init

server/dukang-api/src/modules/benefit/benefit.service.ts

@@ -0,0 +1,92 @@
+import { Injectable } from '@nestjs/common';
+import { calcBenefitAmount, calcBenefitSummary, generateCouponNo } from '@dukang/domain';
+import { REDEEM_MAX_AMOUNT } from '@dukang/shared-types';
+import { PrismaService } from '../../common/prisma/prisma.module';
+import { serializeBigInt } from '../../common/decorators/current-user.decorator';
+
+@Injectable()
+export class BenefitService {
+  constructor(private readonly prisma: PrismaService) {}
+
+  async grantOnOrderPaid(orderId: bigint) {
+    const order = await this.prisma.order.findUniqueOrThrow({
+      where: { id: orderId },
+      include: { items: true },
+    });
+    const item = order.items[0];
+    if (!item) return null;
+
+    const product = await this.prisma.product.findUnique({ where: { id: item.productId } });
+    const unitBenefit = calcBenefitAmount({
+      price: Number(item.unitPrice),
+      benefitAmount: product?.benefitAmount ? Number(product.benefitAmount) : null,
+    });
+    const totalBenefit = unitBenefit * item.quantity;
+
+    const coupon = await this.prisma.benefitCoupon.create({
+      data: {
+        couponNo: generateCouponNo(),
+        userId: order.userId,
+        orderId: order.id,
+        totalAmount: totalBenefit,
+        balance: totalBenefit,
+        sourceProduct: item.productName,
+      },
+    });
+
+    await this.prisma.benefitLedger.create({
+      data: {
+        userId: order.userId,
+        couponId: coupon.id,
+        type: 'GRANT',
+        amount: totalBenefit,
+        balanceAfter: totalBenefit,
+        refType: 'ORDER',
+        refId: order.id,
+        remark: '购酒赠券',
+      },
+    });
+
+    return serializeBigInt(coupon);
+  }
+
+  async listCoupons(userId: bigint) {
+    const list = await this.prisma.benefitCoupon.findMany({
+      where: { userId, status: { in: ['ACTIVE', 'USED_UP'] } },
+      orderBy: { createdAt: 'desc' },
+    });
+    return serializeBigInt(list);
+  }
+
+  async getSummary(userId: bigint) {
+    const coupons = await this.prisma.benefitCoupon.findMany({
+      where: { userId, status: 'ACTIVE' },
+      orderBy: { createdAt: 'asc' },
+    });
+    const summary = calcBenefitSummary(
+      coupons.map((c) => Number(c.balance)),
+      REDEEM_MAX_AMOUNT,
+    );
+    return serializeBigInt(summary);
+  }
+
+  async getLedger(userId: bigint, couponId?: bigint) {
+    const list = await this.prisma.benefitLedger.findMany({
+      where: { userId, ...(couponId ? { couponId } : {}) },
+      orderBy: { createdAt: 'desc' },
+    });
+    return serializeBigInt(list);
+  }
+
+  async getCoupon(userId: bigint, couponId: bigint) {
+    const coupon = await this.prisma.benefitCoupon.findFirst({
+      where: { id: couponId, userId },
+    });
+    if (!coupon) return null;
+    const ledgers = await this.prisma.benefitLedger.findMany({
+      where: { couponId },
+      orderBy: { createdAt: 'desc' },
+    });
+    return serializeBigInt({ coupon, ledgers });
+  }
+}