import {
  BadRequestException,
  ForbiddenException,
  Injectable,
  NotFoundException,
} from '@nestjs/common';
import {
  CityLevel,
  ContentStatus,
  MediaEntityType,
  Prisma,
  TechnicalFieldType,
} from '@prisma/client';
import { AuthUser } from '../auth/auth.types';
import { PermissionsService } from '../auth/permissions.service';
import { CategoryTechnicalFormService } from '../categories/category-technical-form.service';
import {
  applySeoMetaToMetadata,
  normalizeSeoMetaInput,
  readSeoMetaFromMetadata,
} from '../common/seo-meta.util';
import { MediaService } from '../media/media.service';
import { PrismaService } from '../prisma/prisma.service';
import {
  CreateUserProductDto,
  ListAdminUserProductsDto,
  ListMyUserProductsDto,
  ListPublicUserProductsDto,
  UpdateUserProductDto,
  UpdateUserProductStatusDto,
  UserProductTechnicalValueDto,
} from './dto/user-product.dto';
import { TenantService } from '../tenant/tenant.service';
import { SitemapService } from '../sitemap/sitemap.service';
import { slugifyForUrl } from '../sitemap/seo-slug.util';

function buildUserProductSlug(titleFa: string, titleEn?: string | null): string {
  return slugifyForUrl(
    titleFa.trim() || titleEn?.trim() || '',
    'user-product',
  );
}

type FormField = {
  id: string;
  label: string;
  key: string;
  type: TechnicalFieldType;
  isRequired: boolean;
  sortOrder: number;
  options: { id: string; label: string; value: string; sortOrder: number }[];
};

const userProductListInclude = {
  featuredMedia: true,
  city: true,
  country: true,
} satisfies Prisma.UserProductInclude;

type UserProductListRow = Prisma.UserProductGetPayload<{
  include: typeof userProductListInclude;
}>;

const userProductAdminListInclude = {
  ...userProductListInclude,
  user: {
    select: {
      id: true,
      firstName: true,
      lastName: true,
      firstNameEn: true,
      lastNameEn: true,
      cellNumber: true,
    },
  },
} satisfies Prisma.UserProductInclude;

type UserProductAdminListRow = Prisma.UserProductGetPayload<{
  include: typeof userProductAdminListInclude;
}>;

const userProductDetailInclude = {
  ...userProductListInclude,
  technicalFieldValues: {
    include: {
      selectedOptions: true,
    },
  },
} satisfies Prisma.UserProductInclude;

type UserProductDetailRow = Prisma.UserProductGetPayload<{
  include: typeof userProductDetailInclude;
}>;

const userProductAdminDetailInclude = {
  ...userProductAdminListInclude,
  technicalFieldValues: {
    include: {
      selectedOptions: true,
    },
  },
} satisfies Prisma.UserProductInclude;

type UserProductAdminDetailRow = Prisma.UserProductGetPayload<{
  include: typeof userProductAdminDetailInclude;
}>;

@Injectable()
export class UserProductsService {
  constructor(
    private readonly prisma: PrismaService,
    private readonly permissions: PermissionsService,
    private readonly technicalFormService: CategoryTechnicalFormService,
    private readonly mediaService: MediaService,
    private readonly tenant: TenantService,
    private readonly sitemap: SitemapService,
  ) {}

  async listPublic(host: string, query: ListPublicUserProductsDto) {
    const business = await this.tenant.resolveBusinessByDomain(host);
    const businessId = business.id;

    const page = query.page ?? 1;
    const pageSize = Math.min(Math.max(query.pageSize ?? 12, 1), 100);
    const skip = (page - 1) * pageSize;
    const where = await this.buildPublicWhere(businessId, query);

    const [items, total] = await Promise.all([
      this.prisma.userProduct.findMany({
        where,
        orderBy: [
          { publishedAt: 'desc' },
          { createdAt: 'desc' },
        ],
        skip,
        take: pageSize,
        include: userProductListInclude,
      }),
      this.prisma.userProduct.count({ where }),
    ]);

    const categoryByEntity = await this.loadCategoriesForProducts(
      businessId,
      items.map((item) => item.id),
    );

    const serialized = items.map((item) =>
      this.serializeListItem(item, categoryByEntity.get(item.id.toString())),
    );

    const promotedOnly = query.promoted === true;
    const ordered = promotedOnly
      ? serialized
      : [
          ...serialized.filter((item) => item.promoted),
          ...serialized.filter((item) => !item.promoted),
        ];

    return {
      items: ordered,
      total,
      page,
      pageSize,
    };
  }

  async getPublicBySlug(host: string, slug: string) {
    const business = await this.tenant.resolveBusinessByDomain(host);
    const product = await this.prisma.userProduct.findFirst({
      where: {
        businessId: business.id,
        slug,
        status: ContentStatus.published,
      },
      include: userProductDetailInclude,
    });

    if (!product) {
      throw new NotFoundException('User product not found');
    }

    return this.serializePublicDetail(business.id, product);
  }

  async getPublicById(host: string, productIdRaw: string) {
    const business = await this.tenant.resolveBusinessByDomain(host);
    let productId: bigint;
    try {
      productId = BigInt(productIdRaw);
    } catch {
      throw new NotFoundException('User product not found');
    }

    const product = await this.prisma.userProduct.findFirst({
      where: {
        businessId: business.id,
        id: productId,
        status: ContentStatus.published,
      },
      include: userProductDetailInclude,
    });

    if (!product) {
      throw new NotFoundException('User product not found');
    }

