define basic shopping cart behaviors

FakePieShop/Controllers/ShoppingCartController.cs

@@ -0,0 +1,52 @@
+using FakePieShop.Models;
+using FakePieShop.Models.ViewModels;
+using Microsoft.AspNetCore.Mvc;
+
+namespace FakePieShop.Controllers
+{
+    public class ShoppingCartController : Controller
+    {
+        private readonly IPieRepository _pieRepository;
+        private readonly IShoppingCart _shoppingCart;
+
+        public ShoppingCartController(IPieRepository pieRepository, IShoppingCart shoppingCart)
+        {
+            _pieRepository = pieRepository;
+            _shoppingCart = shoppingCart;
+        }
+
+        public ViewResult Index()
+        {
+            var items = _shoppingCart.GetShoppingCartItems();
+            _shoppingCart.ShoppingCartItems = items;
+
+            var shoppingCartViewModel = new ShoppingCartViewModel(_shoppingCart, _shoppingCart.GetShoppingCartTotal());
+
+            return View(shoppingCartViewModel);
+        }
+
+        public RedirectToActionResult AddToShoppingCart(int pieId)
+        {
+            var selectedPie = _pieRepository.GetPieById(pieId);
+
+            if (selectedPie != null)
+            {
+                _shoppingCart.AddToCart(selectedPie);
+            }
+
+            return RedirectToAction("Index");
+        }
+
+        public RedirectToActionResult RemoveFromShoppingCart(int pieId)
+        {
+            var selectedPie = _pieRepository.GetPieById(pieId);
+
+            if (selectedPie != null)
+            {
+                _shoppingCart.RemoveFromCart(selectedPie);
+            }
+
+            return RedirectToAction("Index");
+        }
+    }
+}

