using System;
using System.Collections;
using System.Configuration;
using System.Data;
using System.Linq;
using System.Web;
using System.Web.Security;
using System.Web.UI;
using System.Web.UI.HtmlControls;
using System.Web.UI.WebControls;
using System.Web.UI.WebControls.WebParts;
using System.Xml.Linq;

using System.Data.SqlClient;
using System.Web.Configuration;

public partial class Lec12_Sessions_and_Cookies_UsingSessions : System.Web.UI.Page
{
    protected void Page_Load(object sender, EventArgs e)
    {
        if (Session["LoggedIn"] != null)
        {
            LoggedIn();
        }
        else
        {
            LoggedOut();
        }
    }

    protected void loginButton_Click(object sender, EventArgs e)
    {
        SqlConnection connection;
        SqlCommand command;
        SqlDataReader reader;

        try
        {
            // Connect to the database using the connection string in the web.config file
            connection = new SqlConnection(WebConfigurationManager.ConnectionStrings["DatabaseConnectionString"].ConnectionString);

            // Create an SELECT Sql statement
            command = new SqlCommand("SELECT * FROM Users WHERE Username=@Username AND Password=@Password", connection);
            command.Parameters.AddWithValue("@Username", userTextBox.Text);
            command.Parameters.AddWithValue("@Password", passwordTextBox.Text);

            using (connection)
            {
                // Open the connection
                connection.Open();

                // Execute the command, the records are returned in an SqlDataReader object
                reader = command.ExecuteReader();

                // Have a row been returned?
                if (reader.HasRows)
                {
                    // Logged in OK
                    reader.Read();
                    Session["LoggedIn"] = reader["FullName"];
                    Session.Timeout = 40;   // 40 minutes
                    LoggedIn();
                }
                else
                {
                    // No match found
                }

                // Close the connection
                connection.Close();
            }
        }
        catch
        {
            // Some error occurred
        }

    }

    protected void logoutButton_Click(object sender, EventArgs e)
    {
        Session.Clear();
        Session.Abandon();
        LoggedOut();
    }

    private void LoggedIn()
    {
        welcomeLabel.Text = "Hi " + Session["LoggedIn"];
        loginPanel.Visible = false;
        logoutPanel.Visible = true;
    }

    private void LoggedOut()
    {
        loginPanel.Visible = true;
        logoutPanel.Visible = false;
    }
}