from dataclasses import dataclass
from datetime import datetime
from abc import ABC, abstractmethod

# Domain command + IDs used at the boundary of the application layer
@dataclass
class BookingId:
    value: str

@dataclass
class CreateBookingCommand:
    user_id: str
    departure: datetime
    origin: str
    destination: str

# Application service interface
class BookingApplicationService(ABC):
    @abstractmethod
    def create_booking(self, command: CreateBookingCommand) -> "Booking":
        pass

    @abstractmethod
    def get_booking(self, booking_id: BookingId) -> "Booking | None":
        pass

class BookingApplicationServiceImpl(BookingApplicationService):
    def __init__(
        self,
        bookings: "BookingRepository",
        payments: "PaymentAdapter",
    ):
        self._bookings = bookings
        self._payments = payments

    def create_booking(self, command: CreateBookingCommand) -> "Booking":
        # Validation & business rules
        # (no HTTP, no SDK types)
        self._validate_command(command)

        provisional = Booking.provisional(
            user_id=command.user_id,
            departure=command.departure,
            origin=command.origin,
            destination=command.destination,
        )

        # Orchestration via adapters/repositories
        payment_result = self._payments.charge(
            PaymentRequest.for_booking(provisional),
        )

        confirmed = provisional.confirm(payment_result)
        self._bookings.save(confirmed)
        return confirmed

    def get_booking(self, booking_id: BookingId) -> "Booking | None":
        return self._bookings.find_by_id(booking_id)

    def _validate_command(self, command: CreateBookingCommand) -> None:
        # Pure validation; raise domain-level errors only
        pass