AppCore.Helpers 1.0.7

DatabaseService.Configure(
    "Server=ИМЯ_СЕРВЕРА;Database=toy_shop;User ID=ЛОГИН;Password=ПАРОЛЬ;TrustServerCertificate=True;");

UserSession.cs

    public static class UserSession
    {
        public static int UserId { get; set; }

        public static string Login { get; set; } = string.Empty;

        public static string FullName { get; set; } = "Гость";

        public static string Role { get; set; } = "Гость";

        public static void SetUser(int userId, string login, string fullName, string role)
        {
            UserId = userId;
            Login = login;
            FullName = fullName;
            Role = role;
        }

        public static void SetGuest()
        {
            UserId = 0;
            Login = "guest";
        }

        public static void Clear()
        {
            UserId = 0;
            Login = string.Empty;
            FullName = "Гость";
            Role = "Гость";
        }
    }

AuthService.cs

using AppCore.Helpers;
using Demo_Ex_8.Models;
using System.Data;

namespace Demo_Ex_8.Services
{
    public static class AuthService
    {
        public static bool Login(string login, string password)
        {
            try
            {
                if (!ValidationHelper.ValidateRequiredFields(new()
                {
                    { "Логин", login },
                    { "Пароль", password }
                }))
                {
                    return false;
                }

                string query = """
                    SELECT
                        u.id,
                        u.full_name,
                        u.login,
                        r.role_name
                    FROM users u
                    JOIN roles r ON r.id = u.role_id
                    WHERE u.login = @login
                      AND u.password = @password
                    """;

                DataTable table = DatabaseService.ExecuteSelect(
                    query,
                    new Dictionary<string, object>
                    {
                        { "@login", login },
                        { "@password", password }
                    });

                if (table.Rows.Count == 0)
                {
                    MessageBoxHelper.Warning("Неверный логин или пароль");
                    return false;
                }

                DataRow row = table.Rows[0];

                UserSession.SetUser(
                    Convert.ToInt32(row["id"]),
                    row["login"].ToString(),
                    row["full_name"].ToString(),
                    row["role_name"].ToString());

                return true;
            }
            catch (Exception ex)
            {
                MessageBoxHelper.ShowException(ex);
                return false;
            }
        }

        public static void LoginAsGuest()
        {
            UserSession.SetGuest();
        }

        public static void Logout()
        {
            UserSession.Clear();
        }
    }
}

ProductsService.cs

using AppCore.Helpers;
using System.Data;
using System.Text;

namespace Demo_Ex_8.Services
{
    public static class ProductsService
    {
        public static DataTable GetSuppliers()
        {
            return DatabaseService.ExecuteSelect(
                "SELECT id, supplier_name FROM suppliers ORDER BY supplier_name");
        }

        public static DataTable GetManufacturers()
        {
            return DatabaseService.ExecuteSelect(
                "SELECT id, manufacturer_name FROM manufacturers ORDER BY manufacturer_name");
        }

        public static DataTable GetUnits()
        {
            return DatabaseService.ExecuteSelect(
                "SELECT id, unit_name FROM units ORDER BY unit_name");
        }

        public static DataTable GetCategories()
        {
            return DatabaseService.ExecuteSelect(
                "SELECT id, category_name FROM categories ORDER BY category_name");
        }

        public static DataTable GetProductById(int productId)
        {
            return DatabaseService.ExecuteSelect(
                "SELECT * FROM products WHERE id = @id",
                new Dictionary<string, object>
                {
                    { "@id", productId }
                });
        }

        public static DataTable GetProducts(
            string search = "",
            int supplierId = 0,
            string sortType = "")
        {
            StringBuilder query = new("""
                SELECT
                    p.id,
                    p.article,
                    p.title,
                    u.unit_name,
                    p.price,
                    s.supplier_name,
                    m.manufacturer_name,
                    c.category_name,
                    p.discount,
                    p.quantity,
                    p.description,
                    p.picture_path
                FROM products p
                JOIN units u ON p.unit_id = u.id
                JOIN suppliers s ON p.supplier_id = s.id
                JOIN manufacturers m ON p.manufacturer_id = m.id
                JOIN categories c ON p.category_id = c.id
                WHERE 1 = 1
                """);

            Dictionary<string, object> parameters = new();

            QueryBuilderHelper.AddTextSearch(
                query,
                parameters,
                search,
                "p.title",
                "p.article",
                "p.description",
                "s.supplier_name",
                "m.manufacturer_name",
                "c.category_name");

            QueryBuilderHelper.AddExactFilter(
                query,
                parameters,
                "p.supplier_id",
                "@supplierId",
                supplierId,
                0);

            QueryBuilderHelper.AddOrderBy(
                query,
                sortType,
                new Dictionary<string, string>
                {
                    { "Цена по возрастанию", "p.price ASC" },
                    { "Цена по убыванию", "p.price DESC" },
                    { "Количество по возрастанию", "p.quantity ASC" },
                    { "Количество по убыванию", "p.quantity DESC" },
                    { "Скидка по возрастанию", "p.discount ASC" },
                    { "Скидка по убыванию", "p.discount DESC" },
                    { "Название А-Я", "p.title ASC" },
                    { "Название Я-А", "p.title DESC" }
                },
                "p.id ASC");

            return DatabaseService.ExecuteSelect(query.ToString(), parameters);
        }

        public static bool CreateProduct(
            string article,
            string title,
            int unitId,
            decimal price,
            int supplierId,
            int manufacturerId,
            int categoryId,
            int discount,
            int quantity,
            string description,
            string picturePath)
        {
            string query = """
                INSERT INTO products
                (
                    article,
                    title,
                    unit_id,
                    price,
                    supplier_id,
                    manufacturer_id,
                    category_id,
                    discount,
                    quantity,
                    description,
                    picture_path
                )
                VALUES
                (
                    @article,
                    @title,
                    @unitId,
                    @price,
                    @supplierId,
                    @manufacturerId,
                    @categoryId,
                    @discount,
                    @quantity,
                    @description,
                    @picturePath
                )
                """;

