import { ArangoDBService } from './arangodb';

/**
 * Load triples from ArangoDB for use with the TXT2KG dataset
 * @param url ArangoDB connection URL
 * @param dbName ArangoDB database name
 * @param username ArangoDB username
 * @param password ArangoDB password 
 * @returns Array of triples in the format expected by create_remote_backend_from_triplets
 */
export async function loadTriplesFromArangoDB(
  url?: string,
  dbName?: string,
  username?: string,
  password?: string
): Promise<string[]> {
  try {
    // Get the ArangoDB service instance
    const arangoService = ArangoDBService.getInstance();
    
    // Initialize the connection if not already initialized
    if (!arangoService.isInitialized()) {
      await arangoService.initialize(url, dbName, username, password);
    }
    
    // Query to get all triples from ArangoDB
    const query = `
      FOR e IN relationships
      LET subject = DOCUMENT(e._from).name
      LET object = DOCUMENT(e._to).name
      LET predicate = e.type
      RETURN subject + " " + predicate + " " + object
    `;
    
    // Execute the query
    const results = await arangoService.executeQuery(query);
    
    // Format the triples as strings in the format "subject predicate object"
    const triples = results.map(triple => triple);
    
    console.log(`Loaded ${triples.length} triples from ArangoDB`);
    return triples;
  } catch (error) {
    console.error('Error loading triples from ArangoDB:', error);
    throw error;
  }
}