import asyncio
from datetime import datetime,timezone

#from sqlalchemy import create_engine #Не async
from sqlalchemy.orm import DeclarativeBase, sessionmaker
from sqlalchemy.ext.asyncio import AsyncSession, create_async_engine
from sqlalchemy import Column, Integer, String, Boolean, select,func, DateTime

from pathlib import Path
db_folder = Path(__file__).parent / "DB"
db_folder.mkdir(parents=True, exist_ok=True)
db_path = db_folder / "example.db"
async_engine = create_async_engine(f"sqlite+aiosqlite:///{db_path}", echo=True)
#sqlite+aiosqlite — тип БД + async-драйвер ///example.db — путь к файлу (три слэша, если путь относительный; четыре, если абсолютный
#async_engine = create_async_engine( "postgresql+asyncpg://user:pass@host:5432/mydb", echo=True) #Можно указать Pgpool-II для psql или proxysql для mysql mariadb

from passlib.context import CryptContext
#Hash password
pwd_context = CryptContext(schemes=["bcrypt"], deprecated="auto")
def hash_password(password: str) -> str:
    return pwd_context.hash(password)
def verify_password(plain_password: str, hashed_password: str) -> bool:
    return pwd_context.verify(plain_password, hashed_password)

class Base(DeclarativeBase):
    pass

AsyncSessionLocal = sessionmaker(async_engine,class_=AsyncSession, expire_on_commit=False)

class User(Base):
    __tablename__ = "users"

    id = Column(Integer, primary_key=True, index=True)
    email = Column(String(254), unique=True, nullable=False)
    description = Column(String, nullable=False)
    activated = Column(Boolean, default=False)
    password = Column(String, nullable=False)
    created_at = Column(DateTime(timezone=True), server_default=func.now())
    updated_at = Column(DateTime(timezone=True), onupdate=func.now())
    last_login = Column(DateTime(timezone=True))

async def init_db():
    async with async_engine.begin() as conn:
        await conn.run_sync(Base.metadata.create_all)
async def create_user(user_info):
    async with AsyncSessionLocal() as session:
        new_user = User(email=user_info.email, description=user_info.description, activated=user_info.activated, password=hash_password(user_info.password))
        session.add(new_user)
        await session.commit()
        await session.refresh(new_user)
async def get_user_by_email(email):
    async with AsyncSessionLocal() as session:
        result = await session.execute(select(User).where(User.email==email))
        user = result.scalar_one_or_none()
        return user
async def get_all_rows():
    async with AsyncSessionLocal() as session:
        result = await session.execute(select(User))
        users = result.scalars().all()
        return users
async def update_user(user_info):
    async with AsyncSessionLocal() as session:
        result = await session.execute(select(User).where(User.id==user_info.id))
        user = result.scalar_one_or_none()
        if user:
            user.email = user_info.email
            user.description = user_info.description
            user.activated = user_info.activated
            user.password = hash_password(user_info.password)
            await session.commit()
async def delete_user(email):
    async with AsyncSessionLocal() as session:
        result = await session.execute(select(User).where(User.email==email))
        user = result.scalar_one_or_none()
        if user:
            await session.delete(user)
            await session.commit()
async def login_user(user_info):
    async with AsyncSessionLocal() as session:
        result = await session.execute(select(User).where(User.email == user_info.email))
        user = result.scalar_one_or_none()
        if user and verify_password(user_info.password, user.password):
            user.last_login=datetime.now(timezone.utc)
            await session.commit()
            return user
        return None
async def reset_user(user_info):
    async with AsyncSessionLocal() as session:
        result = await session.execute(select(User).where(User.email == user_info.email))
        user = result.scalar_one_or_none()
        if user:
            user.password = hash_password(user_info.new_password)
            await session.commit()
            return user
        return None
async def main():
    await init_db()