/*

 * Copyright (c) 2015, 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.

 *

 * 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

 * or visit www.oracle.com if you need additional information or have any

 * questions.

 */

package optionsvalidation;

import java.io.BufferedReader;

import java.io.IOException;

import java.io.InputStreamReader;

import java.io.Reader;

import java.util.ArrayList;

import java.util.Arrays;

import java.util.List;

import java.util.LinkedHashMap;

import java.util.Map;

import java.util.StringTokenizer;

import java.util.function.Predicate;

import jdk.test.lib.OutputAnalyzer;

import jdk.test.lib.Platform;

import jdk.test.lib.ProcessTools;

public class JVMOptionsUtils {

    /* Java option which print options with ranges */

    private static final String PRINT_FLAGS_RANGES = "-XX:+PrintFlagsRanges";

    /* StringBuilder to accumulate failed message */

    private static final StringBuilder finalFailedMessage = new StringBuilder();

    /* Used to start the JVM with the same type as current */

    static String VMType;

    static {

        if (Platform.isServer()) {

            VMType = "-server";

        } else if (Platform.isClient()) {

            VMType = "-client";

        } else if (Platform.isMinimal()) {

            VMType = "-minimal";

        } else if (Platform.isGraal()) {

            VMType = "-graal";

        } else {

            VMType = null;

        }

    }

    /**

     * Add dependency for option depending on it's name. E.g. enable G1 GC for

     * G1 options or add prepend options to not hit constraints.

     *

     * @param option option

     */

    private static void addNameDependency(JVMOption option) {

        String name = option.getName();

        if (name.startsWith("G1")) {

            option.addPrepend("-XX:+UseG1GC");

        }

        if (name.startsWith("CMS")) {

            option.addPrepend("-XX:+UseConcMarkSweepGC");

        }

        switch (name) {

            case "MinHeapFreeRatio":

                option.addPrepend("-XX:MaxHeapFreeRatio=100");

                break;

            case "MaxHeapFreeRatio":

                option.addPrepend("-XX:MinHeapFreeRatio=0");

                break;

            case "MinMetaspaceFreeRatio":

                option.addPrepend("-XX:MaxMetaspaceFreeRatio=100");

                break;

            case "MaxMetaspaceFreeRatio":

                option.addPrepend("-XX:MinMetaspaceFreeRatio=0");

                break;

            case "CMSOldPLABMin":

                option.addPrepend("-XX:CMSOldPLABMax=" + option.getMax());

                break;

            case "CMSOldPLABMax":

                option.addPrepend("-XX:CMSOldPLABMin=" + option.getMin());

                break;

            case "CMSPrecleanNumerator":

                option.addPrepend("-XX:CMSPrecleanDenominator=" + option.getMax());

                break;

            case "CMSPrecleanDenominator":

                option.addPrepend("-XX:CMSPrecleanNumerator=" + ((new Integer(option.getMin())) - 1));

                break;

            case "InitialTenuringThreshold":

                option.addPrepend("-XX:MaxTenuringThreshold=" + option.getMax());

                break;

            default:

                /* Do nothing */

                break;

        }

    }

    /**

     * Parse JVM Options. Get input from "inputReader". Parse using

     * "-XX:+PrintFlagsRanges" output format.

     *

     * @param inputReader input data for parsing

     * @param withRanges true if needed options with defined ranges inside JVM

     * @param acceptOrigin predicate for option origins. Origins can be

     * "product", "diagnostic" etc. Accept option only if acceptOrigin evaluates

     * to true.

     * @return map from option name to the JVMOption object

     * @throws IOException if an error occurred while reading the data

     */

    private static Map<String, JVMOption> getJVMOptions(Reader inputReader,

            boolean withRanges, Predicate<String> acceptOrigin) throws IOException {

        BufferedReader reader = new BufferedReader(inputReader);

        String type;

        String line;

        String token;

        String name;

        StringTokenizer st;

        JVMOption option;

        Map<String, JVMOption> allOptions = new LinkedHashMap<>();

        // Skip first line

        line = reader.readLine();

        while ((line = reader.readLine()) != null) {

            /*

             * Parse option from following line:

