import {
  BadRequestException,
  ConflictException,
  ForbiddenException,
  Injectable,
  NotFoundException,
} from '@nestjs/common';
import { Prisma } from '@prisma/client';
import * as bcrypt from 'bcrypt';
import { PermissionsService } from '../auth/permissions.service';
import { PrismaService } from '../prisma/prisma.service';
import { AuthUser } from '../auth/auth.types';
import { AddDomainDto } from './dto/add-domain.dto';
import { UpdateDomainDto } from './dto/update-domain.dto';
import { CreateBusinessDto } from './dto/create-business.dto';
import { DisableBusinessDto } from './dto/disable-business.dto';
import { UpdateBusinessDto } from './dto/update-business.dto';
import { ListBusinessesDto } from './dto/list-businesses.dto';
import { SearchBusinessesDto } from './dto/search-businesses.dto';
import { MigrateFromOldDto } from './dto/migrate-from-old.dto';
import { PurgeBusinessDataDto } from './dto/purge-business-data.dto';
import { LegacyMigrateService } from './legacy-migrate.service';
import { LegacyPurgeService } from './legacy-purge.service';
import { normalizeBusinessPrimaryColorId } from '../business-settings/business-primary-colors';
import type { BusinessPrimaryColorId } from '../business-settings/business-primary-colors';

type BusinessRow = {
  id: bigint;
  name: string;
  nameFa: string | null;
  about: string | null;
  slug: string;
  createdAt: Date;
  isActive: boolean;
  oldBusinessId: bigint | null;
  domainId: bigint | null;
  domain: string | null;
  sslEnabled: boolean | null;
  ownerUserId: bigint | null;
  ownerName: string | null;
  ownerCellNumber: string | null;
  primaryColor: string | null;
};

function slugify(value: string) {
  return value
    .trim()
    .toLowerCase()
    .replace(/[^a-z0-9]+/g, '-')
    .replace(/(^-|-$)/g, '');
}

@Injectable()
export class BusinessAdminService {
  constructor(
    private readonly prisma: PrismaService,
    private readonly permissions: PermissionsService,
    private readonly legacyMigrate: LegacyMigrateService,
    private readonly legacyPurge: LegacyPurgeService,
  ) {}

  private async assertSuperAdmin(actor: AuthUser) {
    if (!(await this.permissions.isSuperAdmin(actor.id))) {
      throw new ForbiddenException('Super admin access required');
    }
  }

  async list(query: ListBusinessesDto, actor: AuthUser) {
    await this.assertSuperAdmin(actor);

    const page = query.page ?? 1;
    const pageSize = query.pageSize ?? 10;
    const skip = (page - 1) * pageSize;

    const nameLike = query.name ? `%${query.name.trim()}%` : null;
    const domainLike = query.domain ? `%${query.domain.trim()}%` : null;
    const categoryLike = query.category ? `%${query.category.trim()}%` : null;

    const where = Prisma.sql`
      WHERE 1=1
      ${nameLike ? Prisma.sql`AND (b.name ILIKE ${nameLike} OR b.name_fa ILIKE ${nameLike})` : Prisma.empty}
      ${domainLike ? Prisma.sql`
        AND EXISTS (
          SELECT 1 FROM domains d
          WHERE d.business_id = b.id AND d.host ILIKE ${domainLike}
        )
      ` : Prisma.empty}
      ${categoryLike ? Prisma.sql`
        AND EXISTS (
          SELECT 1
          FROM business_category_assignments bca
          JOIN business_categories bc ON bc.id = bca.category_id
          WHERE bca.business_id = b.id
            AND (bc.slug ILIKE ${categoryLike} OR bc.name ILIKE ${categoryLike})
        )
      ` : Prisma.empty}
    `;

