from abc import ABC, abstractmethod
from typing import Any, Dict
from .spec import AgentManifest, Graph, AgentMetadata, AgentVersion, SecurityPolicy, LLMNodeModel, Edge, NodeType

class BaseConverter(ABC):
    """
    Abstract base class for converting external agent formats into LARASpec.
    """
    @abstractmethod
    def convert(self, source: Any) -> AgentManifest:
        """
        Converts the source object into an AgentManifest.
        """
        pass

class LangChainConverter(BaseConverter):
    """
    Skeleton converter for LangChain Graphs (LangGraph).
    """
    def convert(self, source: Any) -> AgentManifest:
        """
        Accepts a LangChain Graph object (or dict representation) and converts it.
        Note: This is a skeleton implementation. Real conversion requires deep inspection of LangChain internals.
        """
        # 1. Create Basic Manifest Structure
        manifest = AgentManifest(
            metadata=AgentMetadata(
                name="Imported LangChain Agent",
                author="LangChain Converter",
                description="Converted from LangGraph"
            ),
            version={
                "version": "0.1.0"
            },
            graph=Graph(
                nodes=[],
                edges=[],
                start_node="start" # Placeholder
            )
        )
        
        # 2. Inspect Source (Hypothetical Inspection)
        # In a real implementation, we would traverse source.nodes and source.edges
        
        # Example: Create a dummy start node
        start_node = LLMNodeModel(
            id="node_1",
            type=NodeType.LLM,
            label="Converted LLM Node",
            model_name="gpt-4", # Default or extracted
            prompt_template="You are a helpful assistant.",
            output_key="response"
        )
        manifest.graph.nodes.append(start_node)
        manifest.graph.start_node = start_node.id
        
        # Example: Add an edge
        # manifest.graph.edges.append(Edge(source="start", target="node_1"))
        
        return manifest
