Add product data domain layer

src/app/core/products/models/product-domain.model.ts

@@ -0,0 +1,37 @@
+import { Category, Item } from '../../../models';
+
+export type Product = Item;
+export type ProductCategory = Category;
+export type ProductSort = 'relevance' | 'price_asc' | 'price_desc' | 'popular' | 'rating' | 'latest';
+
+export interface ProductFilters {
+  categoryIDs?: number[];
+  minPrice?: number;
+  maxPrice?: number;
+  tag?: string;
+  badges?: string[];
+  inStockOnly?: boolean;
+}
+
+export interface ProductListQuery extends ProductFilters {
+  count?: number;
+  skip?: number;
+  sort?: ProductSort;
+}
+
+export interface ProductSearchQuery extends ProductListQuery {
+  search: string;
+}
+
+export interface ProductListResult {
+  items: Product[];
+  total: number;
+  count: number;
+  skip: number;
+}
+
+export interface RelatedProductsQuery {
+  productID: number;
+  categoryID?: number;
+  count?: number;
+}

src/app/core/products/product-data-provider.token.ts

@@ -0,0 +1,20 @@
+import { InjectionToken, inject } from '@angular/core';
+import { RuntimeProviderStrategyService } from '../providers/runtime-provider-strategy.service';
+import { ApiProductDataProvider } from './providers/api-product-data.provider';
+import { ProductDataProvider } from './providers/product-data-provider.interface';
+
+export const PRODUCT_DATA_PROVIDER = new InjectionToken<ProductDataProvider>('PRODUCT_DATA_PROVIDER', {
+  providedIn: 'root',
+  factory: () => {
+    const strategy = inject(RuntimeProviderStrategyService);
+    const apiProvider = inject(ApiProductDataProvider);
+
+    switch (strategy.getProductProviderMode()) {
+      case 'mock':
+      case 'remote-config':
+      case 'api':
+      default:
+        return apiProvider;
+    }
+  }
+});

src/app/core/products/product-data.service.ts

@@ -0,0 +1,41 @@
+import { Injectable, inject } from '@angular/core';
+import { Observable } from 'rxjs';
+import { PRODUCT_DATA_PROVIDER } from './product-data-provider.token';
+import { Product, ProductCategory, ProductListQuery, ProductListResult, ProductSearchQuery, RelatedProductsQuery } from './models/product-domain.model';
+
+@Injectable({ providedIn: 'root' })
+export class ProductDataService {
+  private readonly provider = inject(PRODUCT_DATA_PROVIDER);
+
+  getProducts(query?: ProductListQuery): Observable<ProductListResult> {
+    return this.provider.getProducts(query);
+  }
+
+  getProduct(productID: number): Observable<Product> {
+    return this.provider.getProduct(productID);
+  }
+
+  getCategories(): Observable<ProductCategory[]> {
+    return this.provider.getCategories();
+  }
+
+  searchProducts(query: ProductSearchQuery): Observable<ProductListResult> {
+    return this.provider.searchProducts(query);
+  }
+
+  getFeaturedProducts(query?: ProductListQuery): Observable<ProductListResult> {
+    return this.provider.getFeaturedProducts(query);
+  }
+
+  getLatestProducts(query?: ProductListQuery): Observable<ProductListResult> {
+    return this.provider.getLatestProducts(query);
+  }
+
+  getProductsByCategory(categoryID: number, query?: ProductListQuery): Observable<ProductListResult> {
+    return this.provider.getProductsByCategory(categoryID, query);
+  }
+
+  getRelatedProducts(query: RelatedProductsQuery): Observable<ProductListResult> {
+    return this.provider.getRelatedProducts(query);
+  }
+}

