from __future__ import annotations

import json
from datetime import datetime
from typing import Any, Dict, Optional


class StructuredLogger:
    def __init__(self):
        pass

    def log(self, level: str, event: str, trace_id: str, payload: Optional[Dict[str, Any]] = None, error_code: Optional[str] = None) -> None:
        print(json.dumps({
            "trace_id": trace_id,
            "level": level,
            "event": event,
            "error_code": error_code,
            "payload": payload or {},
            "created_at": datetime.now().isoformat(),
        }, ensure_ascii=False))


_GLOBAL_STRUCTURED_LOGGER: Optional[StructuredLogger] = None


def get_structured_logger() -> StructuredLogger:
    global _GLOBAL_STRUCTURED_LOGGER
    if _GLOBAL_STRUCTURED_LOGGER is None:
        _GLOBAL_STRUCTURED_LOGGER = StructuredLogger()
    return _GLOBAL_STRUCTURED_LOGGER