FakePieShop/Migrations/20231103172053_AddShoppingCartItem.Designer.cs

@@ -0,0 +1,146 @@
+// <auto-generated />
+using FakePieShop.Models;
+using Microsoft.EntityFrameworkCore;
+using Microsoft.EntityFrameworkCore.Infrastructure;
+using Microsoft.EntityFrameworkCore.Metadata;
+using Microsoft.EntityFrameworkCore.Migrations;
+using Microsoft.EntityFrameworkCore.Storage.ValueConversion;
+
+#nullable disable
+
+namespace FakePieShop.Migrations
+{
+    [DbContext(typeof(FakePieShopDbContext))]
+    [Migration("20231103172053_AddShoppingCartItem")]
+    partial class AddShoppingCartItem
+    {
+        /// <inheritdoc />
+        protected override void BuildTargetModel(ModelBuilder modelBuilder)
+        {
+#pragma warning disable 612, 618
+            modelBuilder
+                .HasAnnotation("ProductVersion", "7.0.13")
+                .HasAnnotation("Relational:MaxIdentifierLength", 128);
+
+            SqlServerModelBuilderExtensions.UseIdentityColumns(modelBuilder);
+
+            modelBuilder.Entity("FakePieShop.Models.Category", b =>
+                {
+                    b.Property<int>("CategoryId")
+                        .ValueGeneratedOnAdd()
+                        .HasColumnType("int");
+
+                    SqlServerPropertyBuilderExtensions.UseIdentityColumn(b.Property<int>("CategoryId"));
+
+                    b.Property<string>("CategoryName")
+                        .IsRequired()
+                        .HasColumnType("nvarchar(max)");
+
+                    b.Property<string>("Description")
+                        .HasColumnType("nvarchar(max)");
+
+                    b.HasKey("CategoryId");
+
+                    b.ToTable("Categories");
+                });
+
+            modelBuilder.Entity("FakePieShop.Models.Pie", b =>
+                {
+                    b.Property<int>("PieId")
+                        .ValueGeneratedOnAdd()
+                        .HasColumnType("int");
+
+                    SqlServerPropertyBuilderExtensions.UseIdentityColumn(b.Property<int>("PieId"));
+
+                    b.Property<string>("AllergyInformation")
+                        .HasColumnType("nvarchar(max)");
+
+                    b.Property<int>("CategoryId")
+                        .HasColumnType("int");
+
+                    b.Property<string>("ImageThumbnailUrl")
+                        .HasColumnType("nvarchar(max)");
+
+                    b.Property<string>("ImageUrl")
+                        .HasColumnType("nvarchar(max)");
+
+                    b.Property<bool>("InStock")
+                        .HasColumnType("bit");
+
+                    b.Property<bool>("IsPieOfTheWeek")
+                        .HasColumnType("bit");
+
+                    b.Property<string>("LongDescription")
+                        .HasColumnType("nvarchar(max)");
+
+                    b.Property<string>("Name")
+                        .IsRequired()
+                        .HasColumnType("nvarchar(max)");
+
+                    b.Property<decimal>("Price")
+                        .HasColumnType("decimal(18,2)");
+
+                    b.Property<string>("ShortDescription")
+                        .HasColumnType("nvarchar(max)");
+
+                    b.HasKey("PieId");
+
+                    b.HasIndex("CategoryId");
+
+                    b.ToTable("Pies");
+                });
+
+            modelBuilder.Entity("FakePieShop.Models.ShoppingCartItem", b =>
+                {
+                    b.Property<int>("ShoppingCartItemId")
+                        .ValueGeneratedOnAdd()
+                        .HasColumnType("int");
+
+                    SqlServerPropertyBuilderExtensions.UseIdentityColumn(b.Property<int>("ShoppingCartItemId"));
+
+                    b.Property<int>("Amount")
+                        .HasColumnType("int");
+
+                    b.Property<int>("PieId")
+                        .HasColumnType("int");
+
+                    b.Property<string>("ShoppingCartId")
+                        .HasColumnType("nvarchar(max)");
+
+                    b.HasKey("ShoppingCartItemId");
+
+                    b.HasIndex("PieId");
+
+                    b.ToTable("ShoppingCartItems");
+                });
+
+            modelBuilder.Entity("FakePieShop.Models.Pie", b =>
+                {
+                    b.HasOne("FakePieShop.Models.Category", "Category")
+                        .WithMany("Pies")
+                        .HasForeignKey("CategoryId")
+                        .OnDelete(DeleteBehavior.Cascade)
+                        .IsRequired();
+
+                    b.Navigation("Category");
+                });
+
+            modelBuilder.Entity("FakePieShop.Models.ShoppingCartItem", b =>
+                {
+                    b.HasOne("FakePieShop.Models.Pie", "Pie")
+                        .WithMany()
+                        .HasForeignKey("PieId")
+                        .OnDelete(DeleteBehavior.Cascade)
+                        .IsRequired();
+
+                    b.Navigation("Pie");
+                });
+
+            modelBuilder.Entity("FakePieShop.Models.Category", b =>
+                {
+                    b.Navigation("Pies");
+                });
+#pragma warning restore 612, 618
+        }
+    }
+}

FakePieShop/Migrations/20231103172053_AddShoppingCartItem.cs

@@ -0,0 +1,47 @@
+using Microsoft.EntityFrameworkCore.Migrations;
+
+#nullable disable
+
+namespace FakePieShop.Migrations
+{
+    /// <inheritdoc />
+    public partial class AddShoppingCartItem : Migration
+    {
+        /// <inheritdoc />
+        protected override void Up(MigrationBuilder migrationBuilder)
+        {
+            migrationBuilder.CreateTable(
+                name: "ShoppingCartItems",
+                columns: table => new
+                {
+                    ShoppingCartItemId = table.Column<int>(type: "int", nullable: false)
+                        .Annotation("SqlServer:Identity", "1, 1"),
+                    PieId = table.Column<int>(type: "int", nullable: false),
+                    Amount = table.Column<int>(type: "int", nullable: false),
+                    ShoppingCartId = table.Column<string>(type: "nvarchar(max)", nullable: true)
+                },
+                constraints: table =>
+                {
+                    table.PrimaryKey("PK_ShoppingCartItems", x => x.ShoppingCartItemId);
+                    table.ForeignKey(
+                        name: "FK_ShoppingCartItems_Pies_PieId",
+                        column: x => x.PieId,
+                        principalTable: "Pies",
+                        principalColumn: "PieId",
+                        onDelete: ReferentialAction.Cascade);
+                });
+
+            migrationBuilder.CreateIndex(
+                name: "IX_ShoppingCartItems_PieId",
+                table: "ShoppingCartItems",
+                column: "PieId");
+        }
+
+        /// <inheritdoc />
+        protected override void Down(MigrationBuilder migrationBuilder)
+        {
+            migrationBuilder.DropTable(
+                name: "ShoppingCartItems");
+        }
+    }
+}

