, &password).await;
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let (ev, json) = match result {
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Ok(resp) => {
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let token = resp
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.oauth2.as_ref().and_then(|o| o.access_token.as_deref())
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.or(resp.user_auth_token.as_deref())
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.unwrap_or("")
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.to_string();
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let user_val = resp.user.as_ref()
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.map(|u| serde_json::to_value(u).unwrap_or_default())
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.unwrap_or_default();
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(EV_LOGIN_OK, serde_json::json!({"token": token, "user": user_val}).to_string())
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}
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Err(e) => (EV_LOGIN_ERR, err_json(&e.to_string())),
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};
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call_cb(cb, ud, ev, &json);
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});
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}
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#[no_mangle]
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pub unsafe extern "C" fn qobuz_backend_set_token(ptr: *mut Backend, token: *const c_char) {
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let inner = &(*ptr).0;
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let token = CStr::from_ptr(token).to_string_lossy().into_owned();
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let client = inner.client.clone();
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// blocking_lock is available on tokio::sync::Mutex when not in an async context
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inner.rt.spawn(async move {
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client.lock().await.set_auth_token(token);
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});
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}
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// ---------- Search ----------
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#[no_mangle]
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pub unsafe extern "C" fn qobuz_backend_search(
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ptr: *mut Backend,
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query: *const c_char,
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offset: u32,
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limit: u32,
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) {
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let inner = &(*ptr).0;
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let query = CStr::from_ptr(query).to_string_lossy().into_owned();
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let client = inner.client.clone();
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let cb = inner.cb; let ud = inner.ud;
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spawn(inner, async move {
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let result = client.lock().await.search(&query, offset, limit).await;
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let (ev, json) = match result {
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Ok(r) => (EV_SEARCH_OK, serde_json::to_string(&r).unwrap_or_default()),
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Err(e) => (EV_SEARCH_ERR, err_json(&e.to_string())),
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};
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call_cb(cb, ud, ev, &json);
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});
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}
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// ---------- Album ----------
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#[no_mangle]
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pub unsafe extern "C" fn qobuz_backend_get_album(ptr: *mut Backend, album_id: *const c_char) {
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let inner = &(*ptr).0;
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let album_id = CStr::from_ptr(album_id).to_string_lossy().into_owned();
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let client = inner.client.clone();
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let cb = inner.cb; let ud = inner.ud;
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spawn(inner, async move {
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let result = client.lock().await.get_album(&album_id).await;
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let (ev, json) = match result {
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Ok(r) => (EV_ALBUM_OK, serde_json::to_string(&r).unwrap_or_default()),
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Err(e) => (EV_ALBUM_ERR, err_json(&e.to_string())),
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};
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call_cb(cb, ud, ev, &json);
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});
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}
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// ---------- Artist ----------
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#[no_mangle]
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pub unsafe extern "C" fn qobuz_backend_get_artist(ptr: *mut Backend, artist_id: i64) {
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let inner = &(*ptr).0;
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let client = inner.client.clone();
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let cb = inner.cb; let ud = inner.ud;
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spawn(inner, async move {
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let result = client.lock().await.get_artist(artist_id).await;
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let (ev, json) = match result {
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Ok(r) => (EV_ARTIST_OK, serde_json::to_string(&r).unwrap_or_default()),
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Err(e) => (EV_ARTIST_ERR, err_json(&e.to_string())),
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};
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call_cb(cb, ud, ev, &json);
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});
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}
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// ---------- Playlist ----------
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#[no_mangle]
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pub unsafe extern "C" fn qobuz_backend_get_playlist(
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ptr: *mut Backend,
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playlist_id: i64,
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offset: u32,
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limit: u32,
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) {
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let inner = &(*ptr).0;
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let client = inner.client.clone();
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let cb = inner.cb; let ud = inner.ud;
