package at.gv.egovernment.moa.id.protocols.stork2;

import java.io.StringWriter;
import java.util.ArrayList;
import java.util.HashMap;
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.stork.VelocityProvider;
import at.gv.egovernment.moa.id.commons.db.ex.MOADatabaseException;
import at.gv.egovernment.moa.id.config.auth.AuthConfigurationProvider;
import at.gv.egovernment.moa.id.config.auth.OAAuthParameter;
import at.gv.egovernment.moa.id.moduls.IAction;
import at.gv.egovernment.moa.id.moduls.IRequest;
import at.gv.egovernment.moa.id.storage.AssertionStorage;
import at.gv.egovernment.moa.logging.Logger;
import eu.stork.peps.auth.commons.PEPSUtil;
import eu.stork.peps.auth.commons.PersonalAttribute;
import eu.stork.peps.auth.commons.STORKAuthnResponse;
import eu.stork.peps.auth.engine.STORKSAMLEngine;
import eu.stork.peps.exceptions.STORKSAMLEngineException;
import org.apache.velocity.Template;
import org.apache.velocity.VelocityContext;
import org.apache.velocity.app.VelocityEngine;
import org.joda.time.DateTime;
import org.opensaml.common.impl.SecureRandomIdentifierGenerator;

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

/**
 * The ConsentEvaluator assists with fetching user consent on the list of attributes to be sent to the asking S-PEPS.
 */
public class ConsentEvaluator implements IAction {

    /**
     * The Constant ARTIFACT_ID.
     */
    private static final String ARTIFACT_ID = "artifactId";

    /* (non-Javadoc)
     * @see at.gv.egovernment.moa.id.moduls.IAction#processRequest(at.gv.egovernment.moa.id.moduls.IRequest, javax.servlet.http.HttpServletRequest, javax.servlet.http.HttpServletResponse, at.gv.egovernment.moa.id.auth.data.AuthenticationSession)
     */
    public String processRequest(IRequest req, HttpServletRequest httpReq, HttpServletResponse httpResp, AuthenticationSession moasession) throws MOAIDException {

		// - fetch the container
		String artifactId = (String) httpReq.getParameter(ARTIFACT_ID);
		DataContainer container;
		try {
			container = AssertionStorage.getInstance().get(artifactId, DataContainer.class);
		} catch (MOADatabaseException e) {
			Logger.error("Error fetching incomplete Stork response from temporary storage. Most likely a timeout occured.", e);
			throw new MOAIDException("stork.17", null);
		}

		// evaluate response
		for(PersonalAttribute current : container.getResponse().getPersonalAttributeList()) {
			if(null == httpReq.getParameter(current.getName())) {
				current.setStatus("notAvailable");
				current.setValue(new ArrayList<String>());
				current.setComplexValue(new HashMap<String, String>());
			}
		}

        // build and send response
        generateSTORKResponse(httpResp, container);
        
        return "12345"; // AssertionId
    }

	/**
	 * Fills the given HttpResponse with the required web page.
	 *
	 * @param container the container
	 * @param response the response
	 * @param oaParam the oa param
	 * @return the string
	 * @throws MOAIDException the mOAID exception
	 */
	public String requestConsent(DataContainer container, HttpServletResponse response, OAAuthParameter oaParam) throws MOAIDException {
		// prepare redirect
		String newArtifactId;
		try {

			// memorize the container again
			Logger.debug("prepare putting the container into temporary storage...");

			// - generate new key
			newArtifactId = new SecureRandomIdentifierGenerator().generateIdentifier();

			// - put container in temporary store.
			AssertionStorage.getInstance().put(newArtifactId, container);

			Logger.debug("...successful");

		} catch (Exception e1) {
			// TODO should we return the response as is to the PEPS?
			e1.printStackTrace();
            Logger.error("Error putting incomplete Stork response into temporary storage", e1);
			throw new MOAIDException("stork.17", null);
		}

		// ask for consent
		try {
			VelocityEngine velocityEngine = VelocityProvider.getClassPathVelocityEngine();
			Template template = velocityEngine.getTemplate("/resources/templates/stork2_consent.html");
			VelocityContext context = new VelocityContext();

			context.put("action", AuthConfigurationProvider.getInstance().getPublicURLPrefix() + "/stork2/CompleteAuthentication?" + ARTIFACT_ID + "=" + newArtifactId);

