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using System;
using System.Windows.Forms;
using System.Data.SqlClient;

namespace PharmacyDubak
{
    public partial class AuthorizationForm : Form
    {
        private DataBaseConnection _dataBaseConnection;
        private bool _isPasswordShow = false;

        public AuthorizationForm()
        {
            InitializeComponent();
            _dataBaseConnection = new DataBaseConnection();
        }

        private void LoginButton_Click(object sender, EventArgs e)
        {
            string login = LoginTextBox.Text;
            string password = PasswordTextBox.Text;

            if (IsValidUser(login, password))
            {
                MessageBox.Show("Вы успешно вошли!", "Успешно!", MessageBoxButtons.OK, MessageBoxIcon.Information);
                MainForm mainForm = new MainForm();
                mainForm.Show();
                Hide();
            }
            else
            {
                MessageBox.Show("Вы ввели неверно логин или пароль!", "Неудача!", MessageBoxButtons.OK, MessageBoxIcon.Information);
            }
        }

        private bool IsValidUser(string username, string password)
        {
            string query = "IF EXISTS (SELECT * FROM sys.sql_logins WHERE name = @username AND PWDCOMPARE(@password, password_hash) = 1) SELECT 1 ELSE SELECT 0";
            SqlCommand command = new SqlCommand(query, _dataBaseConnection.GetConnection());
            _dataBaseConnection.OpenConnection();
            command.Parameters.AddWithValue("@username", username);
            command.Parameters.AddWithValue("@password", password);
            int result = (int)command.ExecuteScalar();
            return result == 1;
        }

        private void RegistrationLinkClicked(object sender, LinkLabelLinkClickedEventArgs e)
        {
            LoginButton.Enabled = false;
            LoginButton.Visible = false;
            LoginTextBox.Text = "";
            PasswordTextBox.Text = "";
        }

        private void LoginLinkClicked(object sender, LinkLabelLinkClickedEventArgs e)
        {
            LoginButton.Visible = true;
            LoginButton.Enabled = true;
            LoginTextBox.Text = "";
            PasswordTextBox.Text = "";
        }

        private void button1_Click(object sender, EventArgs e)
        {
            if (_isPasswordShow == false)
            {
                PasswordTextBox.PasswordChar = default;
                _isPasswordShow = true;
                Shower.Text = "O";
            }
            else
            {
                PasswordTextBox.PasswordChar = '*';
                _isPasswordShow = false;
                Shower.Text = "Ø";
            }
        }
    }
}