FakePieShop/Migrations/FakePieShopDbContextModelSnapshot.cs

@@ -87,6 +87,30 @@ namespace FakePieShop.Migrations
                     b.ToTable("Pies");
                 });
 
+            modelBuilder.Entity("FakePieShop.Models.ShoppingCartItem", b =>
+                {
+                    b.Property<int>("ShoppingCartItemId")
+                        .ValueGeneratedOnAdd()
+                        .HasColumnType("int");
+
+                    SqlServerPropertyBuilderExtensions.UseIdentityColumn(b.Property<int>("ShoppingCartItemId"));
+
+                    b.Property<int>("Amount")
+                        .HasColumnType("int");
+
+                    b.Property<int>("PieId")
+                        .HasColumnType("int");
+
+                    b.Property<string>("ShoppingCartId")
+                        .HasColumnType("nvarchar(max)");
+
+                    b.HasKey("ShoppingCartItemId");
+
+                    b.HasIndex("PieId");
+
+                    b.ToTable("ShoppingCartItems");
+                });
+
             modelBuilder.Entity("FakePieShop.Models.Pie", b =>
                 {
                     b.HasOne("FakePieShop.Models.Category", "Category")
@@ -98,6 +122,17 @@ namespace FakePieShop.Migrations
                     b.Navigation("Category");
                 });
 
+            modelBuilder.Entity("FakePieShop.Models.ShoppingCartItem", b =>
+                {
+                    b.HasOne("FakePieShop.Models.Pie", "Pie")
+                        .WithMany()
+                        .HasForeignKey("PieId")
+                        .OnDelete(DeleteBehavior.Cascade)
+                        .IsRequired();
+
+                    b.Navigation("Pie");
+                });
+
             modelBuilder.Entity("FakePieShop.Models.Category", b =>
                 {
                     b.Navigation("Pies");

FakePieShop/Models/FakePieShopDbContext.cs

@@ -11,5 +11,6 @@ namespace FakePieShop.Models
 
         public DbSet<Category> Categories { get; set; }
         public DbSet<Pie> Pies { get; set; }
+        public DbSet<ShoppingCartItem> ShoppingCartItems { get; set; }
     }
 }

FakePieShop/Models/IShoppingCart.cs

@@ -0,0 +1,12 @@
+namespace FakePieShop.Models
+{
+    public interface IShoppingCart
+    {
+        void AddToCart(Pie pie);
+        int RemoveFromCart(Pie pie);
+        List<ShoppingCartItem> GetShoppingCartItems();
+        void ClearCart();
+        decimal GetShoppingCartTotal();
+        List<ShoppingCartItem> ShoppingCartItems { get; set; }
+    }
+}