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spawn(inner, async move {
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let result = client.lock().await.get_playlist(playlist_id, offset, limit).await;
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let (ev, json) = match result {
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Ok(r) => (EV_PLAYLIST_OK, serde_json::to_string(&r).unwrap_or_default()),
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Err(e) => (EV_PLAYLIST_ERR, err_json(&e.to_string())),
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};
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call_cb(cb, ud, ev, &json);
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});
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}
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// ---------- Favorites ----------
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#[no_mangle]
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pub unsafe extern "C" fn qobuz_backend_get_fav_tracks(ptr: *mut Backend, offset: u32, limit: u32) {
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let inner = &(*ptr).0;
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let client = inner.client.clone();
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let cb = inner.cb; let ud = inner.ud;
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spawn(inner, async move {
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let result = client.lock().await.get_fav_tracks(offset, limit).await;
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let (ev, json) = match result {
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Ok(r) => (EV_FAV_TRACKS_OK, serde_json::to_string(&r).unwrap_or_default()),
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Err(e) => (EV_GENERIC_ERR, err_json(&e.to_string())),
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};
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call_cb(cb, ud, ev, &json);
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});
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}
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#[no_mangle]
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pub unsafe extern "C" fn qobuz_backend_get_fav_albums(ptr: *mut Backend, offset: u32, limit: u32) {
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let inner = &(*ptr).0;
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let client = inner.client.clone();
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let cb = inner.cb; let ud = inner.ud;
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spawn(inner, async move {
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let result = client.lock().await.get_fav_albums(offset, limit).await;
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let (ev, json) = match result {
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Ok(r) => (EV_FAV_ALBUMS_OK, serde_json::to_string(&r).unwrap_or_default()),
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Err(e) => (EV_GENERIC_ERR, err_json(&e.to_string())),
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};
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call_cb(cb, ud, ev, &json);
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});
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}
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#[no_mangle]
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pub unsafe extern "C" fn qobuz_backend_get_fav_artists(ptr: *mut Backend, offset: u32, limit: u32) {
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let inner = &(*ptr).0;
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let client = inner.client.clone();
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let cb = inner.cb; let ud = inner.ud;
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spawn(inner, async move {
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let result = client.lock().await.get_fav_artists(offset, limit).await;
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let (ev, json) = match result {
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Ok(r) => (EV_FAV_ARTISTS_OK, serde_json::to_string(&r).unwrap_or_default()),
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Err(e) => (EV_GENERIC_ERR, err_json(&e.to_string())),
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};
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call_cb(cb, ud, ev, &json);
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});
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}
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#[no_mangle]
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pub unsafe extern "C" fn qobuz_backend_get_user_playlists(ptr: *mut Backend, offset: u32, limit: u32) {
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let inner = &(*ptr).0;
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let client = inner.client.clone();
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let cb = inner.cb; let ud = inner.ud;
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spawn(inner, async move {
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let result = client.lock().await.get_user_playlists(offset, limit).await;
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let (ev, json) = match result {
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Ok(r) => {
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let items = r.playlists.as_ref().and_then(|p| p.items.as_ref()).cloned().unwrap_or_default();
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let total = r.playlists.as_ref().and_then(|p| p.total).unwrap_or(0);
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(EV_PLAYLISTS_OK, serde_json::json!({"items": items, "total": total}).to_string())
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}
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Err(e) => (EV_GENERIC_ERR, err_json(&e.to_string())),
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};
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call_cb(cb, ud, ev, &json);
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});
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}
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// ---------- Playback ----------
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#[no_mangle]
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pub unsafe extern "C" fn qobuz_backend_play_track(
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ptr: *mut Backend,
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track_id: i64,
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format_id: i32,
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) {
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let inner = &(*ptr).0;
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let client = inner.client.clone();
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let cb = inner.cb; let ud = inner.ud;
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let format = Format::from_id(format_id);
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let cmd_tx = inner.player.cmd_tx.clone();
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let status = inner.player.status.clone();
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spawn(inner, async move {
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// 1. Track metadata
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let track = match client.lock().await.get_track(track_id).await {
