refactor: wip to nestjs

packages/server-nest/src/modules/Bills/queries/GetDueBills.service.ts

@@ -0,0 +1,23 @@
+import { Injectable } from '@nestjs/common';
+import { Bill } from '../models/Bill';
+
+@Injectable()
+export class GetDueBills {
+  constructor(private billModel: typeof Bill) {}
+
+  /**
+   * Retrieve all due bills or for specific given vendor id.
+   * @param {number} vendorId -
+   */
+  public async getDueBills(vendorId?: number): Promise<Bill[]> {
+    const dueBills = await this.billModel.query().onBuild((query) => {
+      query.orderBy('bill_date', 'DESC');
+      query.modify('dueBills');
+
+      if (vendorId) {
+        query.where('vendor_id', vendorId);
+      }
+    });
+    return dueBills;
+  }
+}