			// assemble table
			String table = "";
			for (PersonalAttribute current : container.getResponse().getPersonalAttributeList())
				if ("Available".equals(current.getStatus()))
					table += "<tr><td><input type=\"checkbox\" checked=\"yes\" name=\"" + current.getName() + "\"></td><td>" + current.getName() + "</td></tr>\n";

			context.put("tablecontent", table);

			StringWriter writer = new StringWriter();
			template.merge(context, writer);
			response.getOutputStream().write(writer.getBuffer().toString().getBytes());

		} catch (Exception e) {
			Logger.error("Velocity error: " + e.getMessage());
			throw new MOAIDException("stork.17", null);
		}

		return "12345"; // AssertionId
	}

    /**
     * generates binary response from given response class and fill the given HttpResponse with a SAML Post Binding template.
     *
     * @param httpResp the http resp
     * @param container the container
     * @throws MOAIDException the mOAID exception
     */
    public void generateSTORKResponse(HttpServletResponse httpResp, DataContainer container) throws MOAIDException {
    	MOASTORKRequest request = container.getRequest();
        MOASTORKResponse response = container.getResponse();
        
        Logger.info("generating stork response...");

        try {
            //Get SAMLEngine instance
            STORKSAMLEngine engine = STORKSAMLEngine.getInstance("VIDP");
            Logger.debug("Starting generation of SAML response");
			if(response.isAuthnResponse())
				response.setSTORKAuthnResponse(engine.generateSTORKAuthnResponse(request.getStorkAuthnRequest(), response.getStorkAuthnResponse(), container.getRemoteAddress(), false));
			else
				response.setSTORKAttrResponse(engine.generateSTORKAttrQueryResponse(request.getStorkAttrQueryRequest(), response.getStorkAttrQueryResponse(), container.getRemoteAddress(), "", false));


            //generateSAML Token
            Logger.info("SAML response succesfully generated!");
        } catch (STORKSAMLEngineException e) {
            Logger.error("Failed to generate STORK SAML Response", e);
            throw new MOAIDException("stork.05", null);
        }

        // preparing redirection for the client
        try {
            VelocityEngine velocityEngine = VelocityProvider.getClassPathVelocityEngine();
            Template template = velocityEngine.getTemplate("/resources/templates/stork2_postbinding_template.html");
            VelocityContext context = new VelocityContext();
            
            byte[] blob;
			if(request.isAttrRequest())
            	blob = response.getStorkAttrQueryResponse().getTokenSaml();
            else
            	blob = response.getStorkAuthnResponse().getTokenSaml();

            context.put("SAMLResponse", PEPSUtil.encodeSAMLToken(blob));
            Logger.debug("SAMLResponse original: " + new String(blob));

            Logger.debug("Putting assertion consumer url as action: " + request.getAssertionConsumerServiceURL());
            context.put("action", request.getAssertionConsumerServiceURL());
            Logger.debug("Starting template merge");
            StringWriter writer = new StringWriter();

            Logger.debug("Doing template merge");
            template.merge(context, writer);
            Logger.debug("Template merge done");

            Logger.debug("Sending html content: " + writer.getBuffer().toString());
            Logger.debug("Sending html content2  : " + new String(writer.getBuffer()));

            httpResp.getOutputStream().write(writer.getBuffer().toString().getBytes());

        } catch (Exception e) {
            Logger.error("Velocity error: " + e.getMessage());
        }
    }

    /* (non-Javadoc)
     * @see at.gv.egovernment.moa.id.moduls.IAction#needAuthentication(at.gv.egovernment.moa.id.moduls.IRequest, javax.servlet.http.HttpServletRequest, javax.servlet.http.HttpServletResponse)
     */
    public boolean needAuthentication(IRequest req, HttpServletRequest httpReq, HttpServletResponse httpResp) {
    	// this action does not need any authentication. The authentication is already done by the preceding AuthenticationRequest-Action.
        return false;
    }

    /* (non-Javadoc)
     * @see at.gv.egovernment.moa.id.moduls.IAction#getDefaultActionName()
     */
    public String getDefaultActionName() {
        return STORKProtocol.CONSENT_EVALUATOR;
    }
}