feat: 全站多语言支持 (i18n)，lang=en 显示英文，其余默认中文

新增 src/lib/locale.ts 作为统一多语言入口，覆盖前台支付链路、
管理后台、API/服务层错误文案，共 35 个文件。URL 参数 lang 全链路透传，
包括 Stripe return_url、页面跳转、layout html lang 属性等。

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

src/lib/admin-auth.ts

@@ -1,6 +1,7 @@
 import { NextRequest, NextResponse } from 'next/server';
 import { getEnv } from '@/lib/config';
 import crypto from 'crypto';
+import { resolveLocale } from '@/lib/locale';
 
 function isLocalAdminToken(token: string): boolean {
   const env = getEnv();
@@ -56,6 +57,7 @@ export async function verifyAdminToken(request: NextRequest): Promise<boolean> {
   return isSub2ApiAdmin(token);
 }
 
-export function unauthorizedResponse() {
-  return NextResponse.json({ error: '未授权' }, { status: 401 });
+export function unauthorizedResponse(request?: NextRequest) {
+  const locale = resolveLocale(request?.nextUrl.searchParams.get('lang'));
+  return NextResponse.json({ error: locale === 'en' ? 'Unauthorized' : '未授权' }, { status: 401 });
 }

src/lib/locale.ts

@@ -0,0 +1,20 @@
+export type Locale = 'zh' | 'en';
+
+export function resolveLocale(lang: string | null | undefined): Locale {
+  return lang?.trim().toLowerCase() === 'en' ? 'en' : 'zh';
+}
+
+export function isEnglish(locale: Locale): boolean {
+  return locale === 'en';
+}
+
+export function pickLocaleText<T>(locale: Locale, zh: T, en: T): T {
+  return locale === 'en' ? en : zh;
+}
+
+export function applyLocaleToSearchParams(params: URLSearchParams, locale: Locale): URLSearchParams {
+  if (locale === 'en') {
+    params.set('lang', 'en');
+  }
+  return params;
+}

src/lib/order/service.ts

@@ -9,9 +9,14 @@ import type { PaymentType, PaymentNotification } from '@/lib/payment';
 import { getUser, createAndRedeem, subtractBalance, addBalance } from '@/lib/sub2api/client';
 import { Prisma } from '@prisma/client';
 import { deriveOrderState, isRefundStatus } from './status';
+import { pickLocaleText, type Locale } from '@/lib/locale';
 
 const MAX_PENDING_ORDERS = 3;
 
+function message(locale: Locale, zh: string, en: string): string {
+  return pickLocaleText(locale, zh, en);
+}
+
 export interface CreateOrderInput {
   userId: number;
   amount: number;
@@ -20,6 +25,7 @@ export interface CreateOrderInput {
   isMobile?: boolean;
   srcHost?: string;
   srcUrl?: string;
+  locale?: Locale;
 }
 
 export interface CreateOrderResult {
@@ -39,17 +45,22 @@ export interface CreateOrderResult {
 
 export async function createOrder(input: CreateOrderInput): Promise<CreateOrderResult> {
   const env = getEnv();
+  const locale = input.locale ?? 'zh';
 
   const user = await getUser(input.userId);
   if (user.status !== 'active') {
-    throw new OrderError('USER_INACTIVE', 'User account is disabled', 422);
+    throw new OrderError('USER_INACTIVE', message(locale, '用户账号已被禁用', 'User account is disabled'), 422);
   }
 
   const pendingCount = await prisma.order.count({
     where: { userId: input.userId, status: ORDER_STATUS.PENDING },
   });
   if (pendingCount >= MAX_PENDING_ORDERS) {
-    throw new OrderError('TOO_MANY_PENDING', `Too many pending orders (${MAX_PENDING_ORDERS})`, 429);
+    throw new OrderError(
+      'TOO_MANY_PENDING',
+      message(locale, `待支付订单过多（最多 ${MAX_PENDING_ORDERS} 笔）`, `Too many pending orders (${MAX_PENDING_ORDERS})`),
+      429,
+    );
   }
 
