Add category browsing and product filtering with breadcrumbs

src/FrontOffice.Main/Utilities/ProductService.cs

@@ -1,7 +1,10 @@
+using System;
 using System.Collections.Concurrent;
 using System.Collections.Generic;
+using System.Diagnostics.CodeAnalysis;
 using System.Linq;
 using FrontOffice.BFF.Products.Protobuf.Protos.Products;
+using Google.Protobuf.WellKnownTypes;
 
 namespace FrontOffice.Main.Utilities;
 
@@ -46,7 +49,8 @@ public record ProductCategoryPathInfo(
 
 public class ProductService
 {
-    private readonly ConcurrentDictionary<long, Product> _cache = new();
+    private readonly ConcurrentDictionary<long, CacheEntry> _cache = new();
+    private static readonly TimeSpan CacheDuration = TimeSpan.FromMinutes(1);
     private readonly ProductsContract.ProductsContractClient _client;
 
     public ProductService(ProductsContract.ProductsContractClient client)
@@ -54,11 +58,11 @@ public class ProductService
         _client = client;
     }
 
-    public async Task<List<Product>> GetProductsAsync(string? query = null)
+    public async Task<List<Product>> GetProductsAsync(string? query = null, long? categoryId = null)
     {
         try
         {
-            var resp = await _client.GetAllProductsByFilterAsync(new GetAllProductsByFilterRequest
+            var request = new GetAllProductsByFilterRequest
             {
                 Filter = new GetAllProductsByFilterFilter
                 {
@@ -67,12 +71,19 @@ public class ProductService
                     ShortInfomation = query ?? string.Empty,
                     FullInformation = query ?? string.Empty
                 }
-            });
+            };
+
+            if (categoryId is { } value)
+            {
+                request.Filter.CategoryId = value ;
+            }
+
+            var resp = await _client.GetAllProductsByFilterAsync(request);
             return MapAndCache(resp.Models);
         }
         catch
         {
-            IEnumerable<Product> list = _cache.Values;
+            IEnumerable<Product> list = GetValidCachedProducts();
             if (!string.IsNullOrWhiteSpace(query))
             {
                 var q = query.Trim();
@@ -87,7 +98,7 @@ public class ProductService
 
     public async Task<Product?> GetByIdAsync(long id)
     {
-        if (_cache.TryGetValue(id, out var cached)) return cached;
+        if (TryGetCachedProduct(id, out var cached)) return cached;
 
         try
         {
@@ -101,7 +112,7 @@ public class ProductService
         }
         catch
         {
-            _cache.TryGetValue(id, out var result);
+            TryGetCachedProduct(id, out var result);
             return result;
         }
     }
@@ -123,9 +134,7 @@ public class ProductService
                 Rate: m.Rate,
                 RemainingCount: m.RemainingCount
             );
-            if (_cache.All(a => a.Key != p.Id))
-                _cache[p.Id] = p;
-
+            CacheProduct(p);
 
             list.Add(p);
         }
@@ -159,10 +168,42 @@ public class ProductService
             Categories = MapCategoryPaths(model.Categories)
         };
 
-        _cache[product.Id] = product;
+        CacheProduct(product);
         return product;
     }
 
+    private void CacheProduct(Product product)
+    {
+        var entry = new CacheEntry(product, DateTime.UtcNow.Add(CacheDuration));
+        _cache.AddOrUpdate(product.Id, entry, (_, _) => entry);
+    }
+
+    private bool TryGetCachedProduct(long id, [NotNullWhen(true)] out Product? product)
+    {
+        if (_cache.TryGetValue(id, out var entry))
+        {
+            if (entry.Expiration > DateTime.UtcNow)
+            {
+                product = entry.Product;
+                return true;
+            }
+
+            _cache.TryRemove(id, out _);
+        }
+
+        product = null;
+        return false;
+    }
+
+    private IEnumerable<Product> GetValidCachedProducts()
+    {
+        var now = DateTime.UtcNow;
+        return _cache.Values
+            .Where(entry => entry.Expiration > now)
+            .Select(entry => entry.Product);
+    }
+    
+    private sealed record CacheEntry(Product Product, DateTime Expiration);
     private static string BuildUrl(string? path) =>
         string.IsNullOrWhiteSpace(path) ? string.Empty : UrlUtility.DownloadUrl + path;