/*
 *  Copyright 2013-2016 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
 *
 *       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.springframework.cloud.contract.verifier.messaging.stream;

import java.util.Map;
import java.util.concurrent.TimeUnit;

import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.cloud.contract.verifier.messaging.MessageVerifier;
import org.springframework.cloud.stream.config.BindingProperties;
import org.springframework.cloud.stream.config.ChannelBindingServiceProperties;
import org.springframework.cloud.stream.test.binder.MessageCollector;
import org.springframework.context.ApplicationContext;
import org.springframework.messaging.Message;
import org.springframework.messaging.MessageChannel;

/**
 * @author Marcin Grzejszczak
 */
public class StreamStubMessages implements MessageVerifier<Message<?>> {

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

	private final ApplicationContext context;
	private final MessageCollector messageCollector;
	private final ContractVerifierStreamMessageBuilder builder = new ContractVerifierStreamMessageBuilder();

	@Autowired
	public StreamStubMessages(ApplicationContext context) {
		this.context = context;
		this.messageCollector = context.getBean(MessageCollector.class);
	}

	@Override
	public <T> void send(T payload, Map<String, Object> headers, String destination) {
		send(builder.create(payload, headers), destination);
	}

	@Override
	public void send(Message<?> message, String destination) {
		try {
			MessageChannel messageChannel = context
					.getBean(resolvedDestination(destination), MessageChannel.class);
			messageChannel.send(message);
		}
		catch (Exception e) {
			log.error("Exception occurred while trying to send a message [" + message
					+ "] " + "to a channel with name [" + destination + "]", e);
			throw e;
		}
	}

	@Override
	public Message<?> receive(String destination, long timeout, TimeUnit timeUnit) {
		try {
			MessageChannel messageChannel = context
					.getBean(resolvedDestination(destination), MessageChannel.class);
			return messageCollector.forChannel(messageChannel).poll(timeout, timeUnit);
		}
		catch (Exception e) {
			log.error("Exception occurred while trying to read a message from "
					+ " a channel with name [" + destination + "]", e);
			throw new RuntimeException(e);
		}
	}

	private String resolvedDestination(String destination) {
		ChannelBindingServiceProperties channelBindingServiceProperties = context
				.getBean(ChannelBindingServiceProperties.class);
		String resolvedDestination = destination;
		for (Map.Entry<String, BindingProperties> entry : channelBindingServiceProperties
				.getBindings().entrySet()) {
			if (entry.getValue().getDestination().equals(destination)) {
				log.debug("Found a channel named [{}] with destination [{}]",
						entry.getKey(), destination);
				return entry.getKey();
			}
		}
		log.debug(
				"No destination named [{}] was found. Assuming that the destination equals the channel name",
				destination);
		return resolvedDestination;
	}

	@Override
	public Message<?> receive(String destination) {
		return receive(destination, 5, TimeUnit.SECONDS);
	}

}
