feat(qbz-slint): album detail page

Clicking an album card opens the album detail view: a back button,
the album header (224px artwork, title, artist, and info line — year,
label, genre, track count, duration — plus play / shuffle / favorite /
more action buttons), and the track list with a column header (#,
title, artist, duration, quality).

- album.rs: fetches the album via QbzCore::get_album, maps it (info
  line, per-track quality tier, durations) onto the AlbumState global,
  and loads the header artwork through the shared image cache.
- AlbumPageView.slint, with NavState driving the shell content region
  between Home and the album page.
- Album clicks bubble AlbumCard -> Carousel -> HomeView -> AppShell ->
  AppWindow -> main; the back button returns to Home.

cc

crates/qbz-slint/src/album.rs

@@ -0,0 +1,205 @@
+//! Album detail controller.
+//!
+//! Fetches a full album through `QbzCore`, maps it to plain (Send) data
+//! on the worker thread, and applies it to the `AlbumState` global on the
+//! Slint event loop.
+
+use std::sync::Arc;
+
+use qbz_app::shell::AppRuntime;
+use qbz_core::FrontendAdapter;
+use qbz_models::{Album, Track};
+use slint::{ComponentHandle, ModelRc, VecModel};
+
+use crate::{AlbumState, AlbumTrackItem, AppWindow};
+
+/// Plain, `Send` album data produced on the worker thread.
+pub struct AlbumData {
+    pub title: String,
+    pub artist: String,
+    /// Pre-formatted "year • label • genre • N tracks • duration".
+    pub info_line: String,
+    pub quality_tier: String,
+    pub artwork_url: String,
+    pub tracks: Vec<TrackData>,
+}
+
+pub struct TrackData {
+    pub number: String,
+    pub title: String,
+    pub artist: String,
+    pub duration: String,
+    pub quality_tier: String,
+    pub explicit: bool,
+}
+
+/// Fetch and map a full album by id.
+pub async fn load_album<A>(runtime: &Arc<AppRuntime<A>>, album_id: &str) -> Result<AlbumData, String>
+where
+    A: FrontendAdapter + Send + Sync + 'static,
+{
+    let album = runtime
+        .core()
+        .get_album(album_id)
+        .await
+        .map_err(|e| e.to_string())?;
+    Ok(map_album(album))
+}
+
+fn map_album(album: Album) -> AlbumData {
+    let artist = album.artist.name.clone();
+
+    let year = album
+        .release_date_original
+        .as_deref()
+        .and_then(|date| date.get(0..4))
+        .unwrap_or("")
+        .to_string();
+
+    let mut parts: Vec<String> = Vec::new();
+    if !year.is_empty() {
+        parts.push(year);
+    }
+    if let Some(label) = album.label.as_ref().filter(|l| !l.name.is_empty()) {
+        parts.push(label.name.clone());
+    }
+    if let Some(genre) = album.genre.as_ref().filter(|g| !g.name.is_empty()) {
+        parts.push(genre.name.clone());
+    }
+    if let Some(count) = album.tracks_count {
+        parts.push(format!("{count} tracks"));
+    }
+    if let Some(duration) = album.duration {
+        parts.push(format_duration(duration));
+    }
+    let info_line = parts.join("   •   ");
+
+    let quality_tier = tier(album.maximum_bit_depth).to_string();
+    let artwork_url = album.image.best().cloned().unwrap_or_default();
+    let tracks = album
+        .tracks
+        .map(|container| container.items)
+        .unwrap_or_default()
+        .into_iter()
+        .map(map_track)
+        .collect();
+
+    AlbumData {
+        title: album.title,
+        artist,
+        info_line,
+        quality_tier,
+        artwork_url,
