refactor(viewer): explorer UX cleanups (menu, loading, tree, status bar)

Four small UX fixes to the asset explorer:

1. Remove the no-op "View" menu (Textures/Meshes/Audio toggles + Wireframe
   checkbox) — none were wired to anything. Dropped ViewMode + the current_mode/
   wireframe fields from ViewerState (nothing read them); the central panel
   already dispatches on which preview resource is populated.

2. Loading indicator — clicking a drawer item now flips FileBrowserState.loading
   and the central panel shows a centered spinner + "Loading <name>…" until the
   background read/decode applies, instead of leaving the previous item on screen
   with no feedback. Cleared in poll_loader_channel on FileLoaded/PakLoaded/
   Error/Cancelled.

3. Drawer shows only the .pak index, not its .pNN data segments — the segments
   are the pack's body (loaded when the .pak is opened), so listing them (with no
   preview) was noise. Dropped the virtual "<stem>.pak" folder too; the .pak now
   sits as a normal leaf in its real directory.

4. Bottom status bar no longer overflows — horizontal_wrapped, only the source's
   final path component (full path on hover), file count, and a right-aligned,
   shortened controls hint. Removed the mode label.

Viewer + formats build; all tests pass.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

crates/sylpheed-viewer/src/iso_loader.rs

@@ -597,20 +597,24 @@ fn poll_loader_channel(
                 pending.path = path;
                 pending.bytes = bytes;
                 pending.ready = true;
+                browser.loading = false;
             }
             Ok(IsoLoaderMsg::PakLoaded { name, rows, error }) => {
                 pending_pak.name = name;
                 pending_pak.rows = rows;
                 pending_pak.error = error;
                 pending_pak.ready = true;
+                browser.loading = false;
             }
             Ok(IsoLoaderMsg::Cancelled) => {
                 iso_state.loading = false;
+                browser.loading = false;
             }
             Ok(IsoLoaderMsg::Error(msg)) => {
                 error!("ISO loader: {}", msg);
                 iso_state.loading = false;
                 iso_state.error = Some(msg);
+                browser.loading = false;
             }
             Err(TryRecvError::Empty) | Err(TryRecvError::Disconnected) => break,
         }

crates/sylpheed-viewer/src/lib.rs

@@ -28,36 +28,16 @@ pub mod ui;
 /// Global viewer state, shared across all UI and rendering systems.
 #[derive(Resource)]
 pub struct ViewerState {
-    /// Which type of asset is currently being browsed / previewed.
-    pub current_mode: ViewMode,
-    /// Whether to render meshes in wireframe mode (toggle with F2).
-    pub wireframe: bool,
     /// Whether the plain-text viewer wraps long lines.
     pub text_wrap: bool,
 }
 
 impl Default for ViewerState {
     fn default() -> Self {
-        Self {
+        Self { text_wrap: true }
-            current_mode: ViewMode::Textures,
-            wireframe: false,
-            text_wrap: true,
-        }
     }
 }
 
-/// The active view / asset type being inspected.
-#[derive(Debug, Clone, Copy, PartialEq, Eq, Default)]
-pub enum ViewMode {
-    /// XPR2 texture preview (Milestone 1).
-    #[default]
-    Textures,
-    /// 3D mesh viewer (Milestone 2+).
-    Mesh,
-    /// Audio waveform / playback (Milestone 2+).
-    Audio,
-}
-
 // ── App builder ──────────────────────────────────────────────────────────────
 
 /// Build and run the viewer application.

crates/sylpheed-viewer/src/ui.rs

@@ -13,7 +13,7 @@ use crate::iso_loader::{
     FileInfo, FileSelected, IsoState, PakView, RequestOpenDir, RequestOpenIso, TextPreview,
     TexturePreview, IsoLoaderSystemSet,
 };
-use crate::{ViewerState, ViewMode};
+use crate::ViewerState;
 
 pub struct ViewerUiPlugin;
 
