import { BadRequestException, Injectable, NotFoundException } from '@nestjs/common';
import { CreatePagerDto } from './dto/create-pager.dto';
import { User } from '../users/entities/user.entity';
import { EntityManager } from '@mikro-orm/postgresql';
import { Restaurant } from '../restaurants/entities/restaurant.entity';
import { Pager } from './entities/pager.entity';
import { PagerStatus } from './interface/pager';
import { ulid } from 'ulid';
import { Admin } from '../admin/entities/admin.entity';

@Injectable()
export class PagerService {
  constructor(private readonly em: EntityManager) {}

  async create(createPagerDto: CreatePagerDto, params: { restId?: string; userId?: string; slug: string }) {
    const { restId, userId, slug } = params;
    let restaurant: Restaurant | null = null;
    let user: User | null = null;
    if (!restId && !userId && !slug) {
      throw new BadRequestException('Invalid parameters');
    }
    if (restId) {
      restaurant = await this.em.findOne(Restaurant, { id: restId });
      if (!restaurant) {
        throw new NotFoundException('Restaurant not found');
      }
    }
    if (userId) {
      user = await this.em.findOne(User, { id: userId });
      if (!user) {
        throw new NotFoundException('User not found');
      }
    }
    if (!restaurant && slug) {
      restaurant = await this.em.findOne(Restaurant, { slug });
      if (!restaurant) {
        throw new NotFoundException('Restaurant not found');
      }
    }

    const pager = this.em.create(Pager, {
      ...createPagerDto,
      restaurant: restaurant!,
      user,
      cookieId: ulid().toString(),
      status: PagerStatus.Pending,
    });

    await this.em.persistAndFlush(pager);
    return pager;
  }

  async findAll(cookieId: string) {
    const pagers = await this.em.find(Pager, { cookieId }, { populate: ['user'] });
    return pagers;
  }

  async findAllByRestaurantId(restId: string) {
    const pagers = await this.em.find(Pager, { restaurant: { id: restId } }, { populate: ['user'] });
    return pagers;
  }

  async updateStatus(pagerId: string, restId: string, staffId: string, status: PagerStatus) {
    const pager = await this.em.findOne(Pager, { id: pagerId, restaurant: { id: restId } });
    if (!pager) {
      throw new NotFoundException('Pager not found *');
    }
    const staff = await this.em.findOne(Admin, { id: staffId });
    if (!staff) {
      throw new NotFoundException('Staff not found');
    }
    pager.status = status;
    if (status === PagerStatus.Acknowledged) {
      pager.staff = staff;
    }
    await this.em.persistAndFlush(pager);
    return pager;
  }
}