+        tracks,
+    }
+}
+
+fn map_track(track: Track) -> TrackData {
+    let mut title = track.title;
+    if let Some(version) = track.version.as_ref().filter(|v| !v.is_empty()) {
+        title = format!("{title} ({version})");
+    }
+    TrackData {
+        number: track.track_number.to_string(),
+        title,
+        artist: track.performer.map(|p| p.name).unwrap_or_default(),
+        duration: mmss(track.duration),
+        quality_tier: tier(track.maximum_bit_depth).to_string(),
+        explicit: track.parental_warning,
+    }
+}
+
+/// 24-bit and up is Hi-Res, anything else with depth info is CD-quality.
+fn tier(bit_depth: Option<u32>) -> &'static str {
+    match bit_depth {
+        Some(depth) if depth >= 24 => "hires",
+        Some(_) => "cd",
+        None => "",
+    }
+}
+
+/// `m:ss` track duration.
+fn mmss(secs: u32) -> String {
+    format!("{}:{:02}", secs / 60, secs % 60)
+}
+
+/// `Xh Ym` / `Ym` album duration.
+fn format_duration(secs: u32) -> String {
+    let hours = secs / 3600;
+    let minutes = (secs % 3600) / 60;
+    if hours > 0 {
+        format!("{hours}h {minutes}m")
+    } else {
+        format!("{minutes}m")
+    }
+}
+
+/// Apply album data to the `AlbumState` global. Runs on the Slint event loop.
+pub fn apply_album(window: &AppWindow, data: AlbumData) {
+    let tracks: Vec<AlbumTrackItem> = data
+        .tracks
+        .into_iter()
+        .map(|track| AlbumTrackItem {
+            number: track.number.into(),
+            title: track.title.into(),
+            artist: track.artist.into(),
+            duration: track.duration.into(),
+            quality_tier: track.quality_tier.into(),
+            explicit: track.explicit,
+        })
+        .collect();
+
+    let state = window.global::<AlbumState>();
+    state.set_title(data.title.into());
+    state.set_artist(data.artist.into());
+    state.set_info_line(data.info_line.into());
+    state.set_quality_tier(data.quality_tier.into());
+    state.set_tracks(ModelRc::new(VecModel::from(tracks)));
+}
+
+/// Clear album state and show an empty track list (used when opening a new
+/// album so the previous one does not flash).
+pub fn reset_album(window: &AppWindow) {
+    let state = window.global::<AlbumState>();
+    state.set_tracks(ModelRc::new(VecModel::from(Vec::<AlbumTrackItem>::new())));
+    state.set_artwork(slint::Image::default());
+    state.set_loading(true);
+}
+
+/// Apply decoded header artwork pixels. Runs on the Slint event loop.
+pub fn apply_artwork(window: &AppWindow, pixels: &[u8], width: u32, height: u32) {
+    let mut buffer = slint::SharedPixelBuffer::<slint::Rgba8Pixel>::new(width, height);
+    let dst = buffer.make_mut_bytes();
+    if dst.len() != pixels.len() {
+        return;
+    }
+    dst.copy_from_slice(pixels);
+    window
+        .global::<AlbumState>()
+        .set_artwork(slint::Image::from_rgba8(buffer));
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn mmss_pads_seconds() {
+        assert_eq!(mmss(5), "0:05");
+        assert_eq!(mmss(65), "1:05");
+        assert_eq!(mmss(225), "3:45");
+    }
+
+    #[test]
+    fn duration_drops_zero_hours() {
+        assert_eq!(format_duration(2700), "45m");
+        assert_eq!(format_duration(3720), "1h 2m");
+    }
+
+    #[test]
+    fn tier_classifies_bit_depth() {
+        assert_eq!(tier(Some(24)), "hires");
+        assert_eq!(tier(Some(16)), "cd");
+        assert_eq!(tier(None), "");
+    }
+}

