feat: 插件化支付渠道限额 — provider 自声明单笔/每日默认限额

- PaymentProvider 接口新增 defaultLimits（单笔 singleMax + 每日 dailyMax）
- EasyPay 默认：支付宝/微信各 单笔 ¥1000、每日 ¥10000
- Stripe 默认：不限额（0 = unlimited）
- getMethodDailyLimit / getMethodSingleLimit 优先读 env var，再回退 provider 默认
- queryMethodLimits 返回 singleMax，PaymentForm 按渠道动态调整最大单笔金额
- MAX_DAILY_AMOUNT_* 改为可选 env var 覆盖（不再有硬编码默认值）

src/components/PaymentForm.tsx

@@ -6,6 +6,8 @@ import { PAYMENT_TYPE_META } from '@/lib/pay-utils';
 export interface MethodLimitInfo {
   available: boolean;
   remaining: number | null;
+  /** 单笔限额，0 = 使用全局 maxAmount */
+  singleMax?: number;
 }
 
 interface PaymentFormProps {
@@ -71,7 +73,9 @@ export default function PaymentForm({
 
   const selectedAmount = amount || 0;
   const isMethodAvailable = !methodLimits || (methodLimits[paymentType]?.available !== false);
-  const isValid = selectedAmount >= minAmount && selectedAmount <= maxAmount && hasValidCentPrecision(selectedAmount) && isMethodAvailable;
+  const methodSingleMax = methodLimits?.[paymentType]?.singleMax;
+  const effectiveMax = (methodSingleMax !== undefined && methodSingleMax > 0) ? methodSingleMax : maxAmount;
+  const isValid = selectedAmount >= minAmount && selectedAmount <= effectiveMax && hasValidCentPrecision(selectedAmount) && isMethodAvailable;
 
   const handleSubmit = async (e: React.FormEvent) => {
     e.preventDefault();
@@ -151,7 +155,7 @@ export default function PaymentForm({
           充值金额
         </label>
         <div className="grid grid-cols-3 gap-2">
-          {QUICK_AMOUNTS.filter((val) => val <= maxAmount).map((val) => (
+          {QUICK_AMOUNTS.filter((val) => val <= effectiveMax).map((val) => (
             <button
               key={val}
               type="button"
@@ -188,10 +192,10 @@ export default function PaymentForm({
             inputMode="decimal"
             step="0.01"
             min={minAmount}
-            max={maxAmount}
+            max={effectiveMax}
             value={customAmount}
             onChange={(e) => handleCustomAmountChange(e.target.value)}
-            placeholder={`${minAmount} - ${maxAmount}`}
+            placeholder={`${minAmount} - ${effectiveMax}`}
             className={[
               'w-full rounded-lg border py-3 pl-8 pr-4 focus:border-blue-500 focus:outline-none focus:ring-1 focus:ring-blue-500',
               dark ? 'border-slate-700 bg-slate-900 text-slate-100' : 'border-gray-300 bg-white text-gray-900',
@@ -205,7 +209,7 @@ export default function PaymentForm({
         let msg = '金额需在范围内，且最多支持 2 位小数（精确到分）';
         if (!isNaN(num)) {
           if (num < minAmount) msg = `单笔最低充值 ¥${minAmount}`;
-          else if (num > maxAmount) msg = `单笔最高充值 ¥${maxAmount}`;
+          else if (num > effectiveMax) msg = `单笔最高充值 ¥${effectiveMax}`;
         }
         return (
           <div className={['text-xs', dark ? 'text-amber-300' : 'text-amber-700'].join(' ')}>

src/lib/config.ts

@@ -37,11 +37,11 @@ const envSchema = z.object({
   // 每日每用户最大累计充值额，0 = 不限制
   MAX_DAILY_RECHARGE_AMOUNT: z.string().default('10000').transform(Number).pipe(z.number().min(0)),
 