    const [items, totalRow] = await Promise.all([
      this.prisma.$queryRaw<BusinessRow[]>(Prisma.sql`
        SELECT
          b.id AS "id",
          b.name AS "name",
          b.name_fa AS "nameFa",
          b.about AS "about",
          b.slug AS "slug",
          b.created_at AS "createdAt",
          b.is_active AS "isActive",
          b.old_business_id AS "oldBusinessId",
          dom.id AS "domainId",
          dom.host AS "domain",
          dom.ssl_enabled AS "sslEnabled",
          own."ownerUserId" AS "ownerUserId",
          own."ownerName" AS "ownerName",
          own."ownerCellNumber" AS "ownerCellNumber",
          b.settings->'branding'->>'primaryColor' AS "primaryColor"
        FROM businesses b
        LEFT JOIN LATERAL (
          SELECT d.id, d.host, d.ssl_enabled
          FROM domains d
          WHERE d.business_id = b.id
          ORDER BY d.is_primary DESC, d.created_at DESC
          LIMIT 1
        ) dom ON TRUE
        LEFT JOIN LATERAL (
          SELECT
            u.id AS "ownerUserId",
            (u.first_name || ' ' || u.last_name) AS "ownerName",
            u.cell_number AS "ownerCellNumber"
          FROM business_users bu
          JOIN users u ON u.id = bu.user_id
          WHERE bu.business_id = b.id AND bu.is_owner = TRUE
          LIMIT 1
        ) own ON TRUE
        ${where}
        ORDER BY b.created_at DESC
        LIMIT ${pageSize} OFFSET ${skip}
      `),
      this.prisma.$queryRaw<{ total: number }[]>(Prisma.sql`
        SELECT COUNT(*)::int AS "total"
        FROM businesses b
        ${where}
      `),
    ]);

    return {
      items: items.map((item) => ({
        ...item,
        primaryColor: normalizeBusinessPrimaryColorId(
          item.primaryColor,
        ) as BusinessPrimaryColorId,
      })),
      total: totalRow[0]?.total ?? 0,
      page,
      pageSize,
    };
  }

  async search(query: SearchBusinessesDto, actor: AuthUser) {
    await this.assertSuperAdmin(actor);

    const q = query.q.trim();
    const limit = Math.min(Math.max(query.limit ?? 20, 1), 50);
    const like = `%${q}%`;

    const items = await this.prisma.$queryRaw<
      {
        id: bigint;
        name: string;
        nameFa: string | null;
        slug: string;
      }[]
    >(Prisma.sql`
      SELECT DISTINCT
        b.id AS "id",
        b.name AS "name",
        b.name_fa AS "nameFa",
        b.slug AS "slug"
      FROM businesses b
      LEFT JOIN domains d ON d.business_id = b.id
      WHERE b.is_active = TRUE
        AND (
          b.name ILIKE ${like}
          OR b.name_fa ILIKE ${like}
          OR b.slug ILIKE ${like}
          OR d.host ILIKE ${like}
        )
      ORDER BY b.name ASC
      LIMIT ${limit}
    `);

    return {
      items: items.map((business) => ({
        id: business.id,
        name: business.name,
        nameFa: business.nameFa,
        slug: business.slug,
        label: this.formatBusinessLabel(business),
      })),
    };
  }

  async listStaff(businessIdRaw: string, actor: AuthUser) {
    await this.assertSuperAdmin(actor);

    const businessId = BigInt(businessIdRaw);
    const business = await this.prisma.business.findUnique({
      where: { id: businessId },
    });

    if (!business) {
      throw new NotFoundException('Business not found');
    }

    const members = await this.prisma.businessUser.findMany({
      where: { businessId },
      include: {
        user: {
          select: {
            id: true,
            cellNumber: true,
            firstName: true,
            lastName: true,
            email: true,
            cellVerifiedAt: true,
            isActive: true,
          },
        },
        role: true,
        inviter: { select: { id: true, firstName: true, lastName: true } },
      },
      orderBy: [{ isOwner: 'desc' }, { createdAt: 'asc' }],
    });

    return {
      items: members.map((member) => ({
        id: member.id,
        userId: member.user.id,
        cellNumber: member.user.cellNumber,
        firstName: member.user.firstName,
        lastName: member.user.lastName,
        email: member.user.email,
        isActive: member.user.isActive,
        isVerified: member.user.cellVerifiedAt !== null,
        isOwner: member.isOwner,
        teamRole: member.isOwner ? 'business_owner' : member.role?.slug ?? null,
        invitedBy: member.inviter,
        createdAt: member.createdAt,
      })),
    };
  }

