"""Logging configuration."""
import logging
import sys
from contextvars import ContextVar

request_id_var: ContextVar[str] = ContextVar("request_id", default="")


def configure_logging(log_level: str = "INFO") -> None:
    """Configure structured logging."""
    handler = logging.StreamHandler(sys.stdout)
    formatter = logging.Formatter(
        "%(asctime)s - %(name)s - %(levelname)s - [%(request_id)s] %(message)s"
    )
    handler.setFormatter(formatter)
    handler.addFilter(RequestIdFilter())

    root_logger = logging.getLogger()
    root_logger.setLevel(getattr(logging, log_level.upper(), logging.INFO))
    root_logger.handlers = []
    root_logger.addHandler(handler)

    # Reduce noise from third-party libraries
    logging.getLogger("sqlalchemy.engine").setLevel(logging.WARNING)
    logging.getLogger("uvicorn.access").setLevel(logging.WARNING)


class RequestIdFilter(logging.Filter):
    """Inject request_id into log records."""

    def filter(self, record: logging.LogRecord) -> bool:
        record.request_id = request_id_var.get()  # type: ignore[attr-defined]
        return True


def get_logger(name: str) -> logging.Logger:
    """Get a logger with request_id filter."""
    logger = logging.getLogger(name)
    logger.addFilter(RequestIdFilter())
    return logger