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 * Copyright (c) 2018, Oracle and/or its affiliates. All rights reserved.

 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.

 *

 * This code is free software; you can redistribute it and/or modify it

 * under the terms of the GNU General Public License version 2 only, as

 * published by the Free Software Foundation.  Oracle designates this

 * particular file as subject to the "Classpath" exception as provided

 * by Oracle in the LICENSE file that accompanied this code.

 *

 * This code is distributed in the hope that it will be useful, but WITHOUT

 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or

 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License

 * version 2 for more details (a copy is included in the LICENSE file that

 * accompanied this code).

 *

 * You should have received a copy of the GNU General Public License version

 * 2 along with this work; if not, write to the Free Software Foundation,

 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.

 *

 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA

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package jdk.jfr.event.metadata;

import java.io.IOException;

import java.io.StringReader;

import java.util.ArrayList;

import java.util.Collection;

import java.util.HashMap;

import java.util.HashSet;

import java.util.List;

import java.util.Map;

import java.util.Set;

import javax.xml.parsers.DocumentBuilder;

import javax.xml.parsers.DocumentBuilderFactory;

import javax.xml.parsers.ParserConfigurationException;

import jdk.jfr.Configuration;

import jdk.jfr.EventType;

import jdk.jfr.FlightRecorder;

import jdk.jfr.SettingDescriptor;

import jdk.test.lib.jfr.EventNames;

import org.w3c.dom.Attr;

import org.w3c.dom.Document;

import org.w3c.dom.Element;

import org.w3c.dom.Node;

import org.w3c.dom.NodeList;

import org.xml.sax.InputSource;

import org.xml.sax.SAXException;

 * @test

 * @key jfr

 *

 * @library /test/lib

 * @modules java.xml

 *          jdk.jfr

 *

 * @run main/othervm jdk.jfr.event.metadata.TestDefaultConfigurations

 */

public class TestDefaultConfigurations {

    private static final String LINE_SEPARATOR = System.getProperty("line.separator");

    public static void main(String[] args) throws Exception {

        List<String> errors = new ArrayList<>();

        errors.addAll(testConfiguration(Configuration.getConfiguration("default")));

        errors.addAll(testConfiguration(Configuration.getConfiguration("profile")));

        if (!errors.isEmpty()) {

            throwExceptionWithErrors(errors);

        }

    }

    private static List<String> testConfiguration(Configuration config) throws ParserConfigurationException, SAXException, IOException {

        List<String> errors = new ArrayList<>();

        Map<String, EventType> eventTypeLookup = new HashMap<>();

        for (EventType t : FlightRecorder.getFlightRecorder().getEventTypes()) {

            eventTypeLookup.put(t.getName(), t);

        }

        String content = config.getContents();

        Document doc = createDocument(content);

        Element configuration = doc.getDocumentElement();

        errors.addAll(checkConfiguration(configuration));

        for (Element event : getChildElements(configuration, "event")) {

            String name = event.getAttribute("name");

            EventType cd = eventTypeLookup.get(name);

            if (cd != null) {

                errors.addAll(checkSettings(config, cd, event));

            } else {

                errors.add("Preset '" + config.getName() + "' reference unknown event '" + name + "'");

            }

            eventTypeLookup.remove(name);

        }

        for (String name : eventTypeLookup.keySet()) {

            errors.add("Preset '" + config.getName() + "' doesn't configure event '" + name + "'");

        }

        return errors;

    }

    private static void throwExceptionWithErrors(List<String> errors) throws Exception {

        StringBuilder sb = new StringBuilder();

        for (String error : errors) {

            sb.append(error);

            sb.append(LINE_SEPARATOR);

        }

        throw new Exception(sb.toString());

    }

    private static List<String> checkConfiguration(Element configuration) {

        List<String> errors = new ArrayList<>();

        if (configuration.getAttribute("description").length() < 2) {

            errors.add("Configuration should have a valid description!");

        }

        if (configuration.getAttribute("label").length() < 2) {

            errors.add("Configuration should have a label!");

        }

        if (!configuration.getAttribute("provider").equals("Oracle")) {

            errors.add("Configuration should set provider to 'Oracle'!");

        }

        return errors;

    }

    private static List<String> checkSettings(Configuration config, EventType eventType, Element event) {

        List<String> errors = new ArrayList<>();

        Set<String> requiredSettings = createRequiredSettingNameSet(eventType);

        for (Element setting : getChildElements(event, "setting")) {

            String settingName = setting.getAttribute("name");

            if (requiredSettings.contains(settingName)) {

                requiredSettings.remove(settingName);

            } else {

                errors.add("Setting '" + settingName + "' for event '" + eventType.getName() + "' should not be part of confirguaration '" + config.getName()

                        + "' since it won't have an impact on the event.");

            }

        }

        for (String required : requiredSettings) {

            errors.add("Setting '" + required + "' in event '" + eventType.getName() + "' was not configured in the configuration '" + config.getName() + "'");

        }

        return errors;

    }

    private static Set<String> createRequiredSettingNameSet(EventType cd) {

        Set<String> requiredSettings = new HashSet<>();

        for (SettingDescriptor s : cd.getSettingDescriptors()) {

            requiredSettings.add(s.getName());

        }

        return requiredSettings;

    }

    private static Document createDocument(String content) throws ParserConfigurationException, SAXException, IOException {

        DocumentBuilderFactory dbFactory = DocumentBuilderFactory.newInstance();

        DocumentBuilder dBuilder = dbFactory.newDocumentBuilder();

        Document doc = dBuilder.parse(new InputSource(new StringReader(content)));

        doc.getDocumentElement().normalize();

        // Don't want to add these settings to the jfc-files we ship since they

        // are not useful to configure. They are however needed to make the test

        // pass.

        insertSetting(doc, EventNames.ActiveSetting, "stackTrace", "false");

        insertSetting(doc, EventNames.ActiveSetting, "threshold", "0 ns");

        insertSetting(doc, EventNames.ActiveRecording, "stackTrace", "false");

        insertSetting(doc, EventNames.ActiveRecording, "threshold", "0 ns");

        insertSetting(doc, EventNames.JavaExceptionThrow, "threshold", "0 ns");

        insertSetting(doc, EventNames.JavaErrorThrow, "threshold", "0 ns");

        return doc;

    }

    private static void insertSetting(Document doc, String eventName, String settingName, String settingValue) {

        for (Element event : getChildElements(doc.getDocumentElement(), "event")) {

            Attr attribute = event.getAttributeNode("name");

            if (attribute != null) {

                if (eventName.equals(attribute.getValue())) {

                    Element setting = doc.createElement("setting");

                    setting.setAttribute("name", settingName);

                    setting.setTextContent(settingValue);

                    event.appendChild(setting);

                }

            }

        }

    }

    private static Collection<Element> getChildElements(Element parent, String name) {

        NodeList elementsByTagName = parent.getElementsByTagName(name);

        List<Element> elements = new ArrayList<>();

        for (int i = 0; i < elementsByTagName.getLength(); i++) {

            Node node = elementsByTagName.item(i);

            if (node.getNodeType() == Node.ELEMENT_NODE) {

                elements.add((Element) node);

            }

        }

        return elements;

    }

}