import json
import logging
from datetime import datetime, timezone


class JsonFormatter(logging.Formatter):
    def format(self, record: logging.LogRecord) -> str:
        payload: dict[str, object] = {
            "timestamp": datetime.now(timezone.utc).isoformat(),
            "level": record.levelname,
            "logger": record.name,
            "message": record.getMessage(),
        }
        for key in ("monitor_id", "target", "outcome", "latency_ms", "http_status"):
            value = getattr(record, key, None)
            if value is not None:
                payload[key] = value
        return json.dumps(payload, separators=(",", ":"), default=str)


def configure_logging(level: str) -> None:
    handler = logging.StreamHandler()
    handler.setFormatter(JsonFormatter())
    root = logging.getLogger()
    root.handlers = [handler]
    root.setLevel(level.upper())