EpisodeView: Initial refactor to make loading non-blocking.

hammond-data/src/dbqueries.rs

@@ -349,6 +349,20 @@ pub(crate) fn episode_exists(title_: &str, podcast_id_: i32) -> Result<bool, Dat
         .map_err(From::from)
 }
 
+/// Check `episode` table empty
+///
+/// Return true if `episode` table is populated.
+pub fn is_episodes_populated() -> Result<bool, DataError> {
+    use schema::episode::dsl::*;
+
+    let db = connection();
+    let con = db.get()?;
+
+    select(exists(episode.count()))
+        .get_result(&con)
+        .map_err(From::from)
+}
+
 pub(crate) fn index_new_episodes(eps: &[NewEpisode]) -> Result<(), DataError> {
     use schema::episode::dsl::*;
     let db = connection();

hammond-gtk/src/stacks/episode.rs

@@ -3,10 +3,11 @@ use gtk::prelude::*;
 use gtk::Cast;
 
 use failure::Error;
-
+use hammond_data::dbqueries::is_episodes_populated;
-use views::{EmptyView, EpisodesView};
+use hammond_data::errors::DataError;
 
 use app::Action;
+use views::{EmptyView, EpisodesView};
 
 use std::sync::mpsc::Sender;
 
@@ -24,12 +25,7 @@ impl EpisodeStack {
 
         stack.add_named(&episodes.container, "episodes");
         stack.add_named(&empty.container, "empty");
-
+        set_stack_visible(&stack)?;
-        if episodes.is_empty() {
-            stack.set_visible_child_name("empty");
-        } else {
-            stack.set_visible_child_name("episodes");
-        }
 
         Ok(EpisodeStack { stack, sender })
     }
@@ -43,28 +39,23 @@ impl EpisodeStack {
             .map_err(|_| format_err!("Failed to downcast stack child to a Box."))?;
         debug!("Name: {:?}", WidgetExt::get_name(&old));
 
-        let scrolled_window = old.get_children()
+        // let scrolled_window = old.get_children()
-            .first()
+        //     .first()
-            .ok_or_else(|| format_err!("Box container has no childs."))?
+        //     .ok_or_else(|| format_err!("Box container has no childs."))?
-            .clone()
+        //     .clone()
-            .downcast::<gtk::ScrolledWindow>()
+        //     .downcast::<gtk::ScrolledWindow>()
-            .map_err(|_| format_err!("Failed to downcast stack child to a ScrolledWindow."))?;
+        //     .map_err(|_| format_err!("Failed to downcast stack child to a ScrolledWindow."))?;
-        debug!("Name: {:?}", WidgetExt::get_name(&scrolled_window));
+        // debug!("Name: {:?}", WidgetExt::get_name(&scrolled_window));
 
         let eps = EpisodesView::new(self.sender.clone())?;
         // Copy the vertical scrollbar adjustment from the old view into the new one.
-        scrolled_window
+        // scrolled_window
-            .get_vadjustment()
+        //     .get_vadjustment()
-            .map(|x| eps.set_vadjustment(&x));
+        //     .map(|x| eps.set_vadjustment(&x));
 
         self.stack.remove(&old);
         self.stack.add_named(&eps.container, "episodes");
-
+        set_stack_visible(&self.stack)?;
-        if eps.is_empty() {
-            self.stack.set_visible_child_name("empty");
-        } else {
-            self.stack.set_visible_child_name("episodes");
-        }
 
         old.destroy();
 
@@ -75,3 +66,13 @@ impl EpisodeStack {
         self.stack.clone()
     }
 }
+
+fn set_stack_visible(stack: &gtk::Stack) -> Result<(), DataError> {
+    if is_episodes_populated()? {
+        stack.set_visible_child_name("episodes");
+    } else {
+        stack.set_visible_child_name("empty");
+    };
+
+    Ok(())
+}

hammond-gtk/src/views/episodes.rs

@@ -7,9 +7,11 @@ use hammond_data::dbqueries;
 use hammond_data::EpisodeWidgetQuery;
 
 use app::Action;
+use utils::lazy_load_full;
 use utils::{get_ignored_shows, set_image_from_path};
 use widgets::EpisodeWidget;
 