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

    const business = await this.prisma.business.findUnique({
      where: { id: businessId },
      include: {
        categoryAssignments: {
          include: { category: true },
        },
        businessUsers: {
          where: { isOwner: true },
          include: { user: true },
          take: 1,
        },
        domains: { orderBy: [{ isPrimary: 'desc' }, { createdAt: 'asc' }] },
      },
    });

    if (!business) {
      throw new NotFoundException('Business not found');
    }

    return this.serializeBusiness(business);
  }

  async create(dto: CreateBusinessDto, actor: AuthUser) {
    await this.assertSuperAdmin(actor);

    const slug = dto.slug?.trim() || slugify(dto.name);
    if (!slug) {
      throw new BadRequestException('Could not generate slug from name');
    }

    await this.assertSlugAvailable(slug);
    await this.validateCategoryIds(dto.categoryIds);

    if (dto.oldBusinessId !== undefined) {
      await this.assertOldBusinessIdAvailable(BigInt(dto.oldBusinessId));
    }

    let business;
    try {
      business = await this.prisma.$transaction(async (tx) => {
        const owner = await this.createOwnerUser(tx, dto);

        const created = await tx.business.create({
          data: {
            name: dto.name.trim(),
            nameFa: dto.nameFa.trim(),
            about: dto.about?.trim() ?? null,
            slug,
            oldBusinessId:
              dto.oldBusinessId !== undefined ? BigInt(dto.oldBusinessId) : undefined,
          },
        });

        await tx.businessCategoryAssignment.createMany({
          data: dto.categoryIds.map((id) => ({
            businessId: created.id,
            categoryId: BigInt(id),
          })),
        });

        await this.assignOwner(tx, created.id, owner.id, actor.id);

        return created;
      });
    } catch (err) {
      if (
        err instanceof Prisma.PrismaClientKnownRequestError &&
        err.code === 'P2002'
      ) {
        throw new ConflictException('Business slug or old business id is already taken');
      }
      throw err;
    }

    return this.getOne(business.id.toString(), actor);
  }

  async update(businessIdRaw: string, dto: UpdateBusinessDto, actor: AuthUser) {
    await this.assertSuperAdmin(actor);

    const businessId = BigInt(businessIdRaw);
    const business = await this.prisma.business.findUnique({
      where: { id: businessId },
    });

    if (!business) {
      throw new NotFoundException('Business not found');
    }

    const nextName = dto.name?.trim() ?? business.name;
    const nextNameFa = dto.nameFa?.trim() ?? business.nameFa ?? business.name;
    const nextSlug =
      dto.slug?.trim() ?? (dto.name ? slugify(dto.name) : business.slug);

    if (nextSlug !== business.slug) {
      await this.assertSlugAvailable(nextSlug, businessId);
    }

    if (dto.categoryIds) {
      await this.validateCategoryIds(dto.categoryIds);
    }

    if (dto.ownerUserId !== undefined && dto.ownerUserId !== null) {
      await this.findOwnerUser(dto.ownerUserId);
    }

    if (dto.oldBusinessId !== undefined && dto.oldBusinessId !== null) {
      await this.assertOldBusinessIdAvailable(BigInt(dto.oldBusinessId), businessId);
    }

    await this.prisma.$transaction(async (tx) => {
      await tx.business.update({
        where: { id: businessId },
        data: {
          name: nextName,
          nameFa: nextNameFa,
          about: dto.about !== undefined ? dto.about.trim() || null : undefined,
          slug: nextSlug,
          ...(dto.oldBusinessId !== undefined
            ? {
                oldBusinessId:
                  dto.oldBusinessId === null ? null : BigInt(dto.oldBusinessId),
              }
            : {}),
        },
      });

      if (dto.categoryIds) {
        await tx.businessCategoryAssignment.deleteMany({ where: { businessId } });
        await tx.businessCategoryAssignment.createMany({
          data: dto.categoryIds.map((id) => ({
            businessId,
            categoryId: BigInt(id),
          })),
        });
      }

      if (dto.ownerUserId !== undefined && dto.ownerUserId !== null) {
        await tx.businessUser.deleteMany({
          where: { businessId, isOwner: true },
        });
        await this.assignOwner(tx, businessId, BigInt(dto.ownerUserId), actor.id);
      }
    });

    return this.getOne(businessIdRaw, actor);
  }

  async addDomain(businessIdRaw: string, dto: AddDomainDto, actor: AuthUser) {
    await this.assertSuperAdmin(actor);

    const businessId = BigInt(businessIdRaw);
    const host = dto.host.trim();

