From 4dddd3607374d8988a7653adff1b4c50147e19e1 Mon Sep 17 00:00:00 2001
From: vicrodh <103399283+vicrodh@users.noreply.github.com>
Date: Wed, 27 May 2026 08:03:56 -0600
Subject: [PATCH] feat(slint): per-context genre filter + favorites genre
 filtering

Make genre_filter.rs selection per-context (HashMap keyed by "discover" /
"favorites" + a current context the popup edits), so favorites filters
independently from Discover. Discover keeps its server-side path
unchanged (reads filter_ids("discover") explicitly; its genre buttons set
the "discover" context on open). Favorites get a genre button in both
toolbars that opens the shared popup in the "favorites" context, plus the
popup overlay; derive_tracks / derive_albums filter client-side by the
selected genre NAMES (selected_names expands parents to descendants).
on_toggle / on_clear branch on the current context to re-derive favorites
instead of re-fetching Discover. AlbumSummary gains an optional `genre`
(favorites track album objects carry it; TrackItem can't, so a track
id->genre map backs the tracks filter). Persisted per-context (legacy
flat selection migrates to "discover").

cc
---
 crates/qbz-models/src/types.rs                |   2 +
 crates/qbz-slint/src/favorites.rs             |  63 +++++-
 crates/qbz-slint/src/genre_filter.rs          | 203 ++++++++++++------
 crates/qbz-slint/src/main.rs                  |  56 ++++-
 .../ui/discover/DiscoverBrowseView.slint      |   3 +-
 crates/qbz-slint/ui/discover/HomeView.slint   |   3 +-
 .../ui/favorites/FavoritesView.slint          |  70 ++++++
 crates/qbz-slint/ui/state.slint               |   3 +
 8 files changed, 327 insertions(+), 76 deletions(-)

diff --git a/crates/qbz-models/src/types.rs b/crates/qbz-models/src/types.rs
index 4643b036d..d42a67660 100644
--- a/crates/qbz-models/src/types.rs
+++ b/crates/qbz-models/src/types.rs
@@ -248,6 +248,8 @@ pub struct AlbumSummary {
     pub image: ImageSet,
     /// Label (if returned in track response)
     pub label: Option<Label>,
+    /// Genre (when returned, e.g. on favorites track album objects).
+    pub genre: Option<Genre>,
 }
 
 /// Album model
diff --git a/crates/qbz-slint/src/favorites.rs b/crates/qbz-slint/src/favorites.rs
index 303cfa0ab..5fa86e74c 100644
--- a/crates/qbz-slint/src/favorites.rs
+++ b/crates/qbz-slint/src/favorites.rs
@@ -8,6 +8,7 @@
 //! relevant branch into typed qbz-models items and maps them to the
 //! Slint row/card structs.
 
+use std::cell::RefCell;
 use std::collections::HashMap;
 use std::sync::{Arc, LazyLock, Mutex};
 
@@ -37,6 +38,12 @@ const MAX_ITEMS: usize = 10_000;
 /// Shuffle). Set on the UI thread by `apply_favorites`.
 static FAV_CURRENT: LazyLock<Mutex<Vec<Track>>> = LazyLock::new(|| Mutex::new(Vec::new()));
 
