i18n

src/lib/i18n.ts

@@ -0,0 +1,81 @@
+/**
+ * Locale-aware routing helpers.
+ *
+ * SvelteKit's `resolve()` returns the language-neutral path a route lives at;
+ * every link has to go through `localizeHref()` on top of that, or clicking it
+ * would drop the visitor back into the base locale (the reroute hook in
+ * `src/hooks.ts` strips the prefix again on the way in).
+ */
+import { goto } from '$app/navigation';
+import { resolve } from '$app/paths';
+
+import { type Locale, deLocalizeHref, locales, localizeHref } from '$lib/paraglide/runtime';
+
+import type {
+	PathnameWithSearchOrHash,
+	RouteId,
+	RouteIdWithSearchOrHash,
+	RouteParams
+} from '$app/types';
+
+// Mirrors SvelteKit's own (non-exported) argument type for `resolve`, so a
+// route id still demands exactly the params that route declares.
+type StripSearchOrHash<T extends string> = T extends `${infer P}?${string}`
+	? P
+	: T extends `${infer P}#${string}`
+		? P
+		: T;
+
+type ResolveArgs<T extends RouteIdWithSearchOrHash | PathnameWithSearchOrHash> = T extends RouteId
+	? RouteParams<T> extends Record<string, never>
+		? [route: T]
+		: [route: T, params: RouteParams<T>]
+	: StripSearchOrHash<T> extends infer U extends RouteId
+		? RouteParams<U> extends Record<string, never>
+			? [route: T]
+			: [route: T, params: RouteParams<U>]
+		: [route: T];
+
+/**
+ * `resolve()` for the current locale. Mirrors SvelteKit's own signature, so
+ * route ids and their params keep being type-checked.
+ */
+export function href<T extends RouteIdWithSearchOrHash | PathnameWithSearchOrHash>(
+	...args: ResolveArgs<T>
+): string {
+	return localizeHref(resolve(...args));
+}
+
+/** Same as `href`, but forced into a specific locale. */
+export function hrefIn<T extends RouteIdWithSearchOrHash | PathnameWithSearchOrHash>(
+	locale: Locale,
+	...args: ResolveArgs<T>
+): string {
+	return localizeHref(resolve(...args), { locale });
+}
+
+/** `goto()` that keeps the visitor in their language. */
+export function gotoLocalized<T extends RouteIdWithSearchOrHash | PathnameWithSearchOrHash>(
+	...args: ResolveArgs<T>
+) {
+	return goto(href(...args));
+}
+
+/**
+ * The language-neutral path for a URL that still carries its locale prefix -
+ * what "which page am I on?" checks have to compare against.
+ */
+export function routePath(pathname: string): string {
+	return deLocalizeHref(pathname);
+}
+
+/** Display names for the language switcher, in the language itself. */
+export const LOCALE_LABELS: Record<Locale, string> = {
+	en: 'English',
+	de: 'Deutsch',
+	es: 'Español',
+	fr: 'Français',
+	it: 'Italiano'
+};
+
+export const LOCALE_LIST = locales;