/*
 * Copyright 2015-2022 the original author or authors.
 *
 * All rights reserved. This program and the accompanying materials are
 * made available under the terms of the Eclipse Public License v2.0 which
 * accompanies this distribution and is available at
 *
 * https://www.eclipse.org/legal/epl-v20.html
 */

package org.junit.platform.reporting.legacy.xml;

import static org.apiguardian.api.API.Status.STABLE;

import java.io.IOException;
import java.io.PrintWriter;
import java.io.Writer;
import java.nio.file.Files;
import java.nio.file.Path;
import java.nio.file.Paths;
import java.time.Clock;

import javax.xml.stream.XMLStreamException;

import org.apiguardian.api.API;
import org.junit.platform.engine.TestExecutionResult;
import org.junit.platform.engine.UniqueId;
import org.junit.platform.engine.reporting.ReportEntry;
import org.junit.platform.launcher.TestExecutionListener;
import org.junit.platform.launcher.TestIdentifier;
import org.junit.platform.launcher.TestPlan;

/**
 * {@code LegacyXmlReportGeneratingListener} is a {@link TestExecutionListener} that
 * generates a separate XML report for each {@linkplain TestPlan#getRoots() root}
 * in the {@link TestPlan}.
 *
 * <p>Note that the generated XML format is compatible with the <em>legacy</em>
 * de facto standard for JUnit 4 based test reports that was made popular by the
 * Ant build system.
 *
 * @since 1.4
 * @see org.junit.platform.launcher.listeners.LoggingListener
 * @see org.junit.platform.launcher.listeners.SummaryGeneratingListener
 */
@API(status = STABLE, since = "1.7")
public class LegacyXmlReportGeneratingListener implements TestExecutionListener {

	private final Path reportsDir;
	private final PrintWriter out;
	private final Clock clock;

	private XmlReportData reportData;

	public LegacyXmlReportGeneratingListener(Path reportsDir, PrintWriter out) {
		this(reportsDir, out, Clock.systemDefaultZone());
	}

	// For tests only
	LegacyXmlReportGeneratingListener(String reportsDir, PrintWriter out, Clock clock) {
		this(Paths.get(reportsDir), out, clock);
	}

	private LegacyXmlReportGeneratingListener(Path reportsDir, PrintWriter out, Clock clock) {
		this.reportsDir = reportsDir;
		this.out = out;
		this.clock = clock;
	}

	@Override
	public void testPlanExecutionStarted(TestPlan testPlan) {
		this.reportData = new XmlReportData(testPlan, clock);
		try {
			Files.createDirectories(this.reportsDir);
		}
		catch (IOException e) {
			printException("Could not create reports directory: " + this.reportsDir, e);
		}
	}

	@Override
	public void testPlanExecutionFinished(TestPlan testPlan) {
		this.reportData = null;
	}

	@Override
	public void executionSkipped(TestIdentifier testIdentifier, String reason) {
		this.reportData.markSkipped(testIdentifier, reason);
		writeXmlReportInCaseOfRoot(testIdentifier);
	}

	@Override
	public void executionStarted(TestIdentifier testIdentifier) {
		this.reportData.markStarted(testIdentifier);
	}

	@Override
	public void reportingEntryPublished(TestIdentifier testIdentifier, ReportEntry entry) {
		this.reportData.addReportEntry(testIdentifier, entry);
	}

	@Override
	public void executionFinished(TestIdentifier testIdentifier, TestExecutionResult result) {
		this.reportData.markFinished(testIdentifier, result);
		writeXmlReportInCaseOfRoot(testIdentifier);
	}

	private void writeXmlReportInCaseOfRoot(TestIdentifier testIdentifier) {
		if (isRoot(testIdentifier)) {
			String rootName = UniqueId.parse(testIdentifier.getUniqueId()).getSegments().get(0).getValue();
			writeXmlReportSafely(testIdentifier, rootName);
		}
	}

	private void writeXmlReportSafely(TestIdentifier testIdentifier, String rootName) {
		Path xmlFile = this.reportsDir.resolve("TEST-" + rootName + ".xml");
		try (Writer fileWriter = Files.newBufferedWriter(xmlFile)) {
			new XmlReportWriter(this.reportData).writeXmlReport(testIdentifier, fileWriter);
		}
		catch (XMLStreamException | IOException e) {
			printException("Could not write XML report: " + xmlFile, e);
		}
	}

	private boolean isRoot(TestIdentifier testIdentifier) {
		return !testIdentifier.getParentId().isPresent();
	}

	private void printException(String message, Exception exception) {
		out.println(message);
		exception.printStackTrace(out);
	}

}
