feat: internationalize API error responses by locale

Add shared error codes with zh/en/ms messages, coded app exceptions,
and locale-aware global filter. Frontends send X-Locale so error text
matches the active UI language.

Co-authored-by: Cursor <cursoragent@cursor.com>

apps/api/src/domains/betting/bets.service.ts

@@ -1,10 +1,11 @@
-import { Injectable, BadRequestException, ConflictException, NotFoundException } from '@nestjs/common';
+import { Injectable, ConflictException, BadRequestException } from '@nestjs/common';
 import { Prisma } from '@prisma/client';
 import { PrismaService } from '../../shared/prisma/prisma.service';
 import { WalletService } from '../ledger/wallet.service';
 import { BettingLimitsService } from './betting-limits.service';
 import { Decimal } from '@prisma/client/runtime/library';
 import { generateBetNo } from '../../shared/common/decorators';
+import { appBadRequest, appNotFound } from '../../shared/common/app-error';
 import {
   PARLAY_MIN_LEGS,
   PARLAY_MAX_LEGS,
@@ -54,20 +55,20 @@ export class BetsService {
       include: { market: { include: { match: true } } },
     });
 
-    if (!selection) throw new BadRequestException('Selection not found');
-    if (selection.status !== 'OPEN') throw new BadRequestException('Selection closed');
-    if (selection.market.status !== 'OPEN') throw new BadRequestException('Market closed');
+    if (!selection) throw appBadRequest('SELECTION_NOT_FOUND');
+    if (selection.status !== 'OPEN') throw appBadRequest('SELECTION_CLOSED');
+    if (selection.market.status !== 'OPEN') throw appBadRequest('MARKET_CLOSED');
     if (selection.market.match.status !== 'PUBLISHED') {
-      throw new BadRequestException('Match not available for betting');
+      throw appBadRequest('MATCH_NOT_BETTING');
     }
     if (!isSupportedSport(selection.market.match.sportType)) {
-      throw new BadRequestException('Only football betting is supported');
+      throw appBadRequest('FOOTBALL_ONLY');
     }
     if (!selection.market.match.isOutright && !isPreMatchKickoff(selection.market.match.startTime)) {
-      throw new BadRequestException('Pre-match betting only; match has started');
+      throw appBadRequest('PRE_MATCH_ONLY');
     }
     if (selection.oddsVersion !== oddsVersion) {
-      throw new BadRequestException('Odds changed, please confirm again');
+      throw appBadRequest('ODDS_CHANGED');
     }
 
     if (options?.forParlay) {
@@ -79,13 +80,13 @@ export class BetsService {
         isOutright: selection.market.match.isOutright,
       });
       if (!check.ok) {
-        const msg =
+        const code =
           check.reason === 'OUTRIGHT'
-            ? 'Outright cannot be in parlay'
+            ? 'PARLAY_OUTRIGHT_FORBIDDEN'
             : check.reason === 'QUARTER_LINE'
-              ? 'Quarter line markets cannot be in parlay'
-              : 'Market not allowed in parlay';
-        throw new BadRequestException(msg);
+              ? 'PARLAY_QUARTER_LINE_FORBIDDEN'
+              : 'PARLAY_MARKET_NOT_ALLOWED';
+        throw appBadRequest(code);
       }
     }
 
@@ -100,7 +101,7 @@ export class BetsService {
     stake: number,
     requestId: string,
   ) {
-    if (stake <= 0) throw new BadRequestException('Invalid stake');
+    if (stake <= 0) throw appBadRequest('INVALID_STAKE');
 
     const existing = await this.prisma.bet.findUnique({
       where: { userId_requestId: { userId, requestId } },
@@ -162,9 +163,9 @@ export class BetsService {
     stake: number,
     requestId: string,
   ) {
-    if (stake <= 0) throw new BadRequestException('Invalid stake');
+    if (stake <= 0) throw appBadRequest('INVALID_STAKE');
     if (legs.length < PARLAY_MIN_LEGS || legs.length > PARLAY_MAX_LEGS) {
-      throw new BadRequestException(`Parlay must have ${PARLAY_MIN_LEGS}-${PARLAY_MAX_LEGS} legs`);
+      throw appBadRequest('PARLAY_LEG_COUNT_INVALID', { min: PARLAY_MIN_LEGS, max: PARLAY_MAX_LEGS });
     }
 
     const existing = await this.prisma.bet.findUnique({
@@ -527,7 +528,7 @@ export class BetsService {
         selections: { orderBy: { sortOrder: 'asc' } },
       },
     });
-    if (!bet) throw new NotFoundException('注单不存在');
+    if (!bet) throw appNotFound('BET_NOT_FOUND');
 
     const matchIds = bet.selections
       .map((s) => s.matchId)

apps/api/src/domains/betting/betting-limits.service.ts

@@ -1,6 +1,7 @@
-import { Injectable, BadRequestException } from '@nestjs/common';
+import { Injectable } from '@nestjs/common';
 import { Decimal } from '@prisma/client/runtime/library';
 import { PrismaService } from '../../shared/prisma/prisma.service';
+import { appBadRequest } from '../../shared/common/app-error';
 
 export type BettingLimits = {
   minStake: number;
@@ -89,18 +90,18 @@ export class BettingLimitsService {
     const stake = params.stake;
 
     if (stake < limits.minStake) {
-      throw new BadRequestException(`Minimum stake is ${limits.minStake}`);
+      throw appBadRequest('MIN_STAKE', { minStake: limits.minStake });
     }
 
     const maxStake = params.betType === 'PARLAY' ? limits.maxStakeParlay : limits.maxStakeSingle;
     if (stake > maxStake) {
-      throw new BadRequestException(`Maximum stake is ${maxStake}`);
+      throw appBadRequest('MAX_STAKE', { maxStake });
     }
 
     const maxPayout =
       params.betType === 'PARLAY' ? limits.maxPayoutParlay : limits.maxPayoutSingle;
     if (params.potentialReturn.gt(maxPayout)) {
-      throw new BadRequestException(`Potential return exceeds limit of ${maxPayout}`);
+      throw appBadRequest('MAX_PAYOUT', { maxPayout });
     }
 
     if (limits.dailyStakeLimit > 0) {
@@ -119,7 +120,7 @@ export class BettingLimitsService {
       });
       const todayStake = new Decimal(agg._sum.stake ?? 0);
       if (todayStake.add(stake).gt(limits.dailyStakeLimit)) {
-        throw new BadRequestException(`Daily stake limit of ${limits.dailyStakeLimit} exceeded`);
+        throw appBadRequest('DAILY_STAKE_LIMIT', { limit: limits.dailyStakeLimit });
       }
     }
   }