Replace matches vec with a channel

src/tui/app/machine/browse.rs

@@ -1,4 +1,4 @@
-use std::{thread, time};
+use std::{sync::mpsc, thread, time};
 
 use musichoard::collection::musicbrainz::IMusicBrainzRef;
 
@@ -91,7 +91,7 @@ impl IAppInteractBrowse for AppMachine<AppBrowse> {
             }
         };
 
-        let mut matches = vec![];
+        let (matches_tx, matches_rx) = mpsc::channel::<AppMatchesInfo>();
 
         match artist.musicbrainz {
             Some(ref mbid) => {
@@ -104,7 +104,9 @@ impl IAppInteractBrowse for AppMachine<AppBrowse> {
                     }
 
                     match self.inner.musicbrainz.search_release_group(arid, album) {
-                        Ok(list) => matches.push(AppMatchesInfo::album(album.clone(), list)),
+                        Ok(list) => matches_tx
+                            .send(AppMatchesInfo::album(album.clone(), list))
+                            .expect("send fails only if receiver is disconnected"),
                         Err(err) => return AppMachine::error(self.inner, err.to_string()).into(),
                     }
 
@@ -114,12 +116,14 @@ impl IAppInteractBrowse for AppMachine<AppBrowse> {
                 }
             }
             None => match self.inner.musicbrainz.search_artist(artist) {
-                Ok(list) => matches.push(AppMatchesInfo::artist(artist.clone(), list)),
+                Ok(list) => matches_tx
+                    .send(AppMatchesInfo::artist(artist.clone(), list))
+                    .expect("send fails only if receiver is disconnected"),
                 Err(err) => return AppMachine::error(self.inner, err.to_string()).into(),
             },
         };
 
-        AppMachine::matches(self.inner, matches).into()
+        AppMachine::matches(self.inner, matches_rx).into()
     }
 
     fn no_op(self) -> Self::APP {
@@ -135,7 +139,8 @@ mod tests {
     use crate::tui::{
         app::{
             machine::tests::{inner, inner_with_mb, music_hoard},
-            Category, IAppAccess, IAppInteract, IAppInteractMatches,
+            AppPublicAlbumMatches, AppPublicArtistMatches, AppPublicMatchesInfo, Category,
+            IAppAccess, IAppInteract, IAppInteractMatches,
         },
         lib::interface::musicbrainz::{self, Match, MockIMusicBrainz},
         testmod::COLLECTION,
@@ -258,19 +263,11 @@ mod tests {
 
         let public_matches = public.state.unwrap_matches();
 
-        assert_eq!(
-            public_matches
-                .matches
-                .as_ref()
-                .unwrap()
-                .album_ref()
-                .matching,
-            &album_1
-        );
-        assert_eq!(
-            public_matches.matches.as_ref().unwrap().album_ref().list,
-            matches_1.as_slice()
-        );
+        let expected = Some(AppPublicMatchesInfo::Album(AppPublicAlbumMatches {
+            matching: &album_1,
+            list: &matches_1,
+        }));
+        assert_eq!(public_matches.matches, expected);
 
         let mut app = app.unwrap_matches().select();
 
@@ -279,19 +276,11 @@ mod tests {
 
         let public_matches = public.state.unwrap_matches();
 
-        assert_eq!(
-            public_matches
-                .matches
-                .as_ref()
-                .unwrap()
-                .album_ref()
-                .matching,
-            &album_4
-        );
-        assert_eq!(
-            public_matches.matches.as_ref().unwrap().album_ref().list,
-            matches_4.as_slice()
-        );
+        let expected = Some(AppPublicMatchesInfo::Album(AppPublicAlbumMatches {
+            matching: &album_4,
+            list: &matches_4,
+        }));
+        assert_eq!(public_matches.matches, expected);
 
         let app = app.unwrap_matches().select();
         app.unwrap_browse();
@@ -335,19 +324,11 @@ mod tests {
 
         let public_matches = public.state.unwrap_matches();
 
-        assert_eq!(
-            public_matches
-                .matches
-                .as_ref()
-                .unwrap()
-                .artist_ref()
-                .matching,
-            &artist
-        );
-        assert_eq!(
-            public_matches.matches.as_ref().unwrap().artist_ref().list,
-            matches.as_slice()
-        );
+        let expected = Some(AppPublicMatchesInfo::Artist(AppPublicArtistMatches {
+            matching: &artist,
+            list: &matches,
+        }));
+        assert_eq!(public_matches.matches, expected);
 
         let app = app.unwrap_matches().select();
         app.unwrap_browse();

src/tui/app/machine/matches.rs

@@ -1,4 +1,4 @@
-use std::cmp;
+use std::{cmp, sync::mpsc};
 
 use musichoard::collection::{album::Album, artist::Artist};
 