            return DatabaseService.ExecuteNonQuery(
                query,
                new Dictionary<string, object>
                {
                    { "@article", article },
                    { "@title", title },
                    { "@unitId", unitId },
                    { "@price", price },
                    { "@supplierId", supplierId },
                    { "@manufacturerId", manufacturerId },
                    { "@categoryId", categoryId },
                    { "@discount", discount },
                    { "@quantity", quantity },
                    { "@description", description },
                    { "@picturePath", picturePath }
                });
        }

        public static bool UpdateProduct(
            int id,
            string article,
            string title,
            int unitId,
            decimal price,
            int supplierId,
            int manufacturerId,
            int categoryId,
            int discount,
            int quantity,
            string description,
            string picturePath)
        {
            string query = """
                UPDATE products
                SET
                    article = @article,
                    title = @title,
                    unit_id = @unitId,
                    price = @price,
                    supplier_id = @supplierId,
                    manufacturer_id = @manufacturerId,
                    category_id = @categoryId,
                    discount = @discount,
                    quantity = @quantity,
                    description = @description,
                    picture_path = @picturePath
                WHERE id = @id
                """;

            return DatabaseService.ExecuteNonQuery(
                query,
                new Dictionary<string, object>
                {
                    { "@id", id },
                    { "@article", article },
                    { "@title", title },
                    { "@unitId", unitId },
                    { "@price", price },
                    { "@supplierId", supplierId },
                    { "@manufacturerId", manufacturerId },
                    { "@categoryId", categoryId },
                    { "@discount", discount },
                    { "@quantity", quantity },
                    { "@description", description },
                    { "@picturePath", picturePath }
                });
        }

        public static bool DeleteProduct(int id)
        {
            return DatabaseService.ExecuteNonQuery(
                "DELETE FROM products WHERE id = @id",
                new Dictionary<string, object>
                {
                    { "@id", id }
                });
        }

        public static bool ProductExistsInOrders(int productId)
        {
            object? result = DatabaseService.ExecuteScalar(
                """
                SELECT COUNT(*)
                FROM order_items
                WHERE product_id = @productId
                """,
                new Dictionary<string, object>
                {
                    { "@productId", productId }
                });

            return Convert.ToInt32(result) > 0;
        }
    }
}

OrdersService.cs

using AppCore.Helpers;
using System.Data;

namespace Demo_Ex_8.Services
{
    public static class OrdersService
    {
        public static DataTable GetOrders()
        {
            string query = """
                SELECT
                    o.id,
                    o.order_date,
                    o.delivery_date,
                    o.pickup_point_id,
                    o.user_id,
                    o.receipt_code,
                    o.status_id,
                    s.status_name,
                    u.full_name,
                    CONCAT(
                        pp.postal_code,
                        ', г. ',
                        c.city_name,
                        ', ',
                        pp.street,
                        ', ',
                        pp.house
                    ) AS pickup_point
                FROM orders o
                JOIN statuses s ON s.id = o.status_id
                JOIN users u ON u.id = o.user_id
                JOIN pickup_points pp ON pp.id = o.pickup_point_id
                JOIN cities c ON c.id = pp.city_id
                ORDER BY o.id DESC
                """;

            return DatabaseService.ExecuteSelect(query);
        }

        public static DataTable GetOrderById(int orderId)
        {
            string query = """
                SELECT
                    id,
                    order_date,
                    delivery_date,
                    pickup_point_id,
                    user_id,
                    receipt_code,
                    status_id
                FROM orders
                WHERE id = @id
                """;

            return DatabaseService.ExecuteSelect(
                query,
                new Dictionary<string, object>
                {
                    { "@id", orderId }
                });
        }

        public static DataTable GetStatuses()
        {
            return DatabaseService.ExecuteSelect(
                "SELECT id, status_name FROM statuses ORDER BY status_name");
        }

        public static DataTable GetUsers()
        {
            return DatabaseService.ExecuteSelect(
                "SELECT id, full_name FROM users ORDER BY full_name");
        }

        public static DataTable GetPickupPoints()
        {
            string query = """
                SELECT
                    pp.id,
                    CONCAT(
                        pp.postal_code,
                        ', г. ',
                        c.city_name,
                        ', ',
                        pp.street,
                        ', ',
                        pp.house
                    ) AS pickup_point
                FROM pickup_points pp
                JOIN cities c ON c.id = pp.city_id
                ORDER BY pp.id
                """;

            return DatabaseService.ExecuteSelect(query);
        }

        public static bool CreateOrder(
            DateTime orderDate,
            DateTime deliveryDate,
            int pickupPointId,
            int userId,
            string receiptCode,
            int statusId)
        {
            string query = """
                INSERT INTO orders
                (
                    order_date,
                    delivery_date,
                    pickup_point_id,
                    user_id,
                    receipt_code,
                    status_id
                )
                VALUES
                (
                    @orderDate,
                    @deliveryDate,
                    @pickupPointId,
                    @userId,
                    @receiptCode,
                    @statusId
                )
                """;

            return DatabaseService.ExecuteNonQuery(
                query,
                new Dictionary<string, object>
                {
                    { "@orderDate", orderDate },
                    { "@deliveryDate", deliveryDate },
                    { "@pickupPointId", pickupPointId },
                    { "@userId", userId },
                    { "@receiptCode", receiptCode },
                    { "@statusId", statusId }
                });
        }

