import { BadRequestException, Injectable } from '@nestjs/common';
import { PrismaService } from '../../common/prisma/prisma.module';
import { serializeBigInt } from '../../common/decorators/current-user.decorator';
import { groupResourcesByProductId, mapProductMedia } from './catalog.mapper';

@Injectable()
export class CatalogService {
  constructor(private readonly prisma: PrismaService) {}

  async listCities() {
    const cities = await this.prisma.commonCity.findMany({
      where: { status: 'ACTIVE' },
      include: { partner: { select: { companyName: true } } },
      orderBy: { name: 'asc' },
    });
    return serializeBigInt(cities);
  }

  async listProducts(aromaType?: string, cityCode?: string) {
    if (cityCode) {
      const city = await this.prisma.commonCity.findFirst({
        where: { code: cityCode, status: 'ACTIVE' },
      });
      if (!city) throw new BadRequestException('该城市暂未开城');
    }

    const products = await this.prisma.commonProductItem.findMany({
      where: { status: 'ON_SALE', ...(aromaType ? { aromaType: aromaType as never } : {}) },
      orderBy: { sortOrder: 'asc' },
      include: { coverResource: true },
    });

    const productIds = products.map((p) => p.id);
    const resources = productIds.length
      ? await this.prisma.commonResource.findMany({
          where: {
            ownerType: 'PRODUCT',
            ownerId: { in: productIds },
            status: 'ACTIVE',
            bizType: { in: ['CAROUSEL', 'DETAIL'] },
          },
          orderBy: { sortOrder: 'asc' },
        })
      : [];
    const resourceMap = groupResourcesByProductId(resources);

    return serializeBigInt(
      products.map((p) => {
        const media = mapProductMedia(p, resourceMap.get(p.id.toString()) ?? []);
        return {
          ...p,
          benefitAmount: p.benefitAmount ?? p.price,
          price: Number(p.price),
          benefitDisplay: Number(p.benefitAmount ?? p.price),
          ...media,
        };
      }),
    );
  }

  async getProduct(id: bigint) {
    const product = await this.prisma.commonProductItem.findUnique({
      where: { id },
      include: { coverResource: true },
    });
    if (!product) return null;

    const resources = await this.prisma.commonResource.findMany({
      where: {
        ownerType: 'PRODUCT',
        ownerId: id,
        status: 'ACTIVE',
        bizType: { in: ['CAROUSEL', 'DETAIL'] },
      },
      orderBy: { sortOrder: 'asc' },
    });

    const media = mapProductMedia(product, resources);
    return serializeBigInt({
      ...product,
      benefitAmount: product.benefitAmount ?? product.price,
      price: Number(product.price),
      ...media,
    });
  }
}