   // 每日累计充值限额校验（0 = 不限制）
@@ -67,7 +78,15 @@ export async function createOrder(input: CreateOrderInput): Promise<CreateOrderR
     const alreadyPaid = Number(dailyAgg._sum.amount ?? 0);
     if (alreadyPaid + input.amount > env.MAX_DAILY_RECHARGE_AMOUNT) {
       const remaining = Math.max(0, env.MAX_DAILY_RECHARGE_AMOUNT - alreadyPaid);
-      throw new OrderError('DAILY_LIMIT_EXCEEDED', `今日累计充值已达上限，剩余可充值 ${remaining.toFixed(2)} 元`, 429);
+      throw new OrderError(
+        'DAILY_LIMIT_EXCEEDED',
+        message(
+          locale,
+          `今日累计充值已达上限，剩余可充值 ${remaining.toFixed(2)} 元`,
+          `Daily recharge limit reached. Remaining amount: ${remaining.toFixed(2)} CNY`,
+        ),
+        429,
+      );
     }
   }
 
@@ -90,8 +109,16 @@ export async function createOrder(input: CreateOrderInput): Promise<CreateOrderR
       throw new OrderError(
         'METHOD_DAILY_LIMIT_EXCEEDED',
         remaining > 0
-          ? `${input.paymentType} 今日剩余额度 ${remaining.toFixed(2)} 元，请减少充值金额或使用其他支付方式`
-          : `${input.paymentType} 今日充值额度已满，请使用其他支付方式`,
+          ? message(
+              locale,
+              `${input.paymentType} 今日剩余额度 ${remaining.toFixed(2)} 元，请减少充值金额或使用其他支付方式`,
+              `${input.paymentType} remaining daily quota: ${remaining.toFixed(2)} CNY. Reduce the amount or use another payment method`,
+            )
+          : message(
+              locale,
+              `${input.paymentType} 今日充值额度已满，请使用其他支付方式`,
+              `${input.paymentType} daily quota is full. Please use another payment method`,
+            ),
         429,
       );
     }
@@ -195,9 +222,17 @@ export async function createOrder(input: CreateOrderInput): Promise<CreateOrderR
     const msg = error instanceof Error ? error.message : String(error);
     console.error(`Payment gateway error (${input.paymentType}):`, error);
     if (msg.includes('environment variables') || msg.includes('not configured') || msg.includes('not found')) {
-      throw new OrderError('PAYMENT_GATEWAY_ERROR', `支付渠道（${input.paymentType}）暂未配置，请联系管理员`, 503);
+      throw new OrderError(
+        'PAYMENT_GATEWAY_ERROR',
+        message(locale, `支付渠道（${input.paymentType}）暂未配置，请联系管理员`, `Payment method (${input.paymentType}) is not configured. Please contact the administrator`),
+        503,
+      );
     }
-    throw new OrderError('PAYMENT_GATEWAY_ERROR', '支付渠道暂时不可用，请稍后重试或更换支付方式', 502);
+    throw new OrderError(
+      'PAYMENT_GATEWAY_ERROR',
+      message(locale, '支付渠道暂时不可用，请稍后重试或更换支付方式', 'Payment method is temporarily unavailable. Please try again later or use another payment method'),
+      502,
+    );
   }
 }
 
@@ -268,15 +303,16 @@ export async function cancelOrderCore(options: {
   return 'cancelled';
 }
 
-export async function cancelOrder(orderId: string, userId: number): Promise<CancelOutcome> {
+export async function cancelOrder(orderId: string, userId: number, locale: Locale = 'zh'): Promise<CancelOutcome> {
   const order = await prisma.order.findUnique({
     where: { id: orderId },
     select: { id: true, userId: true, status: true, paymentTradeNo: true, paymentType: true },
   });
 