    if (!host) {
      throw new BadRequestException('host is required');
    }

    const business = await this.prisma.business.findUnique({ where: { id: businessId } });
    if (!business) {
      throw new NotFoundException('Business not found');
    }

    const hasPrimary = await this.prisma.domain.findFirst({
      where: { businessId, isPrimary: true },
      select: { id: true },
    });

    const isPrimary = dto.isPrimary ?? !hasPrimary;

    return this.prisma.domain.create({
      data: {
        businessId,
        host,
        isPrimary,
        isVerified: false,
        sslEnabled: false,
      },
    });
  }

  async updateDomain(
    businessIdRaw: string,
    domainIdRaw: string,
    dto: UpdateDomainDto,
    actor: AuthUser,
  ) {
    await this.assertSuperAdmin(actor);

    const businessId = BigInt(businessIdRaw);
    const domainId = BigInt(domainIdRaw);
    const host = dto.host.trim();

    if (!host) {
      throw new BadRequestException('host is required');
    }

    const domain = await this.prisma.domain.findFirst({
      where: { id: domainId, businessId },
    });

    if (!domain) {
      throw new NotFoundException('Domain not found');
    }

    const existing = await this.prisma.domain.findUnique({ where: { host } });
    if (existing && existing.id !== domainId) {
      throw new ConflictException('Domain host is already taken');
    }

    return this.prisma.domain.update({
      where: { id: domainId },
      data: { host },
    });
  }

  async disable(businessIdRaw: string, dto: DisableBusinessDto, actor: AuthUser) {
    await this.assertSuperAdmin(actor);

    const businessId = BigInt(businessIdRaw);
    const business = await this.prisma.business.findUnique({ where: { id: businessId } });
    if (!business) {
      throw new NotFoundException('Business not found');
    }

    return this.prisma.business.update({
      where: { id: businessId },
      data: { isActive: dto.isActive },
    });
  }

  async remove(businessIdRaw: string, actor: AuthUser) {
    await this.assertSuperAdmin(actor);

    const businessId = BigInt(businessIdRaw);
    const business = await this.prisma.business.findUnique({ where: { id: businessId } });
    if (!business) {
      throw new NotFoundException('Business not found');
    }

    await this.prisma.business.delete({ where: { id: businessId } });

    return { message: 'Business removed' };
  }

  async migrateFromOld(businessIdRaw: string, dto: MigrateFromOldDto, actor: AuthUser) {
    await this.assertSuperAdmin(actor);

    const businessId = BigInt(businessIdRaw);
    const oldBusinessId = BigInt(dto.oldBusinessId);

    const business = await this.prisma.business.findUnique({
      where: { id: businessId },
    });
    if (!business) {
      throw new NotFoundException('Business not found');
    }

    await this.assertOldBusinessIdAvailable(oldBusinessId, businessId);

    let updated;
    try {
      updated = await this.prisma.business.update({
        where: { id: businessId },
        data: { oldBusinessId },
      });
    } catch (err) {
      if (
        err instanceof Prisma.PrismaClientKnownRequestError &&
        err.code === 'P2002'
      ) {
        throw new ConflictException(
          `Old business id ${dto.oldBusinessId} is already linked to another business`,
        );
      }
      throw err;
    }

    // Data copy for selected entities (portfolio categories implemented first).
    const results = await this.legacyMigrate.migrateEntities(
      businessId,
      oldBusinessId,
      dto.entities,
    );

    const implemented = dto.entities.filter((entity) => {
      const result = results[entity];
      return result && !('status' in result && result.status === 'not_implemented');
    });
    const pending = dto.entities.filter((entity) => {
      const result = results[entity];
      return result && 'status' in result && result.status === 'not_implemented';
    });