FakePieShop/Models/ShoppingCart.cs

@@ -0,0 +1,116 @@
+using Microsoft.EntityFrameworkCore;
+
+namespace FakePieShop.Models
+{
+    public class ShoppingCart : IShoppingCart
+    {
+        private readonly FakePieShopDbContext _fakePieShopDbContext;
+        public string? ShoppingCartId { get; set; }
+        public List<ShoppingCartItem>? ShoppingCartItems { get; set; }
+        private ShoppingCart(FakePieShopDbContext fakePieShopDbContext)
+        {
+            _fakePieShopDbContext = fakePieShopDbContext;
+        }
+
+        public static ShoppingCart GetCart(IServiceProvider services)
+        {
+            ISession? session = services.GetRequiredService<IHttpContextAccessor>()?
+                .HttpContext?.Session;
+
+            FakePieShopDbContext context = services.GetService<FakePieShopDbContext>() ?? throw new Exception("Unable to initialize DB context");
+
+            // check for an existing cart; if there is no session, or a cart with this id does not exist,
+            // generate a new GUID
+            string cartId = session?.GetString("CartId") ?? Guid.NewGuid().ToString();
+
+            // update the session with the new cart id, if one was generated
+            session?.SetString("CartId", cartId);
+
+            return new ShoppingCart(context) { ShoppingCartId = cartId };
+        }
+
+        private ShoppingCartItem? FindItemInCart(Pie pie)
+        {
+            return _fakePieShopDbContext.ShoppingCartItems.SingleOrDefault(
+                s => s.Pie.PieId == pie.PieId && s.ShoppingCartId == ShoppingCartId);
+        }
+
+        public void AddToCart(Pie pie)
+        {
+            ShoppingCartItem? shoppingCartItem = FindItemInCart(pie);
+
+            if (shoppingCartItem == null)
+            {
+                ShoppingCartItem newItem = new()
+                {
+                    ShoppingCartId = ShoppingCartId,
+                    Pie = pie,
+                    Amount = 1,
+                };
+
+                _fakePieShopDbContext.ShoppingCartItems.Add(newItem);
+            }
+            else
+            {
+                shoppingCartItem.Amount++;
+            }
+
+            _fakePieShopDbContext.SaveChanges();
+        }
+
+        public int RemoveFromCart(Pie pie)
+        {
+            ShoppingCartItem? shoppingCartItem = FindItemInCart(pie);
+
+            int itemCount = 0;
+
+            if (shoppingCartItem != null)
+            {
+                if (shoppingCartItem.Amount > 1)
+                {
+                    shoppingCartItem.Amount--;
+                    itemCount = shoppingCartItem.Amount;
+                }
+                else
+                {
+                    _fakePieShopDbContext.ShoppingCartItems.Remove(shoppingCartItem);
+                }
+            }
+
+            _fakePieShopDbContext.SaveChanges();
+            return itemCount;
+        }
+
+        public List<ShoppingCartItem> GetShoppingCartItems()
+        {
+            // if we have shopping cart items defined already, use that.
+            // otherwise, we querty the database for these items, and then
+            // assign them to our instance state.
+            return ShoppingCartItems ??=
+                _fakePieShopDbContext.ShoppingCartItems.Where(cart =>
+                    cart.ShoppingCartId == ShoppingCartId)
+                    .Include(s => s.Pie)
+                    .ToList();
+        }
+
+        public void ClearCart()
+        {
+            var items = _fakePieShopDbContext.ShoppingCartItems
+                .Where(cart => cart.ShoppingCartId == ShoppingCartId);
+
+            _fakePieShopDbContext.RemoveRange(items);
+            _fakePieShopDbContext.SaveChanges();
+        }
+
+        public decimal GetShoppingCartTotal()
+        {
+            return _fakePieShopDbContext.ShoppingCartItems.Where
+                // all the items associated with this cart
+                (item => item.ShoppingCartId == ShoppingCartId)
+                // the product of price * amount for each of these
+                .Select(item => item.Pie.Price * item.Amount)
+                // finally, the sum of these calculations.
+                .Sum();
+        }
+    }
+}

FakePieShop/Models/ShoppingCartItem.cs

@@ -0,0 +1,10 @@
+namespace FakePieShop.Models
+{
+    public class ShoppingCartItem
+    {
+        public int ShoppingCartItemId { get; set; }
+        public Pie Pie { get; set; } = default!;
+        public int Amount { get; set; }
+        public string? ShoppingCartId { get; set; }
+    }
+}