@@ -101,30 +101,20 @@ impl<'app> From<&'app AppMatchesInfo> for AppPublicMatchesInfo<'app> {
 }
 
 pub struct AppMatches {
-    matches_info_vec: Vec<AppMatchesInfo>,
-    index: Option<usize>,
+    matches_rx: mpsc::Receiver<AppMatchesInfo>,
+    current: Option<AppMatchesInfo>,
     state: WidgetState,
 }
 
 impl AppMachine<AppMatches> {
-    pub fn matches(inner: AppInner, matches_info_vec: Vec<AppMatchesInfo>) -> Self {
-        let mut index = None;
-        let mut state = WidgetState::default();
-        if let Some(matches_info) = matches_info_vec.first() {
-            index = Some(0);
-            if !matches_info.is_empty() {
-                state.list.select(Some(0));
-            }
-        }
-
-        AppMachine {
-            inner,
-            state: AppMatches {
-                matches_info_vec,
-                index,
-                state,
-            },
-        }
+    pub fn matches(inner: AppInner, matches_rx: mpsc::Receiver<AppMatchesInfo>) -> Self {
+        let mut state = AppMatches {
+            matches_rx,
+            current: None,
+            state: WidgetState::default(),
+        };
+        state.next_matches_info();
+        AppMachine { inner, state }
     }
 }
 
@@ -136,15 +126,10 @@ impl From<AppMachine<AppMatches>> for App {
 
 impl<'a> From<&'a mut AppMachine<AppMatches>> for AppPublic<'a> {
     fn from(machine: &'a mut AppMachine<AppMatches>) -> Self {
-        let matches = machine
-            .state
-            .index
-            .map(|index| (&machine.state.matches_info_vec[index]).into());
-
         AppPublic {
             inner: (&mut machine.inner).into(),
             state: AppState::Matches(AppPublicMatches {
-                matches,
+                matches: machine.state.current.as_ref().map(Into::into),
                 state: &mut machine.state.state,
             }),
         }
@@ -155,8 +140,8 @@ impl IAppInteractMatches for AppMachine<AppMatches> {
     type APP = App;
 
     fn prev_match(mut self) -> Self::APP {
-        if let Some(list_index) = self.state.state.list.selected() {
-            let result = list_index.saturating_sub(1);
+        if let Some(index) = self.state.state.list.selected() {
+            let result = index.saturating_sub(1);
             self.state.state.list.select(Some(result));
         }
 
@@ -164,11 +149,14 @@ impl IAppInteractMatches for AppMachine<AppMatches> {
     }
 
     fn next_match(mut self) -> Self::APP {
-        if let Some(list_index) = self.state.state.list.selected() {
-            let result = list_index.saturating_add(1);
+        if let Some(index) = self.state.state.list.selected() {
+            let result = index.saturating_add(1);
             let to = cmp::min(
                 result,
-                self.state.matches_info_vec[self.state.index.unwrap()]
+                self.state
+                    .current
+                    .as_ref()
+                    .expect("selected() implies current exists")
                     .len()
                     .saturating_sub(1),
             );
@@ -179,18 +167,17 @@ impl IAppInteractMatches for AppMachine<AppMatches> {
     }
 
     fn select(mut self) -> Self::APP {
-        self.state.index = self.state.index.map(|i| i.saturating_add(1));
-        self.state.state = WidgetState::default();
-        if let Some(index) = self.state.index {
-            if let Some(matches_info) = self.state.matches_info_vec.get(index) {
+        self.state.next_matches_info();
+        match self.state.current {
+            Some(ref matches_info) => {
+                self.state.state = WidgetState::default();
                 if !matches_info.is_empty() {
                     self.state.state.list.select(Some(0));
                 }
-                return self.into();
+                self.into()
             }
+            None => AppMachine::browse(self.inner).into(),
         }
-
-        AppMachine::browse(self.inner).into()
     }
 
     fn abort(self) -> Self::APP {
@@ -202,8 +189,29 @@ impl IAppInteractMatches for AppMachine<AppMatches> {
     }
 }
 