    return this.serializePublicDetail(business.id, product);
  }

  async getPublicTechnicalInfoBySlug(host: string, slug: string) {
    const business = await this.tenant.resolveBusinessByDomain(host);
    const product = await this.prisma.userProduct.findFirst({
      where: {
        businessId: business.id,
        slug,
        status: ContentStatus.published,
      },
      select: { id: true },
    });

    if (!product) {
      throw new NotFoundException('User product not found');
    }

    return this.getPublicTechnicalInfoForProduct(business.id, product.id);
  }

  async getPublicTechnicalInfoById(host: string, productIdRaw: string) {
    const business = await this.tenant.resolveBusinessByDomain(host);
    let productId: bigint;
    try {
      productId = BigInt(productIdRaw);
    } catch {
      throw new NotFoundException('User product not found');
    }

    const product = await this.prisma.userProduct.findFirst({
      where: {
        businessId: business.id,
        id: productId,
        status: ContentStatus.published,
      },
      select: { id: true },
    });

    if (!product) {
      throw new NotFoundException('User product not found');
    }

    return this.getPublicTechnicalInfoForProduct(business.id, product.id);
  }

  private async serializePublicDetail(
    businessId: bigint,
    product: UserProductDetailRow,
  ) {
    const categoryByEntity = await this.loadCategoriesForProducts(businessId, [
      product.id,
    ]);
    const gallery = await this.loadGalleryAttachments(businessId, product.id);

    return {
      product: this.serializeDetail(
        product,
        categoryByEntity.get(product.id.toString()),
        gallery,
      ),
    };
  }

  private async getPublicTechnicalInfoForProduct(
    businessId: bigint,
    productId: bigint,
  ) {
    const categoryByEntity = await this.loadCategoriesForProducts(businessId, [
      productId,
    ]);
    const category = categoryByEntity.get(productId.toString());
    if (!category) {
      return {
        form: null,
        values: [],
        message: 'User product has no category assigned',
      };
    }

    const form = await this.technicalFormService.getFormForCategory(
      businessId,
      category.id,
    );
    if (!form) {
      return { form: null, values: [] };
    }

    const detail = await this.prisma.userProduct.findFirst({
      where: { id: productId },
      include: userProductDetailInclude,
    });
    if (!detail) {
      throw new NotFoundException('User product not found');
    }

    const serialized = this.serializeDetail(detail, category, []);
    return {
      form,
      values: serialized.technicalValues,
    };
  }

  async list(
    businessIdRaw: string,
    query: ListMyUserProductsDto,
    actor: AuthUser,
  ) {
    const businessId = BigInt(businessIdRaw);
    await this.assertCustomerAccess(businessId, actor);

    const page = query.page ?? 1;
    const pageSize = Math.min(Math.max(query.pageSize ?? 20, 1), 100);
    const skip = (page - 1) * pageSize;

    const where: Prisma.UserProductWhereInput = {
      businessId,
      userId: actor.id,
    };

    const [items, total] = await Promise.all([
      this.prisma.userProduct.findMany({
        where,
        orderBy: { createdAt: 'desc' },
        skip,
        take: pageSize,
        include: userProductListInclude,
      }),
      this.prisma.userProduct.count({ where }),
    ]);

    const categoryByEntity = await this.loadCategoriesForProducts(
      businessId,
      items.map((item) => item.id),
    );

    return {
      items: items.map((item) =>
        this.serializeListItem(item, categoryByEntity.get(item.id.toString())),
      ),
      total,
      page,
      pageSize,
    };
  }

  async create(
    businessIdRaw: string,
    dto: CreateUserProductDto,
    actor: AuthUser,
  ) {
    const businessId = BigInt(businessIdRaw);
    await this.assertCustomerAccess(businessId, actor);
    return this.createForUser(businessId, dto, actor.id);
  }

  private async createForUser(
    businessId: bigint,
    dto: CreateUserProductDto,
    userId: bigint,
  ) {
    const titleFa = dto.titleFa.trim();
    if (!titleFa) {
      throw new BadRequestException('titleFa is required');
    }

    const categoryId = BigInt(dto.categoryId);
    await this.assertProductCategory(businessId, categoryId);

    const countryId = BigInt(dto.countryId);
    const cityId = BigInt(dto.cityId);
    await this.assertCountryAndCity(countryId, cityId);

    let featuredMediaId: bigint | null = null;
    if (dto.featuredMediaId) {
      featuredMediaId = BigInt(dto.featuredMediaId);
      await this.assertMediaBelongsToBusiness(businessId, featuredMediaId);
    }

    const galleryMediaIds = await this.resolveGalleryMediaIds(
      businessId,
      dto.galleryMediaIds ?? [],
    );

    const form = await this.technicalFormService.getFormForCategory(
      businessId,
      categoryId,
    );
    const technicalValues = dto.technicalValues ?? [];
    this.validateTechnicalValues(form?.fields ?? [], technicalValues);

    const slug = await this.ensureUniqueSlug(
      businessId,
      buildUserProductSlug(titleFa, dto.titleEn),
    );
    const priceCurrency = dto.priceCurrency ?? 'IRT';
    const content: Prisma.InputJsonValue = {
      ...(dto.titleEn?.trim() ? { titleEn: dto.titleEn.trim() } : {}),
    };
    const metadata = applySeoMetaToMetadata(
      {
        priceByExpert: dto.priceByExpert === true,
      },
      normalizeSeoMetaInput(dto.seoMetaTitle, dto.seoMetaDescription),
    ) as Prisma.InputJsonValue;

