from datetime import datetime

from sqlalchemy import Column, Integer, DateTime, VARCHAR, DATE, TEXT, ForeignKey, create_engine
from sqlalchemy.ext.declarative import declarative_base
from sqlalchemy.orm import relationship, sessionmaker, Session

__factory = None
base = declarative_base()


class BaseModel(base):
    __abstract__ = True

    id = Column(Integer, primary_key=True, autoincrement=True)


class Role(BaseModel):
    __tablename__ = 'roles'

    title = Column(VARCHAR(50), nullable=False)


class Gender(BaseModel):
    __tablename__ = 'genders'

    title = Column(VARCHAR(50), nullable=False)


class Country(BaseModel):
    __tablename__ = 'countries'

    title = Column(VARCHAR(250), nullable=False)
    english_title = Column(VARCHAR(250), nullable=False)
    code_alpha = Column(VARCHAR(10), nullable=False)
    code_digits = Column(VARCHAR(10), nullable=False)

    cities = relationship('City', backref='country')


class City(BaseModel):
    __tablename__ = 'cities'

    title = Column(VARCHAR(250), nullable=False)

    country_id = Column(Integer, ForeignKey('countries.id'), nullable=False)

    country = relationship('Country', backref='cities')

    events = relationship('Event', backref='city')


class User(BaseModel):
    __tablename__ = 'users'

    last_name = Column(VARCHAR(50), nullable=False)
    first_name = Column(VARCHAR(50), nullable=False)
    patronym = Column(VARCHAR(50))
    email = Column(VARCHAR(150), nullable=False)
    birthday = Column(DATE, nullable=False)
    phone = Column(VARCHAR(50), nullable=False)
    password = Column(TEXT, nullable=False)
    photo = Column(TEXT, nullable=False)

    gender_id = Column(Integer, ForeignKey('genders.id'), nullable=False)
    role_id = Column(Integer, ForeignKey('roles.id'), nullable=False)
    country_id = Column(Integer, ForeignKey('countries.id'), nullable=False)

    moders = relationship('Moder', backref='user')


class Direction(BaseModel):
    __tablename__ = 'directions'

    title = Column(VARCHAR(150), nullable=False)

    moders = relationship('Moder', backref='direction')


class Event(BaseModel):
    __tablename__ = 'events'

    title = Column(VARCHAR(250), nullable=False)
    date = Column(DATE, nullable=False)
    days_count = Column(Integer, nullable=False)

    city_id = Column(Integer, ForeignKey('cities.id'), nullable=False)

    city = relationship('City', backref='events')

    moders = relationship('Moder', backref='event')


class Moder(BaseModel):
    __tablename__ = 'moders'

    user_id = Column(Integer, ForeignKey('users.id'), nullable=False)
    event_id = Column(Integer, ForeignKey('events.id'), nullable=False)
    direction_id = Column(Integer, ForeignKey('directions.id'), nullable=False)

    user = relationship('User', backref='moders')
    event = relationship('Event', backref='moders')
    direction = relationship('Direction', backref='moders')


def init_db():
    global __factory

    eng = create_engine('postgresql+pg8000://postgres:2509@localhost:5432/demo_1')
    __factory = sessionmaker(bind=eng)

    base.metadata.create_all(eng)


def connect() -> Session:
    global __factory
    return __factory()