crates/qbz-slint/src/artwork.rs

@@ -73,7 +73,8 @@ pub fn spawn_loads(jobs: Vec<ArtworkJob>, window: slint::Weak<AppWindow>, cache:
         let cache = cache.clone();
         tokio::spawn(async move {
             let _permit = semaphore.acquire().await.ok()?;
-            let (pixels, width, height) = fetch_and_decode(&job.url, &cache).await?;
+            let (pixels, width, height) =
+                fetch_and_decode(&job.url, &cache, DECODE_SIZE).await?;
             let _ = window.upgrade_in_event_loop(move |w| {
                 apply_artwork(&w, job.section_idx, job.album_idx, &pixels, width, height);
             });
@@ -82,10 +83,14 @@ pub fn spawn_loads(jobs: Vec<ArtworkJob>, window: slint::Weak<AppWindow>, cache:
     }
 }
 
-/// Resolve one cover image to raw RGBA8 pixels, downscaled to `DECODE_SIZE`.
+/// Resolve one cover image to raw RGBA8 pixels, downscaled to `decode_size`.
 /// Reads from the shared cache on a hit; on a miss downloads, stores, and
 /// uses the bytes. Runs on a worker thread; the result tuple is `Send`.
-async fn fetch_and_decode(url: &str, cache: &ImageCache) -> Option<(Vec<u8>, u32, u32)> {
+pub async fn fetch_and_decode(
+    url: &str,
+    cache: &ImageCache,
+    decode_size: u32,
+) -> Option<(Vec<u8>, u32, u32)> {
     let cached_path = {
         let guard = cache.lock().ok()?;
         guard.as_ref().and_then(|service| service.get(url))
@@ -106,7 +111,7 @@ async fn fetch_and_decode(url: &str, cache: &ImageCache) -> Option<(Vec<u8>, u32
 
     let rgba = image::load_from_memory(&bytes)
         .ok()?
-        .thumbnail(DECODE_SIZE, DECODE_SIZE)
+        .thumbnail(decode_size, decode_size)
         .to_rgba8();
     let (width, height) = rgba.dimensions();
     Some((rgba.into_raw(), width, height))

crates/qbz-slint/src/main.rs

@@ -15,6 +15,7 @@
 slint::include_modules!();
 
 mod adapter;
+mod album;
 mod artwork;
 mod auth;
 mod commands;
@@ -186,6 +187,50 @@ fn main() -> Result<(), Box<dyn std::error::Error>> {
         });
     }
 
+    // Open an album: load it, show the album view, then fetch its artwork.
+    {
+        let runtime = app_runtime.clone();
+        let weak = window.as_weak();
+        let handle = tokio_rt.handle().clone();
+        let image_cache = image_cache.clone();
+        window.on_open_album(move |album_id| {
+            let runtime = runtime.clone();
+            let weak = weak.clone();
+            let image_cache = image_cache.clone();
+            let album_id = album_id.to_string();
+            handle.spawn(async move {
+                let _ = weak.upgrade_in_event_loop(|w| {
+                    album::reset_album(&w);
+                    w.global::<NavState>().set_showing_album(true);
+                });
+                match album::load_album(&runtime, &album_id).await {
+                    Ok(data) => {
+                        let artwork_url = data.artwork_url.clone();
+                        let _ = weak.upgrade_in_event_loop(move |w| {
+                            album::apply_album(&w, data);
+                            w.global::<AlbumState>().set_loading(false);
+                        });
+                        if !artwork_url.is_empty() {
+                            if let Some((pixels, width, height)) =
+                                artwork::fetch_and_decode(&artwork_url, &image_cache, 448).await
+                            {
+                                let _ = weak.upgrade_in_event_loop(move |w| {
+                                    album::apply_artwork(&w, &pixels, width, height);
+                                });
+                            }
+                        }
+                    }
+                    Err(e) => {
+                        log::error!("[qbz-slint] album load failed: {e}");
+                        let _ = weak.upgrade_in_event_loop(|w| {
+                            w.global::<AlbumState>().set_loading(false);
+                        });
+                    }
+                }
+            });
+        });
+    }
+
     window.on_open_tos(|| {
         dispatch(AppCommand::OpenTermsOfService);
         if let Err(e) = open::that(QOBUZ_TOS_URL) {

