/*
 * Copyright 2016 Red Hat Inc. and/or its affiliates and other contributors
 * as indicated by the @author tags. All rights reserved.
 *
 * 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.services.managers;

import org.keycloak.TokenIdGenerator;
import org.keycloak.connections.httpclient.HttpClientProvider;
import org.keycloak.constants.AdapterConstants;
import org.keycloak.models.ClientModel;
import org.keycloak.models.ClientSessionModel;
import org.keycloak.models.KeycloakSession;
import org.keycloak.models.RealmModel;
import org.keycloak.models.UserModel;
import org.keycloak.models.UserSessionModel;
import org.keycloak.protocol.oidc.TokenManager;
import org.keycloak.representations.adapters.action.GlobalRequestResult;
import org.keycloak.representations.adapters.action.LogoutAction;
import org.keycloak.representations.adapters.action.PushNotBeforeAction;
import org.keycloak.representations.adapters.action.TestAvailabilityAction;
import org.keycloak.services.ServicesLogger;
import org.keycloak.services.util.ResolveRelative;
import org.keycloak.common.util.KeycloakUriBuilder;
import org.keycloak.common.util.MultivaluedHashMap;
import org.keycloak.common.util.StringPropertyReplacer;
import org.keycloak.common.util.Time;

import javax.ws.rs.core.UriBuilder;
import java.io.IOException;
import java.net.URI;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.Collections;
import java.util.LinkedList;
import java.util.List;
import java.util.Map;
import java.util.Set;

/**
 * @author <a href="mailto:bill@burkecentral.com">Bill Burke</a>
 * @version $Revision: 1 $
 */
public class ResourceAdminManager {
    protected static ServicesLogger logger = ServicesLogger.ROOT_LOGGER;
    private static final String CLIENT_SESSION_HOST_PROPERTY = "${application.session.host}";

    private KeycloakSession session;

    public ResourceAdminManager(KeycloakSession session) {
        this.session = session;
    }

    public static String resolveUri(URI requestUri, String rootUrl, String uri) {
        String absoluteURI = ResolveRelative.resolveRelativeUri(requestUri, rootUrl, uri);
        return StringPropertyReplacer.replaceProperties(absoluteURI);

   }

    public static String getManagementUrl(URI requestUri, ClientModel client) {
        String mgmtUrl = client.getManagementUrl();
        if (mgmtUrl == null || mgmtUrl.equals("")) {
            return null;
        }

        String absoluteURI = ResolveRelative.resolveRelativeUri(requestUri, client.getRootUrl(), mgmtUrl);

        // this is for resolving URI like "http://${jboss.host.name}:8080/..." in order to send request to same machine and avoid request to LB in cluster environment
        return StringPropertyReplacer.replaceProperties(absoluteURI);
    }

    // For non-cluster setup, return just single configured managementUrls
    // For cluster setup, return the management Urls corresponding to all registered cluster nodes
    private List<String> getAllManagementUrls(URI requestUri, ClientModel client) {
        String baseMgmtUrl = getManagementUrl(requestUri, client);
        if (baseMgmtUrl == null) {
            return Collections.emptyList();
        }

        Set<String> registeredNodesHosts = new ClientManager().validateRegisteredNodes(client);

        // No-cluster setup
        if (registeredNodesHosts.isEmpty()) {
            return Arrays.asList(baseMgmtUrl);
        }

        List<String> result = new LinkedList<String>();
        KeycloakUriBuilder uriBuilder = KeycloakUriBuilder.fromUri(baseMgmtUrl);
        for (String nodeHost : registeredNodesHosts) {
            String currentNodeUri = uriBuilder.clone().host(nodeHost).build().toString();
            result.add(currentNodeUri);
        }

        return result;
    }

    public void logoutUser(URI requestUri, RealmModel realm, UserModel user, KeycloakSession keycloakSession) {
        List<UserSessionModel> userSessions = keycloakSession.sessions().getUserSessions(realm, user);
        logoutUserSessions(requestUri, realm, userSessions);
    }

    protected void logoutUserSessions(URI requestUri, RealmModel realm, List<UserSessionModel> userSessions) {
        // Map from "app" to clientSessions for this app
        MultivaluedHashMap<ClientModel, ClientSessionModel> clientSessions = new MultivaluedHashMap<ClientModel, ClientSessionModel>();
        for (UserSessionModel userSession : userSessions) {
            putClientSessions(clientSessions, userSession);
        }

        logger.debugv("logging out {0} resources ", clientSessions.size());
        //logger.infov("logging out resources: {0}", clientSessions);

        for (Map.Entry<ClientModel, List<ClientSessionModel>> entry : clientSessions.entrySet()) {
            logoutClientSessions(requestUri, realm, entry.getKey(), entry.getValue());
        }
    }

    private void putClientSessions(MultivaluedHashMap<ClientModel, ClientSessionModel> clientSessions, UserSessionModel userSession) {
        for (ClientSessionModel clientSession : userSession.getClientSessions()) {
            ClientModel client = clientSession.getClient();
            clientSessions.add(client, clientSession);
        }
    }

