package at.gv.egovernment.moa.id.auth.modules.internal.tasks;

import static at.gv.egovernment.moa.id.auth.MOAIDAuthConstants.*;

import java.io.PrintWriter;

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

import org.apache.commons.lang.StringEscapeUtils;
import org.apache.commons.lang3.ObjectUtils;

import at.gv.egovernment.moa.id.auth.builder.StartAuthenticationBuilder;
import at.gv.egovernment.moa.id.auth.data.AuthenticationSession;
import at.gv.egovernment.moa.id.auth.exception.MOAIDException;
import at.gv.egovernment.moa.id.auth.exception.WrongParametersException;
import at.gv.egovernment.moa.id.auth.servlet.GenerateIFrameTemplateServlet;
import at.gv.egovernment.moa.id.commons.db.ConfigurationDBUtils;
import at.gv.egovernment.moa.id.commons.db.ex.MOADatabaseException;
import at.gv.egovernment.moa.id.process.api.ExecutionContext;
import at.gv.egovernment.moa.id.storage.AuthenticationSessionStoreage;
import at.gv.egovernment.moa.logging.Logger;
import at.gv.egovernment.moa.util.MiscUtil;
import at.gv.egovernment.moa.util.StringUtils;

/**
 * Creates a http form including an embedded {@code InfoBoxReadRequest} for reading the identity link.<p/>
 * In detail:
 * <ul>
 * <li>Renames the moa session id.</li>
 * <li>Removes ExecutionContext property {@linkplain at.gv.egovernment.moa.id.auth.MOAIDAuthConstants#PARAM_SESSIONID PARAM_SESSIONID}.</li>
 * <li>Creates the http form mentioned above.</li>
 * <li>Returns the http form via HttpServletResponse.</li>
 * </ul>
 * Expects:
 * <ul>
 * <li>HttpServletRequest parameter {@linkplain at.gv.egovernment.moa.id.auth.MOAIDAuthConstants#PARAM_SESSIONID PARAM_SESSIONID} <strong>or</strong></li>
 * <li>ExecutionContext property {@linkplain at.gv.egovernment.moa.id.auth.MOAIDAuthConstants#PARAM_SESSIONID PARAM_SESSIONID} (in case of legacy authentication without CCE selection, where the moa session is not provided by request parameter).</li>
 * </ul>
 * Result:
 * <ul>
 * <li>The identity link form via HttpServletResponse.</li>
 * </ul>
 * Possible branches:
 * <ul>
 * <li>In case of STORK authentication
 * <ul>
 * <li>Creates STORK auth SAML request.</li>
 * <li>Creates and returns a form for submitting the SAML request to the CPEPS (post binding).</li>
 * <li>Returns the form via HttpServletResponse.</li>
 * </ul>
 * </li>
 * </ul>
 * Code taken from {@link at.gv.egovernment.moa.id.auth.servlet.GenerateIFrameTemplateServlet}.
 * @see #execute(ExecutionContext, HttpServletRequest, HttpServletResponse)
 *
 */
public class CreateIdentityLinkFormTask extends AbstractAuthServletTask {

	@Override
	public void execute(ExecutionContext executionContext, HttpServletRequest req, HttpServletResponse resp)
			throws Exception {

		String pendingRequestID = null;
		String moasessionid = StringEscapeUtils.escapeHtml(ObjectUtils.defaultIfNull(req.getParameter(PARAM_SESSIONID), (String) executionContext.get(PARAM_SESSIONID)));
		AuthenticationSession moasession = null;
		try {
			
			if (MiscUtil.isEmpty(moasessionid)) {
				Logger.warn("MOASessionID is empty.");
				throw new MOAIDException("auth.18", new Object[] {});
			}
			
			try {
			
				pendingRequestID = AuthenticationSessionStoreage.getPendingRequestID(moasessionid);
				moasession = AuthenticationSessionStoreage.getSession(moasessionid);
				AuthenticationSessionStoreage.changeSessionID(moasession);
				executionContext.remove(PARAM_SESSIONID);
			
			} catch (MOADatabaseException e) {
				Logger.info("MOASession with SessionID=" + moasessionid + " is not found in Database");
				throw new MOAIDException("init.04", new Object[] { moasessionid });

			} catch (Throwable e) {
				Logger.info("No HTTP Session found!");
				throw new MOAIDException("auth.18", new Object[] {});
			}

			StartAuthenticationBuilder startauth = StartAuthenticationBuilder.getInstance();
			String getIdentityLinkForm = startauth.build(moasession, req, resp);

			if (!StringUtils.isEmpty(getIdentityLinkForm)) {
				resp.setContentType("text/html;charset=UTF-8");
				PrintWriter out = new PrintWriter(resp.getOutputStream());
				out.print(getIdentityLinkForm);
				out.flush();
				Logger.debug("Finished GET " + GenerateIFrameTemplateServlet.class);
			}
			
		} catch (WrongParametersException ex) {
			handleWrongParameters(ex, req, resp);
		}

		catch (MOAIDException ex) {
			handleError(null, ex, req, resp, pendingRequestID);

		} catch (Exception e) {
			Logger.error("CreateIdentityLinkFormTask has an interal Error.", e);

		}

		finally {
			ConfigurationDBUtils.closeSession();
		}
	}

}