from sqlalchemy import Column, Integer, String, ForeignKey, DateTime
from sqlalchemy.orm import relationship
from datetime import datetime, timezone
from .room_management import Room, Base  # 假设room_management.py在同一包内，或根据实际情况调整导入路径

# 预订模型
class Booking(Base):
    __tablename__ = 'bookings'  # 注意双下划线的正确使用
    id = Column(Integer, primary_key=True)
    room_id = Column(Integer, ForeignKey('rooms.id'), nullable=False)
    guest_name = Column(String, nullable=False)
    start_date = Column(DateTime, nullable=False, default=lambda: datetime.now(timezone.utc))  # 使用时区感知的默认值
    end_date = Column(DateTime, nullable=False)
    room = relationship("Room", back_populates="bookings")

    def __repr__(self):
        return f"Booking(id={self.id}, room={self.room.room_number}, guest='{self.guest_name}', start_date={self.start_date}, end_date={self.end_date})"

# 初始化Room模型与Booking之间的关系
Room.bookings = relationship("Booking", order_by=Booking.id, back_populates="room")

def make_booking(room_number, guest_name, start_date_str, end_date_str):
    """创建预订"""
    from dateutil.parser import parse
    try:
        start_date = parse(start_date_str).replace(tzinfo=None)
        end_date = parse(end_date_str).replace(tzinfo=None)
        room = session.query(Room).filter_by(room_number=room_number, status='available').first()
        if not room:
            return "该房间不可用或不存在。"
        new_booking = Booking(guest_name=guest_name, start_date=start_date, end_date=end_date, room=room)
        room.status = 'occupied'
        session.add(new_booking)
        session.commit()
        return f"{guest_name} 的预订成功，房间号：{room_number}，时间：{start_date} 至 {end_date}"
    except Exception as e:
        return str(e)

def cancel_booking(booking_id):
    """取消预订"""
    booking = session.query(Booking).get(booking_id)
    if not booking:
        return "预订记录不存在。"
    room = booking.room
    room.status = 'available'
    session.delete(booking)
    session.commit()
    return f"预订ID为{booking_id}的预订已取消。"

def get_bookings_by_guest(guest_name=None):
    """按客人姓名获取预订记录"""
    query = session.query(Booking)
    if guest_name:
        query = query.filter_by(guest_name=guest_name)
    return query.all()

def get_bookings_by_room(room_number):
    """按房间号获取预订记录"""
    room = session.query(Room).filter_by(room_number=room_number).first()
    if not room:
        return []
    return room.bookings