-  if (!order) throw new OrderError('NOT_FOUND', 'Order not found', 404);
-  if (order.userId !== userId) throw new OrderError('FORBIDDEN', 'Forbidden', 403);
-  if (order.status !== ORDER_STATUS.PENDING) throw new OrderError('INVALID_STATUS', 'Order cannot be cancelled', 400);
+  if (!order) throw new OrderError('NOT_FOUND', message(locale, '订单不存在', 'Order not found'), 404);
+  if (order.userId !== userId) throw new OrderError('FORBIDDEN', message(locale, '无权操作该订单', 'Forbidden'), 403);
+  if (order.status !== ORDER_STATUS.PENDING)
+    throw new OrderError('INVALID_STATUS', message(locale, '订单当前状态不可取消', 'Order cannot be cancelled'), 400);
 
   return cancelOrderCore({
     orderId: order.id,
@@ -284,18 +320,19 @@ export async function cancelOrder(orderId: string, userId: number): Promise<Canc
     paymentType: order.paymentType,
     finalStatus: ORDER_STATUS.CANCELLED,
     operator: `user:${userId}`,
-    auditDetail: 'User cancelled order',
+    auditDetail: message(locale, '用户取消订单', 'User cancelled order'),
   });
 }
 
-export async function adminCancelOrder(orderId: string): Promise<CancelOutcome> {
+export async function adminCancelOrder(orderId: string, locale: Locale = 'zh'): Promise<CancelOutcome> {
   const order = await prisma.order.findUnique({
     where: { id: orderId },
     select: { id: true, status: true, paymentTradeNo: true, paymentType: true },
   });
 
-  if (!order) throw new OrderError('NOT_FOUND', 'Order not found', 404);
-  if (order.status !== ORDER_STATUS.PENDING) throw new OrderError('INVALID_STATUS', 'Order cannot be cancelled', 400);
+  if (!order) throw new OrderError('NOT_FOUND', message(locale, '订单不存在', 'Order not found'), 404);
+  if (order.status !== ORDER_STATUS.PENDING)
+    throw new OrderError('INVALID_STATUS', message(locale, '订单当前状态不可取消', 'Order cannot be cancelled'), 400);
 
   return cancelOrderCore({
     orderId: order.id,
@@ -303,7 +340,7 @@ export async function adminCancelOrder(orderId: string): Promise<CancelOutcome>
     paymentType: order.paymentType,
     finalStatus: ORDER_STATUS.CANCELLED,
     operator: 'admin',
-    auditDetail: 'Admin cancelled order',
+    auditDetail: message(locale, '管理员取消订单', 'Admin cancelled order'),
   });
 }
 
@@ -531,13 +568,13 @@ export async function executeRecharge(orderId: string): Promise<void> {
   }
 }
 
-function assertRetryAllowed(order: { status: string; paidAt: Date | null }): void {
+function assertRetryAllowed(order: { status: string; paidAt: Date | null }, locale: Locale): void {
   if (!order.paidAt) {
-    throw new OrderError('INVALID_STATUS', 'Order is not paid, retry denied', 400);
+    throw new OrderError('INVALID_STATUS', message(locale, '订单未支付，不允许重试', 'Order is not paid, retry denied'), 400);
   }
 
   if (isRefundStatus(order.status)) {
-    throw new OrderError('INVALID_STATUS', 'Refund-related order cannot retry', 400);
+    throw new OrderError('INVALID_STATUS', message(locale, '退款相关订单不允许重试', 'Refund-related order cannot retry'), 400);
   }
 
   if (order.status === ORDER_STATUS.FAILED || order.status === ORDER_STATUS.PAID) {
@@ -545,17 +582,17 @@ function assertRetryAllowed(order: { status: string; paidAt: Date | null }): voi
   }
 
   if (order.status === ORDER_STATUS.RECHARGING) {
-    throw new OrderError('CONFLICT', 'Order is recharging, retry later', 409);
+    throw new OrderError('CONFLICT', message(locale, '订单正在充值中，请稍后重试', 'Order is recharging, retry later'), 409);
   }
 
   if (order.status === ORDER_STATUS.COMPLETED) {
-    throw new OrderError('INVALID_STATUS', 'Order already completed', 400);
+    throw new OrderError('INVALID_STATUS', message(locale, '订单已完成', 'Order already completed'), 400);
   }
 
