package com.example.nto.service.impl;

import com.example.nto.entity.Booking;
import com.example.nto.entity.Employee;
import com.example.nto.entity.Place;
import com.example.nto.repository.BookingRepository;
import com.example.nto.repository.EmployeeRepository;
import com.example.nto.repository.PlaceRepository;
import com.example.nto.service.BookingService;
import org.springframework.stereotype.Service;
import org.springframework.transaction.annotation.Transactional;

import java.time.LocalDate;
import java.util.*;
import java.util.stream.Collectors;

@Service
public class BookingServiceImpl implements BookingService {

    private final BookingRepository bookingRepository;
    private final PlaceRepository placeRepository;
    private final EmployeeRepository employeeRepository;

    public BookingServiceImpl(BookingRepository bookingRepository,
                              PlaceRepository placeRepository,
                              EmployeeRepository employeeRepository) {
        this.bookingRepository = bookingRepository;
        this.placeRepository = placeRepository;
        this.employeeRepository = employeeRepository;
    }

    @Override
    public Map<LocalDate, List<Place>> getAvailablePlacesForRange(LocalDate start, int days) {
        Map<LocalDate, List<Place>> result = new LinkedHashMap<>();
        List<Place> allPlaces = placeRepository.findAll();

        for (int i = 0; i < days; i++) {
            LocalDate date = start.plusDays(i);
            List<Booking> booked = bookingRepository.findByDate(date);
            Set<Long> bookedIds = booked.stream()
                    .map(b -> b.getPlace().getId())
                    .collect(Collectors.toSet());

            List<Place> free = allPlaces.stream()
                    .filter(p -> !bookedIds.contains(p.getId()))
                    .collect(Collectors.toList());

            result.put(date, free);
        }
        return result;
    }

    @Override
    @Transactional
    public void createBooking(String code, LocalDate date, Long placeId) {
        // Проверка существования сотрудника
        Employee employee = employeeRepository.findByCode(code)
                .orElseThrow(() -> new IllegalArgumentException("Employee not found"));

        // Проверка существования места
        Place place = placeRepository.findById(placeId)
                .orElseThrow(() -> new IllegalArgumentException("Place not found"));

        // Проверка, что место уже не забронировано на эту дату
        boolean alreadyBooked = bookingRepository.findByPlaceAndDate(place, date).isPresent();
        if (alreadyBooked) {
            throw new IllegalStateException("Place already booked");
        }

        // Создание и сохранение нового бронирования
        Booking booking = new Booking(date, place, employee);
        bookingRepository.save(booking);
    }
}