<%#
 Copyright 2013-2018 the original author or authors from the JHipster project.

 This file is part of the JHipster project, see http://www.jhipster.tech/
 for more information.

 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 <%=packageName%>.config;

import <%=packageName%>.security.OAuth2AuthenticationSuccessHandler;

import org.apache.commons.lang3.StringUtils;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.beans.BeansException;
import org.springframework.beans.factory.config.BeanPostProcessor;
import org.springframework.boot.web.servlet.FilterRegistrationBean;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.context.annotation.Profile;
import org.springframework.core.Ordered;
import org.springframework.core.PriorityOrdered;
import org.springframework.security.oauth2.client.filter.OAuth2ClientAuthenticationProcessingFilter;
import org.springframework.security.web.FilterChainProxy;
import org.springframework.security.web.SecurityFilterChain;
import org.springframework.web.filter.OncePerRequestFilter;

import javax.servlet.Filter;
import javax.servlet.FilterChain;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;

/**
 * Development only configuration that is Browsersync-aware and redirects to the origin you clicked "login" from.
 * If you split your application into client and server on separate domains, you might want to enable this for prod
 * mode too.
 */
@Configuration
@Profile("dev")
public class OAuth2Configuration {
    public static final String SAVED_LOGIN_ORIGIN_URI = OAuth2Configuration.class.getName() + "_SAVED_ORIGIN";

    private final Logger log = LoggerFactory.getLogger(OAuth2Configuration.class);

    @Bean
    public FilterRegistrationBean saveLoginOriginFilter() {
        Filter filter = new OncePerRequestFilter() {
            @Override
            protected void doFilterInternal(HttpServletRequest request, HttpServletResponse response,
                                            FilterChain filterChain)
                throws ServletException, IOException {
                if (request.getRemoteUser() == null && request.getRequestURI().endsWith("/login")) {
                    String referrer = request.getHeader("referer");
                    if (!StringUtils.isBlank(referrer) &&
                        request.getSession().getAttribute(SAVED_LOGIN_ORIGIN_URI) == null) {
                        log.debug("Saving login origin URI: {}", referrer);
                        request.getSession().setAttribute(SAVED_LOGIN_ORIGIN_URI, referrer);
                    }
                }
                filterChain.doFilter(request, response);
            }
        };
        FilterRegistrationBean bean = new FilterRegistrationBean(filter);
        bean.setOrder(Ordered.HIGHEST_PRECEDENCE);
        return bean;
    }

    @Bean
    public static DefaultRolesPrefixPostProcessor defaultRolesPrefixPostProcessor() {
        return new DefaultRolesPrefixPostProcessor();
    }

    public static class DefaultRolesPrefixPostProcessor implements BeanPostProcessor, PriorityOrdered {

        @Override
        public Object postProcessAfterInitialization(Object bean, String beanName) throws BeansException {
            if (bean instanceof FilterChainProxy) {

                FilterChainProxy chains = (FilterChainProxy) bean;

                for (SecurityFilterChain chain : chains.getFilterChains()) {
                    for (Filter filter : chain.getFilters()) {
                        if (filter instanceof OAuth2ClientAuthenticationProcessingFilter) {
                            OAuth2ClientAuthenticationProcessingFilter oAuth2ClientAuthenticationProcessingFilter =
                                (OAuth2ClientAuthenticationProcessingFilter) filter;
                            oAuth2ClientAuthenticationProcessingFilter
                                .setAuthenticationSuccessHandler(new OAuth2AuthenticationSuccessHandler());
                        }
                    }
                }
            }
            return bean;
        }

        @Override
        public Object postProcessBeforeInitialization(Object bean, String beanName) throws BeansException {
            return bean;
        }

        @Override
        public int getOrder() {
            return PriorityOrdered.HIGHEST_PRECEDENCE;
        }
    }
}