using MySql.Data.MySqlClient;
using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows.Forms;
using static System.Windows.Forms.VisualStyles.VisualStyleElement.TextBox;

namespace NeshinaPolina07_11
{
    public partial class AddProduct : Form
    {
        private _1Menu parentForm;

        public AddProduct(_1Menu parent)
        {
            InitializeComponent();
            parentForm = parent;
            LoadCategories();
            LoadManufacturers();
            LoadSuppliers();
        }

        private void LoadCategories()
        {
            cmbCategory.Items.Clear();
            try
            {
                var db = DB.GetInstance();
                var connection = db.GetConnection();
                string query = "SELECT category_id, category_name FROM categories ORDER BY category_name";
                using (MySqlCommand cmd = new MySqlCommand(query, connection))
                using (MySqlDataReader reader = cmd.ExecuteReader())
                {
                    while (reader.Read())
                    {
                        cmbCategory.Items.Add(new CategoryItem
                        {
                            Id = Convert.ToInt32(reader["category_id"]),
                            Name = reader["category_name"].ToString()
                        });
                    }
                }
            }
            catch (Exception ex)
            {
                MessageBox.Show("Ошибка загрузки категорий: " + ex.Message, "Ошибка", MessageBoxButtons.OK, MessageBoxIcon.Error);
            }
            cmbCategory.DisplayMember = "Name";
            cmbCategory.ValueMember = "Id";
            if (cmbCategory.Items.Count > 0) cmbCategory.SelectedIndex = 0;
        }

        private void LoadManufacturers()
        {
            cmbManufacturer.Items.Clear();
            try
            {
                var db = DB.GetInstance();
                var connection = db.GetConnection();
                string query = "SELECT manufacturer_id, manufacturer_name FROM manufacturers ORDER BY manufacturer_name";
                using (MySqlCommand cmd = new MySqlCommand(query, connection))
                using (MySqlDataReader reader = cmd.ExecuteReader())
                {
                    while (reader.Read())
                    {
                        cmbManufacturer.Items.Add(new ManufacturerItem
                        {
                            Id = Convert.ToInt32(reader["manufacturer_id"]),
                            Name = reader["manufacturer_name"].ToString()
                        });
                    }
                }
            }
            catch (Exception ex)
            {
                MessageBox.Show("Ошибка загрузки производителей: " + ex.Message, "Ошибка", MessageBoxButtons.OK, MessageBoxIcon.Error);
            }
            cmbManufacturer.DisplayMember = "Name";
            cmbManufacturer.ValueMember = "Id";
            if (cmbManufacturer.Items.Count > 0) cmbManufacturer.SelectedIndex = 0;
        }

        private void LoadSuppliers()
        {
            cmbSupplier.Items.Clear();
            try
            {
                var db = DB.GetInstance();
                var connection = db.GetConnection();
                string query = "SELECT supplier_id, supplier_name FROM suppliers ORDER BY supplier_name";
                using (MySqlCommand cmd = new MySqlCommand(query, connection))
                using (MySqlDataReader reader = cmd.ExecuteReader())
                {
                    while (reader.Read())
                    {
                        cmbSupplier.Items.Add(new SupplierItem
                        {
                            Id = Convert.ToInt32(reader["supplier_id"]),
                            Name = reader["supplier_name"].ToString()
                        });
                    }
                }
            }
            catch (Exception ex)
            {
                MessageBox.Show("Ошибка загрузки поставщиков: " + ex.Message, "Ошибка", MessageBoxButtons.OK, MessageBoxIcon.Error);
            }
            cmbSupplier.DisplayMember = "Name";
            cmbSupplier.ValueMember = "Id";
            if (cmbSupplier.Items.Count > 0) cmbSupplier.SelectedIndex = 0;
        }

        private class CategoryItem
        {
            public int Id { get; set; }
            public string Name { get; set; }
            public override string ToString() => Name;
        }

        private class ManufacturerItem
        {
            public int Id { get; set; }
            public string Name { get; set; }
            public override string ToString() => Name;
        }

        private class SupplierItem
        {
            public int Id { get; set; }
            public string Name { get; set; }
            public override string ToString() => Name;
        }

        private int? GetCategoryId() => cmbCategory.SelectedItem is CategoryItem c ? c.Id : (int?)null;
        private int? GetManufacturerId() => cmbManufacturer.SelectedItem is ManufacturerItem m ? m.Id : (int?)null;
        private int? GetSupplierId() => cmbSupplier.SelectedItem is SupplierItem s ? s.Id : (int?)null;


