import java.io.*;
import javax.servlet.*;
import javax.servlet.http.*;
import java.sql.*;

public class add extends HttpServlet {

    protected void doPost(HttpServletRequest request, HttpServletResponse response)
            throws ServletException, IOException {
        response.setContentType("text/html;charset=UTF-8");
        PrintWriter out = response.getWriter();

        String iusername = request.getParameter("iusername");
        String ipass = request.getParameter("ipassword");
        int iage = Integer.parseInt(request.getParameter("iage"));


                if(checkExist(iusername))
        {

            out.println( " <center> <font face=\"verdana\" color=\"red\"> Username Taken</font>  </center>");

           RequestDispatcher rs = request.getRequestDispatcher("signup.html");
           rs.include(request, response);

        }
        else
        {
            addUser(iusername,ipass,iage);

           RequestDispatcher rs = request.getRequestDispatcher("login.html");
           rs.include(request, response);
        }





    }


        public static void addUser(String iusername, String ipass, int iage){
        try {

            String password=ipass;
            String username=iusername;
            int age=iage;
            Class.forName("org.apache.derby.jdbc.EmbeddedDriver");
            Connection con = DriverManager.getConnection("jdbc:derby://localhost:1527/test", "root", "root");



           PreparedStatement sp = con.prepareStatement("insert into users(username,password,age) values('"+username+"','"+password+"',?)");
           sp.setInt(1, age);
           sp.executeUpdate();


        } catch (ClassNotFoundException | SQLException e) {
        }

        }


                public static boolean checkExist(String iusername){
                    boolean exists = false;
        try {
            String username=iusername;
            Class.forName("org.apache.derby.jdbc.EmbeddedDriver");
            Connection con = DriverManager.getConnection("jdbc:derby://localhost:1527/test", "root", "root");


            PreparedStatement ps = con.prepareStatement("select * from users where username=?");
            ps.setString(1, username);
            ResultSet rs = ps.executeQuery();
            exists = rs.next();


        } catch (ClassNotFoundException | SQLException e) {
        }
       return exists;
        }



}