-  throw new OrderError('INVALID_STATUS', 'Only paid and failed orders can retry', 400);
+  throw new OrderError('INVALID_STATUS', message(locale, '仅已支付和失败订单允许重试', 'Only paid and failed orders can retry'), 400);
 }
 
-export async function retryRecharge(orderId: string): Promise<void> {
+export async function retryRecharge(orderId: string, locale: Locale = 'zh'): Promise<void> {
   const order = await prisma.order.findUnique({
     where: { id: orderId },
     select: {
@@ -567,10 +604,10 @@ export async function retryRecharge(orderId: string): Promise<void> {
   });
 
   if (!order) {
-    throw new OrderError('NOT_FOUND', 'Order not found', 404);
+    throw new OrderError('NOT_FOUND', message(locale, '订单不存在', 'Order not found'), 404);
   }
 
-  assertRetryAllowed(order);
+  assertRetryAllowed(order, locale);
 
   const result = await prisma.order.updateMany({
     where: {
@@ -592,30 +629,30 @@ export async function retryRecharge(orderId: string): Promise<void> {
     });
 
     if (!latest) {
-      throw new OrderError('NOT_FOUND', 'Order not found', 404);
+      throw new OrderError('NOT_FOUND', message(locale, '订单不存在', 'Order not found'), 404);
     }
 
     const derived = deriveOrderState(latest);
     if (derived.rechargeStatus === 'recharging' || latest.status === ORDER_STATUS.PAID) {
-      throw new OrderError('CONFLICT', 'Order is recharging, retry later', 409);
+      throw new OrderError('CONFLICT', message(locale, '订单正在充值中，请稍后重试', 'Order is recharging, retry later'), 409);
     }
 
     if (derived.rechargeStatus === 'success') {
-      throw new OrderError('INVALID_STATUS', 'Order already completed', 400);
+      throw new OrderError('INVALID_STATUS', message(locale, '订单已完成', 'Order already completed'), 400);
     }
 
     if (isRefundStatus(latest.status)) {
-      throw new OrderError('INVALID_STATUS', 'Refund-related order cannot retry', 400);
+      throw new OrderError('INVALID_STATUS', message(locale, '退款相关订单不允许重试', 'Refund-related order cannot retry'), 400);
     }
 
-    throw new OrderError('CONFLICT', 'Order status changed, refresh and retry', 409);
+    throw new OrderError('CONFLICT', message(locale, '订单状态已变更，请刷新后重试', 'Order status changed, refresh and retry'), 409);
   }
 
   await prisma.auditLog.create({
     data: {
       orderId,
       action: 'RECHARGE_RETRY',
-      detail: 'Admin manual retry recharge',
+      detail: message(locale, '管理员手动重试充值', 'Admin manual retry recharge'),
       operator: 'admin',
     },
   });
@@ -627,6 +664,7 @@ export interface RefundInput {
   orderId: string;
   reason?: string;
   force?: boolean;
+  locale?: Locale;
 }
 
 export interface RefundResult {
@@ -636,10 +674,11 @@ export interface RefundResult {
 }
 
 export async function processRefund(input: RefundInput): Promise<RefundResult> {
+  const locale = input.locale ?? 'zh';
   const order = await prisma.order.findUnique({ where: { id: input.orderId } });
-  if (!order) throw new OrderError('NOT_FOUND', 'Order not found', 404);
+  if (!order) throw new OrderError('NOT_FOUND', message(locale, '订单不存在', 'Order not found'), 404);
   if (order.status !== ORDER_STATUS.COMPLETED) {
-    throw new OrderError('INVALID_STATUS', 'Only completed orders can be refunded', 400);
+    throw new OrderError('INVALID_STATUS', message(locale, '仅已完成订单允许退款', 'Only completed orders can be refunded'), 400);
   }
 
