Add viewer navigation and file downloads

src/viewer.rs

@@ -1,4 +1,4 @@
-use std::cell::RefCell;
+use std::cell::{Cell, RefCell};
 use std::collections::{HashMap, HashSet, VecDeque};
 use std::rc::Rc;
 use std::sync::mpsc::{self, TryRecvError};
@@ -21,13 +21,42 @@ const FAST_CACHE_LIMIT_PAGES: usize = 64;
 
 pub struct ViewerWindow;
 
-pub type SiblingNavigator = Rc<dyn Fn(bool) -> bool>;
+pub struct SiblingNavigator {
+    current: usize,
+    count: usize,
+    open: Rc<dyn Fn(usize) -> bool>,
+}
+
+impl SiblingNavigator {
+    pub fn new(current: usize, count: usize, open: Rc<dyn Fn(usize) -> bool>) -> Self {
+        Self {
+            current,
+            count,
+            open,
+        }
+    }
+
+    fn open_relative(&self, forward: bool) -> bool {
+        let Some(index) = sibling_index(self.current, self.count, forward) else {
+            return false;
+        };
+        (self.open)(index)
+    }
+
+    fn open_index(&self, index: usize) -> bool {
+        index < self.count && index != self.current && (self.open)(index)
+    }
+}
 
 pub struct FavoriteControl {
     pub active: bool,
     pub toggle: Rc<dyn Fn() -> bool>,
 }
 
+pub struct FileDownloadControl {
+    pub download: Rc<dyn Fn(gtk::Window, gtk::Label)>,
+}
+
 impl ViewerWindow {
     pub fn open(
         application: &gtk::Application,
@@ -36,6 +65,7 @@ impl ViewerWindow {
         fast_image_loading: bool,
         sibling_navigator: Option<SiblingNavigator>,
         favorite_control: FavoriteControl,
+        download_control: FileDownloadControl,
     ) {
         let title = source.display_name.clone();
         let window = gtk::ApplicationWindow::builder()
@@ -47,6 +77,8 @@ impl ViewerWindow {
         let header = gtk::HeaderBar::new();
         header.set_title_widget(Some(&gtk::Label::new(Some(&title))));
         let favorite_button = gtk::Button::with_label(favorite_label(favorite_control.active));
+        let download_button = gtk::Button::with_label("파일 다운로드");
+        header.pack_end(&download_button);
         header.pack_end(&favorite_button);
         window.set_titlebar(Some(&header));
 
@@ -162,6 +194,8 @@ impl ViewerWindow {
             sibling_navigator,
             favorite_button,
             favorite_toggle: favorite_control.toggle,
+            download_button,
+            file_download: download_control.download,
             state: RefCell::new(ViewerState {
                 pages: Vec::new(),
                 anchor: 0,
@@ -240,6 +274,8 @@ struct ViewerController {
     sibling_navigator: Option<SiblingNavigator>,
     favorite_button: gtk::Button,
     favorite_toggle: Rc<dyn Fn() -> bool>,
+    download_button: gtk::Button,
+    file_download: Rc<dyn Fn(gtk::Window, gtk::Label)>,
     state: RefCell<ViewerState>,
 }
 
@@ -269,6 +305,13 @@ impl ViewerController {
             controller.favorite_button.set_label(favorite_label(active));
         });
         let controller = Rc::clone(self);
+        self.download_button.connect_clicked(move |_| {
+            (controller.file_download)(
+                controller.window.clone().upcast(),
+                controller.status_label.clone(),
+            );
+        });
+        let controller = Rc::clone(self);
         self.page_seek.connect_value_changed(move |scale| {
             if let Some(index) =
                 page_seek_index(scale.value(), controller.state.borrow().pages.len())
@@ -339,7 +382,7 @@ impl ViewerController {
 
     fn open_sibling(&self, forward: bool) {
         if let Some(navigate) = &self.sibling_navigator
-            && navigate(forward)
+            && navigate.open_relative(forward)
         {
             self.window.close();
         }
@@ -945,6 +988,7 @@ impl MediaViewerWindow {
         kind: EntryKind,
         sibling_navigator: Option<SiblingNavigator>,
         favorite_control: FavoriteControl,
+        download_control: FileDownloadControl,
     ) {
         let title = source.display_name.clone();
         let window = gtk::ApplicationWindow::builder()
@@ -956,6 +1000,8 @@ impl MediaViewerWindow {
         let header = gtk::HeaderBar::new();
         header.set_title_widget(Some(&gtk::Label::new(Some(&title))));
         let favorite_button = gtk::Button::with_label(favorite_label(favorite_control.active));
+        let download_button = gtk::Button::with_label("파일 다운로드");
+        header.pack_end(&download_button);
         header.pack_end(&favorite_button);
         window.set_titlebar(Some(&header));
 