        public static bool UpdateOrder(
            int id,
            DateTime orderDate,
            DateTime deliveryDate,
            int pickupPointId,
            int userId,
            string receiptCode,
            int statusId)
        {
            string query = """
                UPDATE orders
                SET
                    order_date = @orderDate,
                    delivery_date = @deliveryDate,
                    pickup_point_id = @pickupPointId,
                    user_id = @userId,
                    receipt_code = @receiptCode,
                    status_id = @statusId
                WHERE id = @id
                """;

            return DatabaseService.ExecuteNonQuery(
                query,
                new Dictionary<string, object>
                {
                    { "@id", id },
                    { "@orderDate", orderDate },
                    { "@deliveryDate", deliveryDate },
                    { "@pickupPointId", pickupPointId },
                    { "@userId", userId },
                    { "@receiptCode", receiptCode },
                    { "@statusId", statusId }
                });
        }

        public static bool DeleteOrder(int id)
        {
            string query = """
                DELETE FROM order_items WHERE order_id = @id;
                DELETE FROM orders WHERE id = @id;
                """;

            return DatabaseService.ExecuteNonQuery(
                query,
                new Dictionary<string, object>
                {
                    { "@id", id }
                });
        }
    }
}

ProductCard.cs

	public partial class ProductCard : UserControl
	{
			public int ProductId { get; private set; }

			private readonly int _discountLimit;
			private readonly Color _defaultColor;
			private readonly Color _discountColor;
			private readonly Color _outOfStockColor;

			public event EventHandler<int>? CardClicked;

			public ProductCard(
					DataRow row,
					int discountLimit,
					Color defaultColor,
					Color discountColor,
					Color outOfStockColor)
			{
					InitializeComponent();

					_discountLimit = discountLimit;
					_defaultColor = defaultColor;
					_discountColor = discountColor;
					_outOfStockColor = outOfStockColor;

					FillCard(row);
					AttachClickEvent(this);
			}

			private void ProductCard_Click(object? sender, EventArgs e)
			{
					CardClicked?.Invoke(this, ProductId);
			}

			public void FillCard(DataRow row)
			{
					try
					{
							ProductId = Convert.ToInt32(row["id"]);

							decimal price = Convert.ToDecimal(row["price"]);
							int discount = Convert.ToInt32(row["discount"]);
							int quantity = Convert.ToInt32(row["quantity"]);

							CategoryLabel.Text = row["category_name"].ToString();
							TitleLabel.Text = row["title"].ToString();
							DescriptionLabel.Text = row["description"].ToString();
							ManufacturerLabel.Text = row["manufacturer_name"].ToString();
							SupplierLabel.Text = row["supplier_name"].ToString();
							UnitLabel.Text = row["unit_name"].ToString();
							QuantityLabel.Text = quantity.ToString();
							DiscountLabel.Text = ProductViewHelper.FormatDiscount(discount);

							ProductPicture.Image = ImageHelper.LoadImageOrDefault(
									row["picture_path"].ToString(),
									@"C:Resourse\picture.png");

							ProductPicture.SizeMode = PictureBoxSizeMode.Zoom;

							ProductViewHelper.ApplyProductBackground(
									this,
									quantity,
									discount,
									_discountLimit,
									_defaultColor,
									_discountColor,
									_outOfStockColor);

							ProductViewHelper.ApplyPriceLabels(
									PriceLabel,
									FinalPriceLabel,
									price,
									discount,
									Color.Red,
									Color.Black);
					}
					catch (Exception ex)
					{
							MessageBoxHelper.ShowException(ex);
					}
			}

			private void AttachClickEvent(Control control)
			{
					control.Click -= ProductCard_Click;
					control.Click += ProductCard_Click;

					control.Cursor = Cursors.Hand;

					foreach (Control child in control.Controls)
					{
							AttachClickEvent(child);
					}
			}
	}

OrderCard.cs

	public partial class OrderCard : UserControl
	{
			public int OrderId { get; private set; }

			public event EventHandler<int>? CardClicked;

			public OrderCard(DataRow row)
			{
					InitializeComponent();

					FillCard(row);
					AttachClickEvent(this);
			}

			private void FillCard(DataRow row)
			{
					try
					{
							OrderId = Convert.ToInt32(row["id"]);

							string status = row["status_name"].ToString();
							string pickupPoint = row["pickup_point"].ToString();

							DateTime orderDate = Convert.ToDateTime(row["order_date"]);
							DateTime deliveryDate = Convert.ToDateTime(row["delivery_date"]);

							ArticleLabel.Text = "Артикул заказа: " + OrderId;
							StatusLabel.Text = "Статус заказа: " + status;
							PickupPointLabel.Text = "Адрес пункта выдачи: " + pickupPoint;
							OrderDateLabel.Text = "Дата заказа: " + orderDate.ToString("dd.MM.yyyy");
							DeliveryDateLabel.Text = "Дата доставки: " + deliveryDate.ToString("dd.MM.yyyy");
					}
					catch (Exception ex)
					{
							MessageBoxHelper.ShowException(ex);
					}
			}

			private void AttachClickEvent(Control control)
			{
					control.Click -= OrderCard_Click;
					control.Click += OrderCard_Click;

					control.Cursor = Cursors.Hand;

					foreach (Control child in control.Controls)
					{
							AttachClickEvent(child);
					}
			}

			private void OrderCard_Click(object? sender, EventArgs e)
			{
					CardClicked?.Invoke(this, OrderId);
			}
	}

CatalogForm.cs

	public partial class CatalogForm : Form
	{
			private bool _isLoading = false;

			public CatalogForm()
			{
					InitializeComponent();

					FormHelper.Configure(this, "Каталог", "C:Resourse\\icon.ico");

					LoadData();
			}

			private void LoadData()
			{
					_isLoading = true;

					LoadUserInfo();
					LoadSuppliers();
					LoadSortTypes();