+thread_local! {
+    /// Track id -> genre name, for the favorites Tracks genre filter
+    /// (TrackItem carries no genre). Set on the UI thread by apply.
+    static FAV_TRACK_GENRE: RefCell<HashMap<String, String>> = RefCell::new(HashMap::new());
+}
+
 /// Which favorites tab to load.
 #[derive(Clone, Copy, PartialEq, Eq)]
 pub enum FavTab {
@@ -105,6 +112,7 @@ pub struct TrackCard {
     pub artist_id: String,
     pub album: String,
     pub album_id: String,
+    pub genre: String,
     pub duration: String,
     pub quality_tier: String,
     pub explicit: bool,
@@ -248,6 +256,12 @@ fn map_track(track: Track) -> TrackCard {
         .map(|a| a.title.clone())
         .unwrap_or_default();
     let album_id = track.album.as_ref().map(|a| a.id.clone()).unwrap_or_default();
+    let genre = track
+        .album
+        .as_ref()
+        .and_then(|a| a.genre.as_ref())
+        .map(|g| g.name.clone())
+        .unwrap_or_default();
     let (artist, artist_id) = track
         .performer
         .map(|p| (p.name, p.id.to_string()))
@@ -259,6 +273,7 @@ fn map_track(track: Track) -> TrackCard {
         artist_id,
         album,
         album_id,
+        genre,
         duration: mmss(track.duration),
         quality_tier: album_map::tier(track.maximum_bit_depth).to_string(),
         explicit: track.parental_warning,
@@ -319,6 +334,9 @@ pub fn apply_favorites(window: &AppWindow, data: FavData) {
             if let Ok(mut current) = FAV_CURRENT.lock() {
                 *current = play;
             }
+            FAV_TRACK_GENRE.with(|m| {
+                *m.borrow_mut() = items.iter().map(|t| (t.id.clone(), t.genre.clone())).collect();
+            });
             let rows: Vec<TrackItem> = items
                 .into_iter()
                 .map(|t| TrackItem {
@@ -428,19 +446,21 @@ pub fn derive_tracks(window: &AppWindow) {
     let query_owned = state.get_tracks_search().to_lowercase();
     let query = query_owned.trim();
     let group = state.get_tracks_group_mode().to_string();
+    let genre_names = crate::genre_filter::selected_names("favorites");
     let all = state.get_tracks();
-    // Fast path: no search + no grouping -> share full model (artwork live).
-    if query.is_empty() && group == "off" {
+    // Fast path: no search + no grouping + no genre filter -> share model.
+    if query.is_empty() && group == "off" && genre_names.is_empty() {
         state.set_tracks_visible(all);
         return;
     }
     let mut filtered: Vec<TrackItem> = (0..all.row_count())
         .filter_map(|i| all.row_data(i))
         .filter(|t| {
-            query.is_empty()
+            (query.is_empty()
                 || t.title.to_lowercase().contains(query)
                 || t.artist.to_lowercase().contains(query)
-                || t.album.to_lowercase().contains(query)
+                || t.album.to_lowercase().contains(query))
+                && track_genre_matches(t.id.as_str(), &genre_names)
         })
         .collect();
     // Group-by reorders the rows so a group's tracks sit together (Tauri
@@ -497,11 +517,12 @@ pub fn derive_albums(window: &AppWindow) {
     let query = query_owned.trim();
     let sort = state.get_albums_sort_by().to_string();
     let group = state.get_albums_group_mode().to_string();
+    let genre_names = crate::genre_filter::selected_names("favorites");
     let all = state.get_albums();
     let empty_sections = || ModelRc::new(VecModel::from(Vec::<DiscoverSection>::new()));
 
-    // Fast path: no filter, default order, no grouping -> share full model.
-    if query.is_empty() && sort == "default" && group == "off" {
+    // Fast path: no filter, default order, no grouping, no genre -> share.
+    if query.is_empty() && sort == "default" && group == "off" && genre_names.is_empty() {
         let n = all.row_count() as i32;
         state.set_albums_visible(all);
         state.set_albums_grouped(empty_sections());
@@ -512,9 +533,10 @@ pub fn derive_albums(window: &AppWindow) {
     let mut filtered: Vec<AlbumCardItem> = (0..all.row_count())
         .filter_map(|i| all.row_data(i))
         .filter(|a| {
-            query.is_empty()
+            (query.is_empty()
                 || a.title.to_lowercase().contains(query)
-                || a.artist.to_lowercase().contains(query)
+                || a.artist.to_lowercase().contains(query))
+                && album_genre_matches(a.genre.as_str(), &genre_names)
         })
         .collect();
     album_map::sort_album_items(&mut filtered, &sort);
@@ -573,6 +595,31 @@ fn album_alpha_key(title: &str) -> String {
     }
 }
 
