devex: migrate to vue-i18n (#4966)

* sample languages refactor

* feat: consistency + dedupe impl of i18n

* fix: broken imports

* fix: intl formatted component

* fix: use relative imports

* fix: imports

* fix: comment out incomplete locales + fix imports

* feat: cleanup

* fix: ui imports

* fix: lint

* fix: admonition import

* make footer a component, fix language reactivity

* make copyright notice untranslatable

---------

Co-authored-by: Calum H. <contact@cal.engineer>

packages/ui/src/composables/i18n.ts

@@ -0,0 +1,195 @@
+import IntlMessageFormat from 'intl-messageformat'
+import type { Ref } from 'vue'
+import type { CompileError, MessageCompiler, MessageContext } from 'vue-i18n'
+import { useI18n } from 'vue-i18n'
+
+export interface MessageDescriptor {
+	id: string
+	defaultMessage?: string
+	description?: string
+}
+
+export type MessageDescriptorMap<K extends string> = Record<K, MessageDescriptor>
+
+export type CrowdinMessages = Record<string, { message: string } | string>
+
+export function defineMessage<T extends MessageDescriptor>(descriptor: T): T {
+	return descriptor
+}
+
+export function defineMessages<K extends string, T extends MessageDescriptorMap<K>>(
+	descriptors: T,
+): T {
+	return descriptors
+}
+
+export interface LocaleDefinition {
+	code: string
+	name: string
+	dir?: 'ltr' | 'rtl'
+}
+
+export const LOCALES: LocaleDefinition[] = [
+	// { code: 'af-ZA', name: 'Afrikaans' },
+	// { code: 'ar-EG', name: 'العربية (مصر)', dir: 'rtl' },
+	// { code: 'ar-SA', name: 'العربية (السعودية)', dir: 'rtl' },
+	// { code: 'az-AZ', name: 'Azərbaycan' },
+	// { code: 'be-BY', name: 'Беларуская' },
+	// { code: 'bg-BG', name: 'Български' },
+	// { code: 'bn-BD', name: 'বাংলা' },
+	// { code: 'ca-ES', name: 'Català' },
+	// { code: 'ceb-PH', name: 'Cebuano' },
+	// { code: 'cs-CZ', name: 'Čeština' },
+	// { code: 'da-DK', name: 'Dansk' },
+	{ code: 'de-CH', name: 'Deutsch (Schweiz)' },
+	{ code: 'de-DE', name: 'Deutsch' },
+	// { code: 'el-GR', name: 'Ελληνικά' },
+	// { code: 'en-PT', name: 'Pirate English' },
+	// { code: 'en-UD', name: 'Upside Down' },
+	{ code: 'en-US', name: 'English (United States)' },
+	// { code: 'eo-UY', name: 'Esperanto' },
+	{ code: 'es-419', name: 'Español (Latinoamérica)' },
+	{ code: 'es-ES', name: 'Español (España)' },
+	// { code: 'et-EE', name: 'Eesti' },
+	// { code: 'fa-IR', name: 'فارسی', dir: 'rtl' },
+	// { code: 'fi-FI', name: 'Suomi' },
+	// { code: 'fil-PH', name: 'Filipino' },
+	{ code: 'fr-FR', name: 'Français' },
+	// { code: 'he-IL', name: 'עברית', dir: 'rtl' },
+	// { code: 'hi-IN', name: 'हिन्दी' },
+	// { code: 'hr-HR', name: 'Hrvatski' },
+	// { code: 'hu-HU', name: 'Magyar' },
+	// { code: 'id-ID', name: 'Bahasa Indonesia' },
+	// { code: 'is-IS', name: 'Íslenska' },
+	{ code: 'it-IT', name: 'Italiano' },
+	// { code: 'ja-JP', name: '日本語' },
+	// { code: 'kk-KZ', name: 'Қазақша' },
+	// { code: 'ko-KR', name: '한국어' },
+	// { code: 'ky-KG', name: 'Кыргызча' },
+	// { code: 'lol-US', name: 'LOLCAT' },
+	// { code: 'lt-LT', name: 'Lietuvių' },
+	// { code: 'lv-LV', name: 'Latviešu' },
+	// { code: 'ms-Arab', name: 'بهاس ملايو (جاوي)', dir: 'rtl' },
+	{ code: 'ms-MY', name: 'Bahasa Melayu' },
+	// { code: 'nl-NL', name: 'Nederlands' },
+	// { code: 'no-NO', name: 'Norsk' },
+	{ code: 'pl-PL', name: 'Polski' },
+	{ code: 'pt-BR', name: 'Português (Brasil)' },
+	{ code: 'pt-PT', name: 'Português (Portugal)' },
+	// { code: 'ro-RO', name: 'Română' },
+	{ code: 'ru-RU', name: 'Русский' },
+	// { code: 'sk-SK', name: 'Slovenčina' },
+	// { code: 'sl-SI', name: 'Slovenščina' },
+	// { code: 'sr-CS', name: 'Српски (ћирилица)' },
