/*
 * Copyright 2012-present 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 smoketest.integration.consumer;

import java.io.File;
import java.io.IOException;
import java.io.InputStream;
import java.nio.file.Path;
import java.time.Duration;

import org.awaitility.Awaitility;
import org.junit.jupiter.api.AfterEach;
import org.junit.jupiter.api.Test;
import org.junit.jupiter.api.extension.ExtendWith;
import org.junit.jupiter.api.io.TempDir;
import smoketest.integration.SampleIntegrationApplication;
import smoketest.integration.ServiceProperties;
import smoketest.integration.producer.ProducerApplication;

import org.springframework.boot.SpringApplication;
import org.springframework.boot.test.system.CapturedOutput;
import org.springframework.boot.test.system.OutputCaptureExtension;
import org.springframework.context.ConfigurableApplicationContext;
import org.springframework.core.io.DefaultResourceLoader;
import org.springframework.core.io.Resource;
import org.springframework.core.io.support.ResourcePatternUtils;
import org.springframework.util.StreamUtils;

import static org.assertj.core.api.Assertions.assertThat;
import static org.hamcrest.Matchers.containsString;

/**
 * Basic integration tests for service demo application.
 *
 * @author Dave Syer
 * @author Andy Wilkinson
 */
@ExtendWith(OutputCaptureExtension.class)
class SampleIntegrationApplicationTests {

	private ConfigurableApplicationContext context;

	@AfterEach
	void stopAndCheck(CapturedOutput output) {
		assertThat(output).doesNotContain("WARN");
		if (this.context != null) {
			this.context.close();
		}
	}

	@Test
	void testVanillaExchange(@TempDir Path temp) {
		File inputDir = new File(temp.toFile(), "input");
		File outputDir = new File(temp.toFile(), "output");
		this.context = SpringApplication.run(SampleIntegrationApplication.class, "--service.input-dir=" + inputDir,
				"--service.output-dir=" + outputDir);
		SpringApplication.run(ProducerApplication.class, "World", "--service.input-dir=" + inputDir,
				"--service.output-dir=" + outputDir);
		awaitOutputContaining(outputDir, "Hello World");
	}

	@Test
	void testMessageGateway(@TempDir Path temp) {
		File inputDir = new File(temp.toFile(), "input");
		File outputDir = new File(temp.toFile(), "output");
		this.context = SpringApplication.run(SampleIntegrationApplication.class, "testviamg",
				"--service.input-dir=" + inputDir, "--service.output-dir=" + outputDir);
		awaitOutputContaining(this.context.getBean(ServiceProperties.class).getOutputDir(), "testviamg");
	}

	private void awaitOutputContaining(File outputDir, String requiredContents) {
		Awaitility.waitAtMost(Duration.ofSeconds(30))
			.until(() -> outputIn(outputDir), containsString(requiredContents));
	}

	private String outputIn(File outputDir) throws IOException {
		Resource[] resources = findResources(outputDir);
		if (resources.length == 0) {
			return null;
		}
		return readResources(resources);
	}

	private Resource[] findResources(File outputDir) throws IOException {
		return ResourcePatternUtils.getResourcePatternResolver(new DefaultResourceLoader())
			.getResources("file:" + outputDir.getAbsolutePath() + "/*.txt");
	}

	private String readResources(Resource[] resources) throws IOException {
		StringBuilder builder = new StringBuilder();
		for (Resource resource : resources) {
			try (InputStream input = resource.getInputStream()) {
				builder.append(new String(StreamUtils.copyToByteArray(input)));
			}
		}
		return builder.toString();
	}

}
