import { Low } from "lowdb";
import { JSONFile } from "lowdb/node";
import { DBSchema } from "./database.schema";
import { defaultAdminUser } from "./defaultAdminUser";
import path from "path";

// File path for db.json
const file = path.resolve(process.cwd(), "src/database/db.json");
const adapter = new JSONFile<DBSchema>(file);
const db = new Low<DBSchema>(adapter, {
  customers: [],
  users: [],
  userPermissions: [],
  permissions: [],
  customerDependants: [],
});

// Helper to generate next id for a collection
export function getNextId<T extends { id: number }>(items: T[]): number {
  if (!items || items.length === 0) return 1;
  return Math.max(...items.map((item) => item.id)) + 1;
}

// Initialize DB and ensure default admin user exists
export async function initDB() {
  await db.read();
  db.data ||= { customers: [], users: [], customerDependants: [], userPermissions: [], permissions: [] };
  if (db.data.users.length === 0) {
    db.data.users.push(defaultAdminUser);
    await db.write();
  }
}

export { db };