   const rechargeAmount = Number(order.amount);
@@ -651,14 +690,18 @@ export async function processRefund(input: RefundInput): Promise<RefundResult> {
       if (user.balance < rechargeAmount) {
         return {
           success: false,
-          warning: `User balance ${user.balance} is lower than refund ${rechargeAmount}`,
+          warning: message(
+            locale,
+            `用户余额 ${user.balance} 小于需退款的充值金额 ${rechargeAmount}`,
+            `User balance ${user.balance} is lower than refund ${rechargeAmount}`,
+          ),
           requireForce: true,
         };
       }
     } catch {
       return {
         success: false,
-        warning: 'Cannot fetch user balance, use force=true',
+        warning: message(locale, '无法获取用户余额，请使用 force=true', 'Cannot fetch user balance, use force=true'),
         requireForce: true,
       };
     }
@@ -669,7 +712,7 @@ export async function processRefund(input: RefundInput): Promise<RefundResult> {
     data: { status: ORDER_STATUS.REFUNDING },
   });
   if (lockResult.count === 0) {
-    throw new OrderError('CONFLICT', 'Order status changed, refresh and retry', 409);
+    throw new OrderError('CONFLICT', message(locale, '订单状态已变更，请刷新后重试', 'Order status changed, refresh and retry'), 409);
   }
 
   try {

src/lib/pay-utils.ts

@@ -4,6 +4,7 @@ import {
   PAYMENT_PREFIX,
   REDIRECT_PAYMENT_TYPES,
 } from './constants';
+import type { Locale } from './locale';
 
 export interface UserInfo {
   id?: number;
@@ -21,73 +22,90 @@ export interface MyOrder {
 
 export type OrderStatusFilter = 'ALL' | 'PENDING' | 'PAID' | 'COMPLETED' | 'CANCELLED' | 'EXPIRED' | 'FAILED';
 
-export const STATUS_TEXT_MAP: Record<string, string> = {
-  [ORDER_STATUS.PENDING]: '待支付',
-  [ORDER_STATUS.PAID]: '已支付',
-  [ORDER_STATUS.RECHARGING]: '充值中',
-  [ORDER_STATUS.COMPLETED]: '已完成',
-  [ORDER_STATUS.EXPIRED]: '已超时',
-  [ORDER_STATUS.CANCELLED]: '已取消',
-  [ORDER_STATUS.FAILED]: '失败',
-  [ORDER_STATUS.REFUNDING]: '退款中',
-  [ORDER_STATUS.REFUNDED]: '已退款',
-  [ORDER_STATUS.REFUND_FAILED]: '退款失败',
+const STATUS_TEXT_MAP: Record<Locale, Record<string, string>> = {
+  zh: {
+    [ORDER_STATUS.PENDING]: '待支付',
+    [ORDER_STATUS.PAID]: '已支付',
+    [ORDER_STATUS.RECHARGING]: '充值中',
+    [ORDER_STATUS.COMPLETED]: '已完成',
+    [ORDER_STATUS.EXPIRED]: '已超时',
+    [ORDER_STATUS.CANCELLED]: '已取消',
+    [ORDER_STATUS.FAILED]: '失败',
+    [ORDER_STATUS.REFUNDING]: '退款中',
+    [ORDER_STATUS.REFUNDED]: '已退款',
+    [ORDER_STATUS.REFUND_FAILED]: '退款失败',
+  },
+  en: {
+    [ORDER_STATUS.PENDING]: 'Pending',
+    [ORDER_STATUS.PAID]: 'Paid',
+    [ORDER_STATUS.RECHARGING]: 'Recharging',
+    [ORDER_STATUS.COMPLETED]: 'Completed',
+    [ORDER_STATUS.EXPIRED]: 'Expired',
+    [ORDER_STATUS.CANCELLED]: 'Cancelled',
+    [ORDER_STATUS.FAILED]: 'Failed',
+    [ORDER_STATUS.REFUNDING]: 'Refunding',
+    [ORDER_STATUS.REFUNDED]: 'Refunded',
+    [ORDER_STATUS.REFUND_FAILED]: 'Refund failed',
+  },
 };
 