-  // 每日各渠道全平台总限额，0 = 不限制
+  // 每日各渠道全平台总限额，可选覆盖（0 = 不限制）。
-  // 新增渠道按 MAX_DAILY_AMOUNT_{TYPE大写} 命名即可自动生效
+  // 未设置时由各 PaymentProvider.defaultLimits 提供默认值。
-  MAX_DAILY_AMOUNT_ALIPAY: z.string().default('10000').transform(Number).pipe(z.number().min(0)),
+  MAX_DAILY_AMOUNT_ALIPAY: z.string().optional().transform((v) => (v !== undefined ? Number(v) : undefined)).pipe(z.number().min(0).optional()),
-  MAX_DAILY_AMOUNT_WXPAY: z.string().default('10000').transform(Number).pipe(z.number().min(0)),
+  MAX_DAILY_AMOUNT_WXPAY: z.string().optional().transform((v) => (v !== undefined ? Number(v) : undefined)).pipe(z.number().min(0).optional()),
-  MAX_DAILY_AMOUNT_STRIPE: z.string().default('0').transform(Number).pipe(z.number().min(0)),
+  MAX_DAILY_AMOUNT_STRIPE: z.string().optional().transform((v) => (v !== undefined ? Number(v) : undefined)).pipe(z.number().min(0).optional()),
   PRODUCT_NAME: z.string().default('Sub2API Balance Recharge'),
 
   ADMIN_TOKEN: z.string().min(1),

src/lib/easy-pay/provider.ts

@@ -15,6 +15,10 @@ import { getEnv } from '@/lib/config';
 export class EasyPayProvider implements PaymentProvider {
   readonly name = 'easy-pay';
   readonly supportedTypes: PaymentType[] = ['alipay', 'wxpay'];
+  readonly defaultLimits = {
+    alipay: { singleMax: 1000, dailyMax: 10000 },
+    wxpay:  { singleMax: 1000, dailyMax: 10000 },
+  };
 
   async createPayment(request: CreatePaymentRequest): Promise<CreatePaymentResponse> {
     const result = await createPayment({

src/lib/order/limits.ts

@@ -1,17 +1,23 @@
 import { prisma } from '@/lib/db';
 import { getEnv } from '@/lib/config';
+import { initPaymentProviders, paymentRegistry } from '@/lib/payment';
 
 /**
  * 获取指定支付渠道的每日全平台限额（0 = 不限制）。
- * 优先读 config（Zod 验证），兜底读 process.env，适配未来动态注册的新渠道。
+ * 优先级：环境变量显式配置 > provider 默认值 > process.env 兜底 > 0
  */
 export function getMethodDailyLimit(paymentType: string): number {
   const env = getEnv();
   const key = `MAX_DAILY_AMOUNT_${paymentType.toUpperCase()}` as keyof typeof env;
   const val = env[key];
-  if (typeof val === 'number') return val;
+  if (typeof val === 'number') return val; // 明确配置（含 0）
 
-  // 兜底：支持动态渠道（未在 schema 中声明的 MAX_DAILY_AMOUNT_* 变量）
+  // 尝试从已注册的 provider 取默认值
+  initPaymentProviders();
+  const providerDefault = paymentRegistry.getDefaultLimit(paymentType);
+  if (providerDefault?.dailyMax !== undefined) return providerDefault.dailyMax;
+
+  // 兜底：process.env（支持未在 schema 中声明的动态渠道）
   const raw = process.env[`MAX_DAILY_AMOUNT_${paymentType.toUpperCase()}`];
   if (raw !== undefined) {
     const num = Number(raw);
@@ -20,15 +26,35 @@ export function getMethodDailyLimit(paymentType: string): number {
   return 0; // 默认不限制
 }
 