    const created = await this.prisma.$transaction(async (tx) => {
      const product = await tx.userProduct.create({
        data: {
          businessId,
          userId,
          title: titleFa,
          slug,
          description: dto.description?.trim() || null,
          content,
          price:
            dto.price === undefined || dto.price === null
              ? null
              : dto.price,
          priceCurrency,
          status: ContentStatus.draft,
          featuredMediaId,
          countryId,
          cityId,
          deliveryNote: dto.deliveryNote?.trim() || null,
          condition: dto.condition,
          technicalNotes: dto.technicalNotes?.trim() || null,
          metadata,
        },
        include: userProductListInclude,
      });

      await tx.categoryAssignment.create({
        data: {
          businessId,
          categoryId,
          entityType: MediaEntityType.user_product,
          entityId: product.id,
        },
      });

      await this.syncGalleryAttachments(
        tx,
        businessId,
        product.id,
        galleryMediaIds,
      );

      if (form?.fields.length) {
        await this.saveTechnicalValues(
          tx,
          businessId,
          product.id,
          form.fields,
          technicalValues,
        );
      }

      return product;
    });

    const category = await this.prisma.category.findFirst({
      where: { id: categoryId, businessId },
      select: { id: true, name: true, nameFa: true },
    });

    const withUser = await this.prisma.userProduct.findFirst({
      where: { id: created.id },
      include: userProductAdminListInclude,
    });

    await this.sitemap.invalidateForBusiness(businessId);

    return {
      message: 'User product created successfully',
      product: withUser
        ? this.serializeAdminListItem(withUser, category ?? undefined)
        : this.serializeListItem(created, category ?? undefined),
    };
  }

  async getOne(
    businessIdRaw: string,
    productIdRaw: string,
    actor: AuthUser,
  ) {
    const businessId = BigInt(businessIdRaw);
    const productId = BigInt(productIdRaw);
    await this.assertCustomerAccess(businessId, actor);

    const product = await this.prisma.userProduct.findFirst({
      where: { id: productId, businessId, userId: actor.id },
      include: userProductDetailInclude,
    });

    if (!product) {
      throw new NotFoundException('User product not found');
    }

    const categoryByEntity = await this.loadCategoriesForProducts(businessId, [
      product.id,
    ]);
    const gallery = await this.loadGalleryAttachments(businessId, product.id);

    return {
      product: this.serializeDetail(
        product,
        categoryByEntity.get(product.id.toString()),
        gallery,
      ),
    };
  }

  async update(
    businessIdRaw: string,
    productIdRaw: string,
    dto: UpdateUserProductDto,
    actor: AuthUser,
  ) {
    const businessId = BigInt(businessIdRaw);
    const productId = BigInt(productIdRaw);
    await this.assertCustomerAccess(businessId, actor);

    const existing = await this.prisma.userProduct.findFirst({
      where: { id: productId, businessId, userId: actor.id },
      select: {
        id: true,
        title: true,
        slug: true,
        metadata: true,
        featuredMediaId: true,
      },
    });

    if (!existing) {
      throw new NotFoundException('User product not found');
    }

    return this.updateExisting(businessId, productId, dto, existing);
  }

  private async updateExisting(
    businessId: bigint,
    productId: bigint,
    dto: UpdateUserProductDto,
    existing: {
      id: bigint;
      title: string;
      slug: string;
      metadata: unknown;
      featuredMediaId: bigint | null;
    },
  ) {
    const titleFa = dto.titleFa.trim();
    if (!titleFa) {
      throw new BadRequestException('titleFa is required');
    }

    const categoryId = BigInt(dto.categoryId);
    await this.assertProductCategory(businessId, categoryId);

    const countryId = BigInt(dto.countryId);
    const cityId = BigInt(dto.cityId);
    await this.assertCountryAndCity(countryId, cityId);

    let featuredMediaId: bigint | null = null;
    if (dto.featuredMediaId) {
      featuredMediaId = BigInt(dto.featuredMediaId);
      await this.assertMediaBelongsToBusiness(businessId, featuredMediaId);
    }

    const galleryMediaIds =
      dto.galleryMediaIds !== undefined
        ? await this.resolveGalleryMediaIds(businessId, dto.galleryMediaIds)
        : null;

    const form = await this.technicalFormService.getFormForCategory(
      businessId,
      categoryId,
    );
    const technicalValues = dto.technicalValues ?? [];
    this.validateTechnicalValues(form?.fields ?? [], technicalValues);

    const existingMetadata = this.asRecord(existing.metadata);
    const content: Prisma.InputJsonValue = {
      ...(dto.titleEn?.trim() ? { titleEn: dto.titleEn.trim() } : {}),
    };
    const metadata = applySeoMetaToMetadata(
      {
        ...existingMetadata,
        priceByExpert: dto.priceByExpert === true,
      },
      normalizeSeoMetaInput(dto.seoMetaTitle, dto.seoMetaDescription),
    ) as Prisma.InputJsonValue;

    let slug = existing.slug;
    if (titleFa !== existing.title) {
      slug = await this.ensureUniqueSlug(
        businessId,
        buildUserProductSlug(titleFa, dto.titleEn),
        productId,
      );
    }

    const previousGalleryIds = await this.mediaService.galleryMediaIds(
      businessId,
      MediaEntityType.user_product,
      productId,
    );

    const updated = await this.prisma.$transaction(async (tx) => {
      const product = await tx.userProduct.update({
        where: { id: productId },
        data: {
          title: titleFa,
          slug,
          description: dto.description?.trim() || null,
          content,
          price:
            dto.price === undefined || dto.price === null ? null : dto.price,
          priceCurrency: dto.priceCurrency ?? 'IRT',
          featuredMediaId,
          countryId,
          cityId,
          deliveryNote: dto.deliveryNote?.trim() || null,
          condition: dto.condition,
          technicalNotes: dto.technicalNotes?.trim() || null,
          metadata,
        },
        include: userProductAdminListInclude,
      });

