fix: UI for leaving online game when disconnected (#1002)

During a game, if all other players have been disconnected, UI pop-up
will notify player providing button to return to main menu.

If one player but not all have disconnected, going to have game keep
going / figure out how to handle this separately.

Relates to #994, will not fix
anything, but if hung due to disconnect, will inform player at least.

Depends on fishfolk/bones#409, CI will fail
until merged + update bones version.

assets/locales/en-US/network-game.ftl

@@ -20,3 +20,8 @@ connected-and-querying = Connected
 waiting-for-players = Waiting for Players: { $current } / { $total }
 match-ready = Match Ready!
 error = Error
+
+# Pop-ups
+disconnected = Disconnected
+disconnected-from-all = Disconnected from all other players.
+exit-match = Exit Match

src/main.rs

@@ -185,6 +185,11 @@ fn main() {
         .create(SessionNames::SCORING)
         .install_plugin(ui::scoring::session_plugin);
 
+    // session for pop-ups / nofication UI
+    game.sessions
+        .create(SessionNames::NOTIFICATION)
+        .install_plugin(ui::notification::session_plugin);
+
     // Create a bevy renderer for the bones game and run it.
     BonesBevyRenderer {
         game,

src/sessions.rs

@@ -9,6 +9,7 @@ impl SessionNames {
     pub const PAUSE_MENU: &'static str = "pause_menu";
     pub const PROFILER: &'static str = "profiler";
     pub const SCORING: &'static str = "scoring";
+    pub const NOTIFICATION: &'static str = "notification";
 }
 
 pub trait SessionExt {

src/ui.rs

@@ -2,6 +2,7 @@ use crate::prelude::*;
 
 pub mod main_menu;
 pub mod map_select;
+pub mod notification;
 pub mod pause_menu;
 pub mod player_image;
 pub mod scoring;

src/ui/notification.rs

@@ -0,0 +1,105 @@
+use std::borrow::BorrowMut;
+
+use crate::prelude::*;
+
+#[allow(unused_variables)]
+pub fn session_plugin(session: &mut Session) {
+    #[cfg(not(target_arch = "wasm32"))]
+    session.add_system_to_stage(Update, network_disconnect_notify);
+}
+
+pub fn network_disconnect_notify(
+    meta: Root<GameMeta>,
+    ctx: Res<EguiCtx>,
+    mut sessions: ResMut<Sessions>,
+    world: &World,
+) {
+    let sessions = sessions.borrow_mut();
+    #[allow(unused_assignments, unused_mut)]
+    let mut all_players_disconnected = false;
+
+    #[cfg(not(target_arch = "wasm32"))]
+    {
+        all_players_disconnected = if let Some(game_session) = sessions.get(SessionNames::GAME) {
+            if let Some(disconnected_players) =
+                game_session.world.resources.get::<DisconnectedPlayers>()
+            {
+                // Determine if all remote players have been disconnected
+                // (Disconnected players should be player count - 1, can not have local player)
+                let player_indices = game_session.world.components.get::<PlayerIdx>().borrow();
+
+                !disconnected_players.disconnected_players.is_empty()
+                    && player_indices.bitset().bit_count() - 1
+                        == disconnected_players.disconnected_players.len()
+            } else {
+                false
+            }
+        } else {
+            false
+        };
+    }
+
+    if all_players_disconnected {
+        egui::CentralPanel::default()
+            .frame(egui::Frame::none())
+            .show(&ctx, |ui| {
+                ui.vertical_centered(|ui| {
+                    // Calculate a margin
+                    let screen_rect = ui.max_rect();
+                    let outer_margin = screen_rect.size() * 0.10;
+                    let outer_margin = egui::Margin {
+                        left: outer_margin.x,
+                        right: outer_margin.x,
+                        top: outer_margin.y * 3.0,
+                        bottom: outer_margin.y,
+                    };
+
+                    BorderedFrame::new(&meta.theme.panel.border)
+                        .margin(outer_margin)
+                        .padding(meta.theme.panel.padding)
+                        .show(ui, |ui| {
+                            world.run_system(
+                                network_disconnect_notify_ui,
+                                (ui, sessions.borrow_mut()),
+                            )
+                        });
+                });
+            });
+    }
+}
+
+fn network_disconnect_notify_ui(
+    mut param: In<(&mut egui::Ui, &mut Sessions)>,
+    localization: Localization<GameMeta>,
+    meta: Root<GameMeta>,
+) {
+    let (ui, sessions) = &mut *param;
+    ui.vertical_centered(|ui| {
+        ui.label(
+            meta.theme
+                .font_styles
+                .heading
+                .rich(localization.get("disconnected")),
+        );
+
+        ui.add_space(meta.theme.font_styles.normal.size);
+        ui.label(
+            meta.theme
+                .font_styles
+                .normal
+                .rich(localization.get("disconnected-from-all")),
+        );
+        ui.add_space(meta.theme.font_styles.normal.size);
+
+        if BorderedButton::themed(&meta.theme.buttons.normal, localization.get("exit-match"))
+            .show(ui)
+            .focus_by_default(ui)
+            .clicked()
+        {
+            sessions.add_command(Box::new(move |sessions: &mut Sessions| {
+                sessions.end_game();
+                sessions.start_menu();
+            }));
+        }
+    });
+}