+/// True if `genre` matches any selected genre name (favorites filter).
+fn album_genre_matches(genre: &str, names: &[String]) -> bool {
+    if names.is_empty() {
+        return true;
+    }
+    let g = genre.to_lowercase();
+    names.iter().any(|n| g.contains(&n.to_lowercase()))
+}
+
+/// Same, looking the track's genre up in the id->genre map.
+fn track_genre_matches(id: &str, names: &[String]) -> bool {
+    if names.is_empty() {
+        return true;
+    }
+    FAV_TRACK_GENRE.with(|m| {
+        m.borrow()
+            .get(id)
+            .map(|g| {
+                let gl = g.to_lowercase();
+                names.iter().any(|n| gl.contains(&n.to_lowercase()))
+            })
+            .unwrap_or(false)
+    })
+}
+
 /// A random album id from the currently-visible set (Shuffle / random).
 pub fn random_visible_album(window: &AppWindow) -> Option<String> {
     let model = window.global::<FavoritesState>().get_albums_visible();
diff --git a/crates/qbz-slint/src/genre_filter.rs b/crates/qbz-slint/src/genre_filter.rs
index 98b5524e7..76a560697 100644
--- a/crates/qbz-slint/src/genre_filter.rs
+++ b/crates/qbz-slint/src/genre_filter.rs
@@ -1,11 +1,13 @@
 //! Filter-by-genre controller.
 //!
-//! Loads the parent genres for the Discover popup's simple grid and
-//! owns the shared genre selection (one set for all three Discover
-//! tabs, matching Tauri's single "home" genre context). The selection
+//! Loads the parent genres for the popup's simple grid and owns the genre
+//! selection. The selection is **per context** ("discover" for the three
+//! Discover tabs, "favorites" for the favorites tabs) so the two surfaces
+//! filter independently (Tauri keeps them separate too). The popup edits
+//! whatever context is `current` (set when it opens). The selection
 //! persists to `<data-dir>/qbz/genre_filter.json` when "Remember
-//! selection" is on, and feeds `genre_ids` into the discover-index
-//! fetch.
+//! selection" is on, and feeds `genre_ids` into the discover-index fetch /
+//! the favorites client-side genre filter.
 
 use std::collections::{HashMap, HashSet};
 use std::path::PathBuf;
@@ -26,6 +28,10 @@ struct GenreItem {
 
 #[derive(Default, Serialize, Deserialize)]
 struct Persisted {
+    /// Per-context selections ("discover" / "favorites" / ...).
+    #[serde(default)]
+    contexts: HashMap<String, Vec<u64>>,
+    /// Legacy single-list selection — migrated into the "discover" context.
     #[serde(default)]
     selected: Vec<u64>,
     #[serde(default = "default_true")]
@@ -40,17 +46,41 @@ struct State {
     parents: Vec<GenreItem>,
     /// Lazily loaded children, keyed by parent id (levels 2 and 3).
     children: HashMap<u64, Vec<GenreItem>>,
-    selected: Vec<u64>,
+    /// Selected genre ids per context.
+    selected: HashMap<String, Vec<u64>>,
+    /// The context the popup is currently editing.
+    current: String,
     expanded: HashSet<u64>,
     search: String,
     remember: bool,
 }
 
+impl State {
+    /// Mutable handle to the current context's selection (created if absent).
+    fn cur_mut(&mut self) -> &mut Vec<u64> {
+        let key = self.current.clone();
+        self.selected.entry(key).or_default()
+    }
+    fn is_selected(&self, id: u64) -> bool {
+        self.selected
+            .get(&self.current)
+            .map(|v| v.contains(&id))
+            .unwrap_or(false)
+    }
+    fn cur_len(&self) -> usize {
+        self.selected
+            .get(&self.current)
+            .map(|v| v.len())
+            .unwrap_or(0)
+    }
+}
+
 static STATE: LazyLock<Mutex<State>> = LazyLock::new(|| {
     Mutex::new(State {
         parents: Vec::new(),
         children: HashMap::new(),
-        selected: Vec::new(),
+        selected: HashMap::new(),
+        current: "discover".to_string(),
         expanded: HashSet::new(),
         search: String::new(),
         remember: true,
@@ -71,7 +101,7 @@ fn load_persisted() -> Persisted {
     }
 }
 
-fn save_persisted(selected: &[u64], remember: bool) {
+fn save_persisted(contexts: &HashMap<String, Vec<u64>>, remember: bool) {
     let Some(path) = store_path() else {
         return;
     };
@@ -84,7 +114,8 @@ fn save_persisted(selected: &[u64], remember: bool) {
         let _ = std::fs::create_dir_all(parent);
     }
     let data = Persisted {
-        selected: selected.to_vec(),
+        contexts: contexts.clone(),
+        selected: Vec::new(),
         remember,
     };
     if let Ok(json) = serde_json::to_vec_pretty(&data) {
@@ -92,29 +123,71 @@ fn save_persisted(selected: &[u64], remember: bool) {
     }
 }
 
-/// The explicitly-selected genre ids (what the user clicked).
-pub fn selected_ids() -> Vec<u64> {
-    STATE.lock().map(|s| s.selected.clone()).unwrap_or_default()
+/// Set the context the popup edits (call when opening it for a surface).
+pub fn set_context(ctx: &str) {
+    if let Ok(mut s) = STATE.lock() {
+        s.current = ctx.to_string();
+        s.selected.entry(ctx.to_string()).or_default();
+    }
 }
 