      await tx.categoryAssignment.deleteMany({
        where: {
          businessId,
          entityType: MediaEntityType.user_product,
          entityId: productId,
        },
      });
      await tx.categoryAssignment.create({
        data: {
          businessId,
          categoryId,
          entityType: MediaEntityType.user_product,
          entityId: productId,
        },
      });

      if (galleryMediaIds !== null) {
        await this.syncGalleryAttachments(
          tx,
          businessId,
          productId,
          galleryMediaIds,
        );
      }

      await tx.userProductTechnicalFieldValue.deleteMany({
        where: { userProductId: productId },
      });

      if (form?.fields.length) {
        await this.saveTechnicalValues(
          tx,
          businessId,
          productId,
          form.fields,
          technicalValues,
        );
      }

      return product;
    });

    const category = await this.prisma.category.findFirst({
      where: { id: categoryId, businessId },
      select: { id: true, name: true, nameFa: true },
    });

    const dropped: bigint[] = [];
    if (galleryMediaIds !== null) {
      dropped.push(
        ...this.mediaService.idsNotIn(previousGalleryIds, galleryMediaIds),
      );
    }
    if (
      existing.featuredMediaId != null &&
      existing.featuredMediaId !== featuredMediaId
    ) {
      dropped.push(existing.featuredMediaId);
    }
    await this.mediaService.deleteUnused(businessId, dropped);

    await this.sitemap.invalidateForBusiness(businessId);

    return {
      message: 'User product updated successfully',
      product: this.serializeAdminListItem(updated, category ?? undefined),
    };
  }

  async uploadMedia(
    businessIdRaw: string,
    files: Express.Multer.File[],
    actor: AuthUser,
  ) {
    return this.mediaService.uploadManyForCustomer(businessIdRaw, files, actor);
  }

  async remove(
    businessIdRaw: string,
    productIdRaw: string,
    actor: AuthUser,
  ) {
    const businessId = BigInt(businessIdRaw);
    const productId = BigInt(productIdRaw);
    await this.assertCustomerAccess(businessId, actor);

    const product = await this.prisma.userProduct.findFirst({
      where: { id: productId, businessId, userId: actor.id },
      select: { id: true, featuredMediaId: true },
    });

    if (!product) {
      throw new NotFoundException('User product not found');
    }

    const mediaIds = await this.mediaService.allLinkedMediaIds(
      businessId,
      MediaEntityType.user_product,
      productId,
      product.featuredMediaId,
    );

    await this.prisma.$transaction(async (tx) => {
      await tx.mediaAttachment.deleteMany({
        where: {
          businessId,
          entityType: MediaEntityType.user_product,
          entityId: productId,
        },
      });
      await tx.categoryAssignment.deleteMany({
        where: {
          businessId,
          entityType: MediaEntityType.user_product,
          entityId: productId,
        },
      });
      await tx.userProduct.delete({ where: { id: productId } });
    });

    await this.mediaService.deleteUnused(businessId, mediaIds);

    await this.sitemap.invalidateForBusiness(businessId);

    return { message: 'User product deleted successfully' };
  }

  async promote(
    businessIdRaw: string,
    productIdRaw: string,
    actor: AuthUser,
  ) {
    const businessId = BigInt(businessIdRaw);
    const productId = BigInt(productIdRaw);
    await this.assertCustomerAccess(businessId, actor);

    const product = await this.prisma.userProduct.findFirst({
      where: { id: productId, businessId, userId: actor.id },
      include: userProductListInclude,
    });

    if (!product) {
      throw new NotFoundException('User product not found');
    }

    const metadata = this.asRecord(product.metadata);
    const nextMetadata: Prisma.InputJsonValue = {
      ...metadata,
      promoted: true,
      promotedAt: new Date().toISOString(),
    };

    const updated = await this.prisma.userProduct.update({
      where: { id: productId },
      data: { metadata: nextMetadata },
      include: userProductListInclude,
    });

    const categoryByEntity = await this.loadCategoriesForProducts(businessId, [
      updated.id,
    ]);

    return {
      message: 'User product promoted successfully',
      product: this.serializeListItem(
        updated,
        categoryByEntity.get(updated.id.toString()),
      ),
    };
  }

  async adminList(
    businessIdRaw: string,
    query: ListAdminUserProductsDto,
    actor: AuthUser,
  ) {
    const businessId = BigInt(businessIdRaw);
    await this.assertAdminAccess(businessId, actor, 'user_products.read');

    const page = query.page ?? 1;
    const pageSize = Math.min(Math.max(query.pageSize ?? 20, 1), 100);
    const skip = (page - 1) * pageSize;

    const where: Prisma.UserProductWhereInput = {
      businessId,
      ...(query.status ? { status: query.status } : {}),
    };

    const [items, total] = await Promise.all([
      this.prisma.userProduct.findMany({
        where,
        orderBy: { createdAt: 'desc' },
        skip,
        take: pageSize,
        include: userProductAdminListInclude,
      }),
      this.prisma.userProduct.count({ where }),
    ]);

    const categoryByEntity = await this.loadCategoriesForProducts(
      businessId,
      items.map((item) => item.id),
    );

    return {
      items: items.map((item) =>
        this.serializeAdminListItem(
          item,
          categoryByEntity.get(item.id.toString()),
        ),
      ),
      total,
      page,
      pageSize,
    };
  }

  async adminGetOne(
    businessIdRaw: string,
    productIdRaw: string,
    actor: AuthUser,
  ) {
    const businessId = BigInt(businessIdRaw);
    const productId = BigInt(productIdRaw);
    await this.assertAdminAccess(businessId, actor, 'user_products.read');

