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 System.Data.SqlClient;
using System.Configuration;

namespace LibraryManagementSystem
{
    public partial class login : Form
    {
        // variables
        SqlConnection con;
        SqlCommand cmd;

        // userid and pwd
        public static int userid;
        public static string password;

        private void login_Load(object sender, EventArgs e)
        {
            // initialise connection to db
            string connectionString = ConfigurationManager.ConnectionStrings["LibraryManagementSystem.Properties.Settings.LibraryDB"].ToString();
            con = new SqlConnection(connectionString);
        }

        public login()
        {
            InitializeComponent();
        }

        // functions to empty text boxes on login
        public void clear()
        {
            loginTbxUserId.Text = string.Empty;
            loginTbxPassword.Text = string.Empty;
        }

        private void LoginBtnSubmit_Click(object sender, EventArgs e)
        {
            if (con.State == ConnectionState.Closed)
                con.Open();

            cmd = new SqlCommand("select * from users where user_id = @user_id and password = @password", con);
            cmd.Parameters.AddWithValue("@user_id", loginTbxUserId.Text);
            cmd.Parameters.AddWithValue("@password", loginTbxPassword.Text);

            SqlDataAdapter sda = new SqlDataAdapter(cmd);
            DataTable dt = new DataTable();

            sda.Fill(dt);

            if (dt.Rows.Count > 0)
            {
                // successfully logged in pass userid and pwd
                userid = Convert.ToInt32(loginTbxUserId.Text);
                password = loginTbxPassword.Text;

                if (Convert.ToString(dt.Rows[0][1]) == "False")
                {
                    this.Hide();
                    userBookSearch ubs = new userBookSearch();
                    ubs.Show();
                }
                else
                {
                    this.Hide();
                    admStartPage asp = new admStartPage();
                    asp.Show();
                }
            }
            else
            {
                MessageBox.Show("The entered USER ID or PASSWORD is WRONG.\nPlease check and try again.\nIf you have forgotten the password then go to the librarian to create a new one.");
                clear();
            }
        }
    }
}