import { drizzle } from "drizzle-orm/node-postgres";
import { Pool } from "pg";
import * as schema from "./schema.js";

export { schema };
export * from "./schema.js";

export type Database = ReturnType<typeof drizzle<typeof schema>>;

let pool: Pool | undefined;
let dbInstance: Database | undefined;

/** Lazily-constructed singleton Drizzle client (Node postgres driver). */
export function getDb(connectionString = process.env.DATABASE_URL): Database {
  if (!connectionString) {
    throw new Error("DATABASE_URL is not set");
  }
  if (!dbInstance) {
    pool = new Pool({ connectionString });
    dbInstance = drizzle(pool, { schema });
  }
  return dbInstance;
}

export async function closeDb(): Promise<void> {
  await pool?.end();
  pool = undefined;
  dbInstance = undefined;
}