crates/qbz-slint/ui/album/AlbumPageView.slint

@@ -0,0 +1,304 @@
+// Album detail page.
+//
+// Mirrors the Svelte AlbumDetailView: back button, an album header
+// (artwork + title / artist / info line / action buttons), a divider,
+// and the track list with a column header. Data comes from the
+// AlbumState global; the action buttons are visual for now.
+
+import { Theme } from "../foundation/semantic-colors.slint";
+import { Typography } from "../foundation/typography.slint";
+import { Radius } from "../foundation/radius.slint";
+import { Spacing } from "../foundation/spacing.slint";
+import { AlbumState, AlbumTrackItem, NavState } from "../state.slint";
+import { ScrollView } from "std-widgets.slint";
+
+component CircleAction inherits Rectangle {
+    in property <string> glyph;
+    in property <bool> primary: false;
+    in property <length> diameter: 40px;
+    callback clicked();
+
+    width: root.diameter;
+    height: root.diameter;
+    border-radius: root.diameter / 2;
+    background: root.primary
+        ? (ta.has-hover ? Theme.accent-hover : Theme.accent)
+        : (ta.has-hover ? Theme.surface-hover : Theme.surface-elevated);
+
+    Text {
+        text: root.glyph;
+        color: root.primary ? Theme.accent-text : Theme.text-secondary;
+        font-size: 16px;
+        horizontal-alignment: center;
+        vertical-alignment: center;
+    }
+
+    ta := TouchArea {
+        mouse-cursor: pointer;
+        clicked => {
+            root.clicked();
+        }
+    }
+}
+
+component TrackRow inherits Rectangle {
+    in property <AlbumTrackItem> track;
+    in property <int> index;
+
+    height: 56px;
+    border-radius: 8px;
+    background: ta.has-hover
+        ? Theme.surface-hover
+        : (Math.mod(root.index, 2) == 1 ? Theme.surface-card : transparent);
+
+    HorizontalLayout {
+        padding-left: 12px;
+        padding-right: 12px;
+        spacing: 16px;
+
+        Text {
+            text: root.track.number;
+            width: 32px;
+            color: Theme.text-muted;
+            font-size: Typography.body;
+            vertical-alignment: center;
+        }
+
+        VerticalLayout {
+            alignment: center;
+            horizontal-stretch: 1;
+            spacing: 2px;
+
+            HorizontalLayout {
+                spacing: 6px;
+                Text {
+                    text: root.track.title;
+                    color: Theme.text-primary;
+                    font-size: Typography.body;
+                    font-weight: Typography.medium;
+                    vertical-alignment: center;
+                    overflow: elide;
+                }
+                if root.track.explicit: Rectangle {
+                    width: 16px;
+                    height: 16px;
+                    y: (parent.height - self.height) / 2;
+                    border-radius: 3px;
+                    background: Theme.surface-elevated;
+                    Text {
+                        text: "E";
+                        color: Theme.text-muted;
+                        font-size: 9px;
+                        font-weight: Typography.semibold;
+                        horizontal-alignment: center;
+                        vertical-alignment: center;
+                    }
+                }
+            }
+            Text {
+                text: root.track.artist;
+                visible: root.track.artist != "";
+                color: Theme.text-muted;
+                font-size: Typography.link;
+                overflow: elide;
+            }
+        }
+
+        Text {
+            text: root.track.duration;
+            width: 80px;
+            color: Theme.text-muted;
+            font-size: Typography.body;
+            horizontal-alignment: center;
+            vertical-alignment: center;
+        }
+        Text {
+            text: root.track.quality-tier == "hires"
+                ? "Hi-Res"
+                : (root.track.quality-tier == "cd" ? "CD" : "");
+            width: 80px;
+            color: Theme.text-muted;
+            font-size: Typography.legal;
+            horizontal-alignment: center;
+            vertical-alignment: center;
+        }
+    }
+
+    ta := TouchArea {
+        mouse-cursor: pointer;
+    }
+}
+
+export component AlbumPageView inherits Rectangle {
+    background: Theme.surface-main;
+
+    ScrollView {
+        VerticalLayout {
+            padding-left: 24px;
+            padding-right: 24px;
+            padding-top: 14px;
+            padding-bottom: 100px;
+            spacing: 0px;
+            alignment: start;
+
+            // --- Back button -------------------------------------------------
+            back := TouchArea {
+                width: back-row.preferred-width;
+                height: 28px;
+                mouse-cursor: pointer;
+                clicked => {
+                    NavState.showing-album = false;
+                }
+                back-row := HorizontalLayout {
+                    spacing: 6px;
+                    Text {
+                        text: "‹";
+                        color: back.has-hover ? Theme.text-secondary : Theme.text-muted;
+                        font-size: 18px;
+                        vertical-alignment: center;
+                    }
+                    Text {