@@ -31,6 +31,9 @@ pub struct FileBrowserState {
     pub files: Vec<String>,
     pub selected: Option<usize>,
     pub filter: String,
+    /// True from the moment a file is clicked until its content is applied —
+    /// drives the "Loading…" indicator so the click registers immediately.
+    pub loading: bool,
 }
 
 // ── Directory tree ────────────────────────────────────────────────────────────
@@ -46,24 +49,27 @@ struct TreeDir {
     files: Vec<(String, usize)>,
 }
 
-/// Split a full path into (directory components, leaf name), grouping data
+/// True for an IPFB data segment (`foo.p00`, `foo.p01`, …). These are the pack's
-/// segments (`foo.p00`, `foo.p01`, …) under a virtual `foo.pak` directory so a
+/// data body, not standalone files — the `.pak` index is what the user opens, so
-/// pack and its segments sit together. Purely cosmetic — indices are untouched.
+/// they're hidden from the tree (their content loads when the `.pak` is opened).
+fn is_pak_segment(leaf: &str) -> bool {
+    matches!(leaf.rsplit_once('.'), Some((_, ext))
+        if ext.len() == 3
+            && ext.as_bytes()[0] == b'p'
+            && ext.as_bytes()[1].is_ascii_digit()
+            && ext.as_bytes()[2].is_ascii_digit())
+}
+
+/// Split a full path into (directory components, leaf name).
 fn split_for_tree(full: &str) -> (Vec<String>, String) {
     let mut comps: Vec<String> = full.split('/').map(str::to_string).collect();
     let leaf = comps.pop().unwrap_or_default();
-    if let Some((stem, ext)) = leaf.rsplit_once('.') {
-        let e = ext.as_bytes();
-        // `.pNN` where NN are two digits → nest under "<stem>.pak".
-        if e.len() == 3 && e[0] == b'p' && e[1].is_ascii_digit() && e[2].is_ascii_digit() {
-            comps.push(format!("{stem}.pak"));
-        }
-    }
     (comps, leaf)
 }
 
 /// Build the directory tree, keeping only leaves whose full path contains
-/// `filter` (case-insensitive; empty filter keeps everything).
+/// `filter` (case-insensitive; empty filter keeps everything). `.pNN` data
+/// segments are skipped — only their `.pak` index is shown.
 fn build_tree(files: &[String], filter: &str) -> TreeDir {
     let filter = filter.to_lowercase();
     let mut root = TreeDir::default();
@@ -72,6 +78,9 @@ fn build_tree(files: &[String], filter: &str) -> TreeDir {
             continue;
         }
         let (dirs, leaf) = split_for_tree(full);
+        if is_pak_segment(&leaf) {
+            continue;
+        }
         let mut node = &mut root;
         for comp in dirs {
             node = node.dirs.entry(comp).or_default();
@@ -83,11 +92,13 @@ fn build_tree(files: &[String], filter: &str) -> TreeDir {
 
 /// Render a directory node recursively: sub-directories (collapsible) first,
 /// then leaf files as selectable labels.
+#[allow(clippy::too_many_arguments)]
 fn render_dir(
     ui: &mut egui::Ui,
     node: &TreeDir,
     force_open: bool,
     selected: &mut Option<usize>,
+    loading: &mut bool,
     events: &mut EventWriter<FileSelected>,
     files: &[String],
 ) {
@@ -96,7 +107,7 @@ fn render_dir(
             .id_salt(name)
             .default_open(force_open)
             .show(ui, |ui| {
-                render_dir(ui, child, force_open, selected, events, files);
+                render_dir(ui, child, force_open, selected, loading, events, files);
             });
     }
     for (leaf, idx) in &node.files {
@@ -106,6 +117,7 @@ fn render_dir(
             .clicked()
         {
             *selected = Some(*idx);
+            *loading = true; // show the spinner until the content is applied
             events.send(FileSelected(files[*idx].clone()));
         }
     }
@@ -152,29 +164,6 @@ fn draw_viewer_ui(
                 );
             });
 
