import { prisma } from "@/lib/prisma";
import { ValidationError } from "@/modules/quote/types";

export type BusinessCustomerUserDto = {
  customer_id: string;
  business_customer_id: string;
  external_user_id: string;
  account: string;
  display_name: string | null;
  email: string | null;
  mobile: string | null;
  main_external_user_id: string | null;
  status: "active" | "inactive";
  created_at: string;
  updated_at: string;
};

export type ResolvedBusinessCustomerByAccount = {
  customer_id: string;
  business_customer_id: string;
  external_code: string | null;
  name: string;
  account: string;
};

function serializeUser(row: {
  customerId: string;
  businessCustomerId: string;
  externalUserId: string;
  account: string;
  displayName: string | null;
  email: string | null;
  mobile: string | null;
  mainExternalUserId: string | null;
  status: string;
  createdAt: Date;
  updatedAt: Date;
}): BusinessCustomerUserDto {
  return {
    customer_id: row.customerId,
    business_customer_id: row.businessCustomerId,
    external_user_id: row.externalUserId,
    account: row.account,
    display_name: row.displayName,
    email: row.email,
    mobile: row.mobile,
    main_external_user_id: row.mainExternalUserId,
    status: row.status === "active" ? "active" : "inactive",
    created_at: row.createdAt.toISOString(),
    updated_at: row.updatedAt.toISOString(),
  };
}

export async function listUsersByBusinessCustomer(
  customerId: string,
  businessCustomerId: string,
): Promise<BusinessCustomerUserDto[]> {
  const rows = await prisma.businessCustomerUser.findMany({
    where: {
      customerId,
      businessCustomerId,
      isDeleted: false,
    },
    orderBy: [{ status: "asc" }, { account: "asc" }],
  });
  return rows.map(serializeUser);
}

export async function listUsersByTenant(
  customerId: string,
  keyword?: string,
): Promise<
  Array<
    BusinessCustomerUserDto & {
      business_customer_code: string | null;
      business_customer_name: string;
    }
  >
> {
  const kw = keyword?.trim();
  const rows = await prisma.businessCustomerUser.findMany({
    where: {
      customerId,
      isDeleted: false,
      ...(kw
        ? {
            OR: [
              { account: { contains: kw } },
              { displayName: { contains: kw } },
              { businessCustomer: { externalCode: { contains: kw } } },
              { businessCustomer: { name: { contains: kw } } },
            ],
          }
        : {}),
    },
    include: {
      businessCustomer: {
        select: { externalCode: true, name: true },
      },
    },
    orderBy: [{ status: "asc" }, { account: "asc" }],
    take: 2000,
  });
  return rows.map((row) => ({
    ...serializeUser(row),
    business_customer_code: row.businessCustomer.externalCode,
    business_customer_name: row.businessCustomer.name,
  }));
}

/**
 * 按登录账号反查业务客户（仅 active）。
 * 账号大小写不敏感；同租户同账号多条时取最近更新。
 */
export async function resolveBusinessCustomerByAccount(
  customerId: string,
  accountRaw: string,
): Promise<ResolvedBusinessCustomerByAccount | null> {
  const account = accountRaw.trim();
  if (!customerId.trim() || !account) {
    return null;
  }
  const row = await prisma.businessCustomerUser.findFirst({
    where: {
      customerId,
      isDeleted: false,
      status: "active",
      account, // MySQL utf8mb4_unicode_ci 大小写不敏感
      businessCustomer: {
        isDeleted: false,
        status: "active",
      },
    },
    orderBy: { updatedAt: "desc" },
    include: {
      businessCustomer: {
        select: {
          businessCustomerId: true,
          externalCode: true,
          name: true,
        },
      },
    },
  });
  if (!row) {
    return null;
  }
  return {
    customer_id: row.customerId,
    business_customer_id: row.businessCustomer.businessCustomerId,
    external_code: row.businessCustomer.externalCode,
    name: row.businessCustomer.name,
    account: row.account,
  };
}

/** 无 BC 时用账号补全；账号无效则抛 ValidationError */
export async function resolveBusinessCustomerIdForQuote(input: {
  customerId: string;
  businessCustomerId?: string | null;
  businessUserAccount?: string | null;
}): Promise<string | undefined> {
  const explicit = input.businessCustomerId?.trim() || undefined;
  if (explicit) {
    return explicit;
  }
  const account = input.businessUserAccount?.trim() || "";
  if (!account) {
    return undefined;
  }
  const resolved = await resolveBusinessCustomerByAccount(
    input.customerId,
    account,
  );
  if (!resolved) {
    throw new ValidationError(
      `未识别到业务客户账号「${account}」，请确认账号已同步或显式传入业务客户`,
    );
  }
  return resolved.business_customer_id;
}

export type UpsertBusinessCustomerUserInput = {
  businessCustomerId: string;
  externalUserId: string;
  account: string;
  displayName?: string | null;
  email?: string | null;
  mobile?: string | null;
  mainExternalUserId?: string | null;
  status?: "active" | "inactive";
};

/**
 * 批量 upsert 业务客户登录账号（按 externalUserId 唯一）。
 * 若业务客户不存在则跳过该行并计入 skipped。
 */
export async function upsertBusinessCustomerUsers(
  customerId: string,
  rows: UpsertBusinessCustomerUserInput[],
): Promise<{ created: number; updated: number; skipped: number }> {
  let created = 0;
  let updated = 0;
  let skipped = 0;
  const tenantId = customerId.trim();
  if (!tenantId) {
    throw new ValidationError("租户标识不能为空");
  }

  for (const row of rows) {
    const businessCustomerId = row.businessCustomerId?.trim() || "";
    const externalUserId = row.externalUserId?.trim() || "";
    const account = row.account?.trim() || "";
    if (!businessCustomerId || !externalUserId || !account) {
      skipped += 1;
      continue;
    }

    const bc = await prisma.businessCustomer.findFirst({
      where: {
        customerId: tenantId,
        businessCustomerId,
        isDeleted: false,
      },
      select: { businessCustomerId: true },
    });
    if (!bc) {
      skipped += 1;
      continue;
    }

    const existing = await prisma.businessCustomerUser.findFirst({
      where: {
        customerId: tenantId,
        externalUserId,
      },
    });

    const data = {
      businessCustomerId,
      account,
      displayName: row.displayName?.trim() || null,
      email: row.email?.trim() || null,
      mobile: row.mobile?.trim() || null,
      mainExternalUserId: row.mainExternalUserId?.trim() || null,
      status: row.status === "inactive" ? "inactive" : "active",
      isDeleted: false,
    };

    if (existing) {
      await prisma.businessCustomerUser.update({
        where: { id: existing.id },
        data,
      });
      updated += 1;
    } else {
      await prisma.businessCustomerUser.create({
        data: {
          customerId: tenantId,
          externalUserId,
          ...data,
        },
      });
      created += 1;
    }
  }

  return { created, updated, skipped };
}