					_isLoading = false;

					LoadProducts();
			}

			private void LoadUserInfo()
			{
					FullNameLabel.Text = UserSession.FullName;
					RoleLabel.Text = UserSession.Role;
			}

			private void LoadSuppliers()
			{
					ComboBoxHelper.LoadWithDefaultItem(
							SupplierComboBox,
							ProductsService.GetSuppliers(),
							"supplier_name",
							"id",
							"Все поставщики");
			}

			private void LoadSortTypes()
			{
					SortComboBox.Items.Clear();

					SortComboBox.Items.Add("По умолчанию");
					SortComboBox.Items.Add("Цена по возрастанию");
					SortComboBox.Items.Add("Цена по убыванию");
					SortComboBox.Items.Add("Количество по возрастанию");
					SortComboBox.Items.Add("Количество по убыванию");
					SortComboBox.Items.Add("Скидка по возрастанию");
					SortComboBox.Items.Add("Скидка по убыванию");
					SortComboBox.Items.Add("Название А-Я");
					SortComboBox.Items.Add("Название Я-А");

					SortComboBox.SelectedIndex = 0;
			}

			private void LoadProducts()
			{
					try
					{
							string search = SearchTextBox.Text.Trim();
							string sortType = SortComboBox.Text;

							int supplierId = 0;

							if (ComboBoxHelper.HasSelectedValue(SupplierComboBox))
							{
									supplierId = ComboBoxHelper.GetSelectedIntValue(SupplierComboBox);
							}

							DataTable table = ProductsService.GetProducts(
									search,
									supplierId,
									sortType);

							CardPanelHelper.Clear(ProductsPanel);

							foreach (DataRow row in table.Rows)
							{
									ProductCard card = new(
											row,
											17,
											Color.White,
											Color.FromArgb(255, 222, 173),
											Color.LightBlue);

									card.CardClicked += Product_Click;

									CardPanelHelper.AddCard(ProductsPanel, card);
							}

							if (!CardPanelHelper.HasCards(ProductsPanel))
							{
									CardPanelHelper.ShowEmptyMessage(
											ProductsPanel,
											"Товары не найдены");
							}
					}
					catch (Exception ex)
					{
							MessageBoxHelper.ShowException(ex);
					}
			}

			private void Product_Click(object? sender, int productId)
			{
					FormHelper.OpenSingleDialog(
							() => new ProductEditForm(productId),
							LoadProducts);
			}

			private void SearchTextBox_TextChanged(object sender, EventArgs e)
			{
					if (_isLoading)
							return;

					LoadProducts();
			}

			private void SupplierComboBox_SelectedIndexChanged(object sender, EventArgs e)
			{
					if (_isLoading)
							return;

					LoadProducts();
			}

			private void SortComboBox_SelectedIndexChanged(object sender, EventArgs e)
			{
					if (_isLoading)
							return;

					LoadProducts();
			}

			private void AddProductBtn_Click(object sender, EventArgs e)
			{
					FormHelper.OpenSingleDialog(
							() => new ProductEditForm(),
							LoadProducts);
			}

			private void OrdersBtn_Click(object sender, EventArgs e)
			{
					FormHelper.OpenSingleDialog(
							() => new OrderForm());
			}

			private void ExitBtn_Click(object sender, EventArgs e)
			{
					AuthService.Logout();
					Close();
			}
	}

CatalogForm.designer

	partial class CatalogForm
	{
			/// <summary>
			/// Required designer variable.
			/// </summary>
			private System.ComponentModel.IContainer components = null;

			/// <summary>
			/// Clean up any resources being used.
			/// </summary>
			/// <param name="disposing">true if managed resources should be disposed; otherwise, false.</param>
			protected override void Dispose(bool disposing)
			{
					if (disposing && (components != null))
					{
							components.Dispose();
					}
					base.Dispose(disposing);
			}

