package at.gv.egiz.pdfas.web.servlets;

import java.io.IOException;
import java.io.OutputStream;
import java.security.cert.CertificateEncodingException;
import java.util.List;

import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import at.gv.egiz.pdfas.common.exceptions.PdfAsException;
import at.gv.egiz.pdfas.lib.api.verify.VerifyResult;
import at.gv.egiz.pdfas.web.helper.PdfAsHelper;

public class PDFSignatureCertificateData  extends HttpServlet {

	private static final long serialVersionUID = 1L;

	private static final Logger logger = LoggerFactory
			.getLogger(PDFSignatureCertificateData.class);

	public static final String SIGN_ID = "SIGID";

	/**
	 * @see HttpServlet#HttpServlet()
	 */
	public PDFSignatureCertificateData() {
		super();
	}

	/**
	 * @see HttpServlet#doGet(HttpServletRequest request, HttpServletResponse
	 *      response)
	 */
	protected void doGet(HttpServletRequest request,
			HttpServletResponse response) throws ServletException, IOException {
		this.process(request, response);
	}

	/**
	 * @see HttpServlet#doPost(HttpServletRequest request, HttpServletResponse
	 *      response)
	 */
	protected void doPost(HttpServletRequest request,
			HttpServletResponse response) throws ServletException, IOException {
		this.process(request, response);
	}

	protected void process(HttpServletRequest request,
			HttpServletResponse response) throws ServletException, IOException {
		try {
			if(request.getParameter(SIGN_ID) == null) {
				throw new PdfAsException("Missing Parameter");
			}
			
			String sigID = request.getParameter(SIGN_ID);

			int id = Integer.parseInt(sigID);

			List<VerifyResult> vResult = PdfAsHelper
					.getVerificationResult(request);

			if (id < vResult.size()) {
				VerifyResult res =  vResult.get(id);
				
				response.setHeader(
						"Content-Disposition",
						"inline;filename=cert_" + id + ".cer");
				response.setContentType("application/pkix-cert");
				OutputStream os = response.getOutputStream();
				os.write(res.getSignerCertificate().getEncoded());
				os.close();
			} else {
				logger.error("Verification CERT not found! for id " + request.getParameter(SIGN_ID) + " in session " + request.getSession().getId());
				response.sendError(HttpServletResponse.SC_NOT_FOUND);
			}
		} catch (NumberFormatException e) {
			logger.error("Verification CERT not found! for id " + request.getParameter(SIGN_ID) + " in session " + request.getSession().getId());
			response.sendError(HttpServletResponse.SC_NOT_FOUND);
		} catch (PdfAsException e) {
			logger.error("Verification CERT not found:", e);
			response.sendError(HttpServletResponse.SC_NOT_FOUND);
		} catch (CertificateEncodingException e) {
			logger.error("Verification CERT invalid:", e);
			response.sendError(HttpServletResponse.SC_NOT_FOUND);
		} 
	}

}