             * <type> <name> [ <min, optional> ... <max, optional> ] {<origin>}

             */

            st = new StringTokenizer(line);

            type = st.nextToken();

            name = st.nextToken();

            option = JVMOption.createVMOption(type, name);

            /* Skip '[' */

            token = st.nextToken();

            /* Read min range or "..." if range is absent */

            token = st.nextToken();

            if (token.equals("...") == false) {

                if (!withRanges) {

                    /*

                     * Option have range, but asked for options without

                     * ranges => skip it

                     */

                    continue;

                }

                /* Mark this option as option which range is defined in VM */

                option.optionWithRange();

                option.setMin(token);

                /* Read "..." and skip it */

                token = st.nextToken();

                /* Get max value */

                token = st.nextToken();

                option.setMax(token);

            } else if (withRanges) {

                /*

                 * Option not have range, but asked for options with

                 * ranges => skip it

                 */

                continue;

            }

            /* Skip ']' */

            token = st.nextToken();

            /* Read origin of the option */

            token = st.nextToken();

            while (st.hasMoreTokens()) {

                token += st.nextToken();

            };

            token = token.substring(1, token.indexOf("}"));

            if (acceptOrigin.test(token)) {

                addNameDependency(option);

                allOptions.put(name, option);

            }

        }

        return allOptions;

    }

    static void failedMessage(String optionName, String value, boolean valid, String message) {

        String temp;

        if (valid) {

            temp = "valid";

        } else {

            temp = "invalid";

        }

        failedMessage(String.format("Error processing option %s with %s value '%s'! %s",

                optionName, temp, value, message));

    }

    static void failedMessage(String message) {

        System.err.println("TEST FAILED: " + message);

        finalFailedMessage.append(String.format("(%s)%n", message));

    }

    static void printOutputContent(OutputAnalyzer output) {

        System.err.println(String.format("stdout content[%s]", output.getStdout()));

        System.err.println(String.format("stderr content[%s]%n", output.getStderr()));

    }

    /**

     * Return string with accumulated failure messages

     *

     * @return string with accumulated failure messages

     */

    public static String getMessageWithFailures() {

        return finalFailedMessage.toString();

    }

    /**

     * Run command line tests for options passed in the list

     *

     * @param options list of options to test

     * @return number of failed tests

     * @throws Exception if java process can not be started

     */

    public static int runCommandLineTests(List<? extends JVMOption> options) throws Exception {

        int failed = 0;

        for (JVMOption option : options) {

            failed += option.testCommandLine();

        }

        return failed;

    }

    /**

     * Test passed options using DynamicVMOption isValidValue and isInvalidValue

     * methods. Only tests writeable options.

     *

     * @param options list of options to test

     * @return number of failed tests

     */

    public static int runDynamicTests(List<? extends JVMOption> options) {

        int failed = 0;

        for (JVMOption option : options) {

            failed += option.testDynamic();

        }

        return failed;

    }

    /**

     * Test passed options using Jcmd. Only tests writeable options.

     *

     * @param options list of options to test

     * @return number of failed tests

     */

    public static int runJcmdTests(List<? extends JVMOption> options) {

        int failed = 0;

        for (JVMOption option : options) {

            failed += option.testJcmd();

        }

        return failed;

    }

    /**

     * Test passed option using attach method. Only tests writeable options.

     *

     * @param options list of options to test

     * @return number of failed tests

     * @throws Exception if an error occurred while attaching to the target JVM

     */

    public static int runAttachTests(List<? extends JVMOption> options) throws Exception {

        int failed = 0;

        for (JVMOption option : options) {

            failed += option.testAttach();

        }

        return failed;

    }

    /**

     * Get JVM options as map. Can return options with defined ranges or options

     * without range depending on "withRanges" argument. "acceptOrigin"

     * predicate can be used to filter option origin.

     *

     * @param withRanges true if needed options with defined ranges inside JVM

     * @param acceptOrigin predicate for option origins. Origins can be

     * "product", "diagnostic" etc. Accept option only if acceptOrigin evaluates

     * to true.