    const parts: string[] = [];
    const portfolioCats = results.portfolio_categories;
    if (
      portfolioCats &&
      !('status' in portfolioCats) &&
      'created' in portfolioCats
    ) {
      parts.push(
        `portfolio categories: ${portfolioCats.created} created, ${portfolioCats.skipped} skipped (${portfolioCats.total} total)`,
      );
    }
    const portfolios = results.portfolio;
    if (portfolios && !('status' in portfolios) && 'created' in portfolios) {
      const imgBits = [
        portfolios.imagesCopied != null
          ? `${portfolios.imagesCopied} images copied`
          : null,
        portfolios.imagesResized != null && portfolios.imagesResized > 0
          ? `${portfolios.imagesResized} resized (≤1280px)`
          : null,
        portfolios.titlesUpdated != null && portfolios.titlesUpdated > 0
          ? `${portfolios.titlesUpdated} titles updated`
          : null,
        portfolios.imagesFailed != null && portfolios.imagesFailed > 0
          ? `${portfolios.imagesFailed} images failed`
          : null,
      ].filter(Boolean);
      parts.push(
        `portfolios: ${portfolios.created} created, ${portfolios.skipped} skipped (${portfolios.total} total)` +
          (imgBits.length ? `; ${imgBits.join(', ')}` : ''),
      );
    }
    const blogCats = results.blog_categories;
    if (blogCats && !('status' in blogCats) && 'created' in blogCats) {
      parts.push(
        `blog categories: ${blogCats.created} created, ${blogCats.skipped} skipped (${blogCats.total} total)`,
      );
    }
    const blogs = results.blog;
    if (blogs && !('status' in blogs) && 'created' in blogs) {
      const imgBits = [
        blogs.imagesCopied != null ? `${blogs.imagesCopied} images copied` : null,
        blogs.imagesResized != null && blogs.imagesResized > 0
          ? `${blogs.imagesResized} resized (≤1280px)`
          : null,
        blogs.imagesFailed != null && blogs.imagesFailed > 0
          ? `${blogs.imagesFailed} images failed`
          : null,
      ].filter(Boolean);
      parts.push(
        `blogs: ${blogs.created} created, ${blogs.skipped} skipped (${blogs.total} total; articles + news)` +
          (imgBits.length ? `; ${imgBits.join(', ')}` : ''),
      );
    }
    const customerCats = results.customer_categories;
    if (
      customerCats &&
      !('status' in customerCats) &&
      'created' in customerCats
    ) {
      parts.push(
        `customer categories: ${customerCats.created} created, ${customerCats.skipped} skipped (${customerCats.total} total)`,
      );
    }

    const productCats = results.product_categories;
    if (
      productCats &&
      !('status' in productCats) &&
      'created' in productCats
    ) {
      parts.push(
        `product categories: ${productCats.created} created, ${productCats.skipped} skipped (${productCats.total} total)`,
      );
    }

    const customers = results.customer;
    if (customers && !('status' in customers) && 'created' in customers) {
      const skipBits = [
        customers.skippedInvalidCell != null && customers.skippedInvalidCell > 0
          ? `${customers.skippedInvalidCell} invalid/missing cell`
          : null,
        customers.skippedAlreadyLinked != null &&
        customers.skippedAlreadyLinked > 0
          ? `${customers.skippedAlreadyLinked} already linked`
          : null,
        customers.skippedCreateFailed != null &&
        customers.skippedCreateFailed > 0
          ? `${customers.skippedCreateFailed} create failed`
          : null,
      ].filter(Boolean);
      parts.push(
        `customers: ${customers.created} created, ${customers.skipped} skipped (${customers.total} total)` +
          (skipBits.length ? `; ${skipBits.join(', ')}` : ''),
      );
    }

    const products = results.product;
    if (products && !('status' in products) && 'created' in products) {
      const productImageBits = [
        products.imagesCopied != null
          ? `${products.imagesCopied} images copied`
          : null,
        products.imagesResized != null && products.imagesResized > 0
          ? `${products.imagesResized} resized`
          : null,
        products.imagesFailed != null && products.imagesFailed > 0
          ? `${products.imagesFailed} image failures`
          : null,
      ].filter(Boolean);
      parts.push(
        `products: ${products.created} created, ${products.skipped} skipped (${products.total} total)` +
          (productImageBits.length ? `; ${productImageBits.join(', ')}` : ''),
      );
    }
    if (pending.length) {
      parts.push(`not implemented yet: ${pending.join(', ')}`);
    }

    const status =
      implemented.length === 0
        ? ('linked' as const)
        : pending.length > 0
          ? ('partial' as const)
          : ('ok' as const);

    return {
      businessId: updated.id.toString(),
      oldBusinessId: updated.oldBusinessId?.toString() ?? String(dto.oldBusinessId),
      entities: dto.entities,
      status,
      results,
      message:
        parts.length > 0
          ? `Old business linked. ${parts.join('. ')}.`
          : 'Old business id saved.',
    };
  }

