"""
Database configuration and session management.
Handles both synchronous and asynchronous database connections.
"""

from typing import Generator, AsyncGenerator
from sqlalchemy import create_engine
from sqlalchemy.ext.asyncio import AsyncSession, create_async_engine, async_sessionmaker
from sqlalchemy.ext.declarative import declarative_base
from sqlalchemy.orm import Session, sessionmaker

from config import settings

# Base class for models
Base = declarative_base()

# Synchronous database configuration
engine = create_engine(
    settings.DATABASE_URL,
    echo=False,
    pool_pre_ping=True,
    pool_recycle=3600,
    pool_size=10,
    max_overflow=20
)

SessionLocal = sessionmaker(
    autocommit=False,
    autoflush=False,
    bind=engine
)

# Asynchronous database configuration
async_db_url = f"mysql+asyncmy://{settings.DB_USER}:{settings.DB_PASSWORD}@{settings.DB_HOST}/{settings.DB_NAME}"

async_engine = create_async_engine(
    async_db_url,
    echo=False,
    pool_pre_ping=True,
    pool_recycle=3600,
    pool_size=10,
    max_overflow=20
)

AsyncSessionLocal = async_sessionmaker(
    bind=async_engine,
    expire_on_commit=False,
    class_=AsyncSession
)


def get_db() -> Generator[Session, None, None]:
    """Dependency for getting synchronous database session."""
    db = SessionLocal()
    try:
        yield db
    finally:
        db.close()


async def get_async_db() -> AsyncGenerator[AsyncSession, None]:
    """Dependency for getting asynchronous database session."""
    async with AsyncSessionLocal() as session:
        yield session