from langchain_community.graphs.graph_document import (
    Node as BaseNode,
    Relationship as BaseRelationship,
)
from langchain.schema import Document
from typing import List, Dict, Any, Optional
from langchain.pydantic_v1 import Field, BaseModel

class Property(BaseModel):
    """A single property consisting of key and value"""
    key: str = Field(..., description="key")
    value: str = Field(..., description="value")

class Node(BaseNode):
    properties: Optional[List[Property]] = Field(
        None, description="List of node properties")

class Relationship(BaseRelationship):
    properties: Optional[List[Property]] = Field(
        None, description="List of relationship properties"
    )

class KnowledgeGraph(BaseModel):
    """Generate a knowledge graph with entities and relationships."""
    nodes: List[Node] = Field(..., description="List of nodes in the knowledge graph")
    rels: List[Relationship] = Field(..., description="List of relationships in the knowledge graph")