+	// { code: 'sr-SP', name: 'Srpski (latinica)' },
+	// { code: 'sv-SE', name: 'Svenska' },
+	// { code: 'th-TH', name: 'ไทย' },
+	// { code: 'tl-PH', name: 'Tagalog' },
+	{ code: 'tr-TR', name: 'Türkçe' },
+	// { code: 'tt-RU', name: 'Татарча' },
+	{ code: 'uk-UA', name: 'Українська' },
+	// { code: 'vi-VN', name: 'Tiếng Việt' },
+	{ code: 'zh-CN', name: '简体中文' },
+	{ code: 'zh-TW', name: '繁體中文' },
+]
+
+export function transformCrowdinMessages(messages: CrowdinMessages): Record<string, string> {
+	const result: Record<string, string> = {}
+	for (const [key, value] of Object.entries(messages)) {
+		if (typeof value === 'string') {
+			result[key] = value
+		} else if (typeof value === 'object' && value !== null && 'message' in value) {
+			result[key] = value.message
+		}
+	}
+	return result
+}
+
+const LOCALE_CODES = new Set(LOCALES.map((l) => l.code))
+
+/**
+ * Builds locale messages from glob-imported modules.
+ * Only includes locales that are defined in the LOCALES array.
+ * Usage: buildLocaleMessages(import.meta.glob('./locales/* /index.json', { eager: true }))
+ */
+export function buildLocaleMessages(
+	modules: Record<string, { default: CrowdinMessages }>,
+): Record<string, Record<string, string>> {
+	const messages: Record<string, Record<string, string>> = {}
+	for (const [path, module] of Object.entries(modules)) {
+		// Extract locale code from path like './locales/en-US/index.json'
+		const match = path.match(/\/([^/]+)\/index\.json$/)
+		if (match) {
+			const locale = match[1]
+			// Only include locales that are in our LOCALES list
+			if (LOCALE_CODES.has(locale)) {
+				messages[locale] = transformCrowdinMessages(module.default)
+			}
+		}
+	}
+	return messages
+}
+
+/**
+ * Creates a vue-i18n message compiler that uses IntlMessageFormat for ICU syntax support.
+ * This enables pluralization, select, and other ICU message features.
+ */
+export function createMessageCompiler(): MessageCompiler {
+	return (msg, { locale, key, onError }) => {
+		let messageString: string
+
+		if (typeof msg === 'string') {
+			messageString = msg
+		} else if (typeof msg === 'object' && msg !== null && 'message' in msg) {
+			messageString = (msg as { message: string }).message
+		} else {
+			onError?.(new Error('Invalid message format') as CompileError)
+			return () => key
+		}
+
+		try {
+			const formatter = new IntlMessageFormat(messageString, locale)
+			return (ctx: MessageContext) => {
+				try {
+					return formatter.format(ctx.values as Record<string, unknown>) as string
+				} catch {
+					return messageString
+				}
+			}
+		} catch (e) {
+			onError?.(e as CompileError)
+			return () => key
+		}
+	}
+}
+export interface VIntlFormatters {
+	formatMessage(descriptor: MessageDescriptor, values?: Record<string, unknown>): string
+}
+
+/**
+ * Composable that provides formatMessage() with the same API as @vintl/vintl.
+ * Uses vue-i18n's useI18n() under the hood.
+ */
+export function useVIntl(): VIntlFormatters & { locale: Ref<string> } {
+	const { t, locale } = useI18n()
+
+	function formatMessage(descriptor: MessageDescriptor, values?: Record<string, unknown>): string {
+		const key = descriptor.id
+		const translation = t(key, values ?? {})
+
+		if (translation && translation !== key) {
+			return translation as string
+		}
+
+		// Fallback to defaultMessage if key not found
+		const defaultMsg = descriptor.defaultMessage ?? key
+		try {
+			const formatter = new IntlMessageFormat(defaultMsg, locale.value)
+			return formatter.format(values ?? {}) as string
+		} catch {
+			return defaultMsg
+		}
+	}
+
+	return { formatMessage, locale }
+}