-/// The ids to actually filter by: the selection plus every loaded
-/// descendant of each selected genre. Selecting a parent therefore
-/// covers its children/grandchildren — restoring the child-genre
-/// filtering the discovery-v2 home redesign dropped (the old home
-/// expanded to descendant names client-side; here we expand to
-/// descendant ids for the server filter).
-pub fn filter_ids() -> Vec<u64> {
+/// The context the popup is currently editing.
+pub fn current_context() -> String {
+    STATE
+        .lock()
+        .map(|s| s.current.clone())
+        .unwrap_or_else(|_| "discover".to_string())
+}
+
+/// The explicitly-selected genre ids in the current popup context.
+pub fn selected_ids() -> Vec<u64> {
+    STATE
+        .lock()
+        .map(|s| s.selected.get(&s.current).cloned().unwrap_or_default())
+        .unwrap_or_default()
+}
+
+/// The ids to filter by for `ctx`: its selection plus every loaded
+/// descendant of each selected genre (selecting a parent covers its
+/// children). Server-side genre filter for Discover.
+pub fn filter_ids(ctx: &str) -> Vec<u64> {
     let Ok(s) = STATE.lock() else {
         return Vec::new();
     };
     let mut out: HashSet<u64> = HashSet::new();
-    for id in &s.selected {
-        out.insert(*id);
-        collect_descendants(&s.children, *id, &mut out);
+    if let Some(sel) = s.selected.get(ctx) {
+        for id in sel {
+            out.insert(*id);
+            collect_descendants(&s.children, *id, &mut out);
+        }
     }
     out.into_iter().collect()
 }
 
+/// Selected genre NAMES (+ descendant names) for `ctx` — for the
+/// client-side album / track genre filter used by favorites.
+pub fn selected_names(ctx: &str) -> Vec<String> {
+    let Ok(s) = STATE.lock() else {
+        return Vec::new();
+    };
+    let mut ids: HashSet<u64> = HashSet::new();
+    if let Some(sel) = s.selected.get(ctx) {
+        for id in sel {
+            ids.insert(*id);
+            collect_descendants(&s.children, *id, &mut ids);
+        }
+    }
+    let mut names: Vec<String> = Vec::new();
+    for id in ids {
+        if let Some(g) = s.parents.iter().find(|g| g.id == id) {
+            names.push(g.name.clone());
+        } else if let Some(g) = s.children.values().flatten().find(|g| g.id == id) {
+            names.push(g.name.clone());
+        }
+    }
+    names
+}
+
 fn collect_descendants(
     children: &HashMap<u64, Vec<GenreItem>>,
     id: u64,
@@ -139,9 +212,9 @@ fn store_children(parent_id: u64, kids: Vec<GenreItem>) {
     }
 }
 
-/// Fetch the parent genres (if not already loaded) and seed the
-/// persisted selection. Runs on a worker; call apply_state afterwards
-/// on the UI thread.
+/// Fetch the parent genres (if not already loaded) and seed the persisted
+/// selection. Runs on a worker; call apply_state afterwards on the UI
+/// thread.
 pub async fn load_parents<A>(runtime: &AppRuntime<A>)
 where
     A: FrontendAdapter + Send + Sync + 'static,
@@ -168,18 +241,23 @@ where
     };
     parents.sort_by(|a, b| a.name.to_lowercase().cmp(&b.name.to_lowercase()));
 
-    // Keep persisted selections as-is — they may reference child
-    // genres not yet loaded (advanced view), so validating against
-    // parents only would wrongly drop them.
+    // Keep persisted selections as-is — they may reference child genres
+    // not yet loaded (advanced view), so validating against parents only
+    // would wrongly drop them.
     if let Ok(mut s) = STATE.lock() {
         s.parents = parents;
-        s.selected = persisted.selected;
+        let mut contexts = persisted.contexts;
+        // Migrate a legacy flat selection into the discover context.
+        if contexts.is_empty() && !persisted.selected.is_empty() {
+            contexts.insert("discover".to_string(), persisted.selected);
+        }
+        s.selected = contexts;
         s.remember = persisted.remember;
     }
 }
 
