from neo4j import GraphDatabase
from flask import current_app

class Neo4jHandler:
    def __init__(self, uri, user, password):
        self.driver = GraphDatabase.driver(uri, auth=(user, password))

    def close(self):
        self.driver.close()

    def create_plant_node(self, uuid, name):
        with self.driver.session() as session:
            session.run(
                "MERGE (p:Plant {uuid: $uuid}) "
                "SET p.name = $name",
                uuid=uuid, name=name
            )

    def create_lineage(self, child_uuid, parent_uuid):
        with self.driver.session() as session:
            session.run(
                "MATCH (child:Plant {uuid: $child_uuid}), (parent:Plant {uuid: $parent_uuid}) "
                "MERGE (parent)-[:PARENT_OF]->(child)",
                child_uuid=child_uuid, parent_uuid=parent_uuid
            )

def get_neo4j_handler():
    uri = current_app.config['NEO4J_URI']
    user = current_app.config['NEO4J_USER']
    password = current_app.config['NEO4J_PASSWORD']
    return Neo4jHandler(uri, user, password)