// /components/contactInquiries/contactInquiryService.js

const ContactInquiry = require('./contactInquiryModel');
const Course = require('../courses/courseModel');
const AppError = require('../../utils/AppError');
const { parsePaginationAndSort, buildFilterQuery, calculateMeta } = require('../../utils/pagination');

const normalizePhone = (value) => {
  if (!value) return undefined;
  return String(value).replace(/[\s\-()]/g, '').trim();
};

const createInquiry = async (data) => {
  const preferredContactMethods = Array.isArray(data.preferredContactMethods)
    ? [...new Set(data.preferredContactMethods)]
    : [];

  if (!preferredContactMethods.length) {
    throw new AppError('VALIDATION_FAILED', {
      preferredContactMethods: 'At least one preferred contact method is required'
    }, 'حداقل یک روش تماس را انتخاب کنید.');
  }

  const phoneNumber = normalizePhone(data.phoneNumber || data.phone);
  const email = data.email ? String(data.email).trim().toLowerCase() : undefined;

  if (!phoneNumber && !email) {
    throw new AppError('VALIDATION_FAILED', {
      contact: 'Phone number or email is required'
    }, 'شماره تلفن یا ایمیل الزامی است.');
  }

  const courseIds = Array.isArray(data.courses)
    ? [...new Set(data.courses.filter(Boolean).map(String))]
    : [];

  if (courseIds.length) {
    const foundCount = await Course.countDocuments({
      _id: { $in: courseIds },
      showOnFrontend: { $ne: false }
    });
    if (foundCount !== courseIds.length) {
      throw new AppError('COURSE_NOT_FOUND', null, 'یکی از دوره‌های انتخاب‌شده یافت نشد.');
    }
  }

  const inquiry = await ContactInquiry.create({
    name: data.name || data.firstName,
    surname: data.surname || data.lastName,
    nationalIdCode: data.nationalIdCode || data.nationalId || undefined,
    phoneNumber,
    email,
    message: data.message || undefined,
    preferredContactMethods,
    courses: courseIds
  });

  return inquiry.populate('courses', 'title type price');
};

const getAllInquiries = async (queryParams) => {
  const { page, limit, skip, sort } = parsePaginationAndSort(queryParams, 'createdAt', 'desc');
  const filter = buildFilterQuery(
    queryParams,
    ['name', 'surname', 'nationalIdCode', 'phoneNumber', 'email', 'notes', 'message'],
    ['page', 'limit', 'sortBy', 'sortOrder', 'q', 'lang', 'course', 'courseId', 'courses']
  );

  const courseFilter = queryParams.course || queryParams.courseId || queryParams.courses;
  if (courseFilter) {
    const ids = String(courseFilter).split(',').map((id) => id.trim()).filter(Boolean);
    if (ids.length === 1) filter.courses = ids[0];
    else if (ids.length > 1) filter.courses = { $in: ids };
  }

  const [data, totalCount] = await Promise.all([
    ContactInquiry.find(filter)
      .populate('courses', 'title type price')
      .sort(sort)
      .skip(skip)
      .limit(limit),
    ContactInquiry.countDocuments(filter)
  ]);

  return { data, meta: calculateMeta(totalCount, page, limit) };
};

const getInquiryById = async (id) => {
  const inquiry = await ContactInquiry.findById(id).populate('courses', 'title type price');
  if (!inquiry) {
    throw new AppError('NOT_FOUND', null, 'درخواست تماس یافت نشد.');
  }
  return inquiry;
};

const updateInquiry = async (id, updateData) => {
  const inquiry = await ContactInquiry.findById(id);
  if (!inquiry) {
    throw new AppError('NOT_FOUND', null, 'درخواست تماس یافت نشد.');
  }

  if (updateData.status !== undefined) {
    if (!ContactInquiry.CONTACT_STATUSES.includes(updateData.status)) {
      throw new AppError('VALIDATION_FAILED', { status: 'Invalid status' }, 'وضعیت نامعتبر است.');
    }
    inquiry.status = updateData.status;
  }

  if (updateData.notes !== undefined) {
    inquiry.notes = String(updateData.notes).slice(0, 5000);
  }

  await inquiry.save();
  return getInquiryById(id);
};

module.exports = {
  createInquiry,
  getAllInquiries,
  getInquiryById,
  updateInquiry
};