  async purgeData(businessIdRaw: string, dto: PurgeBusinessDataDto, actor: AuthUser) {
    await this.assertSuperAdmin(actor);

    const businessId = BigInt(businessIdRaw);
    const business = await this.prisma.business.findUnique({
      where: { id: businessId },
    });
    if (!business) {
      throw new NotFoundException('Business not found');
    }

    const results = await this.legacyPurge.purgeEntities(businessId, dto.entities);

    const implemented = dto.entities.filter((entity) => {
      const result = results[entity];
      return result && !('status' in result && result.status === 'not_implemented');
    });
    const pending = dto.entities.filter((entity) => {
      const result = results[entity];
      return result && 'status' in result && result.status === 'not_implemented';
    });

    const parts: string[] = [];
    const productCats = results.product_categories;
    if (productCats && !('status' in productCats) && 'deleted' in productCats) {
      parts.push(`product categories: ${productCats.deleted} deleted`);
    }
    const products = results.product;
    if (products && !('status' in products) && 'deleted' in products) {
      const img =
        products.imagesDeleted != null
          ? `, ${products.imagesDeleted} images deleted`
          : '';
      parts.push(`products: ${products.deleted} deleted${img}`);
    }
    const portfolioCats = results.portfolio_categories;
    if (
      portfolioCats &&
      !('status' in portfolioCats) &&
      'deleted' in portfolioCats
    ) {
      parts.push(`portfolio categories: ${portfolioCats.deleted} deleted`);
    }
    const portfolios = results.portfolio;
    if (portfolios && !('status' in portfolios) && 'deleted' in portfolios) {
      const img =
        portfolios.imagesDeleted != null
          ? `, ${portfolios.imagesDeleted} images deleted`
          : '';
      parts.push(`portfolios: ${portfolios.deleted} deleted${img}`);
    }
    const blogCats = results.blog_categories;
    if (blogCats && !('status' in blogCats) && 'deleted' in blogCats) {
      parts.push(`blog categories: ${blogCats.deleted} deleted`);
    }
    const blogs = results.blog;
    if (blogs && !('status' in blogs) && 'deleted' in blogs) {
      const img =
        blogs.imagesDeleted != null
          ? `, ${blogs.imagesDeleted} images deleted`
          : '';
      parts.push(`blogs: ${blogs.deleted} deleted${img}`);
    }
    const customerCats = results.customer_categories;
    if (customerCats && !('status' in customerCats) && 'deleted' in customerCats) {
      parts.push(`customer categories: ${customerCats.deleted} deleted`);
    }
    const customers = results.customer;
    if (customers && !('status' in customers) && 'deleted' in customers) {
      parts.push(`customers: ${customers.deleted} deleted`);
    }
    if (pending.length) {
      parts.push(`not implemented yet: ${pending.join(', ')}`);
    }

    const status =
      implemented.length === 0
        ? ('noop' as const)
        : pending.length > 0
          ? ('partial' as const)
          : ('ok' as const);

    return {
      businessId: business.id.toString(),
      entities: dto.entities,
      status,
      results,
      message:
        parts.length > 0
          ? `Data removed. ${parts.join('. ')}.`
          : 'No matching data to remove.',
    };
  }

  private async assertSlugAvailable(slug: string, excludeId?: bigint) {
    const existing = await this.prisma.business.findUnique({ where: { slug } });
    if (existing && existing.id !== excludeId) {
      throw new ConflictException('Business slug is already taken');
    }
  }

  private async assertOldBusinessIdAvailable(oldBusinessId: bigint, excludeId?: bigint) {
    const existing = await this.prisma.business.findFirst({
      where: { oldBusinessId },
      select: { id: true, name: true },
    });
    if (existing && existing.id !== excludeId) {
      throw new ConflictException(
        `Old business id ${oldBusinessId} is already linked to "${existing.name}"`,
      );
    }
  }

  private async validateCategoryIds(categoryIds: number[]) {
    const ids = [...new Set(categoryIds)].map((id) => BigInt(id));
    const count = await this.prisma.businessCategory.count({
      where: { id: { in: ids }, isActive: true },
    });
    if (count !== ids.length) {
      throw new BadRequestException('One or more categoryIds are invalid');
    }
  }

  private async createOwnerUser(
    tx: Prisma.TransactionClient,
    dto: Pick<
      CreateBusinessDto,
      'ownerFirstName' | 'ownerLastName' | 'ownerCellNumber' | 'ownerPassword'
    >,
  ) {
    const existing = await tx.user.findUnique({
      where: { cellNumber: dto.ownerCellNumber },
    });

