"""Shared asyncpg connection pool."""

from __future__ import annotations

import logging
from typing import Optional

import asyncpg

logger = logging.getLogger(__name__)

_pool: Optional[asyncpg.Pool] = None


async def init_pool(
    host: str,
    port: int,
    dbname: str,
    user: str,
    password: str,
    min_size: int = 1,
    max_size: int = 5,
) -> asyncpg.Pool:
    """Create the shared connection pool. Call once during app startup."""
    global _pool
    _pool = await asyncpg.create_pool(
        host=host,
        port=port,
        database=dbname,
        user=user,
        password=password,
        min_size=min_size,
        max_size=max_size,
    )
    logger.info("Database pool initialized (%s:%d/%s)", host, port, dbname)
    return _pool


async def get_pool() -> asyncpg.Pool:
    """Return the shared pool. Raises if not yet initialized."""
    if _pool is None:
        raise RuntimeError("Database pool not initialized — call init_pool() first")
    return _pool


async def close_pool() -> None:
    """Close the shared pool. Call during app shutdown."""
    global _pool
    if _pool is not None:
        await _pool.close()
        _pool = None
        logger.info("Database pool closed")