			#region Windows Form Designer generated code

			/// <summary>
			/// Required method for Designer support - do not modify
			/// the contents of this method with the code editor.
			/// </summary>
			private void InitializeComponent()
			{
					System.ComponentModel.ComponentResourceManager resources = new System.ComponentModel.ComponentResourceManager(typeof(CatalogForm));
					RoleLabel = new Label();
					FullNameLabel = new Label();
					SortComboBox = new ComboBox();
					SupplierComboBox = new ComboBox();
					SearchTextBox = new TextBox();
					LogoutBtn = new Button();
					ProductsPanel = new FlowLayoutPanel();
					CreateProductBtn = new Button();
					pictureBox1 = new PictureBox();
					label2 = new Label();
					groupBox1 = new GroupBox();
					label3 = new Label();
					label1 = new Label();
					OrdersForm = new Button();
					((System.ComponentModel.ISupportInitialize)pictureBox1).BeginInit();
					groupBox1.SuspendLayout();
					SuspendLayout();
					//
					// RoleLabel
					//
					RoleLabel.AutoSize = true;
					RoleLabel.Location = new Point(1415, 35);
					RoleLabel.Margin = new Padding(4, 0, 4, 0);
					RoleLabel.Name = "RoleLabel";
					RoleLabel.Size = new Size(49, 21);
					RoleLabel.TabIndex = 1;
					RoleLabel.Text = "Гость";
					//
					// FullNameLabel
					//
					FullNameLabel.AutoSize = true;
					FullNameLabel.Location = new Point(1415, 9);
					FullNameLabel.Margin = new Padding(4, 0, 4, 0);
					FullNameLabel.Name = "FullNameLabel";
					FullNameLabel.Size = new Size(49, 21);
					FullNameLabel.TabIndex = 0;
					FullNameLabel.Text = "Гость";
					//
					// SortComboBox
					//
					SortComboBox.FormattingEnabled = true;
					SortComboBox.Location = new Point(7, 50);
					SortComboBox.Margin = new Padding(4);
					SortComboBox.Name = "SortComboBox";
					SortComboBox.Size = new Size(275, 29);
					SortComboBox.TabIndex = 2;
					SortComboBox.SelectedIndexChanged += SortComboBox_SelectedIndexChanged;
					//
					// SupplierComboBox
					//
					SupplierComboBox.FormattingEnabled = true;
					SupplierComboBox.Location = new Point(7, 123);
					SupplierComboBox.Margin = new Padding(4);
					SupplierComboBox.Name = "SupplierComboBox";
					SupplierComboBox.Size = new Size(275, 29);
					SupplierComboBox.TabIndex = 1;
					SupplierComboBox.SelectedIndexChanged += SupplierComboBox_SelectedIndexChanged;
					//
					// SearchTextBox
					//
					SearchTextBox.Location = new Point(645, 21);
					SearchTextBox.Margin = new Padding(4);
					SearchTextBox.Name = "SearchTextBox";
					SearchTextBox.PlaceholderText = "Поиск товаров по названию, поставщику, ";
					SearchTextBox.Size = new Size(709, 29);
					SearchTextBox.TabIndex = 0;
					SearchTextBox.TextChanged += SearchTextBox_TextChanged;
					//
					// LogoutBtn
					//
					LogoutBtn.Location = new Point(1697, 13);
					LogoutBtn.Margin = new Padding(4);
					LogoutBtn.Name = "LogoutBtn";
					LogoutBtn.Size = new Size(96, 43);
					LogoutBtn.TabIndex = 3;
					LogoutBtn.Text = "Выход";
					LogoutBtn.UseVisualStyleBackColor = true;
					LogoutBtn.Click += ExitBtn_Click;
					//
					// ProductsPanel
					//
					ProductsPanel.AutoScroll = true;
					ProductsPanel.Location = new Point(311, 115);
					ProductsPanel.Margin = new Padding(4);
					ProductsPanel.Name = "ProductsPanel";
					ProductsPanel.Size = new Size(1491, 881);
					ProductsPanel.TabIndex = 4;
					//
					// CreateProductBtn
					//
					CreateProductBtn.Location = new Point(7, 218);
					CreateProductBtn.Margin = new Padding(4);
					CreateProductBtn.Name = "CreateProductBtn";
					CreateProductBtn.Size = new Size(275, 41);
					CreateProductBtn.TabIndex = 5;
					CreateProductBtn.Text = "Добавить товар";
					CreateProductBtn.UseVisualStyleBackColor = true;
					CreateProductBtn.Click += AddProductBtn_Click;
					//
					// pictureBox1
					//
					pictureBox1.Image = (Image)resources.GetObject("pictureBox1.Image");
					pictureBox1.Location = new Point(13, 9);
					pictureBox1.Margin = new Padding(4);
					pictureBox1.Name = "pictureBox1";
					pictureBox1.Size = new Size(102, 99);
					pictureBox1.SizeMode = PictureBoxSizeMode.Zoom;
					pictureBox1.TabIndex = 6;
					pictureBox1.TabStop = false;
					//
					// label2
					//
					label2.AutoSize = true;
					label2.Font = new Font("Segoe UI", 15.75F, FontStyle.Regular, GraphicsUnit.Point, 204);
					label2.Location = new Point(123, 9);
					label2.Margin = new Padding(4, 0, 4, 0);
					label2.Name = "label2";
					label2.Size = new Size(171, 30);
					label2.TabIndex = 7;
					label2.Text = "Каталог товаров";
					//
					// groupBox1
					//
					groupBox1.Controls.Add(label3);
					groupBox1.Controls.Add(label1);
					groupBox1.Controls.Add(SortComboBox);
					groupBox1.Controls.Add(SupplierComboBox);
					groupBox1.Controls.Add(CreateProductBtn);
					groupBox1.Location = new Point(12, 115);
					groupBox1.Name = "groupBox1";
					groupBox1.Size = new Size(292, 268);
					groupBox1.TabIndex = 8;
					groupBox1.TabStop = false;
					//
					// label3
					//
					label3.AutoSize = true;
					label3.Font = new Font("Segoe UI", 12F, FontStyle.Regular, GraphicsUnit.Point, 204);
					label3.Location = new Point(7, 98);
					label3.Margin = new Padding(4, 0, 4, 0);
					label3.Name = "label3";
					label3.Size = new Size(90, 21);
					label3.TabIndex = 10;
					label3.Text = "Поставщик";
					//
					// label1
					//
					label1.AutoSize = true;
					label1.Font = new Font("Segoe UI", 12F, FontStyle.Regular, GraphicsUnit.Point, 204);
					label1.Location = new Point(7, 25);
					label1.Margin = new Padding(4, 0, 4, 0);
					label1.Name = "label1";
					label1.Size = new Size(96, 21);
					label1.TabIndex = 9;
					label1.Text = "Сортировка";
					//
					// OrdersForm
					//
					OrdersForm.Location = new Point(12, 956);
					OrdersForm.Margin = new Padding(4);
					OrdersForm.Name = "OrdersForm";
					OrdersForm.Size = new Size(184, 33);
					OrdersForm.TabIndex = 11;
					OrdersForm.Text = "Форма с заказами";
					OrdersForm.UseVisualStyleBackColor = true;
					OrdersForm.Click += OrdersBtn_Click;
					//
					// CatalogForm
					//
					AutoScaleDimensions = new SizeF(9F, 21F);
					AutoScaleMode = AutoScaleMode.Font;
					ClientSize = new Size(1815, 1002);
					Controls.Add(OrdersForm);
					Controls.Add(groupBox1);
					Controls.Add(label2);
					Controls.Add(RoleLabel);
					Controls.Add(FullNameLabel);
					Controls.Add(pictureBox1);
					Controls.Add(ProductsPanel);
					Controls.Add(SearchTextBox);
					Controls.Add(LogoutBtn);
					Font = new Font("Segoe UI", 12F, FontStyle.Regular, GraphicsUnit.Point, 204);
					Icon = (Icon)resources.GetObject("$this.Icon");
					Margin = new Padding(4);
					Name = "CatalogForm";
					Text = "CatalogForm";
					((System.ComponentModel.ISupportInitialize)pictureBox1).EndInit();
					groupBox1.ResumeLayout(false);
					groupBox1.PerformLayout();
					ResumeLayout(false);
					PerformLayout();
			}

