/*
 * Copyright 2016 Red Hat, Inc. and/or its affiliates
 * and other contributors as indicated by the @author tags.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 * http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package org.keycloak.adapters.undertow;

import io.undertow.security.api.SecurityContext;
import io.undertow.server.HttpServerExchange;
import io.undertow.servlet.api.ConfidentialPortManager;
import io.undertow.servlet.handlers.ServletRequestContext;
import io.undertow.util.Headers;
import org.jboss.logging.Logger;
import org.keycloak.adapters.AdapterDeploymentContext;
import org.keycloak.adapters.AdapterTokenStore;
import org.keycloak.adapters.KeycloakDeployment;
import org.keycloak.adapters.NodesRegistrationManagement;
import org.keycloak.adapters.RequestAuthenticator;
import org.keycloak.adapters.spi.HttpFacade;
import org.keycloak.enums.TokenStore;

import javax.servlet.RequestDispatcher;
import javax.servlet.ServletException;
import javax.servlet.ServletRequest;
import javax.servlet.ServletResponse;
import java.io.IOException;

/**
 * @author <a href="mailto:bill@burkecentral.com">Bill Burke</a>
 * @author Stan Silvert ssilvert@redhat.com (C) 2014 Red Hat Inc.
 * @version $Revision: 1 $
 */
public class ServletKeycloakAuthMech extends AbstractUndertowKeycloakAuthMech {
    private static final Logger log = Logger.getLogger(ServletKeycloakAuthMech.class);

    protected NodesRegistrationManagement nodesRegistrationManagement;
    protected ConfidentialPortManager portManager;

    public ServletKeycloakAuthMech(AdapterDeploymentContext deploymentContext, UndertowUserSessionManagement userSessionManagement,
                                   NodesRegistrationManagement nodesRegistrationManagement, ConfidentialPortManager portManager,
                                   String errorPage) {
        super(deploymentContext, userSessionManagement, errorPage);
        this.nodesRegistrationManagement = nodesRegistrationManagement;
        this.portManager = portManager;
    }

    @Override
    protected Integer servePage(HttpServerExchange exchange, String location) {
        final ServletRequestContext servletRequestContext = exchange.getAttachment(ServletRequestContext.ATTACHMENT_KEY);
        ServletRequest req = servletRequestContext.getServletRequest();
        ServletResponse resp = servletRequestContext.getServletResponse();
        RequestDispatcher disp = req.getRequestDispatcher(location);
        //make sure the login page is never cached
        exchange.getResponseHeaders().add(Headers.CACHE_CONTROL, "no-cache, no-store, must-revalidate");
        exchange.getResponseHeaders().add(Headers.PRAGMA, "no-cache");
        exchange.getResponseHeaders().add(Headers.EXPIRES, "0");


        try {
            disp.forward(req, resp);
        } catch (ServletException e) {
            throw new RuntimeException(e);
        } catch (IOException e) {
            throw new RuntimeException(e);
        }
        return null;
    }

    @Override
    public AuthenticationMechanismOutcome authenticate(HttpServerExchange exchange, SecurityContext securityContext) {
        UndertowHttpFacade facade = createFacade(exchange);
        KeycloakDeployment deployment = deploymentContext.resolveDeployment(facade);
        if (!deployment.isConfigured()) {
            return AuthenticationMechanismOutcome.NOT_ATTEMPTED;
        }

        nodesRegistrationManagement.tryRegister(deployment);

        RequestAuthenticator authenticator = createRequestAuthenticator(deployment, exchange, securityContext, facade);

        return keycloakAuthenticate(exchange, securityContext, authenticator);
    }

    protected RequestAuthenticator createRequestAuthenticator(KeycloakDeployment deployment, HttpServerExchange exchange, SecurityContext securityContext, UndertowHttpFacade facade) {

        int confidentialPort = getConfidentilPort(exchange);
        AdapterTokenStore tokenStore = getTokenStore(exchange, facade, deployment, securityContext);
        return new ServletRequestAuthenticator(facade, deployment,
                confidentialPort, securityContext, exchange, tokenStore);
    }

    protected int getConfidentilPort(HttpServerExchange exchange) {
        int confidentialPort = 8443;
        if (exchange.getRequestScheme().equalsIgnoreCase("HTTPS")) {
            confidentialPort = exchange.getHostPort();
        } else if (portManager != null) {
            confidentialPort = portManager.getConfidentialPort(exchange);
        }
        return confidentialPort;
    }

    @Override
    protected AdapterTokenStore getTokenStore(HttpServerExchange exchange, HttpFacade facade, KeycloakDeployment deployment, SecurityContext securityContext) {
        if (deployment.getTokenStore() == TokenStore.SESSION) {
            return new ServletSessionTokenStore(exchange, deployment, sessionManagement, securityContext);
        } else {
            return new UndertowCookieTokenStore(facade, deployment, securityContext);
        }
    }

    @Override
    public UndertowHttpFacade createFacade(HttpServerExchange exchange) {
        return new OIDCServletUndertowHttpFacade(exchange);
    }
}