+trait IAppInteractMatchesPrivate {
+    fn next_matches_info(&mut self);
+}
+
+impl IAppInteractMatchesPrivate for AppMatches {
+    fn next_matches_info(&mut self) {
+        // FIXME: try_recv might not be appropriate for asynchronous version.
+        (self.current, self.state) = match self.matches_rx.try_recv() {
+            Ok(next_match) => {
+                let mut state = WidgetState::default();
+                if !next_match.is_empty() {
+                    state.list.select(Some(0));
+                }
+                (Some(next_match), state)
+            }
+            Err(_) => (None, WidgetState::default()),
+        }
+    }
+}
+
 #[cfg(test)]
 mod tests {
+    use mpsc::Receiver;
     use musichoard::collection::{
         album::{AlbumDate, AlbumId, AlbumPrimaryType, AlbumSecondaryType},
         artist::ArtistId,
@@ -216,15 +224,6 @@ mod tests {
 
     use super::*;
 
-    impl AppMatchesInfo {
-        fn album_ref(&self) -> &AppAlbumMatchesInfo {
-            match self {
-                Self::Album(a) => a,
-                Self::Artist(_) => panic!(),
-            }
-        }
-    }
-
     fn artist_matches_info_vec() -> Vec<AppMatchesInfo> {
         let artist_1 = Artist::new(ArtistId::new("Artist 1"));
 
@@ -284,14 +283,21 @@ mod tests {
         vec![matches_info_1, matches_info_2]
     }
 
+    fn receiver(matches_info_vec: Vec<AppMatchesInfo>) -> Receiver<AppMatchesInfo> {
+        let (tx, rx) = mpsc::channel();
+        for matches_info in matches_info_vec.into_iter() {
+            tx.send(matches_info).unwrap();
+        }
+        rx
+    }
+
     #[test]
     fn create_empty() {
-        let matches = AppMachine::matches(inner(music_hoard(vec![])), vec![]);
+        let matches = AppMachine::matches(inner(music_hoard(vec![])), receiver(vec![]));
 
         let widget_state = WidgetState::default();
 
-        assert_eq!(matches.state.matches_info_vec, vec![]);
-        assert_eq!(matches.state.index, None);
+        assert_eq!(matches.state.current, None);
         assert_eq!(matches.state.state, widget_state);
 
         let mut app = matches.no_op();
@@ -305,63 +311,55 @@ mod tests {
     #[test]
     fn create_nonempty() {
         let matches_info_vec = album_matches_info_vec();
-        let matches = AppMachine::matches(inner(music_hoard(vec![])), matches_info_vec.clone());
+        let matches = AppMachine::matches(
+            inner(music_hoard(vec![])),
+            receiver(matches_info_vec.clone()),
+        );
 
         let mut widget_state = WidgetState::default();
         widget_state.list.select(Some(0));
 
-        assert_eq!(matches.state.matches_info_vec, matches_info_vec);
-        assert_eq!(matches.state.index, Some(0));
+        assert_eq!(matches.state.current.as_ref(), Some(&matches_info_vec[0]));
         assert_eq!(matches.state.state, widget_state);
 
         let mut app = matches.no_op();
         let public = app.get();
         let public_matches = public.state.unwrap_matches();
 
-        assert_eq!(
-            public_matches
-                .matches
-                .as_ref()
-                .unwrap()
-                .album_ref()
-                .matching,
-            &matches_info_vec[0].album_ref().matching
-        );
-        assert_eq!(
-            public_matches.matches.as_ref().unwrap().album_ref().list,
-            matches_info_vec[0].album_ref().list.as_slice()
-        );
+        assert_eq!(public_matches.matches, Some((&matches_info_vec[0]).into()));
         assert_eq!(public_matches.state, &widget_state);
     }
 
     fn matches_flow(matches_info_vec: Vec<AppMatchesInfo>) {
-        let matches = AppMachine::matches(inner(music_hoard(vec![])), matches_info_vec.clone());
+        let matches = AppMachine::matches(
+            inner(music_hoard(vec![])),
+            receiver(matches_info_vec.clone()),
+        );
 
         let mut widget_state = WidgetState::default();
         widget_state.list.select(Some(0));
 
-        assert_eq!(matches.state.matches_info_vec, matches_info_vec);
-        assert_eq!(matches.state.index, Some(0));
+        assert_eq!(matches.state.current.as_ref(), Some(&matches_info_vec[0]));
         assert_eq!(matches.state.state, widget_state);
 
         let matches = matches.prev_match().unwrap_matches();
 
