# Database configuration package
from pydantic import BaseModel
import os
import urllib.parse

class Settings(BaseModel):
    DB_HOST: str = os.getenv("DB_HOST", "postgres")
    DB_PORT: int = int(os.getenv("DB_PORT", "5432"))
    DB_USER: str = os.getenv("DB_USER", "postgres")
    DB_PASS: str = os.getenv("DB_PASS", "")
    DB_NAME: str = os.getenv("DB_NAME", "profi")

    @property
    def DATABASE_URL_syncpg(self) -> str:
        pwd = urllib.parse.quote_plus(str(self.DB_PASS))
        return f"postgresql+pg8000://{self.DB_USER}:{pwd}@{self.DB_HOST}:{self.DB_PORT}/{self.DB_NAME}"

    @property
    def PG8000_CONNECT_ARGS(self) -> dict:
        """connect_args для pg8000 — отключаем SSL (сервер его не поддерживает)."""
        return {"ssl_context": None}


def make_engine():
    """Создаёт SQLAlchemy engine с правильными параметрами для pg8000."""
    from sqlalchemy import create_engine
    s = Settings()
    return create_engine(
        s.DATABASE_URL_syncpg,
        connect_args=s.PG8000_CONNECT_ARGS,
        future=True,
        pool_pre_ping=True,
        pool_size=5,
        max_overflow=5,
        pool_timeout=30,
        pool_recycle=1800,
    )


def wait_for_db(retries: int = 15, delay: float = 2.0) -> None:
    """Ждёт, пока PostgreSQL станет доступен. Вызывается при старте приложения."""
    import time
    import logging
    from sqlalchemy import text

    logger = logging.getLogger("bd")
    engine = make_engine()
    for attempt in range(1, retries + 1):
        try:
            with engine.connect() as conn:
                conn.execute(text("SELECT 1"))
            logger.info("PostgreSQL is ready.")
            return
        except Exception as exc:
            logger.warning("DB not ready (attempt %d/%d): %s", attempt, retries, exc)
            if attempt < retries:
                time.sleep(delay)
    raise RuntimeError("PostgreSQL did not become ready in time.")

# ── Singleton engine + session factory (один движок на весь процесс) ───────
_engine = None
_SessionFactory = None


def get_engine():
    global _engine
    if _engine is None:
        _engine = make_engine()
    return _engine


def get_session():
    global _SessionFactory
    if _SessionFactory is None:
        from sqlalchemy.orm import sessionmaker
        _SessionFactory = sessionmaker(bind=get_engine(), future=True)
    return _SessionFactory