import os
from flask import Flask, g
from sqlalchemy.ext.asyncio import create_async_engine, AsyncSession
from sqlalchemy.orm import sessionmaker
from motor.motor_asyncio import AsyncIOMotorClient
from sqlalchemy import Column, String, Numeric, DateTime, Boolean, ForeignKey, Integer
from sqlalchemy.orm import declarative_base, relationship
from datetime import datetime
import uuid
import asyncio

# Инициализация Flask
app = Flask(__name__)

# Настройки PostgreSQL из переменных окружения
POSTGRES_DSN = os.getenv("POSTGRES_URL")

# Создание движка для PostgreSQL
postgres_engine = create_async_engine(POSTGRES_DSN, echo=False)
AsyncSessionLocal = sessionmaker(bind=postgres_engine, class_=AsyncSession, expire_on_commit=False)

# Настройки MongoDB из переменных окружения
MONGO_URI = os.getenv("MONGO_URL")
DATABASE_NAME = os.getenv("DB_NAME")

# Создание клиента MongoDB
mongo_client = AsyncIOMotorClient(MONGO_URI)
mongo_db = mongo_client[DATABASE_NAME]

# SQLAlchemy Base
Base = declarative_base()

def generate_uuid():
    return str(uuid.uuid4())

"""Пользователи"""
class User(Base):
    __tablename__ = 'users'

    id = Column(String, primary_key=True, default=generate_uuid)
    telegram_id = Column(Integer, unique=True, nullable=False)
    username = Column(String)
    balance = Column(Numeric(10, 2), default=0.0)
    created_at = Column(DateTime, default=datetime.utcnow)
    updated_at = Column(DateTime, default=datetime.utcnow, onupdate=datetime.utcnow)

    subscriptions = relationship("Subscription", back_populates="user")
    transactions = relationship("Transaction", back_populates="user")
    admins = relationship("Administrators", back_populates="user")

"""Подписки"""
class Subscription(Base):
    __tablename__ = 'subscriptions'

    id = Column(String, primary_key=True, default=generate_uuid)
    user_id = Column(String, ForeignKey('users.id'))
    vpn_server_id = Column(String)
    plan = Column(String)
    expiry_date = Column(DateTime)
    created_at = Column(DateTime, default=datetime.utcnow)
    updated_at = Column(DateTime, default=datetime.utcnow, onupdate=datetime.utcnow)

    user = relationship("User", back_populates="subscriptions")

"""Транзакции"""
class Transaction(Base):
    __tablename__ = 'transactions'

    id = Column(String, primary_key=True, default=generate_uuid)
    user_id = Column(String, ForeignKey('users.id'))
    amount = Column(Numeric(10, 2))
    transaction_type = Column(String)
    created_at = Column(DateTime, default=datetime.utcnow)

    user = relationship("User", back_populates="transactions")

"""Администраторы"""
class Administrators(Base):
    __tablename__ = 'admins'

    id = Column(String, primary_key=True, default=generate_uuid)
    user_id = Column(String, ForeignKey('users.id'))

    user = relationship("User", back_populates="admins")

@app.before_first_request
async def init_databases():
    """
    Инициализация подключений к PostgreSQL и MongoDB перед первым запросом.
    """
    try:
        # Инициализация PostgreSQL
        async with postgres_engine.begin() as conn:
            await conn.run_sync(Base.metadata.create_all)
            print("PostgreSQL connected.")

        # Проверка подключения к MongoDB
        await mongo_client.admin.command("ping")
        print("MongoDB connected.")
    except Exception as e:
        print(f"Database initialization failed: {e}")

@app.teardown_appcontext
def close_connections(exception=None):
    """
    Закрытие соединений с базами данных после окончания работы приложения.
    """
    asyncio.run(postgres_engine.dispose())
    mongo_client.close()
    print("Database connections closed.")

@app.route("/postgres_session")
async def get_postgres_session():
    """
    Пример использования сессии PostgreSQL в маршруте Flask.
    """
    try:
        async with AsyncSessionLocal() as session:
            # Здесь можно выполнить запросы к базе данных PostgreSQL
            result = await session.execute("SELECT 1")
            return {"postgres_result": result.scalar()}
    except Exception as e:
        return {"error": str(e)}, 500

@app.route("/mongo_status")
async def get_mongo_status():
    """
    Пример проверки MongoDB в маршруте Flask.
    """
    try:
        await mongo_client.admin.command("ping")
        return {"mongo_status": "connected"}
    except Exception as e:
        return {"error": str(e)}, 500

if __name__ == "__main__":
    app.run(debug=True)