from typing import Any

def extract_token_usage(message: Any) -> dict[str, int]:
    usage = getattr(message, "usage_metadata", None)
    if isinstance(usage, dict):
        return {
            "input_tokens": int(usage.get("input_tokens", 0) or 0),
            "output_tokens": int(usage.get("output_tokens", 0) or 0),
            "total_tokens": int(usage.get("total_tokens", 0) or 0),
        }

    response_metadata = getattr(message, "response_metadata", None)
    if isinstance(response_metadata, dict):
        token_usage = response_metadata.get("token_usage")
        if isinstance(token_usage, dict):
            prompt_tokens = int(token_usage.get("prompt_tokens", 0) or 0)
            completion_tokens = int(token_usage.get("completion_tokens", 0) or 0)
            total_tokens = int(token_usage.get("total_tokens", prompt_tokens + completion_tokens) or 0)
            return {
                "input_tokens": prompt_tokens,
                "output_tokens": completion_tokens,
                "total_tokens": total_tokens,
            }

    return {"input_tokens": 0, "output_tokens": 0, "total_tokens": 0}

def combine_usage(*items: dict[str, int]) -> dict[str, int]:
    result = {"input_tokens": 0, "output_tokens": 0, "total_tokens": 0}
    for item in items:
        result["input_tokens"] += int(item.get("input_tokens", 0) or 0)
        result["output_tokens"] += int(item.get("output_tokens", 0) or 0)
        result["total_tokens"] += int(item.get("total_tokens", 0) or 0)
    return result