import Knex from 'knex';
import type { Knex as KnexType } from 'knex';
import { Model } from 'objection';
import { CentralTenant, CentralDomain, CentralUser } from '../models/central.model';

let centralKnex: KnexType | null = null;

/**
 * Get or create a Knex instance for the central database
 * This is used for Objection models that work with central entities
 */
export function getCentralKnex(): KnexType {
  if (!centralKnex) {
    const centralDbUrl = process.env.CENTRAL_DATABASE_URL;
    
    if (!centralDbUrl) {
      throw new Error('CENTRAL_DATABASE_URL environment variable is not set');
    }

    centralKnex = Knex({
      client: 'mysql2',
      connection: centralDbUrl,
      pool: {
        min: 2,
        max: 10,
      },
    });

    // Bind Objection models to this knex instance
    Model.knex(centralKnex);
  }

  return centralKnex;
}

/**
 * Initialize central models with the knex instance
 */
export function initCentralModels() {
  const knex = getCentralKnex();
  CentralTenant.knex(knex);
  CentralDomain.knex(knex);
  CentralUser.knex(knex);
}