    public void logoutUserFromClient(URI requestUri, RealmModel realm, ClientModel resource, UserModel user) {
        List<UserSessionModel> userSessions = session.sessions().getUserSessions(realm, user);
        List<ClientSessionModel> ourAppClientSessions = null;
        if (userSessions != null) {
            MultivaluedHashMap<ClientModel, ClientSessionModel> clientSessions = new MultivaluedHashMap<ClientModel, ClientSessionModel>();
            for (UserSessionModel userSession : userSessions) {
                putClientSessions(clientSessions, userSession);
            }
            ourAppClientSessions = clientSessions.get(resource);
        }

        logoutClientSessions(requestUri, realm, resource, ourAppClientSessions);
    }

    public boolean logoutClientSession(URI requestUri, RealmModel realm, ClientModel resource, ClientSessionModel clientSession) {
        return logoutClientSessions(requestUri, realm, resource, Arrays.asList(clientSession));
    }

    protected boolean logoutClientSessions(URI requestUri, RealmModel realm, ClientModel resource, List<ClientSessionModel> clientSessions) {
        String managementUrl = getManagementUrl(requestUri, resource);
        if (managementUrl != null) {

            // Key is host, value is list of http sessions for this host
            MultivaluedHashMap<String, String> adapterSessionIds = null;
            List<String> userSessions = new LinkedList<>();
            if (clientSessions != null && clientSessions.size() > 0) {
                adapterSessionIds = new MultivaluedHashMap<String, String>();
                for (ClientSessionModel clientSession : clientSessions) {
                    String adapterSessionId = clientSession.getNote(AdapterConstants.CLIENT_SESSION_STATE);
                    if (adapterSessionId != null) {
                        String host = clientSession.getNote(AdapterConstants.CLIENT_SESSION_HOST);
                        adapterSessionIds.add(host, adapterSessionId);
                    }
                    if (clientSession.getUserSession() != null) userSessions.add(clientSession.getUserSession().getId());
                }
            }

            if (adapterSessionIds == null || adapterSessionIds.isEmpty()) {
                logger.debugv("Can't logout {0}: no logged adapter sessions", resource.getClientId());
                return false;
            }

            if (managementUrl.contains(CLIENT_SESSION_HOST_PROPERTY)) {
                boolean allPassed = true;
                // Send logout separately to each host (needed for single-sign-out in cluster for non-distributable apps - KEYCLOAK-748)
                for (Map.Entry<String, List<String>> entry : adapterSessionIds.entrySet()) {
                    String host = entry.getKey();
                    List<String> sessionIds = entry.getValue();
                    String currentHostMgmtUrl = managementUrl.replace(CLIENT_SESSION_HOST_PROPERTY, host);
                    allPassed = sendLogoutRequest(realm, resource, sessionIds, userSessions, 0, currentHostMgmtUrl) && allPassed;
                }

                return allPassed;
            } else {
                // Send single logout request
                List<String> allSessionIds = new ArrayList<String>();
                for (List<String> currentIds : adapterSessionIds.values()) {
                    allSessionIds.addAll(currentIds);
                }

                return sendLogoutRequest(realm, resource, allSessionIds, userSessions, 0, managementUrl);
            }
        } else {
            logger.debugv("Can't logout {0}: no management url", resource.getClientId());
            return false;
        }
    }

    // Methods for logout all

    public GlobalRequestResult logoutAll(URI requestUri, RealmModel realm) {
        realm.setNotBefore(Time.currentTime());
        List<ClientModel> resources = realm.getClients();
        logger.debugv("logging out {0} resources ", resources.size());

        GlobalRequestResult finalResult = new GlobalRequestResult();
        for (ClientModel resource : resources) {
            GlobalRequestResult currentResult = logoutClient(requestUri, realm, resource, realm.getNotBefore());
            finalResult.addAll(currentResult);
        }
        return finalResult;
    }

    public GlobalRequestResult logoutClient(URI requestUri, RealmModel realm, ClientModel resource) {
        resource.setNotBefore(Time.currentTime());
        return logoutClient(requestUri, realm, resource, resource.getNotBefore());
    }


    protected GlobalRequestResult logoutClient(URI requestUri, RealmModel realm, ClientModel resource, int notBefore) {
        List<String> mgmtUrls = getAllManagementUrls(requestUri, resource);
        if (mgmtUrls.isEmpty()) {
            logger.debug("No management URL or no registered cluster nodes for the client " + resource.getClientId());
            return new GlobalRequestResult();
        }

        if (logger.isDebugEnabled()) logger.debug("Send logoutClient for URLs: " + mgmtUrls);

