from __future__ import annotations

import json
import logging
from dataclasses import dataclass
from typing import Any, Callable

logger = logging.getLogger(__name__)


@dataclass(frozen=True)
class ToolDef:
    name: str
    description: str
    parameters: dict[str, Any]
    handler: Callable[..., str]


class ToolRegistry:
    def __init__(self):
        self._tools: dict[str, ToolDef] = {}

    def register(self, name: str, description: str, parameters: dict[str, Any]):
        """装饰器：将函数注册为工具。"""

        def decorator(fn: Callable[..., str]) -> Callable[..., str]:
            self._tools[name] = ToolDef(
                name=name,
                description=description,
                parameters=parameters,
                handler=fn,
            )
            logger.info("工具已注册: %s", name)
            return fn

        return decorator

    def get_openai_tools(self) -> list[dict[str, Any]]:
        return [
            {
                "type": "function",
                "function": {
                    "name": t.name,
                    "description": t.description,
                    "parameters": t.parameters,
                },
            }
            for t in self._tools.values()
        ]

    def execute(self, name: str, arguments_json: str) -> str:
        tool = self._tools.get(name)
        if tool is None:
            return f"错误：未知工具 '{name}'"
        try:
            kwargs = json.loads(arguments_json) if arguments_json.strip() else {}
            return tool.handler(**kwargs)
        except Exception as exc:
            logger.exception("工具 %s 执行失败", name)
            return f"工具 {name} 执行出错：{exc}"


tool_registry = ToolRegistry()