-            ui.menu_button("View", |ui| {
-                if ui
-                    .selectable_label(viewer.current_mode == ViewMode::Textures, "Textures")
-                    .clicked()
-                {
-                    viewer.current_mode = ViewMode::Textures;
-                }
-                if ui
-                    .selectable_label(viewer.current_mode == ViewMode::Mesh, "Meshes")
-                    .clicked()
-                {
-                    viewer.current_mode = ViewMode::Mesh;
-                }
-                if ui
-                    .selectable_label(viewer.current_mode == ViewMode::Audio, "Audio")
-                    .clicked()
-                {
-                    viewer.current_mode = ViewMode::Audio;
-                }
-                ui.separator();
-                ui.checkbox(&mut viewer.wireframe, "Wireframe (F2)");
-            });
-
             ui.menu_button("Help", |ui| {
                 if ui.button("Controls…").clicked() {
                     // TODO: controls popup
@@ -225,11 +214,15 @@ fn draw_viewer_ui(
                     let files = browser.files.clone();
                     let tree = build_tree(&files, &browser.filter);
                     let force_open = !browser.filter.is_empty();
+                    let FileBrowserState {
+                        selected, loading, ..
+                    } = &mut *browser;
                     render_dir(
                         ui,
                         &tree,
                         force_open,
-                        &mut browser.selected,
+                        selected,
+                        loading,
                         &mut file_selected_events,
                         &files,
                     );
@@ -239,27 +232,40 @@ fn draw_viewer_ui(
 
     // ── Bottom panel: status bar ──────────────────────────────────────────
     egui::TopBottomPanel::bottom("status_bar").show(ctx, |ui| {
-        ui.horizontal(|ui| {
+        // `horizontal_wrapped` so the bar wraps instead of overflowing the
+        // window on narrow widths; the controls hint is right-aligned and only
+        // the source's final path component is shown (full path on hover).
+        ui.horizontal_wrapped(|ui| {
             if let Some(label) = &iso_state.source_label {
-                ui.label(label);
+                let short = label.rsplit(['/', '\\']).next().unwrap_or(label);
+                ui.label(short).on_hover_text(label);
                 ui.separator();
             }
-            match viewer.current_mode {
-                ViewMode::Textures => ui.label("Mode: Texture Viewer"),
-                ViewMode::Mesh => ui.label("Mode: Mesh Viewer"),
-                ViewMode::Audio => ui.label("Mode: Audio Viewer"),
-            };
-            ui.separator();
             ui.label(format!("{} files", browser.files.len()));
-            ui.separator();
+            ui.with_layout(egui::Layout::right_to_left(egui::Align::Center), |ui| {
-            ui.label("LMB: orbit | RMB: pan | Scroll: zoom | R: reset");
+                ui.label("LMB orbit · RMB pan · scroll zoom · R reset");
+            });
         });
     });
 
     // ── Central area ──────────────────────────────────────────────────────
     if browser.selected.is_some() {
         egui::CentralPanel::default().show(ctx, |ui| {
-            if pak_view.loaded {
+            if browser.loading {
+                // A file was just clicked — show immediate feedback while the
+                // background read + decode runs, instead of the previous item.
+                let name = browser
+                    .selected
+                    .and_then(|i| browser.files.get(i))
+                    .map(|p| p.rsplit('/').next().unwrap_or(p))
+                    .unwrap_or("");
+                ui.centered_and_justified(|ui| {
+                    ui.horizontal(|ui| {
+                        ui.spinner();
+                        ui.label(format!("Loading {name}…"));
+                    });
+                });
+            } else if pak_view.loaded {
                 draw_pak_browser(ui, &mut pak_view);
             } else if let Some(text) = &text_preview.content {
                 // ── Plain-text viewer ──