/**
 * Copyright (c) 2018-2028, lengleng (wangiegie@gmail.com).
 * <p>
 * Licensed under the GNU LESSER GENERAL PUBLIC LICENSE 3.0;
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 * <p>
 * http://www.gnu.org/licenses/lgpl.html
 * <p>
 * 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.springblade.core.swagger;

import org.springframework.beans.BeansException;
import org.springframework.beans.factory.config.BeanPostProcessor;
import org.springframework.boot.autoconfigure.AutoConfiguration;
import org.springframework.context.annotation.Bean;
import org.springframework.util.ReflectionUtils;
import org.springframework.web.servlet.mvc.method.RequestMappingInfoHandlerMapping;
import springfox.documentation.spring.web.plugins.WebMvcRequestHandlerProvider;

import java.lang.reflect.Field;
import java.util.List;
import java.util.stream.Collectors;

/**
 * 解决swagger2与最新版springboot冲突的问题
 *
 * @author Chill
 */
@AutoConfiguration
public class SwaggerHandlerConfiguration {

	@Bean
	public static BeanPostProcessor springfoxHandlerProviderBeanPostProcessor() {
		return new BeanPostProcessor() {

			@Override
			public Object postProcessAfterInitialization(Object bean, String beanName) throws BeansException {
				if (bean instanceof WebMvcRequestHandlerProvider) {
					customizeSpringfoxHandlerMappings(getHandlerMappings(bean));
				}
				return bean;
			}

			private <T extends RequestMappingInfoHandlerMapping> void customizeSpringfoxHandlerMappings(List<T> mappings) {
				List<T> copy = mappings.stream()
					.filter(mapping -> mapping.getPatternParser() == null)
					.collect(Collectors.toList());
				mappings.clear();
				mappings.addAll(copy);
			}
		};
	}

	private static List<RequestMappingInfoHandlerMapping> getHandlerMappings(Object bean) {
		try {
			Field field = ReflectionUtils.findField(bean.getClass(), "handlerMappings");
			field.setAccessible(true);
			return (List<RequestMappingInfoHandlerMapping>) field.get(bean);
		} catch (IllegalArgumentException | IllegalAccessException e) {
			throw new IllegalStateException(e);
		}
	}

}