/*
 * Copyright 2015-2022 the original author or authors.
 *
 * 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
 *
 *      https://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.springframework.cloud.fn.consumer.sftp;

import java.util.function.Consumer;

import org.apache.sshd.sftp.client.SftpClient;

import org.springframework.boot.context.properties.EnableConfigurationProperties;
import org.springframework.cloud.fn.common.config.ComponentCustomizer;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.context.annotation.Import;
import org.springframework.integration.dsl.IntegrationFlow;
import org.springframework.integration.dsl.IntegrationFlowBuilder;
import org.springframework.integration.dsl.IntegrationFlows;
import org.springframework.integration.file.remote.session.SessionFactory;
import org.springframework.integration.sftp.dsl.Sftp;
import org.springframework.integration.sftp.dsl.SftpMessageHandlerSpec;
import org.springframework.integration.sftp.session.SftpRemoteFileTemplate;
import org.springframework.lang.Nullable;
import org.springframework.messaging.Message;

/**
 * Configuration for SFTP Consumer.
 * @author Soby Chacko
 * @author Corneil du Plessis
 */
@Configuration(proxyBeanMethods = false)
@EnableConfigurationProperties(SftpConsumerProperties.class)
@Import(SftpConsumerSessionFactoryConfiguration.class)
public class SftpConsumerConfiguration {

	@Bean
	public IntegrationFlow ftpOutboundFlow(SftpConsumerProperties properties,
			SessionFactory<SftpClient.DirEntry> ftpSessionFactory,
			@Nullable ComponentCustomizer<SftpMessageHandlerSpec> sftpMessageHandlerSpecCustomizer) {

		IntegrationFlowBuilder integrationFlowBuilder =
				IntegrationFlows.from(MessageConsumer.class, (gateway) -> gateway.beanName("sftpConsumer"));

		SftpMessageHandlerSpec handlerSpec =
				Sftp.outboundAdapter(new SftpRemoteFileTemplate(ftpSessionFactory), properties.getMode())
						.remoteDirectory(properties.getRemoteDir())
						.temporaryRemoteDirectory(properties.getTemporaryRemoteDir())
						.remoteFileSeparator(properties.getRemoteFileSeparator())
						.autoCreateDirectory(properties.isAutoCreateDir())
						.useTemporaryFileName(properties.isUseTemporaryFilename())
						.temporaryFileSuffix(properties.getTmpFileSuffix());
		if (properties.getFilenameExpression() != null) {
			handlerSpec.fileNameExpression(properties.getFilenameExpression());
		}

		if (sftpMessageHandlerSpecCustomizer != null) {
			sftpMessageHandlerSpecCustomizer.customize(handlerSpec);
		}

		return integrationFlowBuilder
				.handle(handlerSpec)
				.get();
	}

	private interface MessageConsumer extends Consumer<Message<?>> {

	}

}