			#endregion
			private Label RoleLabel;
			private Label FullNameLabel;
			private TextBox SearchTextBox;
			private Button LogoutBtn;
			private ComboBox SupplierComboBox;
			private ComboBox SortComboBox;
			private FlowLayoutPanel ProductsPanel;
			private Button CreateProductBtn;
			private PictureBox pictureBox1;
			private Label label2;
			private GroupBox groupBox1;
			private Label label3;
			private Label label1;
			private Button OrdersForm;
	}

LoginForm.cs

public partial class Login : Form
{
    public Login()
    {
        InitializeComponent();
        FormHelper.Configure(this, "Форма входа", "C:Resourse\\icon.ico");
    }

    private void loginBtn_Click(object sender, EventArgs e)
    {
        bool isLoginSuccess = AuthService.Login(LoginTextBox.Text, PasswordTextBox.Text);

        if (!isLoginSuccess)
        {
            return;
        }

        OpenCatalogForm();
    }

    private void loginAsGuestBtn_Click(object sender, EventArgs e)
    {
        AuthService.LoginAsGuest();

        OpenCatalogForm();
    }

    public void OpenCatalogForm()
    {
        FormHelper.HideCurrentAndOpen(this, new CatalogForm());
    }
}

ProductEditForm.cs

using AppCore.Helpers;
using Demo_Ex_8.Services;
using System.Data;

namespace Demo_Ex_8.Forms
{

    public partial class ProductEditForm : Form
    {
        private readonly int? _productId;

        private string _picturePath = string.Empty;

        private const string DefaultPicturePath =
            @"C:Resourse\picture.png";

        private const string IconPath =
            @"C:Resourse\icon.ico";

        public bool IsSaved { get; private set; }

        public ProductEditForm()
        {
            FormHelper.Configure(this, "Создание товара", IconPath);
            InitializeComponent();


            ConfigureCreateMode();
        }

        public ProductEditForm(int productId)
        {
            InitializeComponent();

            _productId = productId;

            FormHelper.Configure(this, "Редактирование товара", IconPath);

            ConfigureEditMode();
        }

        private void ProductEditForm_Load(object sender, EventArgs e)
        {
            LoadComboBoxes();

            if (_productId.HasValue)
            {
                LoadProductData(_productId.Value);
            }
            else
            {
                ProductPictureBox.Image = ImageHelper.LoadImageOrDefault(
                    string.Empty,
                    DefaultPicturePath);
            }
        }

        private void ConfigureCreateMode()
        {
            CreateBtn.Visible = true;
            SaveBtn.Visible = false;
            DeleteBtn.Visible = false;
        }

        private void ConfigureEditMode()
        {
            CreateBtn.Visible = false;
            SaveBtn.Visible = true;
            DeleteBtn.Visible = true;
        }

        private void LoadComboBoxes()
        {
            ComboBoxHelper.Load(
                UnitComboBox,
                ProductsService.GetUnits(),
                "unit_name",
                "id");

            ComboBoxHelper.Load(
                SupplierComboBox,
                ProductsService.GetSuppliers(),
                "supplier_name",
                "id");

            ComboBoxHelper.Load(
                ManufacturerComboBox,
                ProductsService.GetManufacturers(),
                "manufacturer_name",
                "id");

            ComboBoxHelper.Load(
                CategoryComboBox,
                ProductsService.GetCategories(),
                "category_name",
                "id");
        }

        private void LoadProductData(int productId)
        {
            DataTable table = ProductsService.GetProductById(productId);

            if (table.Rows.Count == 0)
            {
                MessageBoxHelper.Warning("Товар не найден");
                Close();
                return;
            }

            DataRow row = table.Rows[0];

            ArticleTextBox.Text = row["article"].ToString();
            TitleTextBox.Text = row["title"].ToString();
            PriceTextBox.Text = row["price"].ToString();
            QuantityTextBox.Text = row["quantity"].ToString();
            DiscountTextBox.Text = row["discount"].ToString();
            DescriptionTextBox.Text = row["description"].ToString();

            UnitComboBox.SelectedValue = Convert.ToInt32(row["unit_id"]);
            SupplierComboBox.SelectedValue = Convert.ToInt32(row["supplier_id"]);
            ManufacturerComboBox.SelectedValue = Convert.ToInt32(row["manufacturer_id"]);
            CategoryComboBox.SelectedValue = Convert.ToInt32(row["category_id"]);

            _picturePath = row["picture_path"].ToString();

