feat: defind detection config and use middleware

Author: caohuilin

packages/runtime/plugin-i18n/src/runtime/i18n/detection/config.ts

@@ -0,0 +1,29 @@
+import type { RuntimeContext } from '@modern-js/runtime';
+import { deepMerge } from '../../../shared/deepMerge';
+import type { LanguageDetectorOptions } from '../instance';
+
+export const DEFAULT_I18NEXT_DETECTION_OPTIONS = {
+  caches: ['cookie', 'localStorage'],
+  order: [
+    'querystring',
+    'cookie',
+    'localStorage',
+    'header',
+    'navigator',
+    'htmlTag',
+    'path',
+    'subdomain',
+  ],
+  cookieMinutes: 60 * 24 * 365,
+  lookupQuerystring: 'lng',
+  lookupCookie: 'i18next',
+  lookupLocalStorage: 'i18nextLng',
+  lookupHeader: 'accept-language',
+};
+
+export function mergeDetectionOptions(
+  userOptions?: LanguageDetectorOptions,
+  defaultOptions: LanguageDetectorOptions = DEFAULT_I18NEXT_DETECTION_OPTIONS,
+): LanguageDetectorOptions {
+  return deepMerge(defaultOptions, userOptions);
+}

packages/runtime/plugin-i18n/src/runtime/i18n/detection/middleware.node.ts

@@ -0,0 +1,29 @@
+import { LanguageDetector } from 'i18next-http-middleware';
+import type { I18nInstance } from '../instance';
+
+export const useI18nextLanguageDetector = (i18nInstance: I18nInstance) => {
+  return i18nInstance.use(LanguageDetector);
+};
+
+export const detectLanguage = (
+  i18nInstance: I18nInstance,
+  request?: any,
+): string | undefined => {
+  const detector = i18nInstance.services?.languageDetector;
+  if (detector && typeof detector.detect === 'function' && request) {
+    try {
+      const result = detector.detect(request, {});
+      // detector.detect() can return string | string[] | undefined
+      if (typeof result === 'string') {
+        return result;
+      }
+      if (Array.isArray(result) && result.length > 0) {
+        return result[0];
+      }
+      return undefined;
+    } catch (error) {
+      return undefined;
+    }
+  }
+  return undefined;
+};

packages/runtime/plugin-i18n/src/runtime/i18n/detection/middleware.ts

@@ -0,0 +1,30 @@
+import LanguageDetector from 'i18next-browser-languagedetector';
+import type { I18nInstance } from '../instance';
+
+export const useI18nextLanguageDetector = (i18nInstance: I18nInstance) => {
+  return i18nInstance.use(LanguageDetector);
+};
+
+export const detectLanguage = (
+  i18nInstance: I18nInstance,
+  _request?: any,
+): string | undefined => {
+  // Access the detector from i18next services
+  // The detector is registered via useI18nextLanguageDetector() and initialized in init()
+  const detector = i18nInstance.services?.languageDetector;
+  if (detector && typeof detector.detect === 'function') {
+    try {
+      const result = detector.detect();
+      // detector.detect() can return string | string[] | undefined
+      if (typeof result === 'string') {
+        return result;
+      }
+      if (Array.isArray(result) && result.length > 0) {
+        return result[0];
+      }
+    } catch (error) {
+      return undefined;
+    }
+  }
+  return undefined;
+};

packages/runtime/plugin-i18n/src/runtime/i18n/instance.ts

@@ -7,13 +7,34 @@ export interface I18nInstance {
   use: (plugin: any) => void;
   createInstance: (options?: I18nInitOptions) => I18nInstance;
   cloneInstance?: () => I18nInstance; // ssr need
+  services?: {
+    languageDetector?: {
+      detect: (request?: any, options?: any) => string | string[] | undefined;
+      [key: string]: any;
+    };
+    [key: string]: any;
+  };
+}
+
+type LanguageDetectorOrder = string[];
+type LanguageDetectorCaches = boolean | string[];
+export interface LanguageDetectorOptions {
+  order?: LanguageDetectorOrder;
+  lookupQuerystring?: string;
+  lookupCookie?: string;
+  lookupSession?: string;
+  lookupFromPathIndex?: number;
+  caches?: LanguageDetectorCaches;
+  cookieExpirationDate?: Date;
+  cookieDomain?: string;
 }
 
 export type I18nInitOptions = {
   lng?: string;
   fallbackLng?: string;
   supportedLngs?: string[];
   initImmediate?: boolean;
+  detection?: LanguageDetectorOptions;
 };
 
 export function isI18nInstance(obj: any): obj is I18nInstance {