+/**
+ * 获取指定支付渠道的单笔限额（0 = 使用全局 MAX_RECHARGE_AMOUNT）。
+ * 优先级：process.env MAX_SINGLE_AMOUNT_* > provider 默认值 > 0
+ */
+export function getMethodSingleLimit(paymentType: string): number {
+  const raw = process.env[`MAX_SINGLE_AMOUNT_${paymentType.toUpperCase()}`];
+  if (raw !== undefined) {
+    const num = Number(raw);
+    if (Number.isFinite(num) && num >= 0) return num;
+  }
+
+  initPaymentProviders();
+  const providerDefault = paymentRegistry.getDefaultLimit(paymentType);
+  if (providerDefault?.singleMax !== undefined) return providerDefault.singleMax;
+
+  return 0; // 使用全局 MAX_RECHARGE_AMOUNT
+}
+
 export interface MethodLimitStatus {
   /** 每日限额，0 = 不限 */
   dailyLimit: number;
   /** 今日已使用金额 */
   used: number;
-  /** 剩余额度，null = 不限 */
+  /** 剩余每日额度，null = 不限 */
   remaining: number | null;
   /** 是否还可使用（false = 今日额度已满） */
   available: boolean;
+  /** 单笔限额，0 = 使用全局配置 MAX_RECHARGE_AMOUNT */
+  singleMax: number;
 }
 
 /**
@@ -58,6 +84,7 @@ export async function queryMethodLimits(
   const result: Record<string, MethodLimitStatus> = {};
   for (const type of paymentTypes) {
     const dailyLimit = getMethodDailyLimit(type);
+    const singleMax = getMethodSingleLimit(type);
     const used = usageMap[type] ?? 0;
     const remaining = dailyLimit > 0 ? Math.max(0, dailyLimit - used) : null;
     result[type] = {
@@ -65,6 +92,7 @@ export async function queryMethodLimits(
       used,
       remaining,
       available: dailyLimit === 0 || used < dailyLimit,
+      singleMax,
     };
   }
   return result;

src/lib/payment/registry.ts

@@ -1,4 +1,4 @@
-import type { PaymentProvider, PaymentType } from './types';
+import type { PaymentProvider, PaymentType, MethodDefaultLimits } from './types';
 
 export class PaymentProviderRegistry {
   private providers = new Map<PaymentType, PaymentProvider>();
@@ -24,6 +24,12 @@ export class PaymentProviderRegistry {
   getSupportedTypes(): PaymentType[] {
     return Array.from(this.providers.keys());
   }
+
+  /** 获取指定渠道的提供商默认限额（未注册时返回 undefined） */
+  getDefaultLimit(type: string): MethodDefaultLimits | undefined {
+    const provider = this.providers.get(type as PaymentType);
+    return provider?.defaultLimits?.[type];
+  }
 }
 
 export const paymentRegistry = new PaymentProviderRegistry();

src/lib/payment/types.ts

@@ -51,10 +51,20 @@ export interface RefundResponse {
   status: 'success' | 'pending' | 'failed';
 }
 
+/** Per-method default limits declared by the provider */
+export interface MethodDefaultLimits {
+  /** 单笔最大金额，0 = 不限（使用全局 MAX_RECHARGE_AMOUNT） */
+  singleMax?: number;
+  /** 每日全平台最大金额，0 = 不限 */
+  dailyMax?: number;
+}
+
 /** Common interface that all payment providers must implement */
 export interface PaymentProvider {
   readonly name: string;
   readonly supportedTypes: PaymentType[];
+  /** 各渠道默认限额，key 为 PaymentType（如 'alipay'），可被环境变量覆盖 */
+  readonly defaultLimits?: Record<string, MethodDefaultLimits>;
 
   createPayment(request: CreatePaymentRequest): Promise<CreatePaymentResponse>;
   queryOrder(tradeNo: string): Promise<QueryOrderResponse>;

src/lib/stripe/provider.ts

@@ -15,6 +15,9 @@ import type {
 export class StripeProvider implements PaymentProvider {
   readonly name = 'stripe';
   readonly supportedTypes: PaymentType[] = ['stripe'];
+  readonly defaultLimits = {
+    stripe: { singleMax: 0, dailyMax: 0 }, // 0 = unlimited
+  };
 
   private client: Stripe | null = null;