package servlets;

import java.io.IOException;
import java.io.PrintWriter;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.sql.*;

public class xmlinfacven extends HttpServlet {

    private String xml;
    private String eror;

    private Boolean respuesta(){
        Boolean estado;
        try{
                Class.forName("com.mysql.jdbc.Driver");
                Connection conexion = DriverManager.getConnection
                        ("jdbc:mysql://127.0.0.1/proyec", "lector", "lectorpass");
                Statement query = conexion.createStatement(
                        ResultSet.TYPE_SCROLL_INSENSITIVE, ResultSet.CONCUR_READ_ONLY);
                ResultSet rs = query.executeQuery("SELECT idRUT, Nombre FROM clientes");
                rs.afterLast();
                Boolean seguir=rs.previous();
                Integer vez =1;
                while(seguir){
                    this.GenXML(rs.getString("idRUT"), rs.getString("Nombre"), vez);
                    seguir=rs.previous();
                    vez ++;
                }
                rs.close(); query.close(); conexion.close();
                estado = true;
            }catch(SQLException ex){
                this.eror=ex.toString();
               estado=false;
            }catch(Exception ex){
                estado=false;
                this.eror=ex.toString();
            }
        return estado;
    }

    private void GenXML(String rut, String app, Integer vez){
        try {
            if(vez==1){
                this.xml = "<cliente>" +
                "<rut>" + rut +"</rut>" +
                "<nombre>" + app +"</nombre>" +
                "</cliente>";
            }else{
                this.xml=this.xml +
                "<cliente>" +
                "<rut>" + rut +"</rut>" +
                "<nombre>" + app +"</nombre>" +
                "</cliente>";
            }

        }catch(Exception e){

        }
    }

    protected void processRequest(HttpServletRequest request, HttpServletResponse response)
    throws ServletException, IOException {
        Boolean estado;
        estado = respuesta();
        if(estado){
            response.setHeader("Content-Type", "text/xml");
            response.setHeader("Cache-Control", "must-revalidate");
            response.setHeader("Cache-Control", "no-cache");
            PrintWriter out = response.getWriter();
            try {
                String respuesta;
                respuesta = "<?xml version=\"1.0\" encoding=\"UTF-8\" standalone=\"yes\"?>" +
                        "<?xml-stylesheet type=\"text/xsl\" href=\"Stilos/pru_clientes.xsl\"?>" +
                        "<clientes>" +
                        this.xml +
                        "</clientes>";
               out.write(respuesta);
            } finally {
                out.close();
            }
        }else{
            response.setHeader("Content-Type", "text/html");
            PrintWriter out = response.getWriter();
            out.write(this.eror);
        }
    }

    @Override
    protected void doGet(HttpServletRequest request, HttpServletResponse response)
    throws ServletException, IOException {
        processRequest(request, response);
    }

    @Override
    protected void doPost(HttpServletRequest request, HttpServletResponse response)
    throws ServletException, IOException {
        processRequest(request, response);
    }

}