Update with comments and type safety

src/locales/en/menu.ts

@@ -1,8 +1,13 @@
+/**
+ * The menu namespace holds most miscellaneous text that isn't directly part of the game's
+ * contents or directly related to Pokemon. This includes menu navigation, settings,
+ * account interactions, etc.
+ */
 export const menu = {
     "cancel": "Cancel",
     "continue": "Continue",
-    "newGame": "New Game",
-    "loadGame": "Load Game",
     "dailyRun": "Daily Run (Beta)",
+    "loadGame": "Load Game",
+    "newGame": "New Game",
     "selectGameMode": "Select a game mode."
 } as const;

src/locales/it/menu.ts

@@ -0,0 +1,8 @@
+export const menu = {
+    "cancel": "Annulla",
+    "continue": "Continua",
+    "newGame": "Nuova Partita",
+    "loadGame": "Carica Partita",
+    "dailyRun": "Corsa Giornaliera (Beta)",
+    "selectGameMode": "Seleziona una modalità di gioco."
+} as const;

src/phases.ts

@@ -57,7 +57,7 @@ import { SaveSlotUiMode } from "./ui/save-slot-select-ui-handler";
 import { fetchDailyRunSeed, getDailyRunStarters } from "./data/daily-run";
 import { GameModes, gameModes } from "./game-mode";
 import { getPokemonSpecies, speciesStarters } from "./data/pokemon-species";
-import { default as i18next, menuNS }from './plugins/i18n';
+import i18next from './plugins/i18n';
 
 export class LoginPhase extends Phase {
   private showText: boolean;
@@ -174,7 +174,7 @@ export class TitlePhase extends Phase {
     const options: OptionSelectItem[] = [];
     if (loggedInUser.lastSessionSlot > -1) {
       options.push({
-        label: i18next.t('continue', {ns: menuNS}),
+        label: i18next.t('menu:continue'),
         handler: () => this.loadSaveSlot(this.lastSessionData ? -1 : loggedInUser.lastSessionSlot)
       });
     }

src/plugins/i18n.ts

@@ -1,17 +1,42 @@
 import i18next from 'i18next';
 import { menu as enMenu } from '../locales/en/menu';
+import { menu as itMenu } from '../locales/it/menu';
 
-export const menuNS = 'menu';
+const DEFAULT_LANGUAGE_OVERRIDE = '';
+
+/**
+ * i18next is a localization library for maintaining and using translation resources.
+ * 
+ * Q: How do I add a new language?
+ * A: To add a new language, create a new folder in the locales directory with the language code.
+ *    Each language folder should contain a file for each namespace (ex. menu.ts) with the translations.
+ * 
+ * Q: How do I add a new namespace?
+ * A: To add a new namespace, create a new file in each language folder with the translations.
+ *    Then update the `resources` field in the init() call and the CustomTypeOptions interface.
+ */
 
 i18next.init({
-  lng: 'en', // Default language
-  fallbackLng: 'en', // Fallback language
-  debug: true, // Enable debug mode (optional)
+  lng: DEFAULT_LANGUAGE_OVERRIDE ? DEFAULT_LANGUAGE_OVERRIDE : 'en',
+  fallbackLng: 'en',
+  debug: true,
   resources: {
     en: {
       menu: enMenu,
     },
+    it: {
+      menu: itMenu,
+    }
   },
 });
 
+// Module declared to make referencing keys in the localization files type-safe.
+declare module 'i18next' {
+  interface CustomTypeOptions {
+    resources: {
+      menu: typeof enMenu;
+    };
+  }
+}
+
 export default i18next;