            ProductPictureBox.Image = ImageHelper.LoadImageOrDefault(
                _picturePath,
                DefaultPicturePath);
        }

        private bool ValidateForm(
            out decimal price,
            out int quantity,
            out int discount)
        {
            price = 0;
            quantity = 0;
            discount = 0;

            if (!ValidationHelper.ValidateRequiredFields(new()
            {
                { "Артикул", ArticleTextBox.Text },
                { "Название", TitleTextBox.Text },
                { "Цена", PriceTextBox.Text },
                { "Количество на складе", QuantityTextBox.Text },
                { "Скидка", DiscountTextBox.Text },
                { "Описание", DescriptionTextBox.Text }
            }))
            {
                return false;
            }

            if (!ValidationHelper.TryGetDecimal(PriceTextBox.Text, "Цена", out price))
            {
                return false;
            }

            if (price < 0)
            {
                MessageBoxHelper.Warning("Цена не может быть меньше нуля");
                return false;
            }

            if (!ValidationHelper.TryGetInt(QuantityTextBox.Text, "Количество на складе", out quantity))
            {
                return false;
            }

            if (quantity < 0)
            {
                MessageBoxHelper.Warning("Количество на складе не может быть меньше нуля");
                return false;
            }

            if (!ValidationHelper.TryGetInt(DiscountTextBox.Text, "Скидка", out discount))
            {
                return false;
            }

            if (discount < 0 || discount > 100)
            {
                MessageBoxHelper.Warning("Скидка должна быть от 0 до 100");
                return false;
            }

            if (!ValidationHelper.ValidateComboBoxSelected(UnitComboBox, "Единица измерения"))
            {
                return false;
            }

            if (!ValidationHelper.ValidateComboBoxSelected(SupplierComboBox, "Поставщик"))
            {
                return false;
            }

            if (!ValidationHelper.ValidateComboBoxSelected(ManufacturerComboBox, "Производитель"))
            {
                return false;
            }

            if (!ValidationHelper.ValidateComboBoxSelected(CategoryComboBox, "Категория"))
            {
                return false;
            }

            return true;
        }

        private void CreateBtn_Click(object sender, EventArgs e)
        {
            if (!ValidateForm(out decimal price, out int quantity, out int discount))
            {
                return;
            }

            bool result = ProductsService.CreateProduct(
                ArticleTextBox.Text.Trim(),
                TitleTextBox.Text.Trim(),
                ComboBoxHelper.GetSelectedIntValue(UnitComboBox),
                price,
                ComboBoxHelper.GetSelectedIntValue(SupplierComboBox),
                ComboBoxHelper.GetSelectedIntValue(ManufacturerComboBox),
                ComboBoxHelper.GetSelectedIntValue(CategoryComboBox),
                discount,
                quantity,
                DescriptionTextBox.Text.Trim(),
                _picturePath);

            if (result)
            {
                IsSaved = true;
                MessageBoxHelper.Info("Товар успешно создан");
                Close();
            }
        }

        private void SaveBtn_Click(object sender, EventArgs e)
        {
            if (!_productId.HasValue)
            {
                MessageBoxHelper.Warning("Не выбран товар для редактирования");
                return;
            }

            if (!ValidateForm(out decimal price, out int quantity, out int discount))
            {
                return;
            }

            bool result = ProductsService.UpdateProduct(
                _productId.Value,
                ArticleTextBox.Text.Trim(),
                TitleTextBox.Text.Trim(),
                ComboBoxHelper.GetSelectedIntValue(UnitComboBox),
                price,
                ComboBoxHelper.GetSelectedIntValue(SupplierComboBox),
                ComboBoxHelper.GetSelectedIntValue(ManufacturerComboBox),
                ComboBoxHelper.GetSelectedIntValue(CategoryComboBox),
                discount,
                quantity,
                DescriptionTextBox.Text.Trim(),
                _picturePath);

            if (result)
            {
                IsSaved = true;
                MessageBoxHelper.Info("Товар успешно сохранён");
                Close();
            }
        }

        private void DeleteBtn_Click(object sender, EventArgs e)
        {
            if (!_productId.HasValue)
            {
                MessageBoxHelper.Warning("Не выбран товар для удаления");
                return;
            }

            if (!MessageBoxHelper.Confirm("Удалить выбранный товар?"))
            {
                return;
            }

            if (ProductsService.ProductExistsInOrders(_productId.Value))
            {
                MessageBoxHelper.Warning("Нельзя удалить товар, который присутствует в заказе");
                return;
            }

            bool result = ProductsService.DeleteProduct(_productId.Value);

            if (result)
            {
                IsSaved = true;
                MessageBoxHelper.Info("Товар успешно удалён");
                Close();
            }
        }

        private void ProductPictureBox_Click(object sender, EventArgs e)
        {
            string selectedPath = ImageHelper.SelectImageFile();

            if (string.IsNullOrWhiteSpace(selectedPath))
            {
                return;
            }

            _picturePath = selectedPath;

            ProductPictureBox.Image = ImageHelper.LoadImageOrDefault(
                _picturePath,
                DefaultPicturePath);

            ProductPictureBox.SizeMode = PictureBoxSizeMode.Zoom;
        }
    }
}

OrdersForm.cs

using AppCore.Helpers;
using Demo_Ex_8.Cards;
using Demo_Ex_8.Services;
using System.Data;

namespace Demo_Ex_8.Forms
{
    public partial class OrderForm : Form
    {
        private const string IconPath =
            @"C:Resourse\icon.ico";

        public OrderForm()
        {
            InitializeComponent();

            FormHelper.Configure(this, "Заказы", IconPath);

            LoadOrders();
        }

        private void LoadOrders()
        {
            DataTable table = OrdersService.GetOrders();

            CardPanelHelper.Clear(OrdersPanel);

            foreach (DataRow row in table.Rows)
            {
                OrderCard card = new(row);

                card.Width = OrdersPanel.Width - 25;
                card.CardClicked += OrderCard_Click;

                CardPanelHelper.AddCard(OrdersPanel, card);
            }

            if (!CardPanelHelper.HasCards(OrdersPanel))
            {
                CardPanelHelper.ShowEmptyMessage(
                    OrdersPanel,
                    "Заказы не найдены");
            }
        }

        private void OrderCard_Click(object? sender, int orderId)
        {
            FormHelper.OpenSingleDialog(
                () => new OrderEditForm(orderId),
                LoadOrders);
        }

        private void AddOrderBtn_Click(object sender, EventArgs e)
        {
            FormHelper.OpenSingleDialog(
                () => new OrderEditForm(),
                LoadOrders);
        }
    }
}