        private void textBox5_TextChanged(object sender, EventArgs e)
        {

        }

        private void button1_Click(object sender, EventArgs e)
        {
            if (string.IsNullOrWhiteSpace(txtArticle.Text) || string.IsNullOrWhiteSpace(txtName.Text))
            {
                MessageBox.Show("Артикул и название товара обязательны для заполнения.", "Ошибка", MessageBoxButtons.OK, MessageBoxIcon.Warning);
                return;
            }

            if (!string.IsNullOrWhiteSpace(txtPrice.Text))
            {
                if (!decimal.TryParse(txtPrice.Text.Replace(',', '.'), out decimal price) || price < 0)
                {
                    MessageBox.Show("Цена должна быть положительным числом (например: 199.99).", "Некорректная цена", MessageBoxButtons.OK, MessageBoxIcon.Warning);
                    txtPrice.Focus();
                    return;
                }
            }

            if (!string.IsNullOrWhiteSpace(txtDiscount.Text))
            {
                if (!int.TryParse(txtDiscount.Text, out int discount) || discount < 0 || discount > 100)
                {
                    MessageBox.Show("Скидка должна быть целым числом от 0 до 100%.", "Некорректная скидка", MessageBoxButtons.OK, MessageBoxIcon.Warning);
                    txtDiscount.Focus();
                    return;
                }
            }

            if (!string.IsNullOrWhiteSpace(txtQuantity.Text))
            {
                if (!int.TryParse(txtQuantity.Text, out int quantity) || quantity < 0)
                {
                    MessageBox.Show("Количество должно быть целым неотрицательным числом (0 или больше).", "Некорректное количество", MessageBoxButtons.OK, MessageBoxIcon.Warning);
                    txtQuantity.Focus();
                    return;
                }
            }

            try
            {
                var db = DB.GetInstance();
                var connection = db.GetConnection();

                string query = @"
            INSERT INTO products (
                product_article, product_name, unit, price, discount, quantity_in_stock, description,
                category_id, manufacturer_id, supplier_id
            ) VALUES (
                @article, @name, 'шт.', @price, @discount, @quantity, @description,
                @categoryId, @manufacturerId, @supplierId
            )";

                using (MySqlCommand cmd = new MySqlCommand(query, connection))
                {
                    cmd.Parameters.AddWithValue("@article", txtArticle.Text.Trim());
                    cmd.Parameters.AddWithValue("@name", txtName.Text.Trim());

                    if (decimal.TryParse(txtPrice.Text.Replace(',', '.'), out decimal parsedPrice))
                        cmd.Parameters.AddWithValue("@price", parsedPrice);
                    else
                        cmd.Parameters.AddWithValue("@price", DBNull.Value);

                    if (int.TryParse(txtDiscount.Text, out int parsedDiscount))
                        cmd.Parameters.AddWithValue("@discount", parsedDiscount);
                    else
                        cmd.Parameters.AddWithValue("@discount", DBNull.Value);

                    if (int.TryParse(txtQuantity.Text, out int parsedQuantity))
                        cmd.Parameters.AddWithValue("@quantity", parsedQuantity);
                    else
                        cmd.Parameters.AddWithValue("@quantity", DBNull.Value);

                    cmd.Parameters.AddWithValue("@description", string.IsNullOrWhiteSpace(txtDescription.Text)
                        ? (object)DBNull.Value
                        : txtDescription.Text.Trim());

                    cmd.Parameters.AddWithValue("@categoryId", GetCategoryId() ?? (object)DBNull.Value);
                    cmd.Parameters.AddWithValue("@manufacturerId", GetManufacturerId() ?? (object)DBNull.Value);
                    cmd.Parameters.AddWithValue("@supplierId", GetSupplierId() ?? (object)DBNull.Value);

                    if (cmd.ExecuteNonQuery() > 0)
                    {
                        MessageBox.Show("Товар успешно добавлен!", "Успех", MessageBoxButtons.OK, MessageBoxIcon.Information);
                        parentForm.RefreshData();
                        this.Close();
                    }
                    else
                    {
                        MessageBox.Show("Не удалось добавить товар.", "Ошибка", MessageBoxButtons.OK, MessageBoxIcon.Error);
                    }
                }
            }
            catch (Exception ex)
            {
                MessageBox.Show("Ошибка при добавлении товара: " + ex.Message, "Ошибка", MessageBoxButtons.OK, MessageBoxIcon.Error);
            }
        }
    }
}