    const product = await this.prisma.userProduct.findFirst({
      where: { id: productId, businessId },
      include: userProductAdminDetailInclude,
    });

    if (!product) {
      throw new NotFoundException('User product not found');
    }

    const categoryByEntity = await this.loadCategoriesForProducts(businessId, [
      product.id,
    ]);
    const gallery = await this.loadGalleryAttachments(businessId, product.id);

    return {
      product: this.serializeAdminDetail(
        product,
        categoryByEntity.get(product.id.toString()),
        gallery,
      ),
    };
  }

  async adminCreate(
    businessIdRaw: string,
    dto: CreateUserProductDto,
    actor: AuthUser,
  ) {
    const businessId = BigInt(businessIdRaw);
    await this.assertAdminAccess(businessId, actor, 'user_products.create');
    return this.createForUser(businessId, dto, actor.id);
  }

  async adminUpdate(
    businessIdRaw: string,
    productIdRaw: string,
    dto: UpdateUserProductDto,
    actor: AuthUser,
  ) {
    const businessId = BigInt(businessIdRaw);
    const productId = BigInt(productIdRaw);
    await this.assertAdminAccess(businessId, actor, 'user_products.update');

    const existing = await this.prisma.userProduct.findFirst({
      where: { id: productId, businessId },
      select: {
        id: true,
        title: true,
        slug: true,
        metadata: true,
        userId: true,
        featuredMediaId: true,
      },
    });

    if (!existing) {
      throw new NotFoundException('User product not found');
    }

    return this.updateExisting(businessId, productId, dto, existing);
  }

  async adminUpdateStatus(
    businessIdRaw: string,
    productIdRaw: string,
    dto: UpdateUserProductStatusDto,
    actor: AuthUser,
  ) {
    const businessId = BigInt(businessIdRaw);
    const productId = BigInt(productIdRaw);
    await this.assertAdminAccess(businessId, actor, 'user_products.update');

    const existing = await this.prisma.userProduct.findFirst({
      where: { id: productId, businessId },
      select: { id: true, status: true, publishedAt: true },
    });

    if (!existing) {
      throw new NotFoundException('User product not found');
    }

    const status = dto.status;
    const publishedAt =
      status === ContentStatus.published
        ? existing.publishedAt ?? new Date()
        : null;

    const updated = await this.prisma.userProduct.update({
      where: { id: productId },
      data: { status, publishedAt },
      include: userProductAdminListInclude,
    });

    const categoryByEntity = await this.loadCategoriesForProducts(businessId, [
      updated.id,
    ]);

    await this.sitemap.invalidateForBusiness(businessId);

    return {
      message: 'User product status updated successfully',
      product: this.serializeAdminListItem(
        updated,
        categoryByEntity.get(updated.id.toString()),
      ),
    };
  }

  async adminPromote(
    businessIdRaw: string,
    productIdRaw: string,
    actor: AuthUser,
  ) {
    const businessId = BigInt(businessIdRaw);
    const productId = BigInt(productIdRaw);
    await this.assertAdminAccess(businessId, actor, 'user_products.update');

    const product = await this.prisma.userProduct.findFirst({
      where: { id: productId, businessId },
      include: userProductAdminListInclude,
    });

    if (!product) {
      throw new NotFoundException('User product not found');
    }

    const metadata = this.asRecord(product.metadata);
    const nextMetadata: Prisma.InputJsonValue = {
      ...metadata,
      promoted: true,
      promotedAt: new Date().toISOString(),
    };

    const updated = await this.prisma.userProduct.update({
      where: { id: productId },
      data: { metadata: nextMetadata },
      include: userProductAdminListInclude,
    });

    const categoryByEntity = await this.loadCategoriesForProducts(businessId, [
      updated.id,
    ]);

    return {
      message: 'User product promoted successfully',
      product: this.serializeAdminListItem(
        updated,
        categoryByEntity.get(updated.id.toString()),
      ),
    };
  }

  async adminRemove(
    businessIdRaw: string,
    productIdRaw: string,
    actor: AuthUser,
  ) {
    const businessId = BigInt(businessIdRaw);
    const productId = BigInt(productIdRaw);
    await this.assertAdminAccess(businessId, actor, 'user_products.delete');

    const product = await this.prisma.userProduct.findFirst({
      where: { id: productId, businessId },
      select: { id: true },
    });

    if (!product) {
      throw new NotFoundException('User product not found');
    }

    await this.prisma.$transaction(async (tx) => {
      await tx.categoryAssignment.deleteMany({
        where: {
          businessId,
          entityType: MediaEntityType.user_product,
          entityId: productId,
        },
      });
      await tx.userProduct.delete({ where: { id: productId } });
    });

    await this.sitemap.invalidateForBusiness(businessId);

    return { message: 'User product deleted successfully' };
  }

  async listCategoriesForAdmin(businessIdRaw: string, actor: AuthUser) {
    const businessId = BigInt(businessIdRaw);
    await this.assertAdminAccess(businessId, actor, 'user_products.read');
    return this.listProductCategories(businessId);
  }

  async getCategoryTechnicalFormForAdmin(
    businessIdRaw: string,
    categoryIdRaw: string,
    actor: AuthUser,
  ) {
    const businessId = BigInt(businessIdRaw);
    const categoryId = BigInt(categoryIdRaw);
    await this.assertAdminAccess(businessId, actor, 'user_products.read');
    await this.assertProductCategory(businessId, categoryId);

    const form = await this.technicalFormService.getFormForCategory(
      businessId,
      categoryId,
    );

    return { form };
  }

  async listCategories(businessIdRaw: string, actor: AuthUser) {
    const businessId = BigInt(businessIdRaw);
    await this.assertCustomerAccess(businessId, actor);
    return this.listProductCategories(businessId);
  }