OrderEditForm.cs

using AppCore.Helpers;
using Demo_Ex_8.Services;
using System.Data;

namespace Demo_Ex_8.Forms
{
    public partial class OrderEditForm : Form
    {
        private readonly int? _orderId;

        private const string IconPath =
            @"C:Resourse\icon.ico";

        public bool IsSaved { get; private set; }

        public OrderEditForm()
        {
            InitializeComponent();

            FormHelper.Configure(this, "Создание заказа", IconPath);

            ConfigureCreateMode();
            LoadComboBoxes();
        }

        public OrderEditForm(int orderId)
        {
            InitializeComponent();

            _orderId = orderId;

            FormHelper.Configure(this, "Редактирование заказа", IconPath);

            ConfigureEditMode();
            LoadComboBoxes();
            LoadOrderData(orderId);
        }

        private void ConfigureCreateMode()
        {
            OrderNumber.Text = "Новый";

            CreateBtn.Visible = true;
            SaveBtn.Visible = false;
            DeleteBtn.Visible = false;

            OrderDate.Value = DateTime.Today;
            DeliveryDate.Value = DateTime.Today;
        }

        private void ConfigureEditMode()
        {
            CreateBtn.Visible = false;
            SaveBtn.Visible = true;
            DeleteBtn.Visible = true;
        }

        private void LoadComboBoxes()
        {
            ComboBoxHelper.Load(
                StatusComboBox,
                OrdersService.GetStatuses(),
                "status_name",
                "id");

            ComboBoxHelper.Load(
                PickupPointAddressComboBox,
                OrdersService.GetPickupPoints(),
                "pickup_point",
                "id");

            ComboBoxHelper.Load(
                UserComboBox,
                OrdersService.GetUsers(),
                "full_name",
                "id");
        }

        private void LoadOrderData(int orderId)
        {
            DataTable table = OrdersService.GetOrderById(orderId);

            if (table.Rows.Count == 0)
            {
                MessageBoxHelper.Warning("Заказ не найден");
                Close();
                return;
            }

            DataRow row = table.Rows[0];

            OrderNumber.Text = row["id"].ToString();

            OrderDate.Value = Convert.ToDateTime(row["order_date"]);
            DeliveryDate.Value = Convert.ToDateTime(row["delivery_date"]);

            ReceiptCode.Text = row["receipt_code"].ToString();

            PickupPointAddressComboBox.SelectedValue = Convert.ToInt32(row["pickup_point_id"]);
            UserComboBox.SelectedValue = Convert.ToInt32(row["user_id"]);
            StatusComboBox.SelectedValue = Convert.ToInt32(row["status_id"]);
        }

        private bool ValidateForm()
        {
            if (!ValidationHelper.ValidateRequiredField(ReceiptCode.Text, "Код получения"))
            {
                return false;
            }

            if (!ValidationHelper.ValidateComboBoxSelected(StatusComboBox, "Статус заказа"))
            {
                return false;
            }

            if (!ValidationHelper.ValidateComboBoxSelected(PickupPointAddressComboBox, "Адрес пункта выдачи"))
            {
                return false;
            }

            if (!ValidationHelper.ValidateComboBoxSelected(UserComboBox, "Пользователь"))
            {
                return false;
            }

            if (!ValidationHelper.ValidateDateRange(
                OrderDate.Value.Date,
                DeliveryDate.Value.Date))
            {
                return false;
            }

            return true;
        }

        private void CreateBtn_Click(object sender, EventArgs e)
        {
            if (!ValidateForm())
            {
                return;
            }

            bool result = OrdersService.CreateOrder(
                OrderDate.Value.Date,
                DeliveryDate.Value.Date,
                ComboBoxHelper.GetSelectedIntValue(PickupPointAddressComboBox),
                ComboBoxHelper.GetSelectedIntValue(UserComboBox),
                ReceiptCode.Text.Trim(),
                ComboBoxHelper.GetSelectedIntValue(StatusComboBox));

            if (result)
            {
                IsSaved = true;
                MessageBoxHelper.Info("Заказ успешно создан");
                Close();
            }
        }

        private void SaveBtn_Click(object sender, EventArgs e)
        {
            if (!_orderId.HasValue)
            {
                MessageBoxHelper.Warning("Не выбран заказ для редактирования");
                return;
            }

            if (!ValidateForm())
            {
                return;
            }

            bool result = OrdersService.UpdateOrder(
                _orderId.Value,
                OrderDate.Value.Date,
                DeliveryDate.Value.Date,
                ComboBoxHelper.GetSelectedIntValue(PickupPointAddressComboBox),
                ComboBoxHelper.GetSelectedIntValue(UserComboBox),
                ReceiptCode.Text.Trim(),
                ComboBoxHelper.GetSelectedIntValue(StatusComboBox));

            if (result)
            {
                IsSaved = true;
                MessageBoxHelper.Info("Заказ успешно сохранён");
                Close();
            }
        }

        private void DeleteBtn_Click(object sender, EventArgs e)
        {
            if (!_orderId.HasValue)
            {
                MessageBoxHelper.Warning("Не выбран заказ для удаления");
                return;
            }

            if (!MessageBoxHelper.Confirm("Удалить выбранный заказ?"))
            {
                return;
            }

            bool result = OrdersService.DeleteOrder(_orderId.Value);

            if (result)
            {
                IsSaved = true;
                MessageBoxHelper.Info("Заказ успешно удалён");
                Close();
            }
        }
    }
}