FakePieShop/Models/ViewModels/ShoppingCartViewModel.cs

@@ -0,0 +1,15 @@
+namespace FakePieShop.Models.ViewModels
+{
+    public class ShoppingCartViewModel
+    {
+        public ShoppingCartViewModel(IShoppingCart shoppingCart, decimal shoppingCartTotal)
+        {
+            ShoppingCart = shoppingCart;
+            ShoppingCartTotal = shoppingCartTotal;
+        }
+
+        public IShoppingCart ShoppingCart { get; }
+
+        public decimal ShoppingCartTotal { get; }
+    }
+}

FakePieShop/Program.cs

@@ -7,7 +7,13 @@ WebApplicationBuilder builder = WebApplication.CreateBuilder(args);
 // add services to application
 builder.Services.AddScoped<IPieRepository, PieRepository>();
 builder.Services.AddScoped<ICategoryRepository, CategoryRepository>();
+builder.Services.AddScoped<IShoppingCart, ShoppingCart>(services => ShoppingCart.GetCart(services));
 
+// include support for sessions and http context
+builder.Services.AddSession();
+builder.Services.AddHttpContextAccessor();
+
+// configuration for MVC and entity framework core
 builder.Services.AddControllersWithViews();
 builder.Services.AddDbContext<FakePieShopDbContext>(options =>
 {
@@ -15,11 +21,11 @@ builder.Services.AddDbContext<FakePieShopDbContext>(options =>
         builder.Configuration["ConnectionStrings:FakePieShopDbContextConnection"]);
 });
 
-WebApplication app = builder.Build();
+var app = builder.Build();
 
 // middlewares
 app.UseStaticFiles();
-//app.UseAuthentication();
+app.UseSession();
 
 // dx and debugging
 if (app.Environment.IsDevelopment())

FakePieShop/Views/Shared/_PieCard.cshtml

@@ -5,6 +5,11 @@
         <img src="@Model.ImageThumbnailUrl" class="card-img-top" alt="@Model.Name">
         <div class="card-body pie-button">
             <h4 class="d-grid">
+                <a class="btn btn-secondary"
+                    asp-controller="ShoppingCart"
+                    asp-action="AddToShoppingCart"
+                    asp-route-pieId="@Model.PieId"> + Add to cart
+                </a>
             </h4>
 
             <div class="d-flex justify-content-between mt-2">

FakePieShop/Views/Shared/_ShoppingCartItemCard.cshtml

@@ -0,0 +1,18 @@
+@model ShoppingCartItem
+
+<div class="card shopping-cart-card mb-2">
+    <div class="row">
+        <div class="col-md-4">
+            <img src="@Model.Pie.ImageThumbnailUrl" class="img-fluid rounded-start p-2" alt="@Model.Pie.Name">
+        </div>
+        <div class="col-md-8">
+            <div class="card-body">
+                <h5 class="card-text">@Model.Amount x @Model.Pie.Name</h5>
+                <div class="d-flex justify-content-between">
+                    <h6>@Model.Pie.ShortDescription</h6>
+                    <h2>@Model.Pie.Price.ToString("c")</h2>
+                </div>
+            </div>
+        </div>
+    </div>
+</div>

FakePieShop/Views/ShoppingCart/Index.cshtml

@@ -0,0 +1,26 @@
+@model ShoppingCartViewModel
+
+<h3 class="my-5">
+    Shopping cart
+</h3>
+
+
+<div class="row gx-3">
+    <div class="col-8">
+        @foreach (var line in Model.ShoppingCart.ShoppingCartItems)
+        {
+            <partial name="_ShoppingCartItemCard" model="line" />
+        }
+    </div>
+    <div class="col-4">
+        <div class="card shopping-cart-card p-3">
+            <div class="row">
+                <h4 class="col">Total:</h4>
+                <h4 class="col text-end">@Model.ShoppingCartTotal.ToString("c")</h4>
+            </div>
+            <hr />
+            <div class="text-center d-grid">
+            </div>
+        </div>
+    </div>
+</div>