  async getCategoryTechnicalForm(
    businessIdRaw: string,
    categoryIdRaw: string,
    actor: AuthUser,
  ) {
    const businessId = BigInt(businessIdRaw);
    const categoryId = BigInt(categoryIdRaw);
    await this.assertCustomerAccess(businessId, actor);
    await this.assertProductCategory(businessId, categoryId);

    const form = await this.technicalFormService.getFormForCategory(
      businessId,
      categoryId,
    );

    return { form };
  }

  private validateTechnicalValues(
    fields: FormField[],
    values: UserProductTechnicalValueDto[],
  ) {
    if (!fields.length) {
      if (values.length) {
        throw new BadRequestException(
          'This category has no technical form fields',
        );
      }
      return;
    }

    const fieldMap = new Map(fields.map((field) => [field.id, field]));
    const submittedIds = new Set<string>();

    for (const entry of values) {
      if (submittedIds.has(entry.fieldId)) {
        throw new BadRequestException(
          `Duplicate technical value for field "${entry.fieldId}"`,
        );
      }
      submittedIds.add(entry.fieldId);

      const field = fieldMap.get(entry.fieldId);
      if (!field) {
        throw new BadRequestException(
          `Unknown technical field "${entry.fieldId}"`,
        );
      }

      this.validateFieldEntry(field, entry);
    }

    for (const field of fields) {
      if (!field.isRequired) {
        continue;
      }
      const entry = values.find((item) => item.fieldId === field.id);
      if (!entry || !this.hasFieldValue(field, entry)) {
        throw new BadRequestException(
          `Required field "${field.label}" is missing`,
        );
      }
    }
  }

  private validateFieldEntry(
    field: FormField,
    entry: UserProductTechnicalValueDto,
  ) {
    if (field.type === 'text' || field.type === 'textarea') {
      if (entry.optionId || entry.optionIds?.length) {
        throw new BadRequestException(
          `Field "${field.label}" expects a text value`,
        );
      }
      const text = entry.textValue?.trim() ?? '';
      if (field.isRequired && !text) {
        throw new BadRequestException(
          `Required field "${field.label}" cannot be empty`,
        );
      }
      return;
    }

    if (field.type === 'select') {
      if (entry.textValue || entry.optionIds?.length) {
        throw new BadRequestException(
          `Field "${field.label}" expects a single optionId`,
        );
      }
      if (!entry.optionId) {
        if (field.isRequired) {
          throw new BadRequestException(
            `Required field "${field.label}" cannot be empty`,
          );
        }
        return;
      }
      this.findOptionById(field, entry.optionId);
      return;
    }

    if (entry.textValue || entry.optionId) {
      throw new BadRequestException(
        `Field "${field.label}" expects optionIds`,
      );
    }
    const optionIds = entry.optionIds ?? [];
    if (!optionIds.length) {
      if (field.isRequired) {
        throw new BadRequestException(
          `Required field "${field.label}" cannot be empty`,
        );
      }
      return;
    }
    for (const optionId of optionIds) {
      this.findOptionById(field, optionId);
    }
  }

  private hasFieldValue(
    field: FormField,
    entry: UserProductTechnicalValueDto,
  ): boolean {
    if (field.type === 'text' || field.type === 'textarea') {
      return Boolean(entry.textValue?.trim());
    }
    if (field.type === 'select') {
      return Boolean(entry.optionId);
    }
    return Boolean(entry.optionIds?.length);
  }

  private findOptionById(field: FormField, optionId: string) {
    const option = field.options.find((item) => item.id === optionId);
    if (!option) {
      throw new BadRequestException(
        `Invalid option "${optionId}" for field "${field.label}"`,
      );
    }
    return option;
  }

  private async saveTechnicalValues(
    tx: Prisma.TransactionClient,
    businessId: bigint,
    userProductId: bigint,
    fields: FormField[],
    values: UserProductTechnicalValueDto[],
  ) {
    const fieldMap = new Map(fields.map((field) => [field.id, field]));

    for (const entry of values) {
      const field = fieldMap.get(entry.fieldId);
      if (!field) {
        continue;
      }

      if (!this.hasFieldValue(field, entry)) {
        continue;
      }

      const fieldId = BigInt(field.id);

      if (field.type === 'text' || field.type === 'textarea') {
        await tx.userProductTechnicalFieldValue.create({
          data: {
            businessId,
            userProductId,
            fieldId,
            textValue: entry.textValue!.trim(),
          },
        });
        continue;
      }

      if (field.type === 'select') {
        await tx.userProductTechnicalFieldValue.create({
          data: {
            businessId,
            userProductId,
            fieldId,
            optionId: BigInt(entry.optionId!),
          },
        });
        continue;
      }

      const fieldValue = await tx.userProductTechnicalFieldValue.create({
        data: {
          businessId,
          userProductId,
          fieldId,
        },
      });

      for (const optionId of entry.optionIds ?? []) {
        await tx.userProductTechnicalFieldValueOption.create({
          data: {
            fieldValueId: fieldValue.id,
            optionId: BigInt(optionId),
          },
        });
      }
    }
  }

  private async loadCategoriesForProducts(
    businessId: bigint,
    productIds: bigint[],
  ) {
    const map = new Map<
      string,
      { id: bigint; name: string; nameFa: string | null }
    >();

    if (!productIds.length) {
      return map;
    }

    const assignments = await this.prisma.categoryAssignment.findMany({
      where: {
        businessId,
        entityType: MediaEntityType.user_product,
        entityId: { in: productIds },
      },
      include: {
        category: {
          select: { id: true, name: true, nameFa: true },
        },
      },
    });

