from typing import Any, Dict, List, Optional, Union
from langchain.schema import AgentAction, AgentFinish, LLMResult
from langchain.callbacks.base import BaseCallbackHandler
import executor_pb2

class grpcCallbackHandler(BaseCallbackHandler):
    """Callback Handler that prints to std out."""
    
    def __init__(self, response_queue) -> None:
        """Initialize callback handler."""
        self.response_queue = response_queue

    def on_llm_start(
        self, serialized: Dict[str, Any], prompts: List[str], **kwargs: Any
    ) -> None:
        """Print out the prompts."""
        pass

    def on_llm_end(self, response: LLMResult, **kwargs: Any) -> None:
        """Do nothing."""
        pass

    def on_llm_new_token(self, token: str, **kwargs: Any) -> None:
        """Do nothing."""
        pass

    def on_llm_error(
        self, error: Union[Exception, KeyboardInterrupt], **kwargs: Any
    ) -> None:
        """Do nothing."""
        pass

    def on_chain_start(
        self, serialized: Dict[str, Any], inputs: Dict[str, Any], **kwargs: Any
    ) -> None:
        """Do nothing."""
        pass

    def on_chain_end(self, outputs: Dict[str, Any], **kwargs: Any) -> None:
        """Do nothing."""
        pass

    def on_chain_error(
        self, error: Union[Exception, KeyboardInterrupt], **kwargs: Any
    ) -> None:
        """Do nothing."""
        pass

    def on_tool_start(
        self,
        serialized: Dict[str, Any],
        input_str: str,
        **kwargs: Any,
    ) -> None:
        """Do nothing."""
        pass

    def on_agent_action(
        self, action: AgentAction, color: Optional[str] = None, **kwargs: Any
    ) -> Any:
        """Run on agent action."""
        self.response_queue.put(executor_pb2.ExecutorResponse(type=executor_pb2.ACTIONSTART, message=action.log))

    def on_tool_end(
        self,
        output: str,
        color: Optional[str] = None,
        observation_prefix: Optional[str] = None,
        llm_prefix: Optional[str] = None,
        **kwargs: Any,
    ) -> None:
        """If not the final action, print out observation."""
        self.response_queue.put(executor_pb2.ExecutorResponse(type=executor_pb2.ACTIONEND, message=output))

    def on_tool_error(
        self, error: Union[Exception, KeyboardInterrupt], **kwargs: Any
    ) -> None:
        """Do nothing."""
        pass

    def on_text(
        self,
        text: str,
        color: Optional[str] = None,
        end: str = "",
        **kwargs: Optional[str],
    ) -> None:
        """Do nothing."""
        pass

    def on_agent_finish(
        self, finish: AgentFinish, color: Optional[str] = None, **kwargs: Any
    ) -> None:
        """Run on agent end."""
        self.response_queue.put(executor_pb2.ExecutorResponse(type=executor_pb2.FINISHED, message=finish.log, answer=finish.return_values["output"]))