import os
import asyncio
import sqlalchemy
from sqlalchemy.ext.asyncio import create_async_engine, AsyncSession, async_sessionmaker
from sqlalchemy.orm import DeclarativeBase

DATABASE_URL = os.getenv("DATABASE_URL", "postgresql+asyncpg://postgres:postgres@localhost:5432/news")
REDIS_URL = os.getenv("REDIS_URL", "redis://localhost:6379/0")

engine = create_async_engine(DATABASE_URL, pool_size=10, max_overflow=20, echo=False)
AsyncSessionLocal = async_sessionmaker(engine, expire_on_commit=False)


class Base(DeclarativeBase):
    pass


async def get_db():
    async with AsyncSessionLocal() as session:
        yield session


async def wait_for_db():
    for attempt in range(30):
        try:
            async with engine.connect() as conn:
                await conn.execute(sqlalchemy.text("SELECT 1"))
            return
        except Exception:
            if attempt == 29:
                raise
            await asyncio.sleep(2)


import redis.asyncio as aioredis

_redis: aioredis.Redis | None = None


async def get_redis() -> aioredis.Redis:
    global _redis
    if _redis is None:
        _redis = aioredis.from_url(REDIS_URL, encoding="utf-8", decode_responses=True)
    return _redis