/*
 * 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.federation.kerberos;

import org.jboss.logging.Logger;
import org.keycloak.Config;
import org.keycloak.federation.kerberos.impl.KerberosServerSubjectAuthenticator;
import org.keycloak.federation.kerberos.impl.KerberosUsernamePasswordAuthenticator;
import org.keycloak.federation.kerberos.impl.SPNEGOAuthenticator;
import org.keycloak.models.KeycloakSession;
import org.keycloak.models.KeycloakSessionFactory;
import org.keycloak.models.UserFederationProvider;
import org.keycloak.models.UserFederationProviderFactory;
import org.keycloak.models.UserFederationProviderModel;
import org.keycloak.models.UserFederationSyncResult;

import java.util.Collections;
import java.util.Date;
import java.util.Set;

/**
 * Factory for standalone Kerberos federation provider. Standalone means that it's not backed by LDAP. For Kerberos backed by LDAP (like MS AD or ApacheDS environment)
 * you should rather use LDAP Federation Provider.
 *
 * @author <a href="mailto:mposolda@redhat.com">Marek Posolda</a>
 */
public class KerberosFederationProviderFactory implements UserFederationProviderFactory {

    private static final Logger logger = Logger.getLogger(KerberosFederationProviderFactory.class);
    public static final String PROVIDER_NAME = "kerberos";
    @Override
    public UserFederationProvider getInstance(KeycloakSession session, UserFederationProviderModel model) {
        return new KerberosFederationProvider(session, model, this);
    }

    @Override
    public Set<String> getConfigurationOptions() {
        return Collections.emptySet();
    }

    @Override
    public String getId() {
        return PROVIDER_NAME;
    }

    @Override
    public UserFederationSyncResult syncAllUsers(KeycloakSessionFactory sessionFactory, String realmId, UserFederationProviderModel model) {
        logger.warn("Sync users not supported for this provider");
        return UserFederationSyncResult.empty();
    }

    @Override
    public UserFederationSyncResult syncChangedUsers(KeycloakSessionFactory sessionFactory, String realmId, UserFederationProviderModel model, Date lastSync) {
        logger.warn("Sync users not supported for this provider");
        return UserFederationSyncResult.empty();
    }

    @Override
    public UserFederationProvider create(KeycloakSession session) {
        throw new IllegalAccessError("Illegal to call this method");
    }

    @Override
    public void init(Config.Scope config) {

    }

    @Override
    public void postInit(KeycloakSessionFactory factory) {

    }

    @Override
    public void close() {

    }

    protected SPNEGOAuthenticator createSPNEGOAuthenticator(String spnegoToken, CommonKerberosConfig kerberosConfig) {
        KerberosServerSubjectAuthenticator kerberosAuth = createKerberosSubjectAuthenticator(kerberosConfig);
        return new SPNEGOAuthenticator(kerberosConfig, kerberosAuth, spnegoToken);
    }

    protected KerberosServerSubjectAuthenticator createKerberosSubjectAuthenticator(CommonKerberosConfig kerberosConfig) {
        return new KerberosServerSubjectAuthenticator(kerberosConfig);
    }

    protected KerberosUsernamePasswordAuthenticator createKerberosUsernamePasswordAuthenticator(CommonKerberosConfig kerberosConfig) {
        return new KerberosUsernamePasswordAuthenticator(kerberosConfig);
    }
}