-/// Load one genre level (children of `parent_id`) and store it. No-op
-/// if already loaded.
+/// Load one genre level (children of `parent_id`) and store it. No-op if
+/// already loaded.
 pub async fn load_children<A>(runtime: &AppRuntime<A>, parent_id: u64)
 where
     A: FrontendAdapter + Send + Sync + 'static,
@@ -208,8 +286,8 @@ fn child_ids(parent_id: u64) -> Vec<u64> {
         .unwrap_or_default()
 }
 
-/// Eager-load every parent's children (level 2) so the advanced tree
-/// can show child counts up front. Grandchildren stay lazy.
+/// Eager-load every parent's children (level 2) so the advanced tree can
+/// show child counts up front. Grandchildren stay lazy.
 pub async fn load_all_parent_children<A>(runtime: &AppRuntime<A>)
 where
     A: FrontendAdapter + Send + Sync + 'static,
@@ -223,8 +301,8 @@ where
     }
 }
 
-/// Eager-load a genre's full descendant subtree (children +
-/// grandchildren), so a selection expands correctly in filter_ids.
+/// Eager-load a genre's full descendant subtree (children + grandchildren),
+/// so a selection expands correctly in filter_ids / selected_names.
 pub async fn load_descendants<A>(runtime: &AppRuntime<A>, id: u64)
 where
     A: FrontendAdapter + Send + Sync + 'static,
@@ -235,8 +313,8 @@ where
     }
 }
 
-/// Toggle a tree node's expanded state. Returns true if it is now
-/// expanded (so the caller can lazy-load its children).
+/// Toggle a tree node's expanded state. Returns true if it is now expanded
+/// (so the caller can lazy-load its children).
 pub fn toggle_expand(id_str: &str) -> bool {
     let Ok(id) = id_str.parse::<u64>() else {
         return false;
@@ -259,8 +337,8 @@ pub fn set_search(query: &str) {
     }
 }
 
-/// Push the current parents + selection + tree into GenreFilterState.
-/// UI thread.
+/// Push the current parents + selection + tree into GenreFilterState (for
+/// the current context). UI thread.
 pub fn apply_state(window: &AppWindow) {
     let (chips, rows, count, remember) = {
         let Ok(s) = STATE.lock() else {
@@ -272,10 +350,10 @@ pub fn apply_state(window: &AppWindow) {
             .map(|g| GenreChip {
                 id: g.id.to_string().into(),
                 name: g.name.clone().into(),
-                selected: s.selected.contains(&g.id),
+                selected: s.is_selected(g.id),
             })
             .collect();
-        (chips, build_tree_rows(&s), s.selected.len() as i32, s.remember)
+        (chips, build_tree_rows(&s), s.cur_len() as i32, s.remember)
     };
     let state = window.global::<GenreFilterState>();
     state.set_genres(ModelRc::new(VecModel::from(chips)));
@@ -287,8 +365,8 @@ pub fn apply_state(window: &AppWindow) {
 fn tree_row(item: &GenreItem, level: i32, s: &State) -> GenreTreeRow {
     let loaded = s.children.get(&item.id);
     let count = loaded.map(|c| c.len()).unwrap_or(0);
-    // Parents always have children; deeper levels show an expand
-    // arrow optimistically until a load proves them empty.
+    // Parents always have children; deeper levels show an expand arrow
+    // optimistically until a load proves them empty.
     let has_children = if level == 0 {
         true
     } else if level == 1 {
@@ -300,17 +378,17 @@ fn tree_row(item: &GenreItem, level: i32, s: &State) -> GenreTreeRow {
         id: item.id.to_string().into(),
         name: item.name.clone().into(),
         level,
-        selected: s.selected.contains(&item.id),
+        selected: s.is_selected(item.id),
         expanded: s.expanded.contains(&item.id),
         has_children,
         count: count as i32,
     }
 }
 
-/// Flatten the genre tree into the currently-visible rows. With a
-/// search query, returns a flat list of all loaded genres matching
-/// the query (ignoring expansion); otherwise honors per-node
-/// expansion down three levels.
+/// Flatten the genre tree into the currently-visible rows. With a search
+/// query, returns a flat list of all loaded genres matching the query
+/// (ignoring expansion); otherwise honors per-node expansion down three
+/// levels.
 fn build_tree_rows(s: &State) -> Vec<GenreTreeRow> {
     let query = s.search.trim().to_lowercase();
     let mut rows: Vec<GenreTreeRow> = Vec::new();
@@ -355,8 +433,8 @@ fn build_tree_rows(s: &State) -> Vec<GenreTreeRow> {
     rows
 }
 