+                        text: @tr("Back");
+                        color: back.has-hover ? Theme.text-secondary : Theme.text-muted;
+                        font-size: Typography.body;
+                        vertical-alignment: center;
+                    }
+                }
+            }
+
+            Rectangle { height: 22px; }
+
+            // --- Album header ------------------------------------------------
+            HorizontalLayout {
+                spacing: 32px;
+                alignment: start;
+
+                Rectangle {
+                    width: 224px;
+                    height: 224px;
+                    border-radius: 12px;
+                    background: Theme.surface-elevated;
+                    drop-shadow-blur: 32px;
+                    drop-shadow-color: #00000080;
+                    drop-shadow-offset-y: 8px;
+                    clip: true;
+                    Image {
+                        width: 100%;
+                        height: 100%;
+                        source: AlbumState.artwork;
+                        image-fit: cover;
+                    }
+                }
+
+                VerticalLayout {
+                    alignment: start;
+                    padding-top: 4px;
+                    spacing: 0px;
+                    horizontal-stretch: 1;
+
+                    Text {
+                        text: AlbumState.title;
+                        color: Theme.text-primary;
+                        font-size: Typography.title;
+                        font-weight: Typography.bold;
+                        overflow: elide;
+                    }
+                    Rectangle { height: 4px; }
+                    Text {
+                        text: AlbumState.artist;
+                        color: Theme.accent;
+                        font-size: Typography.heading;
+                        font-weight: Typography.medium;
+                        overflow: elide;
+                    }
+                    Rectangle { height: 10px; }
+                    Text {
+                        text: AlbumState.info-line;
+                        color: Theme.text-muted;
+                        font-size: Typography.body;
+                        overflow: elide;
+                    }
+                    Rectangle { height: 20px; }
+                    HorizontalLayout {
+                        alignment: start;
+                        spacing: 12px;
+                        CircleAction { glyph: "▶"; primary: true; diameter: 44px; }
+                        VerticalLayout {
+                            alignment: center;
+                            CircleAction { glyph: "⇄"; }
+                        }
+                        VerticalLayout {
+                            alignment: center;
+                            CircleAction { glyph: "♡"; }
+                        }
+                        VerticalLayout {
+                            alignment: center;
+                            CircleAction { glyph: "⋯"; }
+                        }
+                    }
+                }
+            }
+
+            Rectangle { height: 20px; }
+            Rectangle {
+                height: 1px;
+                background: Theme.border-subtle;
+            }
+            Rectangle { height: 8px; }
+
+            // --- Track list --------------------------------------------------
+            if AlbumState.loading && AlbumState.tracks.length == 0: Text {
+                text: @tr("Loading album...");
+                color: Theme.text-muted;
+                font-size: Typography.body;
+            }
+
+            // Column header.
+            HorizontalLayout {
+                height: 40px;
+                padding-left: 12px;
+                padding-right: 12px;
+                spacing: 16px;
+                Text {
+                    text: "#";
+                    width: 32px;
+                    color: Theme.text-muted;
+                    font-size: Typography.legal;
+                    letter-spacing: 0.5px;
+                    vertical-alignment: center;
+                }
+                Text {
+                    text: @tr("TITLE");
+                    horizontal-stretch: 1;
+                    color: Theme.text-muted;
+                    font-size: Typography.legal;
+                    letter-spacing: 0.5px;
+                    vertical-alignment: center;
+                }
+                Text {
+                    text: @tr("DURATION");
+                    width: 80px;
+                    color: Theme.text-muted;
+                    font-size: Typography.legal;
+                    letter-spacing: 0.5px;
+                    horizontal-alignment: center;
+                    vertical-alignment: center;
+                }
+                Text {
+                    text: @tr("QUALITY");
+                    width: 80px;
+                    color: Theme.text-muted;
+                    font-size: Typography.legal;
+                    letter-spacing: 0.5px;
+                    horizontal-alignment: center;
+                    vertical-alignment: center;
+                }
+            }
+
+            for track[index] in AlbumState.tracks: TrackRow {
+                track: track;
+                index: index;
+            }
+        }
+    }
+}