-export const FILTER_OPTIONS: { key: OrderStatusFilter; label: string }[] = [
-  { key: 'ALL', label: '全部' },
-  { key: 'PENDING', label: '待支付' },
-  { key: 'COMPLETED', label: '已完成' },
-  { key: 'CANCELLED', label: '已取消' },
-  { key: 'EXPIRED', label: '已超时' },
-];
+const FILTER_OPTIONS_MAP: Record<Locale, { key: OrderStatusFilter; label: string }[]> = {
+  zh: [
+    { key: 'ALL', label: '全部' },
+    { key: 'PENDING', label: '待支付' },
+    { key: 'COMPLETED', label: '已完成' },
+    { key: 'CANCELLED', label: '已取消' },
+    { key: 'EXPIRED', label: '已超时' },
+  ],
+  en: [
+    { key: 'ALL', label: 'All' },
+    { key: 'PENDING', label: 'Pending' },
+    { key: 'COMPLETED', label: 'Completed' },
+    { key: 'CANCELLED', label: 'Cancelled' },
+    { key: 'EXPIRED', label: 'Expired' },
+  ],
+};
+
+export function getFilterOptions(locale: Locale = 'zh'): { key: OrderStatusFilter; label: string }[] {
+  return FILTER_OPTIONS_MAP[locale];
+}
 
 export function detectDeviceIsMobile(): boolean {
   if (typeof window === 'undefined') return false;
 
-  // 1. 现代 API（Chromium 系浏览器，最准确）
   const uad = (navigator as Navigator & { userAgentData?: { mobile: boolean } }).userAgentData;
   if (uad !== undefined) return uad.mobile;
 
-  // 2. UA 正则兜底（Safari / Firefox 等）
   const ua = navigator.userAgent || '';
   const mobileUA = /Android|webOS|iPhone|iPad|iPod|BlackBerry|IEMobile|Windows Phone|Mobile/i.test(ua);
   if (mobileUA) return true;
 
-  // 3. 触控 + 小屏兜底（新版 iPad UA 伪装成 Mac 的情况）
   const smallPhysicalScreen = Math.min(window.screen.width, window.screen.height) <= 768;
   const touchCapable = navigator.maxTouchPoints > 1;
   return touchCapable && smallPhysicalScreen;
 }
 
-export function formatStatus(status: string): string {
-  return STATUS_TEXT_MAP[status] || status;
+export function formatStatus(status: string, locale: Locale = 'zh'): string {
+  return STATUS_TEXT_MAP[locale][status] || status;
 }
 
-export function formatCreatedAt(value: string): string {
+export function formatCreatedAt(value: string, locale: Locale = 'zh'): string {
   const date = new Date(value);
   if (Number.isNaN(date.getTime())) return value;
-  return date.toLocaleString();
+  return date.toLocaleString(locale === 'en' ? 'en-US' : 'zh-CN');
 }
 
 export interface PaymentTypeMeta {
-  /** 支付渠道名（用户看到的：支付宝 / 微信支付 / Stripe） */
   label: string;
-  /** 选择器中的辅助说明（易支付 / 官方 / 信用卡 / 借记卡） */
   sublabel?: string;
-  /** 提供商名称（易支付 / 支付宝 / 微信支付 / Stripe） */
   provider: string;
   color: string;
   selectedBorder: string;
   selectedBg: string;
-  /** 暗色模式选中背景 */
   selectedBgDark: string;
   iconBg: string;
-  /** 图标路径（Stripe 不使用外部图标） */
   iconSrc?: string;
-  /** 图表条形颜色 class */
   chartBar: { light: string; dark: string };
-  /** 按钮颜色 class（含 hover/active 状态） */
   buttonClass: string;
 }
 