-/// Toggle a genre id in the selection. Returns true if the selection
-/// changed (so the caller can re-fetch).
+/// Toggle a genre id in the current context's selection. Returns true if
+/// the selection changed (so the caller can re-fetch / re-derive).
 pub fn toggle(id_str: &str) -> bool {
     let Ok(id) = id_str.parse::<u64>() else {
         return false;
@@ -364,14 +442,17 @@ pub fn toggle(id_str: &str) -> bool {
     let Ok(mut s) = STATE.lock() else {
         return false;
     };
-    if let Some(pos) = s.selected.iter().position(|x| *x == id) {
-        s.selected.remove(pos);
-    } else {
-        s.selected.push(id);
+    {
+        let sel = s.cur_mut();
+        if let Some(pos) = sel.iter().position(|x| *x == id) {
+            sel.remove(pos);
+        } else {
+            sel.push(id);
+        }
     }
-    let (sel, rem) = (s.selected.clone(), s.remember);
+    let (contexts, rem) = (s.selected.clone(), s.remember);
     drop(s);
-    save_persisted(&sel, rem);
+    save_persisted(&contexts, rem);
     true
 }
 
@@ -379,10 +460,10 @@ pub fn clear() {
     let Ok(mut s) = STATE.lock() else {
         return;
     };
-    s.selected.clear();
-    let rem = s.remember;
+    s.cur_mut().clear();
+    let (contexts, rem) = (s.selected.clone(), s.remember);
     drop(s);
-    save_persisted(&[], rem);
+    save_persisted(&contexts, rem);
 }
 
 pub fn set_remember(remember: bool) {
@@ -390,7 +471,7 @@ pub fn set_remember(remember: bool) {
         return;
     };
     s.remember = remember;
-    let sel = s.selected.clone();
+    let contexts = s.selected.clone();
     drop(s);
-    save_persisted(&sel, remember);
+    save_persisted(&contexts, remember);
 }
diff --git a/crates/qbz-slint/src/main.rs b/crates/qbz-slint/src/main.rs
index 63ebb4ea4..eb6ec5bcf 100644
--- a/crates/qbz-slint/src/main.rs
+++ b/crates/qbz-slint/src/main.rs
@@ -143,7 +143,7 @@ async fn enter_shell(
 /// `Option<Vec<u64>>` the discover endpoints take (None = no filter).
 /// Shared by the home re-fetch and the DiscoverBrowse "View all" page.
 fn current_genre_filter() -> Option<Vec<u64>> {
-    let ids = genre_filter::filter_ids();
+    let ids = genre_filter::filter_ids("discover");
     (!ids.is_empty()).then_some(ids)
 }
 
@@ -159,7 +159,7 @@ async fn reload_home(
 ) {
     // Expand the selection to descendants so a parent selection
     // covers its child genres (the child-genre filtering recovery).
-    let genre_ids = genre_filter::filter_ids();
+    let genre_ids = genre_filter::filter_ids("discover");
     let genre_ids = (!genre_ids.is_empty()).then_some(genre_ids);
 
     match home::load_home(runtime, genre_ids).await {
@@ -780,6 +780,10 @@ fn navigate_favorites(
             state.set_active_tab(tab_id_for_ui.into());
             favorites::reset_loading(&w);
             w.global::<NavState>().set_view(ContentView::Favorites);
+            // The genre popup edits the favorites context here, and the
+            // toolbar genre button shows the favorites selection count.
+            genre_filter::set_context("favorites");
+            genre_filter::apply_state(&w);
         });
         match favorites::load_favorites(&runtime, tab).await {
             Ok(data) => {
@@ -3233,9 +3237,20 @@ fn main() -> Result<(), Box<dyn std::error::Error>> {
             });
     }
 
