add lowdb

src/database/database.ts

@@ -0,0 +1,33 @@
+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: [],
+  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: [] };
+  if (db.data.users.length === 0) {
+    db.data.users.push(defaultAdminUser);
+    await db.write();
+  }
+}
+
+export { db };