    for (const assignment of assignments) {
      map.set(assignment.entityId.toString(), assignment.category);
    }

    return map;
  }

  private serializeListItem(
    product: UserProductListRow,
    category?: { id: bigint; name: string; nameFa: string | null } | null,
  ) {
    const content = this.asRecord(product.content);
    const metadata = this.asRecord(product.metadata);
    const titleEn =
      typeof content.titleEn === 'string' ? content.titleEn : null;
    const priceByExpert = metadata.priceByExpert === true;
    const promoted = metadata.promoted === true;

    return {
      id: product.id.toString(),
      slug: product.slug,
      pathSlug: buildUserProductSlug(product.title, titleEn),
      title: product.title,
      titleFa: product.title,
      titleEn,
      description: product.description,
      price: product.price === null ? null : Number(product.price),
      priceCurrency: product.priceCurrency,
      priceByExpert,
      promoted,
      ...readSeoMetaFromMetadata(metadata),
      status: product.status,
      condition: product.condition,
      deliveryNote: product.deliveryNote,
      technicalNotes: product.technicalNotes,
      cityId: product.cityId.toString(),
      countryId: product.countryId.toString(),
      cityName: product.city.nameEn,
      cityNameFa: product.city.nameFa,
      countryName: product.country.nameEn,
      countryNameFa: product.country.nameFa,
      imageUrl: product.featuredMedia?.publicUrl ?? null,
      categoryId: category?.id.toString() ?? null,
      categoryName: category?.name ?? null,
      categoryNameFa: category?.nameFa ?? null,
      createdAt: product.createdAt,
      publishedAt: product.publishedAt,
    };
  }

  private serializeDetail(
    product: UserProductDetailRow,
    category?: { id: bigint; name: string; nameFa: string | null } | null,
    gallery: { mediaId: bigint; publicUrl: string }[] = [],
  ) {
    const base = this.serializeListItem(
      product as UserProductListRow,
      category,
    );
    const technicalValues: UserProductTechnicalValueDto[] = [];

    for (const value of product.technicalFieldValues) {
      const fieldId = value.fieldId.toString();
      if (value.textValue != null) {
        technicalValues.push({ fieldId, textValue: value.textValue });
        continue;
      }
      if (value.optionId != null) {
        technicalValues.push({
          fieldId,
          optionId: value.optionId.toString(),
        });
        continue;
      }
      if (value.selectedOptions.length) {
        technicalValues.push({
          fieldId,
          optionIds: value.selectedOptions.map((item) =>
            item.optionId.toString(),
          ),
        });
      }
    }

    return {
      ...base,
      countryId: product.countryId.toString(),
      cityId: product.cityId.toString(),
      countrySlug: product.country.slug,
      featuredMediaId: product.featuredMediaId?.toString() ?? null,
      galleryMediaIds: gallery.map((item) => item.mediaId.toString()),
      images: gallery.map((item) => ({
        mediaId: item.mediaId.toString(),
        url: item.publicUrl,
      })),
      technicalValues,
    };
  }

  private serializeAdminListItem(
    product: UserProductAdminListRow,
    category?: { id: bigint; name: string; nameFa: string | null } | null,
  ) {
    const base = this.serializeListItem(
      product as UserProductListRow,
      category,
    );
    const owner = this.formatOwnerNames(product.user);
    return {
      ...base,
      ownerId: product.user.id.toString(),
      ownerName: owner.nameEn,
      ownerNameFa: owner.nameFa,
      ownerCell: product.user.cellNumber,
    };
  }

  private serializeAdminDetail(
    product: UserProductAdminDetailRow,
    category?: { id: bigint; name: string; nameFa: string | null } | null,
    gallery: { mediaId: bigint; publicUrl: string }[] = [],
  ) {
    const detail = this.serializeDetail(
      product as UserProductDetailRow,
      category,
      gallery,
    );
    const owner = this.formatOwnerNames(product.user);
    return {
      ...detail,
      ownerId: product.user.id.toString(),
      ownerName: owner.nameEn,
      ownerNameFa: owner.nameFa,
      ownerCell: product.user.cellNumber,
    };
  }

  private formatOwnerNames(user: {
    firstName: string | null;
    lastName: string | null;
    firstNameEn: string | null;
    lastNameEn: string | null;
    cellNumber: string;
  }) {
    const nameFa = [user.firstName, user.lastName]
      .filter(Boolean)
      .join(' ')
      .trim();
    const nameEn = [user.firstNameEn, user.lastNameEn]
      .filter(Boolean)
      .join(' ')
      .trim();
    const fallback = nameFa || nameEn || user.cellNumber;
    return {
      nameFa: nameFa || fallback,
      nameEn: nameEn || fallback,
    };
  }

  private async listProductCategories(businessId: bigint) {
    const items = await this.prisma.category.findMany({
      where: {
        businessId,
        entityType: MediaEntityType.product,
        isActive: true,
      },
      orderBy: [{ sortOrder: 'asc' }, { name: 'asc' }],
      select: {
        id: true,
        name: true,
        nameFa: true,
        parentId: true,
      },
    });

    return {
      items: items.map((item) => ({
        id: item.id.toString(),
        name: item.name,
        nameFa: item.nameFa,
        parentId: item.parentId?.toString() ?? null,
      })),
    };
  }

  private asRecord(value: unknown): Record<string, unknown> {
    if (value && typeof value === 'object' && !Array.isArray(value)) {
      return value as Record<string, unknown>;
    }
    return {};
  }

  private async ensureUniqueSlug(
    businessId: bigint,
    baseSlug: string,
    excludeId?: bigint,
  ) {
    let slug = baseSlug;
    let suffix = 1;