crates/qbz-slint/ui/app.slint

@@ -1,16 +1,16 @@
-// QBZ Slint POC — UI entry point.
+// QBZ Slint MVP — UI entry point.
 //
 // Stays thin: imports the feature screens and exports the single
 // top-level window. No raw visual constants or domain logic here
-// (POC ADR, sections 13 and 21).
+// (MVP ADR, sections 13 and 21).
 
 import { Theme } from "foundation/semantic-colors.slint";
 import { SplashScreen } from "splash/SplashScreen.slint";
 import { LoginScreen } from "login/LoginScreen.slint";
 import { AppShell } from "shell/AppShell.slint";
 
-// Re-export the HomeState global so the Rust layer can populate it.
-export { HomeState } from "state.slint";
+// Re-export the state globals so the Rust layer can populate them.
+export { HomeState, AlbumState, NavState } from "state.slint";
 
 // Which top-level screen is shown. The app starts on `splash` while it
 // restores a saved session, then resolves to `shell` or `login`.
@@ -26,11 +26,12 @@ export component AppWindow inherits Window {
 
     in-out property <AppScreen> screen: AppScreen.splash;
 
-    // Forwarded to the Rust layer, which maps them to typed AppCommands.
+    // Forwarded to the Rust layer.
     callback sign-in-via-browser();
     callback use-system-browser();
     callback start-offline();
     callback open-tos();
+    callback open-album(string);
 
     if root.screen == AppScreen.splash: SplashScreen { }
 
@@ -49,5 +50,9 @@ export component AppWindow inherits Window {
         }
     }
 
-    if root.screen == AppScreen.shell: AppShell { }
+    if root.screen == AppScreen.shell: AppShell {
+        open-album(id) => {
+            root.open-album(id);
+        }
+    }
 }

crates/qbz-slint/ui/discover/Carousel.slint

@@ -42,6 +42,7 @@ component NavButton inherits Rectangle {
 
 export component Carousel inherits VerticalLayout {
     in property <DiscoverSection> section;
+    callback album-clicked(string);
 
     property <length> card-width: 220px;
     property <length> card-height: 266px;
@@ -112,6 +113,9 @@ export component Carousel inherits VerticalLayout {
                 spacing: root.gap;
                 for album in root.section.albums: AlbumCard {
                     album: album;
+                    clicked(id) => {
+                        root.album-clicked(id);
+                    }
                 }
             }
         }

crates/qbz-slint/ui/discover/HomeView.slint

@@ -93,6 +93,8 @@ component GearButton inherits Rectangle {
 }
 
 export component HomeView inherits Rectangle {
+    callback album-clicked(string);
+
     background: Theme.surface-main;
 
     VerticalLayout {
@@ -155,6 +157,9 @@ export component HomeView inherits Rectangle {
 
                 for section in HomeState.sections: Carousel {
                     section: section;
+                    album-clicked(id) => {
+                        root.album-clicked(id);
+                    }
                 }
             }
         }

crates/qbz-slint/ui/foundation/typography.slint

@@ -6,9 +6,12 @@ export global Typography {
     out property <length> body: 14px;
     out property <length> subtitle: 14px;
     out property <length> button: 16px;
+    out property <length> heading: 18px;
+    out property <length> title: 24px;
     out property <length> wordmark: 28px;
 
     out property <int> regular: 400;
     out property <int> medium: 500;
     out property <int> semibold: 600;
+    out property <int> bold: 700;
 }

crates/qbz-slint/ui/shell/AppShell.slint

@@ -1,17 +1,19 @@
 // App shell — the post-login frame: header bar, sidebar, content
-// region, and player bar.
-//
-// The content region is a placeholder; the Discover / Home view lands
-// in the next increment. Hairlines separate the regions.
+// region, and player bar. The content region shows either the Discover
+// Home view or the Album detail view, driven by NavState.
 
 import { Theme } from "../foundation/semantic-colors.slint";
 import { Layout } from "../foundation/layout.slint";
+import { NavState } from "../state.slint";
 import { Sidebar } from "Sidebar.slint";
 import { HeaderBar } from "HeaderBar.slint";
 import { PlayerBar } from "PlayerBar.slint";
 import { HomeView } from "../discover/HomeView.slint";
+import { AlbumPageView } from "../album/AlbumPageView.slint";
 
 export component AppShell inherits Rectangle {
+    callback open-album(string);
+
     background: Theme.surface-main;
 
     VerticalLayout {
@@ -32,8 +34,18 @@ export component AppShell inherits Rectangle {
                 width: Layout.hairline;
                 background: Theme.border-subtle;
             }
-            HomeView {
+
+            // Content region — Home or Album detail.
+            Rectangle {
                 horizontal-stretch: 1;
+                background: Theme.surface-main;
+
+                if !NavState.showing-album: HomeView {
+                    album-clicked(id) => {
+                        root.open-album(id);
+                    }
+                }
+                if NavState.showing-album: AlbumPageView { }
             }
         }
 

crates/qbz-slint/ui/state.slint

@@ -26,3 +26,28 @@ export global HomeState {
     in property <[DiscoverSection]> sections: [];
     in property <bool> loading: false;
 }
+
+export struct AlbumTrackItem {
+    number: string,
+    title: string,
+    artist: string,
+    duration: string,
+    quality-tier: string,
+    explicit: bool,
+}
+
+// Album detail screen state.
+export global AlbumState {
+    in property <string> title;
+    in property <string> artist;
+    in property <string> info-line;
+    in property <string> quality-tier;
+    in property <image> artwork;
+    in property <[AlbumTrackItem]> tracks: [];
+    in property <bool> loading: false;
+}
+
+// Which content view the shell shows.
+export global NavState {
+    in-out property <bool> showing-album: false;
+}