holdings: a member of a Space publishes what they hold as room-salted album keys, sealed to the room, so "who has this" is answered while they are offline

src-tauri/src/spaces.rs

@@ -66,6 +66,11 @@ struct SpaceRecord {
     /// room is not consent to be watched in it.
     #[serde(default)]
     share_listens: bool,
+    /// Whether this device publishes what it HOLDS into this Space — album
+    /// keys sealed to the room, never files (`holdings.rs`). Per Space and
+    /// off until asked, for the same reason as listens.
+    #[serde(default)]
+    share_holdings: bool,
     /// The last listen posted here — what, and when. A reload or a restart
     /// re-reports whatever is already past the player's threshold, and this
     /// is the only side that knows what a room was last told.
@@ -153,6 +158,8 @@ pub struct SpaceView {
     pub can_post: bool,
     /// Whether THIS device posts what it plays here.
     pub share_listens: bool,
+    /// Whether THIS device publishes its holdings here.
+    pub share_holdings: bool,
     pub has_key: bool,
     /// The contract exists on the network (a Space someone invited us to
     /// may not have propagated to this node yet).
@@ -226,13 +233,13 @@ fn rand32() -> [u8; 32] {
     rand::thread_rng().fill_bytes(&mut n);
     n
 }
-fn b58(bytes: &[u8]) -> String {
+pub(crate) fn b58(bytes: &[u8]) -> String {
     bs58::encode(bytes).into_string()
 }
-fn key_of(s: &str) -> Result<[u8; 32], String> {
+pub(crate) fn key_of(s: &str) -> Result<[u8; 32], String> {
     inbox::key_of(s)
 }
-fn id_of(s: &str) -> Result<[u8; 16], String> {
+pub(crate) fn id_of(s: &str) -> Result<[u8; 16], String> {
     bs58::decode(s)
         .into_vec()
         .map_err(|e| format!("bad id: {e}"))?
@@ -250,7 +257,7 @@ fn cap(s: &str, max: usize) -> String {
     }
     s[..end].to_string()
 }
-fn record_id(owner: &str, space_id: &str) -> String {
+pub(crate) fn record_id(owner: &str, space_id: &str) -> String {
     format!("{owner}:{space_id}")
 }
 
@@ -281,7 +288,7 @@ fn save(app: &tauri::AppHandle, l: &Ledger) -> Result<(), String> {
     Ok(())
 }
 
-async fn my_key(app: &tauri::AppHandle) -> Result<[u8; 32], String> {
+pub(crate) async fn my_key(app: &tauri::AppHandle) -> Result<[u8; 32], String> {
     let adapter = app.state::<AppState>().freenet.clone();
     let info = persona::current(&adapter)
         .await?
@@ -404,6 +411,7 @@ fn view_of(app: &tauri::AppHandle, rec: &SpaceRecord, state: &sp::SpaceState, me
             listens: vec![],
             can_post: false,
             share_listens: rec.share_listens,
+            share_holdings: rec.share_holdings,
             has_key: false,
             reachable,
         };
@@ -490,6 +498,7 @@ fn view_of(app: &tauri::AppHandle, rec: &SpaceRecord, state: &sp::SpaceState, me
             .collect(),
         can_post: is_member && has_key,
         share_listens: rec.share_listens,
+        share_holdings: rec.share_holdings,
         has_key,
         reachable,
     }
@@ -563,6 +572,7 @@ pub async fn create(app: &tauri::AppHandle, name: &str, description: &str, priva
         roster: BTreeMap::new(),
         invited: BTreeMap::new(),
         share_listens: false,
+        share_holdings: false,
         last_listen: None,
         join_sent_at: 0,
     };
@@ -826,6 +836,53 @@ pub async fn set_pinned(app: &tauri::AppHandle, owner_b58: &str, space_b58: &str
 
 /// Turn posting-what-I-play on or off for one Space. Nothing is published
 /// by flipping it; it only decides what the next track does.
+/// What `holdings.rs` needs to know about a room, without the record.
+pub(crate) struct RoomFacts {
+    pub name: String,
+    pub private: bool,
+    pub my_role: String,
+    pub share_holdings: bool,
+}
+
+pub(crate) fn room_facts(app: &tauri::AppHandle, owner_b58: &str, space_b58: &str) -> Option<RoomFacts> {
+    let l = load(app);
+    let rec = l.spaces.get(&record_id(owner_b58, space_b58))?;
+    Some(RoomFacts { name: rec.name.clone(), private: rec.private, my_role: rec.my_role.clone(), share_holdings: rec.share_holdings })
+}
+
+/// The room's key for one epoch, if this device was handed it.
+pub(crate) fn epoch_key_for(app: &tauri::AppHandle, owner_b58: &str, space_b58: &str, epoch: u64) -> Option<[u8; 32]> {
+    let l = load(app);
+    let rec = l.spaces.get(&record_id(owner_b58, space_b58))?;
+    rec.keys.get(&epoch.to_string()).and_then(|k| key_of(k).ok())
+}
+
+/// Every room this device is in: (owner, space id, name).
+pub(crate) fn rooms(app: &tauri::AppHandle) -> Vec<(String, String, String)> {
+    load(app).spaces.values().map(|r| (r.owner.clone(), r.space_id.clone(), r.name.clone())).collect()
+}
+
+/// The rooms this device publishes its holdings into.
+pub(crate) fn rooms_sharing_holdings(app: &tauri::AppHandle) -> Vec<(String, String)> {
+    load(app).spaces.values().filter(|r| r.share_holdings).map(|r| (r.owner.clone(), r.space_id.clone())).collect()
+}
+
+/// The Soulseek name behind a room key as this device knows it: through the
+/// owner's private roster, or the key itself when it is a persona (an owner's).
+pub(crate) fn username_behind(app: &tauri::AppHandle, owner_b58: &str, space_b58: &str, member_b58: &str) -> Option<String> {
+    let l = load(app);
+    let rec = l.spaces.get(&record_id(owner_b58, space_b58))?;
+    slsk_link::username_for_key(app, rec.roster.get(member_b58).map(String::as_str).unwrap_or(member_b58))
+}
+
+pub(crate) async fn set_share_holdings_flag(app: &tauri::AppHandle, owner_b58: &str, space_b58: &str, on: bool) -> Result<(), String> {
+    let _ledger = ledger::hold(LEDGER_FILE).await;
+    let mut l = load(app);
+    let rec = l.spaces.get_mut(&record_id(owner_b58, space_b58)).ok_or("not a Space this device knows")?;
+    rec.share_holdings = on;
+    save(app, &l)
+}
+
 pub async fn set_share_listens(app: &tauri::AppHandle, owner_b58: &str, space_b58: &str, on: bool) -> Result<SpaceView, String> {
     {
         let _ledger = ledger::hold(LEDGER_FILE).await;
@@ -946,6 +1003,7 @@ pub(crate) async fn on_inbox_invite(app: &tauri::AppHandle, sender: [u8; 32], in
             roster: BTreeMap::new(),
             invited: BTreeMap::new(),
             share_listens: false,
+        share_holdings: false,
             last_listen: None,
             join_sent_at: 0,
         });
@@ -1197,6 +1255,7 @@ mod tests {
             roster: BTreeMap::new(),
             invited: BTreeMap::new(),
             share_listens: false,
+        share_holdings: false,
             last_listen: None,
             join_sent_at: 0,
         }