FakePieShop/obj/Debug/net6.0/FakePieShop.GeneratedMSBuildEditorConfig.editorconfig

@@ -40,6 +40,14 @@ build_metadata.AdditionalFiles.CssScope =
 build_metadata.AdditionalFiles.TargetPath = Vmlld3NcU2hhcmVkXF9QaWVDYXJkLmNzaHRtbA==
 build_metadata.AdditionalFiles.CssScope = 
 
+[C:/Users/mikay/source/repos/FakePieShop/FakePieShop/Views/Shared/_ShoppingCartItemCard.cshtml]
+build_metadata.AdditionalFiles.TargetPath = Vmlld3NcU2hhcmVkXF9TaG9wcGluZ0NhcnRJdGVtQ2FyZC5jc2h0bWw=
+build_metadata.AdditionalFiles.CssScope = 
+
+[C:/Users/mikay/source/repos/FakePieShop/FakePieShop/Views/ShoppingCart/Index.cshtml]
+build_metadata.AdditionalFiles.TargetPath = Vmlld3NcU2hvcHBpbmdDYXJ0XEluZGV4LmNzaHRtbA==
+build_metadata.AdditionalFiles.CssScope = 
+
 [C:/Users/mikay/source/repos/FakePieShop/FakePieShop/Views/_ViewImports.cshtml]
 build_metadata.AdditionalFiles.TargetPath = Vmlld3NcX1ZpZXdJbXBvcnRzLmNzaHRtbA==
 build_metadata.AdditionalFiles.CssScope = 

FakePieShop/obj/Release/net6.0/FakePieShop.GeneratedMSBuildEditorConfig.editorconfig

@@ -28,10 +28,26 @@ build_metadata.AdditionalFiles.CssScope =
 build_metadata.AdditionalFiles.TargetPath = Vmlld3NcUGllXExpc3QuY3NodG1s
 build_metadata.AdditionalFiles.CssScope = 
 
+[C:/Users/mikay/source/repos/FakePieShop/FakePieShop/Views/Shared/_Carousel.cshtml]
+build_metadata.AdditionalFiles.TargetPath = Vmlld3NcU2hhcmVkXF9DYXJvdXNlbC5jc2h0bWw=
+build_metadata.AdditionalFiles.CssScope = 
+
 [C:/Users/mikay/source/repos/FakePieShop/FakePieShop/Views/Shared/_Layout.cshtml]
 build_metadata.AdditionalFiles.TargetPath = Vmlld3NcU2hhcmVkXF9MYXlvdXQuY3NodG1s
 build_metadata.AdditionalFiles.CssScope = 
 
+[C:/Users/mikay/source/repos/FakePieShop/FakePieShop/Views/Shared/_PieCard.cshtml]
+build_metadata.AdditionalFiles.TargetPath = Vmlld3NcU2hhcmVkXF9QaWVDYXJkLmNzaHRtbA==
+build_metadata.AdditionalFiles.CssScope = 
+
+[C:/Users/mikay/source/repos/FakePieShop/FakePieShop/Views/Shared/_ShoppingCartItemCard.cshtml]
+build_metadata.AdditionalFiles.TargetPath = Vmlld3NcU2hhcmVkXF9TaG9wcGluZ0NhcnRJdGVtQ2FyZC5jc2h0bWw=
+build_metadata.AdditionalFiles.CssScope = 
+
+[C:/Users/mikay/source/repos/FakePieShop/FakePieShop/Views/ShoppingCart/Index.cshtml]
+build_metadata.AdditionalFiles.TargetPath = Vmlld3NcU2hvcHBpbmdDYXJ0XEluZGV4LmNzaHRtbA==
+build_metadata.AdditionalFiles.CssScope = 
+
 [C:/Users/mikay/source/repos/FakePieShop/FakePieShop/Views/_ViewImports.cshtml]
 build_metadata.AdditionalFiles.TargetPath = Vmlld3NcX1ZpZXdJbXBvcnRzLmNzaHRtbA==
 build_metadata.AdditionalFiles.CssScope =