@@ -153,26 +171,51 @@ export const PAYMENT_TYPE_META: Record<string, PaymentTypeMeta> = {
   },
 };
 
-/** 获取支付方式的显示名称（如 '支付宝（易支付）'），用于管理后台等需要区分的场景 */
-export function getPaymentTypeLabel(type: string): string {
+const PAYMENT_TEXT_MAP: Record<Locale, Record<string, { label: string; provider: string; sublabel?: string }>> = {
+  zh: {
+    [PAYMENT_TYPE.ALIPAY]: { label: '支付宝', provider: '易支付' },
+    [PAYMENT_TYPE.ALIPAY_DIRECT]: { label: '支付宝', provider: '支付宝' },
+    [PAYMENT_TYPE.WXPAY]: { label: '微信支付', provider: '易支付' },
+    [PAYMENT_TYPE.WXPAY_DIRECT]: { label: '微信支付', provider: '微信支付' },
+    [PAYMENT_TYPE.STRIPE]: { label: 'Stripe', provider: 'Stripe' },
+  },
+  en: {
+    [PAYMENT_TYPE.ALIPAY]: { label: 'Alipay', provider: 'EasyPay' },
+    [PAYMENT_TYPE.ALIPAY_DIRECT]: { label: 'Alipay', provider: 'Alipay' },
+    [PAYMENT_TYPE.WXPAY]: { label: 'WeChat Pay', provider: 'EasyPay' },
+    [PAYMENT_TYPE.WXPAY_DIRECT]: { label: 'WeChat Pay', provider: 'WeChat Pay' },
+    [PAYMENT_TYPE.STRIPE]: { label: 'Stripe', provider: 'Stripe' },
+  },
+};
+
+function getPaymentText(type: string, locale: Locale = 'zh'): { label: string; provider: string; sublabel?: string } {
   const meta = PAYMENT_TYPE_META[type];
+  if (!meta) return { label: type, provider: '' };
+  const baseText = PAYMENT_TEXT_MAP[locale][type] || { label: meta.label, provider: meta.provider };
+  return {
+    ...baseText,
+    sublabel: meta.sublabel,
+  };
+}
+
+export function getPaymentTypeLabel(type: string, locale: Locale = 'zh'): string {
+  const meta = getPaymentText(type, locale);
   if (!meta) return type;
-  if (meta.sublabel) return `${meta.label}（${meta.sublabel}）`;
-  // 无 sublabel 时，检查是否有同名渠道需要用 provider 区分
-  const hasDuplicate = Object.entries(PAYMENT_TYPE_META).some(
-    ([k, m]) => k !== type && m.label === meta.label,
+  if (meta.sublabel) {
+    return locale === 'en' ? `${meta.label} (${meta.sublabel})` : `${meta.label}（${meta.sublabel}）`;
+  }
+  const hasDuplicate = Object.keys(PAYMENT_TYPE_META).some(
+    (key) => key !== type && getPaymentText(key, locale).label === meta.label,
   );
-  return hasDuplicate ? `${meta.label}（${meta.provider}）` : meta.label;
+  if (!hasDuplicate || !meta.provider) return meta.label;
+  return locale === 'en' ? `${meta.label} (${meta.provider})` : `${meta.label}（${meta.provider}）`;
 }
 
-/** 获取支付渠道和提供商的结构化信息 */
-export function getPaymentDisplayInfo(type: string): { channel: string; provider: string } {
-  const meta = PAYMENT_TYPE_META[type];
-  if (!meta) return { channel: type, provider: '' };
-  return { channel: meta.label, provider: meta.provider };
+export function getPaymentDisplayInfo(type: string, locale: Locale = 'zh'): { channel: string; provider: string; sublabel?: string } {
+  const meta = getPaymentText(type, locale);
+  return { channel: meta.label, provider: meta.provider, sublabel: meta.sublabel };
 }
 