+use std::rc::Rc;
 use std::sync::mpsc::Sender;
 use std::sync::Arc;
 
@@ -78,85 +80,65 @@ impl Default for EpisodesView {
 // TODO: REFACTOR ME
 impl EpisodesView {
     #[inline]
-    pub fn new(sender: Sender<Action>) -> Result<EpisodesView, Error> {
+    pub fn new(sender: Sender<Action>) -> Result<Rc<EpisodesView>, Error> {
-        let view = EpisodesView::default();
+        let view = Rc::new(EpisodesView::default());
         let ignore = get_ignored_shows()?;
-        let episodes = dbqueries::get_episodes_widgets_filter_limit(&ignore, 50)?;
+        let episodes = dbqueries::get_episodes_widgets_filter_limit(&ignore, 200)?;
         let now_utc = Utc::now();
 
-        episodes.into_iter().for_each(|ep| {
+        let view_ = view.clone();
+        let func = move |ep: EpisodeWidgetQuery| {
             let epoch = ep.epoch();
             let viewep = EpisodesViewWidget::new(ep, sender.clone());
 
             let t = split(&now_utc, i64::from(epoch));
             match t {
                 ListSplit::Today => {
-                    view.today_list.add(&viewep.container);
+                    view_.today_list.add(&viewep.container);
                 }
                 ListSplit::Yday => {
-                    view.yday_list.add(&viewep.container);
+                    view_.yday_list.add(&viewep.container);
                 }
                 ListSplit::Week => {
-                    view.week_list.add(&viewep.container);
+                    view_.week_list.add(&viewep.container);
                 }
                 ListSplit::Month => {
-                    view.month_list.add(&viewep.container);
+                    view_.month_list.add(&viewep.container);
                 }
                 ListSplit::Rest => {
-                    view.rest_list.add(&viewep.container);
+                    view_.rest_list.add(&viewep.container);
                 }
             }
+        };
+
+        let callback = clone!(view => move || {
+            if view.today_list.get_children().is_empty() {
+                view.today_box.hide();
+            }
+
+            if view.yday_list.get_children().is_empty() {
+                view.yday_box.hide();
+            }
+
+            if view.week_list.get_children().is_empty() {
+                view.week_box.hide();
+            }
+
+            if view.month_list.get_children().is_empty() {
+                view.month_box.hide();
+            }
+
+            if view.rest_list.get_children().is_empty() {
+                view.rest_box.hide();
+            }
         });
 
-        if view.today_list.get_children().is_empty() {
+        lazy_load_full(episodes, func, callback);
-            view.today_box.hide();
-        }
-
-        if view.yday_list.get_children().is_empty() {
-            view.yday_box.hide();
-        }
-
-        if view.week_list.get_children().is_empty() {
-            view.week_box.hide();
-        }
-
-        if view.month_list.get_children().is_empty() {
-            view.month_box.hide();
-        }
-
-        if view.rest_list.get_children().is_empty() {
-            view.rest_box.hide();
-        }
 
         view.container.show_all();
         Ok(view)
     }
 
-    #[inline]
-    pub fn is_empty(&self) -> bool {
-        if !self.today_list.get_children().is_empty() {
-            return false;
-        }
-
-        if !self.yday_list.get_children().is_empty() {
-            return false;
-        }
-
-        if !self.week_list.get_children().is_empty() {
-            return false;
-        }
-
-        if !self.month_list.get_children().is_empty() {
-            return false;
-        }
-
-        if !self.rest_list.get_children().is_empty() {
-            return false;
-        }
-
-        true
-    }
-
     #[inline]
     /// Set scrolled window vertical adjustment.
     pub fn set_vadjustment(&self, vadjustment: &gtk::Adjustment) {