        // Propagate this to all hosts
        GlobalRequestResult result = new GlobalRequestResult();
        for (String mgmtUrl : mgmtUrls) {
            if (sendLogoutRequest(realm, resource, null, null, notBefore, mgmtUrl)) {
                result.addSuccessRequest(mgmtUrl);
            } else {
                result.addFailedRequest(mgmtUrl);
            }
        }
        return result;
    }

    protected boolean sendLogoutRequest(RealmModel realm, ClientModel resource, List<String> adapterSessionIds, List<String> userSessions, int notBefore, String managementUrl) {
        LogoutAction adminAction = new LogoutAction(TokenIdGenerator.generateId(), Time.currentTime() + 30, resource.getClientId(), adapterSessionIds, notBefore, userSessions);
        String token = new TokenManager().encodeToken(realm, adminAction);
        if (logger.isDebugEnabled()) logger.debugv("logout resource {0} url: {1} sessionIds: " + adapterSessionIds, resource.getClientId(), managementUrl);
        URI target = UriBuilder.fromUri(managementUrl).path(AdapterConstants.K_LOGOUT).build();
        try {
            int status = session.getProvider(HttpClientProvider.class).postText(target.toString(), token);
            boolean success = status == 204 || status == 200;
            logger.debugf("logout success for %s: %s", managementUrl, success);
            return success;
        } catch (IOException e) {
            logger.logoutFailed(e, resource.getClientId());
            return false;
        }
    }

    public GlobalRequestResult pushRealmRevocationPolicy(URI requestUri, RealmModel realm) {
        GlobalRequestResult finalResult = new GlobalRequestResult();
        for (ClientModel client : realm.getClients()) {
            GlobalRequestResult currentResult = pushRevocationPolicy(requestUri, realm, client, realm.getNotBefore());
            finalResult.addAll(currentResult);
        }
        return finalResult;
    }

    public GlobalRequestResult pushClientRevocationPolicy(URI requestUri, RealmModel realm, ClientModel client) {
        return pushRevocationPolicy(requestUri, realm, client, client.getNotBefore());
    }


    protected GlobalRequestResult pushRevocationPolicy(URI requestUri, RealmModel realm, ClientModel resource, int notBefore) {
        List<String> mgmtUrls = getAllManagementUrls(requestUri, resource);
        if (mgmtUrls.isEmpty()) {
            logger.debugf("No management URL or no registered cluster nodes for the client %s", resource.getClientId());
            return new GlobalRequestResult();
        }

        if (logger.isDebugEnabled()) logger.debug("Sending push revocation to URLS: " + mgmtUrls);

        // Propagate this to all hosts
        GlobalRequestResult result = new GlobalRequestResult();
        for (String mgmtUrl : mgmtUrls) {
            if (sendPushRevocationPolicyRequest(realm, resource, notBefore, mgmtUrl)) {
                result.addSuccessRequest(mgmtUrl);
            } else {
                result.addFailedRequest(mgmtUrl);
            }
        }
        return result;
    }

    protected boolean sendPushRevocationPolicyRequest(RealmModel realm, ClientModel resource, int notBefore, String managementUrl) {
        PushNotBeforeAction adminAction = new PushNotBeforeAction(TokenIdGenerator.generateId(), Time.currentTime() + 30, resource.getClientId(), notBefore);
        String token = new TokenManager().encodeToken(realm, adminAction);
        logger.debugv("pushRevocation resource: {0} url: {1}", resource.getClientId(), managementUrl);
        URI target = UriBuilder.fromUri(managementUrl).path(AdapterConstants.K_PUSH_NOT_BEFORE).build();
        try {
            int status = session.getProvider(HttpClientProvider.class).postText(target.toString(), token);
            boolean success = status == 204 || status == 200;
            logger.debugf("pushRevocation success for %s: %s", managementUrl, success);
            return success;
        } catch (IOException e) {
            logger.failedToSendRevocation(e);
            return false;
        }
    }

    public GlobalRequestResult testNodesAvailability(URI requestUri, RealmModel realm, ClientModel client) {
        List<String> mgmtUrls = getAllManagementUrls(requestUri, client);
        if (mgmtUrls.isEmpty()) {
            logger.debug("No management URL or no registered cluster nodes for the application " + client.getClientId());
            return new GlobalRequestResult();
        }


        if (logger.isDebugEnabled()) logger.debug("Sending test nodes availability: " + mgmtUrls);

        // Propagate this to all hosts
        GlobalRequestResult result = new GlobalRequestResult();
        for (String mgmtUrl : mgmtUrls) {
            if (sendTestNodeAvailabilityRequest(realm, client, mgmtUrl)) {
                result.addSuccessRequest(mgmtUrl);
            } else {
                result.addFailedRequest(mgmtUrl);
            }
        }
        return result;
    }

    protected boolean sendTestNodeAvailabilityRequest(RealmModel realm, ClientModel client, String managementUrl) {
        TestAvailabilityAction adminAction = new TestAvailabilityAction(TokenIdGenerator.generateId(), Time.currentTime() + 30, client.getClientId());
        String token = new TokenManager().encodeToken(realm, adminAction);
        logger.debugv("testNodes availability resource: {0} url: {1}", client.getClientId(), managementUrl);
        URI target = UriBuilder.fromUri(managementUrl).path(AdapterConstants.K_TEST_AVAILABLE).build();
        try {
            int status = session.getProvider(HttpClientProvider.class).postText(target.toString(), token);
            boolean success = status == 204 || status == 200;
            logger.debugf("testAvailability success for %s: %s", managementUrl, success);
            return success;
        } catch (IOException e) {
            logger.availabilityTestFailed(managementUrl);
            return false;
        }
   }

}
