"""
工具注册表 - 支持动态工具发现和加载

提供插件化架构，允许通过配置动态加载和替换工具。
"""
import logging
from typing import Any, Callable, Dict, List, Optional, Type

logger = logging.getLogger(__name__)


class ToolRegistry:
    """工具注册表 - 管理所有可用工具的注册和获取"""
    
    def __init__(self):
        self._tools: Dict[str, Any] = {}
        self._tool_info: Dict[str, Dict] = {}
    
    def register(self, name: str, tool_class: Any, metadata: Optional[Dict] = None) -> None:
        """
        注册工具到注册表
        
        Args:
            name: 工具名称（唯一标识）
            tool_class: 工具类或工厂函数
            metadata: 工具元数据（描述、版本、作者等）
        """
        if name in self._tools:
            logger.warning(f"Tool '{name}' already registered, overwriting")
        
        self._tools[name] = tool_class
        self._tool_info[name] = metadata or {}
        logger.info(f"Registered tool: {name}")
    
    def get(self, name: str) -> Any:
        """
        获取已注册的工具
        
        Args:
            name: 工具名称
            
        Returns:
            工具类或工厂函数
            
        Raises:
            KeyError: 工具未注册
        """
        if name not in self._tools:
            raise KeyError(f"Tool '{name}' not registered. Available tools: {list(self._tools.keys())}")
        return self._tools[name]
    
    def get_instance(self, name: str, *args, **kwargs) -> Any:
        """
        获取工具实例（调用注册的类或工厂函数）
        
        Args:
            name: 工具名称
            *args: 位置参数
            **kwargs: 关键字参数
            
        Returns:
            工具实例
        """
        tool = self.get(name)
        if callable(tool):
            return tool(*args, **kwargs)
        return tool
    
    def list_tools(self) -> List[str]:
        """列出所有已注册的工具名称"""
        return list(self._tools.keys())
    
    def get_info(self, name: str) -> Dict:
        """获取工具元数据"""
        return self._tool_info.get(name, {})
    
    def unregister(self, name: str) -> bool:
        """
        注销工具
        
        Args:
            name: 工具名称
            
        Returns:
            是否成功注销
        """
        if name in self._tools:
            del self._tools[name]
            del self._tool_info[name]
            logger.info(f"Unregistered tool: {name}")
            return True
        return False
    
    def has(self, name: str) -> bool:
        """检查工具是否已注册"""
        return name in self._tools
    
    def clear(self) -> None:
        """清除所有已注册的工具"""
        self._tools.clear()
        self._tool_info.clear()
        logger.info("Cleared all registered tools")


# 全局注册表实例
_global_registry: Optional[ToolRegistry] = None


def get_registry() -> ToolRegistry:
    """获取全局工具注册表实例"""
    global _global_registry
    if _global_registry is None:
        _global_registry = ToolRegistry()
        _register_default_tools()
    return _global_registry


def _register_default_tools() -> None:
    """注册默认工具"""
    global _global_registry
    
    # 延迟导入避免循环依赖
    try:
        from runners import CobolRunner, NativeJavaRunner, SparkJavaRunner
        from runners.gixsql_runner import GixsqlCobolRunner
        from agents.llm import LLMClient
        from comparator import FieldComparator
        
        _global_registry.register("cobol_runner", CobolRunner, 
                                  {"type": "runner", "description": "COBOL compiler and runner"})
        _global_registry.register("java_runner", NativeJavaRunner,
                                  {"type": "runner", "description": "Java native runner"})
        _global_registry.register("spark_runner", SparkJavaRunner,
                                  {"type": "runner", "description": "Spark Java runner"})
        _global_registry.register("gixsql_runner", GixsqlCobolRunner,
                                  {"type": "runner", "description": "DB COBOL runner with gixsql"})
        _global_registry.register("llm_client", LLMClient,
                                  {"type": "agent", "description": "LLM API client"})
        _global_registry.register("comparator", FieldComparator,
                                  {"type": "comparator", "description": "Field-level comparison"})
        
        logger.info(f"Registered {len(_global_registry.list_tools())} default tools")
    except ImportError as e:
        logger.warning(f"Failed to register default tools: {e}")


class ToolConfig:
    """工具配置 - 从配置文件或环境变量加载工具配置"""
    
    @staticmethod
    def get_runner_mode(config: Dict) -> str:
        """获取运行器模式"""
        return config.get("runner_mode", "native")
    
    @staticmethod
    def get_runner_class(registry: ToolRegistry, mode: str) -> Any:
        """根据模式获取运行器类"""
        runner_map = {
            "native": "java_runner",
            "spark": "spark_runner",
            "cobol": "cobol_runner",
        }
        tool_name = runner_map.get(mode, "java_runner")
        return registry.get(tool_name)
    
    @staticmethod
    def get_llm_config(config: Dict) -> Dict:
        """获取LLM配置"""
        return {
            "model": config.get("llm_model", None),
            "timeout": config.get("llm_timeout", 15),
            "cache_dir": config.get("llm_cache_dir", ".cache/llm"),
        }