    // Users can own multiple businesses. If the cell number already exists,
    // leave that user unchanged and only attach the new business as owner.
    if (existing) {
      if (!existing.isActive) {
        throw new BadRequestException('Owner user is inactive');
      }
      return existing;
    }

    const passwordHash = await bcrypt.hash(dto.ownerPassword, 10);

    return tx.user.create({
      data: {
        cellNumber: dto.ownerCellNumber,
        passwordHash,
        firstName: dto.ownerFirstName.trim(),
        lastName: dto.ownerLastName.trim(),
        cellVerifiedAt: new Date(),
      },
    });
  }

  private async findOwnerUser(ownerUserId: number) {
    const owner = await this.prisma.user.findUnique({
      where: { id: BigInt(ownerUserId) },
    });
    if (!owner || !owner.isActive) {
      throw new NotFoundException('Owner user not found');
    }
    return owner;
  }

  private async assignOwner(
    tx: Prisma.TransactionClient,
    businessId: bigint,
    ownerUserId: bigint,
    invitedBy: bigint,
  ) {
    const businessOwnerRole = await tx.role.findUnique({
      where: { slug: 'business_owner' },
    });
    if (!businessOwnerRole) {
      throw new Error('business_owner role is missing');
    }

    await tx.businessUser.upsert({
      where: {
        businessId_userId: { businessId, userId: ownerUserId },
      },
      create: {
        businessId,
        userId: ownerUserId,
        isOwner: true,
        invitedBy,
      },
      update: {
        isOwner: true,
        roleId: null,
        invitedBy,
      },
    });

    const hasRole = await tx.userRole.findUnique({
      where: {
        userId_roleId: {
          userId: ownerUserId,
          roleId: businessOwnerRole.id,
        },
      },
    });

    if (!hasRole) {
      await tx.userRole.create({
        data: { userId: ownerUserId, roleId: businessOwnerRole.id },
      });
    }
  }

  private serializeBusiness(
    business: {
      id: bigint;
      name: string;
      nameFa: string | null;
      about: string | null;
      slug: string;
      isActive: boolean;
      oldBusinessId: bigint | null;
      createdAt: Date;
      updatedAt: Date;
      categoryAssignments: {
        category: {
          id: bigint;
          name: string;
          slug: string;
          parentId: bigint | null;
        };
      }[];
      businessUsers: {
        user: {
          id: bigint;
          cellNumber: string;
          firstName: string | null;
          lastName: string | null;
          email: string | null;
        };
      }[];
      domains: {
        id: bigint;
        host: string;
        isPrimary: boolean;
        isVerified: boolean;
        sslEnabled: boolean;
      }[];
    },
  ) {
    const owner = business.businessUsers[0]?.user ?? null;

    return {
      id: business.id,
      name: business.name,
      nameFa: business.nameFa,
      about: business.about,
      slug: business.slug,
      isActive: business.isActive,
      oldBusinessId:
        business.oldBusinessId != null ? business.oldBusinessId.toString() : null,
      createdAt: business.createdAt,
      updatedAt: business.updatedAt,
      categories: business.categoryAssignments.map((a) => ({
        id: a.category.id,
        name: a.category.name,
        slug: a.category.slug,
        parentId: a.category.parentId,
      })),
      categoryIds: business.categoryAssignments.map((a) => a.category.id),
      owner: owner
        ? {
            id: owner.id,
            cellNumber: owner.cellNumber,
            firstName: owner.firstName,
            lastName: owner.lastName,
            email: owner.email,
          }
        : null,
      ownerUserId: owner?.id ?? null,
      domains: business.domains,
    };
  }

  private formatBusinessLabel(business: {
    name: string;
    nameFa: string | null;
    slug: string;
  }): string {
    if (business.nameFa && business.nameFa !== business.name) {
      return `${business.name} / ${business.nameFa}`;
    }
    return business.name;
  }
}