package com.drinkool.services;

import com.drinkool.InternalValue;
import com.drinkool.Role;
import com.drinkool.dtos.CreateShift;
import com.drinkool.dtos.RegisterShift;
import com.drinkool.entities.EateryEntity;
import com.drinkool.entities.ShiftEntity;
import com.drinkool.entities.ShiftRegistrationEntity;
import io.vertx.core.http.HttpServerRequest;
import jakarta.annotation.security.RolesAllowed;
import jakarta.enterprise.context.ApplicationScoped;
import jakarta.inject.Inject;
import jakarta.transaction.Transactional;
import java.util.List;
import java.util.UUID;
import java.util.stream.Collectors;
import org.eclipse.microprofile.graphql.*;

@GraphQLApi
@ApplicationScoped
public class ShiftService {

	@Inject
	HttpServerRequest request;

	// --- QUERIES ---

	@Query("allShifts")
	@Description("Lấy danh sách tất cả các loại ca trực")
	@RolesAllowed({ Role.Staff, Role.Manager })
	public List<ShiftEntity> getAllShifts() throws GraphQLException {
		String ownerId = request.getHeader(InternalValue.managerId);
		if (ownerId == null || ownerId.isEmpty()) {
			ownerId = request.getHeader(InternalValue.userId);
		}

		EateryEntity eatery = EateryEntity.findByOwnerId(ownerId);

		return ShiftEntity.list("eatery", eatery);
	}

	@Query("myRegistrations")
	@Description("Lấy danh sách ca trực mà nhân viên hiện tại đã đăng ký")
	@RolesAllowed(Role.Staff)
	public List<ShiftRegistrationEntity> getMyShifts() {
		String userId = request.getHeader(InternalValue.userId);
		return ShiftRegistrationEntity.list("staffId", UUID.fromString(userId));
	}

	@Query("allRegistrations")
	@Description("Manager xem toàn bộ danh sách đăng ký của tất cả nhân viên")
	@RolesAllowed(Role.Manager)
	public List<ShiftRegistrationEntity> getAllRegistrations() {
		return ShiftRegistrationEntity.listAll();
	}

	// --- MUTATIONS ---

	@Mutation("registerShift")
	@Description("Nhân viên đăng ký vào một ca trực cụ thể")
	@RolesAllowed(Role.Staff)
	@Transactional
	public ShiftRegistrationEntity registerShift(
		@Name("registration") RegisterShift registration
	) throws GraphQLException {
		String userIdStr = request.getHeader(InternalValue.userId);
		String managerIdStr = request.getHeader(InternalValue.managerId);
		UUID staffId = UUID.fromString(userIdStr);

		EateryEntity eatery = EateryEntity.findByOwnerId(managerIdStr);
		if (eatery == null) throw new GraphQLException("NotFoundEatery");

		ShiftEntity shift = ShiftEntity.find(
			"id = ?1 and eatery.id = ?2",
			registration.shiftId,
			eatery.id
		).firstResult();
		if (shift == null) throw new GraphQLException("NotFoundShift");

		List<ShiftRegistrationEntity> overlappingShifts =
			ShiftRegistrationEntity.findOverlappingShifts(staffId, shift);

		if (!overlappingShifts.isEmpty()) {
			String ids = overlappingShifts
				.stream()
				.map(reg -> reg.shift.id.toString())
				.distinct()
				.collect(Collectors.joining(", "));
			throw new GraphQLException("OverlappingShift: " + ids);
		}

		long currentStaffCount = ShiftRegistrationEntity.countByShift(shift.id);
		if (shift.maxStaff != null && currentStaffCount >= shift.maxStaff) {
			throw new GraphQLException("FulledShift");
		}

		ShiftRegistrationEntity record = new ShiftRegistrationEntity();
		record.staffId = staffId;
		record.shift = shift;
		record.persist();

		return record;
	}

	@Mutation("createShift")
	@Description("Quản lý tạo mới một loại ca trực")
	@RolesAllowed(Role.Manager)
	@Transactional
	public ShiftEntity createShift(@Name("shiftInput") CreateShift input)
		throws GraphQLException {
		String ownerId = request.getHeader(InternalValue.userId);

		EateryEntity eatery = EateryEntity.findByOwnerId(ownerId);
		if (eatery == null) return null;

		ShiftEntity shift = new ShiftEntity();
		shift.eatery = eatery;
		shift.name = input.name;
		shift.startTime = input.startTime;
		shift.endTime = input.endTime;
		shift.maxStaff = input.maxStaff;

		if (shift.endTime.isBefore(shift.startTime)) {
			throw new GraphQLException("InvalidEndTime");
		}

		shift.persist();
		return shift;
	}

	@Mutation("updateShift")
	@Description("Quản lý cập nhật thông tin ca trực")
	@RolesAllowed(Role.Manager)
	@Transactional
	public ShiftEntity updateShift(
		@Name("id") UUID id,
		@Name("shiftInput") CreateShift input
	) throws GraphQLException {
		ShiftEntity shift = ShiftEntity.findById(id);
		if (shift == null) throw new GraphQLException("NotFoundShift");

		String ownerId = request.getHeader(InternalValue.userId);
		if (
			!shift.eatery.ownerId.toString().equals(ownerId)
		) throw new GraphQLException("InvalidShiftId");

		shift.name = input.name;
		shift.startTime = input.startTime;
		shift.endTime = input.endTime;
		shift.maxStaff = input.maxStaff;

		if (shift.endTime.isBefore(shift.startTime)) {
			throw new GraphQLException("InvalidEndTime");
		}

		return shift;
	}

	@Mutation("deleteShift")
	@Description("Quản lý xóa một ca trực")
	@RolesAllowed(Role.Manager)
	@Transactional
	public boolean deleteShift(@Name("id") UUID id) throws GraphQLException {
		String ownerId = request.getHeader(InternalValue.userId);

		EateryEntity eatery = EateryEntity.findByOwnerId(ownerId);
		if (eatery == null) {
			throw new GraphQLException("NotFoundEatery");
		}

		ShiftEntity shift = ShiftEntity.find(
			"id = ?1 and eatery = ?2",
			id,
			eatery
		).firstResult();
		if (shift == null) {
			throw new GraphQLException("NotFoundShiftOrAccessDenied");
		}

		long count = ShiftRegistrationEntity.count("shift.id", id);
		if (count > 0) throw new GraphQLException(
			"CannotDeleteShiftWithRegistrations"
		);

		return ShiftEntity.deleteById(id);
	}

	@Mutation("cancelRegistration")
	@Description("Nhân viên hủy ca đã đăng ký")
	@RolesAllowed(Role.Staff)
	@Transactional
	public boolean cancelRegistration(@Name("registrationId") UUID id)
		throws GraphQLException {
		String userId = request.getHeader(InternalValue.userId);
		ShiftRegistrationEntity reg = ShiftRegistrationEntity.findById(id);

		if (reg == null) throw new GraphQLException("RegistrationNotFound");
		if (!reg.staffId.equals(UUID.fromString(userId))) {
			throw new GraphQLException("NotYourRegistration");
		}

		reg.delete();
		return true;
	}
}