-        assert_eq!(matches.state.index, Some(0));
+        assert_eq!(matches.state.current.as_ref(), Some(&matches_info_vec[0]));
         assert_eq!(matches.state.state.list.selected(), Some(0));
 
         let matches = matches.next_match().unwrap_matches();
 
-        assert_eq!(matches.state.index, Some(0));
+        assert_eq!(matches.state.current.as_ref(), Some(&matches_info_vec[0]));
         assert_eq!(matches.state.state.list.selected(), Some(1));
 
         let matches = matches.next_match().unwrap_matches();
 
-        assert_eq!(matches.state.index, Some(0));
+        assert_eq!(matches.state.current.as_ref(), Some(&matches_info_vec[0]));
         assert_eq!(matches.state.state.list.selected(), Some(1));
 
         let matches = matches.select().unwrap_matches();
 
-        assert_eq!(matches.state.index, Some(1));
+        assert_eq!(matches.state.current.as_ref(), Some(&matches_info_vec[1]));
         assert_eq!(matches.state.state.list.selected(), Some(0));
 
         // And it's done
@@ -381,13 +379,15 @@ mod tests {
     #[test]
     fn matches_abort() {
         let matches_info_vec = album_matches_info_vec();
-        let matches = AppMachine::matches(inner(music_hoard(vec![])), matches_info_vec.clone());
+        let matches = AppMachine::matches(
+            inner(music_hoard(vec![])),
+            receiver(matches_info_vec.clone()),
+        );
 
         let mut widget_state = WidgetState::default();
         widget_state.list.select(Some(0));
 
-        assert_eq!(matches.state.matches_info_vec, matches_info_vec);
-        assert_eq!(matches.state.index, Some(0));
+        assert_eq!(matches.state.current.as_ref(), Some(&matches_info_vec[0]));
         assert_eq!(matches.state.state, widget_state);
 
         matches.abort().unwrap_browse();
@@ -395,17 +395,16 @@ mod tests {
 
     #[test]
     fn matches_select_empty() {
-        let matches = AppMachine::matches(inner(music_hoard(vec![])), vec![]);
+        let matches = AppMachine::matches(inner(music_hoard(vec![])), receiver(vec![]));
 
-        assert_eq!(matches.state.matches_info_vec, vec![]);
-        assert_eq!(matches.state.index, None);
+        assert_eq!(matches.state.current, None);
 
         matches.select().unwrap_browse();
     }
 
     #[test]
     fn no_op() {
-        let matches = AppMachine::matches(inner(music_hoard(vec![])), vec![]);
+        let matches = AppMachine::matches(inner(music_hoard(vec![])), receiver(vec![]));
         let app = matches.no_op();
         app.unwrap_matches();
     }

src/tui/app/machine/mod.rs

@@ -143,6 +143,8 @@ impl<'a> From<&'a mut AppInner> for AppPublicInner<'a> {
 
 #[cfg(test)]
 mod tests {
+    use std::sync::mpsc;
+
     use musichoard::collection::Collection;
 
     use crate::tui::{
@@ -311,7 +313,8 @@ mod tests {
         let mut app = App::new(music_hoard_init(vec![]), mb_api());
         assert!(app.is_running());
 
-        app = AppMachine::matches(app.unwrap_browse().inner, vec![]).into();
+        let (_, rx) = mpsc::channel();
+        app = AppMachine::matches(app.unwrap_browse().inner, rx).into();
 
         let state = app.state();
         assert!(matches!(state, AppState::Matches(_)));

src/tui/app/mod.rs

@@ -165,22 +165,6 @@ impl<BS, IS, RS, SS, MS, ES, CS> AppState<BS, IS, RS, SS, MS, ES, CS> {
 mod tests {
     use super::*;
 
-    impl<'app> AppPublicMatchesInfo<'app> {
-        pub fn artist_ref(&self) -> &AppPublicArtistMatches<'app> {
-            match self {
-                Self::Artist(m) => m,
-                _ => panic!(),
-            }
-        }
-
-        pub fn album_ref(&self) -> &AppPublicAlbumMatches<'app> {
-            match self {
-                Self::Album(m) => m,
-                _ => panic!(),
-            }
-        }
-    }
-
     #[test]
     fn app_is_state() {
         let state = AppPublicState::Search("get rekt");