src/app/core/products/providers/api-product-data.provider.ts

@@ -0,0 +1,75 @@
+import { Injectable } from '@angular/core';
+import { Observable, map } from 'rxjs';
+import { ApiService } from '../../../services';
+import { ProductDataProvider } from './product-data-provider.interface';
+import { Product, ProductCategory, ProductListQuery, ProductListResult, ProductSearchQuery, RelatedProductsQuery } from '../models/product-domain.model';
+
+@Injectable({ providedIn: 'root' })
+export class ApiProductDataProvider implements ProductDataProvider {
+  constructor(private readonly apiService: ApiService) {}
+
+  getProducts(query: ProductListQuery = {}): Observable<ProductListResult> {
+    return this.apiService.searchItems('', query.count, query.skip, this.toSearchOptions(query))
+      .pipe(map(result => this.toResult(result.items, result.total, query)));
+  }
+
+  getProduct(productID: number): Observable<Product> {
+    return this.apiService.getItem(productID);
+  }
+
+  getCategories(): Observable<ProductCategory[]> {
+    return this.apiService.getCategories();
+  }
+
+  searchProducts(query: ProductSearchQuery): Observable<ProductListResult> {
+    return this.apiService.searchItems(query.search, query.count, query.skip, this.toSearchOptions(query))
+      .pipe(map(result => this.toResult(result.items, result.total, query)));
+  }
+
+  getFeaturedProducts(query: ProductListQuery = {}): Observable<ProductListResult> {
+    return this.apiService.getRandomItems(query.count ?? 10)
+      .pipe(map(items => this.toResult(items, items.length, query)));
+  }
+
+  getLatestProducts(query: ProductListQuery = {}): Observable<ProductListResult> {
+    return this.apiService.searchItems('', query.count, query.skip, { ...this.toSearchOptions(query), sort: 'popular' })
+      .pipe(map(result => this.toResult(result.items, result.total, query)));
+  }
+
+  getProductsByCategory(categoryID: number, query: ProductListQuery = {}): Observable<ProductListResult> {
+    return this.apiService.getCategoryItems(categoryID, query.count, query.skip)
+      .pipe(map(items => this.toResult(items, items.length, query)));
+  }
+
+  getRelatedProducts(query: RelatedProductsQuery): Observable<ProductListResult> {
+    if (query.categoryID == null) {
+      return this.getFeaturedProducts({ count: query.count ?? 8 });
+    }
+
+    return this.getProductsByCategory(query.categoryID, { count: query.count ?? 8 }).pipe(
+      map(result => ({
+        ...result,
+        items: result.items.filter(item => item.itemID !== query.productID)
+      }))
+    );
+  }
+
+  private toSearchOptions(query: ProductListQuery) {
+    return {
+      categoryIDs: query.categoryIDs,
+      minPrice: query.minPrice,
+      maxPrice: query.maxPrice,
+      tag: query.tag,
+      sort: query.sort === 'latest' ? 'popular' : query.sort
+    };
+  }
+
+  private toResult(items: Product[], total: number, query: ProductListQuery): ProductListResult {
+    return {
+      items,
+      total,
+      count: query.count ?? items.length,
+      skip: query.skip ?? 0
+    };
+  }
+}

src/app/core/products/providers/product-data-provider.interface.ts

@@ -0,0 +1,13 @@
+import { Observable } from 'rxjs';
+import { Product, ProductCategory, ProductListQuery, ProductListResult, ProductSearchQuery, RelatedProductsQuery } from '../models/product-domain.model';
+
+export interface ProductDataProvider {
+  getProducts(query?: ProductListQuery): Observable<ProductListResult>;
+  getProduct(productID: number): Observable<Product>;
+  getCategories(): Observable<ProductCategory[]>;
+  searchProducts(query: ProductSearchQuery): Observable<ProductListResult>;
+  getFeaturedProducts(query?: ProductListQuery): Observable<ProductListResult>;
+  getLatestProducts(query?: ProductListQuery): Observable<ProductListResult>;
+  getProductsByCategory(categoryID: number, query?: ProductListQuery): Observable<ProductListResult>;
+  getRelatedProducts(query: RelatedProductsQuery): Observable<ProductListResult>;
+}

src/app/core/providers/runtime-provider-strategy.service.ts

@@ -20,4 +20,12 @@ export class RuntimeProviderStrategyService {
 
     return 'api';
   }
+
+  getProductProviderMode(): RuntimeProviderMode {
+    if (environment.useMockData) {
+      return 'mock';
+    }
+
+    return 'api';
+  }
 }