/*

 * Copyright (c) 2017, 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 org.graalvm.compiler.hotspot;

import static jdk.vm.ci.common.InitTimer.timer;

import java.io.File;

import java.io.FileReader;

import java.io.IOException;

import java.util.Map;

import java.util.Properties;

import org.graalvm.compiler.options.Option;

import org.graalvm.compiler.options.OptionDescriptors;

import org.graalvm.compiler.options.OptionKey;

import org.graalvm.compiler.options.OptionValues;

import org.graalvm.compiler.options.OptionValuesAccess;

import org.graalvm.compiler.options.OptionsParser;

import org.graalvm.compiler.serviceprovider.ServiceProvider;

import jdk.vm.ci.common.InitTimer;

/**

 * The {@link #HOTSPOT_OPTIONS} value contains the options values initialized in a HotSpot VM. The

 * values are set via system properties with the {@value #GRAAL_OPTION_PROPERTY_PREFIX} prefix.

 */

@ServiceProvider(OptionValuesAccess.class)

public class HotSpotGraalOptionValues implements OptionValuesAccess {

    /**

     * The name of the system property specifying a file containing extra Graal option settings.

     */

    private static final String GRAAL_OPTIONS_FILE_PROPERTY_NAME = "graal.options.file";

    /**

     * The name of the system property specifying the Graal version.

     */

    private static final String GRAAL_VERSION_PROPERTY_NAME = "graal.version";

    /**

     * The prefix for system properties that correspond to {@link Option} annotated fields. A field

     * named {@code MyOption} will have its value set from a system property with the name

     * {@code GRAAL_OPTION_PROPERTY_PREFIX + "MyOption"}.

     */

    public static final String GRAAL_OPTION_PROPERTY_PREFIX = "graal.";

    /**

     * Gets the system property assignment that would set the current value for a given option.

     */

    public static String asSystemPropertySetting(OptionValues options, OptionKey<?> value) {

        return GRAAL_OPTION_PROPERTY_PREFIX + value.getName() + "=" + value.getValue(options);

    }

    public static final OptionValues HOTSPOT_OPTIONS = initializeOptions();

    /**

     * Global options. The values for these options are initialized by parsing the file denoted by

     * the {@code VM.getSavedProperty(String) saved} system property named

     * {@value #GRAAL_OPTIONS_FILE_PROPERTY_NAME} if the file exists followed by parsing the options

     * encoded in saved system properties whose names start with

     * {@value #GRAAL_OPTION_PROPERTY_PREFIX}. Key/value pairs are parsed from the aforementioned

     * file with {@link Properties#load(java.io.Reader)}.

     */

    @SuppressWarnings("try")

    private static OptionValues initializeOptions() {

        EconomicMap<OptionKey<?>, Object> values = OptionValues.newOptionMap();

        try (InitTimer t = timer("InitializeOptions")) {

            Iterable<OptionDescriptors> loader = OptionsParser.getOptionsLoader();

            Map<String, String> savedProps = jdk.vm.ci.services.Services.getSavedProperties();

            String optionsFile = savedProps.get(GRAAL_OPTIONS_FILE_PROPERTY_NAME);

            if (optionsFile != null) {

                File graalOptions = new File(optionsFile);

                if (graalOptions.exists()) {

                    try (FileReader fr = new FileReader(graalOptions)) {

                        Properties props = new Properties();

                        props.load(fr);

                        EconomicMap<String, String> optionSettings = EconomicMap.create();

                        for (Map.Entry<Object, Object> e : props.entrySet()) {

                            optionSettings.put((String) e.getKey(), (String) e.getValue());

                        }

                        try {

                            OptionsParser.parseOptions(optionSettings, values, loader);

                        } catch (Throwable e) {

                            throw new InternalError("Error parsing an option from " + graalOptions, e);

                        }

                    } catch (IOException e) {

                        throw new InternalError("Error reading " + graalOptions, e);

                    }

                }

            }

            EconomicMap<String, String> optionSettings = EconomicMap.create();

            for (Map.Entry<String, String> e : savedProps.entrySet()) {

                String name = e.getKey();

                if (name.startsWith(GRAAL_OPTION_PROPERTY_PREFIX)) {

                    if (name.equals("graal.PrintFlags") || name.equals("graal.ShowFlags")) {

                        System.err.println("The " + name + " option has been removed and will be ignored. Use -XX:+JVMCIPrintProperties instead.");

                    } else if (name.equals(GRAAL_OPTIONS_FILE_PROPERTY_NAME) || name.equals(GRAAL_VERSION_PROPERTY_NAME)) {

                        // Ignore well known properties that do not denote an option

                    } else {

                        String value = e.getValue();

                        optionSettings.put(name.substring(GRAAL_OPTION_PROPERTY_PREFIX.length()), value);

                    }

                }

            }

            OptionsParser.parseOptions(optionSettings, values, loader);

            return new OptionValues(values);

        }

    }

    @Override

    public OptionValues getOptions() {

        return HOTSPOT_OPTIONS;

    }

}