package servlet;

import java.io.ByteArrayInputStream;
import java.io.IOException;
import java.io.InputStream;
import java.sql.Connection;
import java.util.HashMap;

import javax.servlet.ServletContext;
import javax.servlet.ServletException;
import javax.servlet.ServletOutputStream;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

import connection.SingleConnection;
import net.sf.jasperreports.engine.JRException;
import net.sf.jasperreports.engine.JasperReport;
import net.sf.jasperreports.engine.JasperRunManager;
import net.sf.jasperreports.engine.util.JRLoader;

@WebServlet("/pages/relatorio")
public class RelatorioServlet extends HttpServlet {
    private static final long serialVersionUID = 1L;

    private Connection connection;

    public RelatorioServlet() {
        super();
        this.connection = SingleConnection.getConnection();
    }

    protected void doGet(HttpServletRequest request, HttpServletResponse response)
            throws ServletException, IOException {
        String modo = request.getParameter("modo");
        //String tipo = request.getParameter("tipo");
        geraRelatorio(request, response, modo);
    }

    protected void doPost(HttpServletRequest request, HttpServletResponse response)
            throws ServletException, IOException {
    }

    private void geraRelatorio(HttpServletRequest request, HttpServletResponse response, String modo) throws ServletException, IOException {
        String jasper = "/WEB-INF/report/Carros.jasper";
        ServletContext contexto = getServletContext();
        HashMap<String, Object> param = new HashMap<String, Object>();

        try (ServletOutputStream sos = response.getOutputStream()) {

            JasperReport relatorio = (JasperReport) JRLoader.loadObjectFromFile(contexto.getRealPath(jasper));
            byte[] bytes = JasperRunManager.runReportToPdf(relatorio, param, connection);

            if (bytes != null) {
                response.setContentType("application/pdf");
                response.setContentLength(bytes.length);
                if (modo.equalsIgnoreCase("download")) {
                    response.setHeader("Content-Disposition", "attachment;filename=relatorio.pdf");
                    downloadFile(bytes, sos);
                } else if (modo.equalsIgnoreCase("visualizar")) {
                    sos.write(bytes);
                    sos.flush();
                }
            }

        } catch (JRException e) {
            e.printStackTrace();
        }

    }

    private static void downloadFile(byte[] bytes, ServletOutputStream sos) {
        try (InputStream i = new ByteArrayInputStream(bytes)) {
            int bytesRead = i.read();

            while (bytesRead != -1) {
                sos.write(bytesRead);
                bytesRead = i.read();
            }
        } catch (Exception e) {
            e.printStackTrace();
        }

    }

}