-    // Genre filter — shared selection across the three Discover tabs.
-    // Toggling / clearing re-fetches the discover index with the new
-    // genre ids and rebuilds the section sets; the active tab stays.
+    // Genre filter — selection is per context ("discover" / "favorites").
+    // Toggling / clearing re-fetches the discover index (discover context)
+    // or re-derives the favorites tab (favorites context).
+    {
+        let weak = window.as_weak();
+        window
+            .global::<GenreFilterActions>()
+            .on_set_context(move |ctx| {
+                genre_filter::set_context(ctx.as_str());
+                if let Some(w) = weak.upgrade() {
+                    genre_filter::apply_state(&w);
+                }
+            });
+    }
     {
         let runtime = app_runtime.clone();
         let weak = window.as_weak();
@@ -3254,6 +3269,29 @@ fn main() -> Result<(), Box<dyn std::error::Error>> {
                     return;
                 };
                 genre_filter::apply_state(&w);
+                // Favorites: client-side genre filter — re-derive the active
+                // favorites tab instead of re-fetching the discover index.
+                if genre_filter::current_context() == "favorites" {
+                    let runtime_f = runtime.clone();
+                    let weak_f = weak.clone();
+                    let id_f = id.to_string();
+                    handle.spawn(async move {
+                        if !was_selected {
+                            if let Ok(gid) = id_f.parse::<u64>() {
+                                genre_filter::load_descendants(&runtime_f, gid).await;
+                            }
+                        }
+                        let _ = weak_f.upgrade_in_event_loop(|w| {
+                            genre_filter::apply_state(&w);
+                            if w.global::<FavoritesState>().get_active_tab().as_str() == "albums" {
+                                favorites::derive_albums(&w);
+                            } else {
+                                favorites::derive_tracks(&w);
+                            }
+                        });
+                    });
+                    return;
+                }
                 // When the DiscoverBrowse "View all" page is showing, the
                 // genre change re-fetches THAT page; otherwise it reloads
                 // the Discover home index.
@@ -3347,6 +3385,14 @@ fn main() -> Result<(), Box<dyn std::error::Error>> {
                     return;
                 };
                 genre_filter::apply_state(&w);
+                if genre_filter::current_context() == "favorites" {
+                    if w.global::<FavoritesState>().get_active_tab().as_str() == "albums" {
+                        favorites::derive_albums(&w);
+                    } else {
+                        favorites::derive_tracks(&w);
+                    }
+                    return;
+                }
                 let browse_target = current_browse_target(&w);
                 if browse_target.is_none() {
                     w.global::<HomeState>().set_loading(true);
diff --git a/crates/qbz-slint/ui/discover/DiscoverBrowseView.slint b/crates/qbz-slint/ui/discover/DiscoverBrowseView.slint
index ccbc4b93c..293288e3e 100644
--- a/crates/qbz-slint/ui/discover/DiscoverBrowseView.slint
+++ b/crates/qbz-slint/ui/discover/DiscoverBrowseView.slint
@@ -10,7 +10,7 @@
 
 import { Theme } from "../foundation/semantic-colors.slint";
 import { Typography } from "../foundation/typography.slint";
-import { DiscoverBrowseState, DiscoverBrowseActions, GenreFilterState } from "../state.slint";
+import { DiscoverBrowseState, DiscoverBrowseActions, GenreFilterState, GenreFilterActions } from "../state.slint";
 import { AlbumCollectionView } from "AlbumCollectionView.slint";
 import { GenreFilterPopup } from "GenreFilterPopup.slint";
 import { LoadingSpinner } from "../primitives/LoadingSpinner.slint";
@@ -209,6 +209,7 @@ export component DiscoverBrowseView inherits Rectangle {
                     alignment: center;
                     GenreButton {
                         clicked => {
+                            GenreFilterActions.set-context("discover");
                             GenreFilterState.open = !GenreFilterState.open;
                         }
                     }
diff --git a/crates/qbz-slint/ui/discover/HomeView.slint b/crates/qbz-slint/ui/discover/HomeView.slint
index 19a9658ab..a930708aa 100644
--- a/crates/qbz-slint/ui/discover/HomeView.slint
+++ b/crates/qbz-slint/ui/discover/HomeView.slint
@@ -8,7 +8,7 @@
 
