feat(persistance) : add DAO

src/app/dao/ProductEstablishmentDAO.ts

@@ -0,0 +1,55 @@
+import { Injectable } from '@angular/core';
+import { Establishment } from '../models/Establishment';
+import { Product } from '../models/Product';
+import { ProductEstablishment } from '../models/ProductEstablisment';
+import { Chain } from '../models/Chain';
+import { DBProductEstablishment } from '../models/db/DBProductEstablishment';
+import { ComposedDAO } from './ComposedDAO';
+
+@Injectable({
+  providedIn: 'root',
+})
+export class ProductEstablishmentDAO extends ComposedDAO<
+  ProductEstablishment,
+  DBProductEstablishment,
+  ProductEstablishmentQueryResult
+> {
+  constructor() {
+    super(
+      'product_establishment',
+      `
+    SELECT pe.id, pe.product_id, pe.establishment_id, p.barcode, p.image as product_image, p.name as product_name,
+    e.address, e.chain_id, c.image as chain_image, c.name as chain_name FROM product_establishment pe 
+    JOIN product p ON p.id = pe.product_id 
+    JOIN establishment e ON e.id = pe.establishment_id 
+    JOIN chain c ON c.id = e.chain_id;`,
+      'pe'
+    );
+  }
+
+  protected override toDB(model: ProductEstablishment): DBProductEstablishment {
+    if (!model.product.id) throw new Error('Product id is required');
+    if (!model.establishment.id) throw new Error('Establishment id is required');
+    return new DBProductEstablishment(model.product.id, model.establishment.id, model.id);
+  }
+
+  protected override fromDB(qR: ProductEstablishmentQueryResult): ProductEstablishment {
+    const chain = new Chain(qR.chain_name, qR.chain_image, qR.chain_id);
+    const establishment = new Establishment(chain, qR.address, qR.establishment_id);
+    const product = new Product(qR.barcode, qR.product_name, qR.product_image, qR.product_id);
+    return new ProductEstablishment(product, establishment, qR.id);
+  }
+}
+
+type ProductEstablishmentQueryResult = {
+  address: string;
+  barcode: string;
+  chain_id: number;
+  chain_image: string | null;
+  chain_name: string;
+  establishment_id: number;
+  id: number;
+  product_id: number;
+  product_image: string | null;
+  product_name: string;
+};