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Ok(t) => t,
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Err(e) => { call_cb(cb, ud, EV_TRACK_URL_ERR, &err_json(&e.to_string())); return; }
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};
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// 2. Stream URL
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let url_dto = match client.lock().await.get_track_url(track_id, format).await {
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Ok(u) => u,
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Err(e) => { call_cb(cb, ud, EV_TRACK_URL_ERR, &err_json(&e.to_string())); return; }
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};
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let url = match url_dto.url {
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Some(u) => u,
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None => { call_cb(cb, ud, EV_TRACK_URL_ERR, &err_json("no stream URL")); return; }
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};
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// 3. Notify track change
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if let Ok(j) = serde_json::to_string(&track) {
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call_cb(cb, ud, EV_TRACK_CHANGED, &j);
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}
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// 4. Update status + send play command
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*status.current_track.lock().unwrap() = Some(track.clone());
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if let Some(dur) = track.duration {
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status.duration_secs.store(dur as u64, std::sync::atomic::Ordering::Relaxed);
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}
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let _ = cmd_tx.send(player::PlayerCommand::Play(player::TrackInfo { track, url, format }));
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// 5. State notification
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call_cb(cb, ud, EV_STATE_CHANGED, r#"{"state":"playing"}"#);
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});
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}
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#[no_mangle]
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pub unsafe extern "C" fn qobuz_backend_pause(ptr: *mut Backend) {
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let inner = &(*ptr).0;
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inner.player.pause();
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call_cb(inner.cb, inner.ud, EV_STATE_CHANGED, r#"{"state":"paused"}"#);
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}
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#[no_mangle]
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pub unsafe extern "C" fn qobuz_backend_resume(ptr: *mut Backend) {
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let inner = &(*ptr).0;
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inner.player.resume();
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call_cb(inner.cb, inner.ud, EV_STATE_CHANGED, r#"{"state":"playing"}"#);
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}
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#[no_mangle]
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pub unsafe extern "C" fn qobuz_backend_stop(ptr: *mut Backend) {
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let inner = &(*ptr).0;
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inner.player.stop();
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call_cb(inner.cb, inner.ud, EV_STATE_CHANGED, r#"{"state":"idle"}"#);
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}
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#[no_mangle]
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pub unsafe extern "C" fn qobuz_backend_set_volume(ptr: *mut Backend, volume: u8) {
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(*ptr).0.player.set_volume(volume);
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}
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#[no_mangle]
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pub unsafe extern "C" fn qobuz_backend_get_position(ptr: *const Backend) -> u64 {
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(*ptr).0.player.status.get_position()
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}
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#[no_mangle]
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pub unsafe extern "C" fn qobuz_backend_get_duration(ptr: *const Backend) -> u64 {
|
||||
(*ptr).0.player.status.get_duration()
|
||||
}
|
||||
|
||||
#[no_mangle]
|
||||
pub unsafe extern "C" fn qobuz_backend_get_volume(ptr: *const Backend) -> u8 {
|
||||
(*ptr).0.player.status.get_volume()
|
||||
}
|
||||
|
||||
#[no_mangle]
|
||||
pub unsafe extern "C" fn qobuz_backend_get_state(ptr: *const Backend) -> c_int {
|
||||
match (*ptr).0.player.status.get_state() {
|
||||
PlayerState::Playing => 1,
|
||||
PlayerState::Paused => 2,
|
||||
_ => 0,
|
||||
}
|
||||
}
|
||||
|
||||
#[no_mangle]
|
||||
pub unsafe extern "C" fn qobuz_backend_take_track_finished(ptr: *mut Backend) -> c_int {
|
||||
let finished = (*ptr).0.player.status.track_finished
|
||||
.swap(false, std::sync::atomic::Ordering::SeqCst);
|
||||
if finished { 1 } else { 0 }
|
||||
}
|
||||
|
||||
// ---------- Favorites modification ----------
|
||||
|
||||
#[no_mangle]
|
||||
pub unsafe extern "C" fn qobuz_backend_add_fav_track(ptr: *mut Backend, track_id: i64) {
|
||||
let inner = &(*ptr).0;
|
||||
let client = inner.client.clone();
|
||||
let cb = inner.cb; let ud = inner.ud;
|
||||
spawn(inner, async move {
|
||||
if let Err(e) = client.lock().await.add_fav_track(track_id).await {
|
||||
call_cb(cb, ud, EV_GENERIC_ERR, &err_json(&e.to_string()));
|
||||
}
|
||||
});
|
||||
}
|
||||
|
||||
#[no_mangle]
|
||||
pub unsafe extern "C" fn qobuz_backend_remove_fav_track(ptr: *mut Backend, track_id: i64) {
|
||||
let inner = &(*ptr).0;
|
||||
let client = inner.client.clone();
|
||||
let cb = inner.cb; let ud = inner.ud;
|
||||
spawn(inner, async move {
|
||||
if let Err(e) = client.lock().await.remove_fav_track(track_id).await {
|
||||
call_cb(cb, ud, EV_GENERIC_ERR, &err_json(&e.to_string()));
|
||||
}
|
||||
});
|
||||
}
|
||||
|
||||
#[no_mangle]
|
||||
pub unsafe extern "C" fn qobuz_backend_add_fav_album(ptr: *mut Backend, album_id: *const c_char) {
|
||||
let inner = &(*ptr).0;
|
||||
let album_id = CStr::from_ptr(album_id).to_string_lossy().into_owned();
|
||||
let client = inner.client.clone();
|
||||
let cb = inner.cb; let ud = inner.ud;
|
||||
spawn(inner, async move {
|
||||
if let Err(e) = client.lock().await.add_fav_album(&album_id).await {
|
||||
call_cb(cb, ud, EV_GENERIC_ERR, &err_json(&e.to_string()));
|
||||
}
|
||||
});
|
||||
}
|
||||
|
||||
#[no_mangle]
|
||||
pub unsafe extern "C" fn qobuz_backend_remove_fav_album(ptr: *mut Backend, album_id: *const c_char) {
|
||||
let inner = &(*ptr).0;
|
||||
let album_id = CStr::from_ptr(album_id).to_string_lossy().into_owned();
|
||||
let client = inner.client.clone();
|
||||
let cb = inner.cb; let ud = inner.ud;
|
||||
spawn(inner, async move {
|
||||
if let Err(e) = client.lock().await.remove_fav_album(&album_id).await {
|
||||
call_cb(cb, ud, EV_GENERIC_ERR, &err_json(&e.to_string()));
|
||||
}
|
||||
});
|
||||
}
|
||||
Reference in New Issue
Block a user