 import { Theme } from "../foundation/semantic-colors.slint";
 import { Typography } from "../foundation/typography.slint";
-import { HomeState, HomeActions, GenreFilterState, NavState, ContentView } from "../state.slint";
+import { HomeState, HomeActions, GenreFilterState, GenreFilterActions, NavState, ContentView } from "../state.slint";
 import { Carousel } from "Carousel.slint";
 import { SlimCarousel } from "SlimCarousel.slint";
 import { HomeSkeleton } from "HomeSkeleton.slint";
@@ -225,6 +225,7 @@ export component HomeView inherits Rectangle {
                 spacing: 6px;
                 GenreButton {
                     clicked => {
+                        GenreFilterActions.set-context("discover");
                         GenreFilterState.open = !GenreFilterState.open;
                     }
                 }
diff --git a/crates/qbz-slint/ui/favorites/FavoritesView.slint b/crates/qbz-slint/ui/favorites/FavoritesView.slint
index cafc906c0..272b7ee01 100644
--- a/crates/qbz-slint/ui/favorites/FavoritesView.slint
+++ b/crates/qbz-slint/ui/favorites/FavoritesView.slint
@@ -17,8 +17,11 @@ import {
     FavoritePlaylistItem,
     FavoriteLabelItem,
     DragState,
+    GenreFilterState,
+    GenreFilterActions,
 } from "../state.slint";
 import { AlbumCollectionView } from "../discover/AlbumCollectionView.slint";
+import { GenreFilterPopup } from "../discover/GenreFilterPopup.slint";
 import { TrackRow } from "../primitives/TrackRow.slint";
 import { ExpandableSearch } from "../primitives/ExpandableSearch.slint";
 import { CircleAction } from "../primitives/CircleAction.slint";
@@ -242,6 +245,50 @@ component FavArtistCard inherits Rectangle {
     }
 }
 
+// Genre-filter trigger for the favorites toolbars — opens the shared
+// popup in the "favorites" context. Accent fill + "N genres" when active.
+component FavGenreButton inherits Rectangle {
+    property <bool> active: GenreFilterState.selected-count > 0;
+    width: genre-row.preferred-width;
+    height: 34px;
+    border-radius: 6px;
+    background: root.active
+        ? Theme.accent
+        : (ta.has-hover ? Theme.surface-hover : Theme.surface-elevated);
+
+    genre-row := HorizontalLayout {
+        padding-left: 12px;
+        padding-right: 14px;
+        spacing: 7px;
+        VerticalLayout {
+            alignment: center;
+            QbzIcon {
+                source: @image-url("../assets/icons/list-filter.svg");
+                width: 14px;
+                height: 14px;
+                tint: root.active ? #ffffff : Theme.text-secondary;
+            }
+        }
+        Text {
+            text: root.active
+                ? (GenreFilterState.selected-count == 1
+                    ? @tr("1 genre")
+                    : @tr("{} genres", GenreFilterState.selected-count))
+                : @tr("Filter by genre");
+            color: root.active ? #ffffff : Theme.text-secondary;
+            font-size: 13px;
+            vertical-alignment: center;
+        }
+    }
+    ta := TouchArea {
+        mouse-cursor: pointer;
+        clicked => {
+            GenreFilterActions.set-context("favorites");
+            GenreFilterState.open = !GenreFilterState.open;
+        }
+    }
+}
+
 export component FavoritesView inherits Rectangle {
     callback open-album(string);
     callback open-artist(string);
@@ -464,6 +511,10 @@ export component FavoritesView inherits Rectangle {
                             }
                         }
                     }
+                    VerticalLayout {
+                        alignment: center;
+                        FavGenreButton { }
+                    }
                     VerticalLayout {
                         alignment: center;
                         QbzSelect {
@@ -572,6 +623,10 @@ export component FavoritesView inherits Rectangle {
                             }
                         }
                     }
+                    VerticalLayout {
+                        alignment: center;
+                        FavGenreButton { }
+                    }
                     VerticalLayout {
                         alignment: center;
                         QbzSelect {
@@ -752,4 +807,19 @@ export component FavoritesView inherits Rectangle {
         visible-height: flick.height;
         viewport-y <=> flick.viewport-y;
     }
+
+    // Genre filter overlay — the shared popup, favorites context.
+    if GenreFilterState.open: Rectangle {
+        width: 100%;
+        height: 100%;
+        TouchArea {
+            clicked => {
+                GenreFilterState.open = false;
+            }
+        }
+    }
+    if GenreFilterState.open: GenreFilterPopup {
+        x: root.width - self.width - 32px;
+        y: 56px;
+    }
 }
diff --git a/crates/qbz-slint/ui/state.slint b/crates/qbz-slint/ui/state.slint
index 711e44eff..c9baa22e9 100644
--- a/crates/qbz-slint/ui/state.slint
+++ b/crates/qbz-slint/ui/state.slint
@@ -203,6 +203,9 @@ export global GenreFilterState {
 }
 
 export global GenreFilterActions {
+    // Set the context the popup edits ("discover" | "favorites"), called
+    // when a surface opens the shared popup.
+    callback set-context(string);
     callback toggle(string /* genre id */);
     callback toggle-expand(string /* genre id */);
     callback search(string /* query */);