     * @param additionalArgs additional arguments to the Java process which ran

     * with "-XX:+PrintFlagsRanges"

     * @return map from option name to the JVMOption object

     * @throws Exception if a new process can not be created or an error

     * occurred while reading the data

     */

    public static Map<String, JVMOption> getOptionsAsMap(boolean withRanges, Predicate<String> acceptOrigin,

            String... additionalArgs) throws Exception {

        Map<String, JVMOption> result;

        Process p;

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

        if (additionalArgs.length > 0) {

            runJava.addAll(Arrays.asList(additionalArgs));

        }

        if (VMType != null) {

            runJava.add(VMType);

        }

        runJava.add(PRINT_FLAGS_RANGES);

        runJava.add("-version");

        p = ProcessTools.createJavaProcessBuilder(runJava.toArray(new String[0])).start();

        result = getJVMOptions(new InputStreamReader(p.getInputStream()), withRanges, acceptOrigin);

        p.waitFor();

        return result;

    }

    /**

     * Get JVM options as list. Can return options with defined ranges or

     * options without range depending on "withRanges" argument. "acceptOrigin"

     * predicate can be used to filter option origin.

     *

     * @param withRanges true if needed options with defined ranges inside JVM

     * @param acceptOrigin predicate for option origins. Origins can be

     * "product", "diagnostic" etc. Accept option only if acceptOrigin evaluates

     * to true.

     * @param additionalArgs additional arguments to the Java process which ran

     * with "-XX:+PrintFlagsRanges"

     * @return List of options

     * @throws Exception if a new process can not be created or an error

     * occurred while reading the data

     */

    public static List<JVMOption> getOptions(boolean withRanges, Predicate<String> acceptOrigin,

            String... additionalArgs) throws Exception {

        return new ArrayList<>(getOptionsAsMap(withRanges, acceptOrigin, additionalArgs).values());

    }

    /**

     * Get JVM options with ranges as list. "acceptOrigin" predicate can be used

     * to filter option origin.

     *

     * @param acceptOrigin predicate for option origins. Origins can be

     * "product", "diagnostic" etc. Accept option only if acceptOrigin evaluates

     * to true.

     * @param additionalArgs additional arguments to the Java process which ran

     * with "-XX:+PrintFlagsRanges"

     * @return List of options

     * @throws Exception if a new process can not be created or an error

     * occurred while reading the data

     */

    public static List<JVMOption> getOptionsWithRange(Predicate<String> acceptOrigin, String... additionalArgs) throws Exception {

        return getOptions(true, acceptOrigin, additionalArgs);

    }

    /**

     * Get JVM options with ranges as list.

     *

     * @param additionalArgs additional arguments to the Java process which ran

     * with "-XX:+PrintFlagsRanges"

     * @return list of options

     * @throws Exception if a new process can not be created or an error

     * occurred while reading the data

     */

    public static List<JVMOption> getOptionsWithRange(String... additionalArgs) throws Exception {

        return getOptionsWithRange(origin -> true, additionalArgs);

    }

    /**

     * Get JVM options with range as map. "acceptOrigin" predicate can be used

     * to filter option origin.

     *

     * @param acceptOrigin predicate for option origins. Origins can be

     * "product", "diagnostic" etc. Accept option only if acceptOrigin evaluates

     * to true.

     * @param additionalArgs additional arguments to the Java process which ran

     * with "-XX:+PrintFlagsRanges"

     * @return Map from option name to the JVMOption object

     * @throws Exception if a new process can not be created or an error

     * occurred while reading the data

     */

    public static Map<String, JVMOption> getOptionsWithRangeAsMap(Predicate<String> acceptOrigin, String... additionalArgs) throws Exception {

        return getOptionsAsMap(true, acceptOrigin, additionalArgs);

    }

    /**

     * Get JVM options with range as map

     *

     * @param additionalArgs additional arguments to the Java process which ran

     * with "-XX:+PrintFlagsRanges"

     * @return map from option name to the JVMOption object

     * @throws Exception if a new process can not be created or an error

     * occurred while reading the data

     */

    public static Map<String, JVMOption> getOptionsWithRangeAsMap(String... additionalArgs) throws Exception {

        return getOptionsWithRangeAsMap(origin -> true, additionalArgs);

    }

    /* Simple method to test that java start-up. Used for testing options. */

    public static void main(String[] args) {

        System.out.print("Java start-up!");

    }

}