"""JSON structured logging on stdout."""

from __future__ import annotations

import logging
import sys

from pythonjsonlogger import jsonlogger


def configure_logging(level: str = "INFO") -> None:
    """Replace the root handler with a single JSON stdout handler.

    Fields emitted: ts, level, name, msg, plus any extras passed via `logger.X(..., extra={...})`.
    """
    root = logging.getLogger()
    root.setLevel(level.upper())

    # Drop any pre-existing handlers (uvicorn/gunicorn add their own).
    for h in list(root.handlers):
        root.removeHandler(h)

    handler = logging.StreamHandler(sys.stdout)
    formatter = jsonlogger.JsonFormatter(
        fmt="%(asctime)s %(levelname)s %(name)s %(message)s",
        rename_fields={"asctime": "ts", "levelname": "level", "name": "logger"},
        json_ensure_ascii=False,
    )
    handler.setFormatter(formatter)
    root.addHandler(handler)

    # Tame the noisy third parties unless explicitly debugging.
    if level.upper() != "DEBUG":
        logging.getLogger("werkzeug").setLevel(logging.WARNING)