Adding a lobby scene (#34)

Closes #29

Reviewed-on: corentin/border-wars#34
Reviewed-by: Tipragot <contact@tipragot.fr>
Co-authored-by: CoCoSol007 <solois.corentin@gmail.com>
Co-committed-by: CoCoSol007 <solois.corentin@gmail.com>

crates/border-wars/src/scenes/lobby.rs

@@ -0,0 +1,38 @@
+//! The lobby of the game.
+
+use bevy::prelude::*;
+use bevy_egui::{egui, EguiContexts};
+
+use crate::CurrentScene;
+
+/// The plugin for the lobby.
+pub struct LobbyPlugin;
+
+impl Plugin for LobbyPlugin {
+    fn build(&self, app: &mut App) {
+        app.add_systems(Update, lobby_ui.run_if(in_state(CurrentScene::Lobby)));
+    }
+}
+
+/// Display the UI of the lobby.
+fn lobby_ui(mut ctx: EguiContexts, mut next_scene: ResMut<NextState<CurrentScene>>) {
+    egui::CentralPanel::default().show(ctx.ctx_mut(), |ui| {
+        ui.heading("Border Wars");
+
+        ui.separator();
+
+        ui.label("Game created");
+        ui.horizontal(|ui| {
+            ui.label("Game ID: ");
+            // TODO : get the game ID and display it.
+            ui.label("connection_string");
+        });
+
+        ui.separator();
+
+        if ui.button("Run the game").clicked() {
+            next_scene.set(CurrentScene::Game);
+            // TODO: run the game
+        }
+    });
+}

crates/border-wars/src/scenes/mod.rs

@@ -5,6 +5,7 @@ use bevy_egui::EguiPlugin;
 
 use crate::CurrentScene;
 
+pub mod lobby;
 pub mod menu;
 
 /// The plugin for all scenes.
@@ -14,6 +15,7 @@ impl Plugin for ScenesPlugin {
     fn build(&self, app: &mut App) {
         app.add_plugins(EguiPlugin)
             .add_state::<CurrentScene>()
-            .add_plugins(menu::MenuPlugin);
+            .add_plugins(menu::MenuPlugin)
+            .add_plugins(lobby::LobbyPlugin);
     }
 }