-/** 获取基础支付方式图标类型（alipay_direct → alipay） */
 export function getPaymentIconType(type: string): string {
   if (type.startsWith(PAYMENT_PREFIX.ALIPAY)) return PAYMENT_PREFIX.ALIPAY;
   if (type.startsWith(PAYMENT_PREFIX.WXPAY)) return PAYMENT_PREFIX.WXPAY;
@@ -180,23 +223,19 @@ export function getPaymentIconType(type: string): string {
   return type;
 }
 
-/** 获取支付方式的元数据，带合理的 fallback */
 export function getPaymentMeta(type: string): PaymentTypeMeta {
   const base = getPaymentIconType(type);
   return PAYMENT_TYPE_META[type] || PAYMENT_TYPE_META[base] || PAYMENT_TYPE_META[PAYMENT_TYPE.ALIPAY];
 }
 
-/** 获取支付方式图标路径 */
 export function getPaymentIconSrc(type: string): string {
   return getPaymentMeta(type).iconSrc || '';
 }
 
-/** 获取支付方式简短标签（如 '支付宝'、'微信'、'Stripe'） */
-export function getPaymentChannelLabel(type: string): string {
-  return getPaymentMeta(type).label;
+export function getPaymentChannelLabel(type: string, locale: Locale = 'zh'): string {
+  return getPaymentDisplayInfo(type, locale).channel;
 }
 
-/** 支付类型谓词函数 */
 export function isStripeType(type: string | undefined | null): boolean {
   return !!type?.startsWith(PAYMENT_PREFIX.STRIPE);
 }
@@ -209,12 +248,10 @@ export function isAlipayType(type: string | undefined | null): boolean {
   return !!type?.startsWith(PAYMENT_PREFIX.ALIPAY);
 }
 
-/** 该支付方式需要页面跳转（而非二维码） */
 export function isRedirectPayment(type: string | undefined | null): boolean {
   return !!type && REDIRECT_PAYMENT_TYPES.has(type);
 }
 
-/** 用自定义 sublabel 覆盖默认值 */
 export function applySublabelOverrides(overrides: Record<string, string>): void {
   for (const [type, sublabel] of Object.entries(overrides)) {
     if (PAYMENT_TYPE_META[type]) {

src/lib/utils/api.ts

@@ -1,13 +1,31 @@
 import { NextRequest, NextResponse } from 'next/server';
 import { OrderError } from '@/lib/order/service';
+import { resolveLocale } from '@/lib/locale';
 
 /** 统一处理 OrderError 和未知错误 */
-export function handleApiError(error: unknown, fallbackMessage: string): NextResponse {
+export function handleApiError(error: unknown, fallbackMessage: string, request?: NextRequest): NextResponse {
   if (error instanceof OrderError) {
     return NextResponse.json({ error: error.message, code: error.code }, { status: error.statusCode });
   }
-  console.error(`${fallbackMessage}:`, error);
-  return NextResponse.json({ error: fallbackMessage }, { status: 500 });
+  const locale = resolveLocale(request?.nextUrl.searchParams.get('lang'));
+  const resolvedFallback = locale === 'en' ? translateFallbackMessage(fallbackMessage) : fallbackMessage;
+  console.error(`${resolvedFallback}:`, error);
+  return NextResponse.json({ error: resolvedFallback }, { status: 500 });
+}
+
+function translateFallbackMessage(message: string): string {
+  switch (message) {
+    case '退款失败':
+      return 'Refund failed';
+    case '重试充值失败':
+      return 'Recharge retry failed';
+    case '取消订单失败':
+      return 'Cancel order failed';
+    case '获取用户信息失败':
+      return 'Failed to fetch user info';
+    default:
+      return message;
+  }
 }
 
 /** 从 NextRequest 提取 headers 为普通对象 */