    while (true) {
      const existing = await this.prisma.userProduct.findFirst({
        where: {
          businessId,
          slug,
          ...(excludeId ? { id: { not: excludeId } } : {}),
        },
        select: { id: true },
      });

      if (!existing) {
        return slug;
      }

      suffix += 1;
      slug = `${baseSlug}-${suffix}`;
    }
  }

  private async assertProductCategory(businessId: bigint, categoryId: bigint) {
    const category = await this.prisma.category.findFirst({
      where: {
        id: categoryId,
        businessId,
        entityType: MediaEntityType.product,
        isActive: true,
      },
    });

    if (!category) {
      throw new NotFoundException('Product category not found');
    }

    return category;
  }

  private async assertCountryAndCity(countryId: bigint, cityId: bigint) {
    const [country, city] = await Promise.all([
      this.prisma.city.findFirst({
        where: { id: countryId, level: CityLevel.country, isActive: true },
      }),
      this.prisma.city.findFirst({
        where: { id: cityId, level: CityLevel.city, isActive: true },
      }),
    ]);

    if (!country) {
      throw new BadRequestException('Country not found');
    }
    if (!city) {
      throw new BadRequestException('City not found');
    }

    let cursor: { id: bigint; parentId: bigint | null; level: CityLevel } | null =
      city;
    let belongsToCountry = false;

    while (cursor) {
      if (cursor.id === countryId) {
        belongsToCountry = true;
        break;
      }
      if (!cursor.parentId) {
        break;
      }
      cursor = await this.prisma.city.findFirst({
        where: { id: cursor.parentId },
        select: { id: true, parentId: true, level: true },
      });
    }

    if (!belongsToCountry) {
      throw new BadRequestException('City does not belong to the selected country');
    }
  }

  private async buildPublicWhere(
    businessId: bigint,
    query: ListPublicUserProductsDto,
  ): Promise<Prisma.UserProductWhereInput> {
    let entityIds: bigint[] | undefined;

    if (query.categoryId) {
      const assignments = await this.prisma.categoryAssignment.findMany({
        where: {
          businessId,
          categoryId: BigInt(query.categoryId),
          entityType: MediaEntityType.user_product,
        },
        select: { entityId: true },
      });

      entityIds = assignments.map((item) => item.entityId);
      if (entityIds.length === 0) {
        return { id: { in: [] } };
      }
    }

    const search = (query.q ?? query.name)?.trim();
    const and: Prisma.UserProductWhereInput[] = [];

    if (search) {
      and.push({
        OR: [
          { title: { contains: search, mode: 'insensitive' } },
          { description: { contains: search, mode: 'insensitive' } },
        ],
      });
    }

    if (query.promoted === true) {
      and.push({
        metadata: {
          path: ['promoted'],
          equals: true,
        },
      });
    }

    return {
      businessId,
      status: ContentStatus.published,
      ...(entityIds ? { id: { in: entityIds } } : {}),
      ...(query.cityId ? { cityId: BigInt(query.cityId) } : {}),
      ...(query.countryId ? { countryId: BigInt(query.countryId) } : {}),
      ...(query.condition ? { condition: query.condition } : {}),
      ...(and.length ? { AND: and } : {}),
    };
  }

  private async assertMediaBelongsToBusiness(
    businessId: bigint,
    mediaId: bigint,
  ) {
    const media = await this.prisma.media.findFirst({
      where: { id: mediaId, businessId },
    });
    if (!media) {
      throw new BadRequestException('Media not found for this business');
    }
  }

  private async resolveGalleryMediaIds(businessId: bigint, rawIds: string[]) {
    const ids = rawIds.map((id) => BigInt(id));
    for (const mediaId of ids) {
      await this.assertMediaBelongsToBusiness(businessId, mediaId);
    }
    return ids;
  }

  private async syncGalleryAttachments(
    tx: Prisma.TransactionClient,
    businessId: bigint,
    productId: bigint,
    mediaIds: bigint[],
  ) {
    await tx.mediaAttachment.deleteMany({
      where: {
        businessId,
        entityType: MediaEntityType.user_product,
        entityId: productId,
        isFeatured: false,
      },
    });

    for (const [index, mediaId] of mediaIds.entries()) {
      await tx.mediaAttachment.create({
        data: {
          businessId,
          mediaId,
          entityType: MediaEntityType.user_product,
          entityId: productId,
          sortOrder: index,
          isFeatured: false,
        },
      });
    }
  }

  private async loadGalleryAttachments(businessId: bigint, productId: bigint) {
    const attachments = await this.prisma.mediaAttachment.findMany({
      where: {
        businessId,
        entityType: MediaEntityType.user_product,
        entityId: productId,
        isFeatured: false,
      },
      include: { media: true },
      orderBy: { sortOrder: 'asc' },
    });

    return attachments.map((item) => ({
      mediaId: item.mediaId,
      publicUrl: item.media.publicUrl,
    }));
  }

  private async assertAdminAccess(
    businessId: bigint,
    actor: AuthUser,
    permission: string,
  ) {
    if (await this.permissions.isSuperAdmin(actor.id)) {
      return;
    }

    const allowed = await this.permissions.hasBusinessPermission(
      actor.id,
      businessId,
      permission,
    );
    if (!allowed) {
      throw new ForbiddenException('Insufficient permissions');
    }
  }

  private async assertCustomerAccess(businessId: bigint, actor: AuthUser) {
    if (await this.permissions.isSuperAdmin(actor.id)) {
      return;
    }

    const membership = await this.prisma.businessCustomer.findUnique({
      where: {
        businessId_userId: { businessId, userId: actor.id },
      },
    });

    if (!membership) {
      throw new ForbiddenException('You are not a customer of this business');
    }
  }
}