@@ -982,7 +1028,19 @@ impl MediaViewerWindow {
             .margin_start(8)
             .margin_end(8)
             .build();
+        let media_seek = gtk::Scale::with_range(gtk::Orientation::Horizontal, 0.0, 0.0, 1.0);
+        media_seek.set_draw_value(false);
+        media_seek.set_margin_start(8);
+        media_seek.set_margin_end(8);
+        if let Some(navigator) = &sibling_navigator {
+            media_seek.set_range(0.0, navigator.count.saturating_sub(1) as f64);
+            media_seek.set_value(navigator.current as f64);
+            media_seek.set_sensitive(navigator.count > 1);
+        } else {
+            media_seek.set_sensitive(false);
+        }
         root.append(&stack);
+        root.append(&media_seek);
         root.append(&status_label);
         window.set_child(Some(&root));
 
@@ -993,9 +1051,14 @@ impl MediaViewerWindow {
             video,
             stack,
             status_label,
+            media_seek,
             sibling_navigator,
             favorite_button,
             favorite_toggle: favorite_control.toggle,
+            download_button,
+            file_download: download_control.download,
+            seek_generation: Cell::new(0),
+            seek_opening: Cell::new(false),
         });
         if let Some(stream) = controller.video.media_stream() {
             let status_label = controller.status_label.clone();
@@ -1027,9 +1090,14 @@ struct MediaViewerController {
     video: gtk::Video,
     stack: gtk::Stack,
     status_label: gtk::Label,
+    media_seek: gtk::Scale,
     sibling_navigator: Option<SiblingNavigator>,
     favorite_button: gtk::Button,
     favorite_toggle: Rc<dyn Fn() -> bool>,
+    download_button: gtk::Button,
+    file_download: Rc<dyn Fn(gtk::Window, gtk::Label)>,
+    seek_generation: Cell<u64>,
+    seek_opening: Cell<bool>,
 }
 
 impl MediaViewerController {
@@ -1061,19 +1129,67 @@ impl MediaViewerController {
             let active = (controller.favorite_toggle)();
             controller.favorite_button.set_label(favorite_label(active));
         });
+        let controller = Rc::clone(self);
+        self.download_button.connect_clicked(move |_| {
+            (controller.file_download)(
+                controller.window.clone().upcast(),
+                controller.status_label.clone(),
+            );
+        });
+        let controller = Rc::clone(self);
+        self.media_seek.connect_value_changed(move |scale| {
+            let Some(navigator) = &controller.sibling_navigator else {
+                return;
+            };
+            let Some(index) = page_seek_index(scale.value(), navigator.count) else {
+                return;
+            };
+            controller.schedule_seek(index);
+        });
     }
 
     fn open_sibling(&self, forward: bool) {
         if let Some(navigate) = &self.sibling_navigator
-            && navigate(forward)
+            && navigate.open_relative(forward)
         {
-            if let Some(stream) = self.video.media_stream() {
-                stream.pause();
-            }
-            self.window.close();
+            self.close_for_navigation();
         }
     }
 
+    fn schedule_seek(self: &Rc<Self>, index: usize) {
+        let Some(navigator) = &self.sibling_navigator else {
+            return;
+        };
+        if index == navigator.current || self.seek_opening.get() {
+            return;
+        }
+        let generation = self.seek_generation.get().wrapping_add(1);
+        self.seek_generation.set(generation);
+        let controller = Rc::downgrade(self);
+        glib::timeout_add_local_once(Duration::from_millis(180), move || {
+            let Some(controller) = controller.upgrade() else {
+                return;
+            };
+            if controller.seek_generation.get() != generation || controller.seek_opening.get() {
+                return;
+            }
+            let Some(navigator) = &controller.sibling_navigator else {
+                return;
+            };
+            if navigator.open_index(index) {
+                controller.seek_opening.set(true);
+                controller.close_for_navigation();
+            }
+        });
+    }
+
+    fn close_for_navigation(&self) {
+        if let Some(stream) = self.video.media_stream() {
+            stream.pause();
+        }
+        self.window.close();
+    }
+
     fn toggle_fullscreen(&self) {
         if self.window.is_fullscreen() {
             self.window.unfullscreen();
@@ -1196,6 +1312,14 @@ fn page_seek_index(value: f64, count: usize) -> Option<usize> {
     (count > 0).then(|| (value.round().max(0.0) as usize).min(count - 1))
 }
 
+fn sibling_index(current: usize, count: usize, forward: bool) -> Option<usize> {
+    if forward {
+        (current + 1 < count).then_some(current + 1)
+    } else {
+        current.checked_sub(1)
+    }
+}
+
 #[cfg(test)]
 mod tests {
     use super::*;
@@ -1245,4 +1369,12 @@ mod tests {
         assert_eq!(page_seek_index(20.0, 10), Some(9));
         assert_eq!(page_seek_index(0.0, 0), None);
     }
+
+    #[test]
+    fn sibling_navigation_stops_at_boundaries() {
+        assert_eq!(sibling_index(1, 3, false), Some(0));
+        assert_eq!(sibling_index(1, 3, true), Some(2));
+        assert_eq!(sibling_index(0, 3, false), None);
+        assert_eq!(sibling_index(2, 3, true), None);
+    }
 }