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 * Copyright (c) 2012, 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 sun.util.locale.provider;

import static java.util.Calendar.*;

import java.util.Comparator;

import java.util.Locale;

import java.util.Map;

import java.util.Set;

import java.util.TreeMap;

import java.util.spi.CalendarNameProvider;

import sun.util.calendar.CalendarSystem;

import sun.util.calendar.Era;

/**

 * Concrete implementation of the {@link java.util.spi.CalendarNameProvider

 * CalendarNameProvider} class for the JRE LocaleProviderAdapter.

 *

 * @author Masayoshi Okutsu

 * @author Naoto Sato

 */

public class CalendarNameProviderImpl extends CalendarNameProvider implements AvailableLanguageTags {

    protected final LocaleProviderAdapter.Type type;

    protected final Set<String> langtags;

    public CalendarNameProviderImpl(LocaleProviderAdapter.Type type, Set<String> langtags) {

        this.type = type;

        this.langtags = langtags;

    }

    @Override

    public String getDisplayName(String calendarType, int field, int value, int style, Locale locale) {

        return getDisplayNameImpl(calendarType, field, value, style, locale, false);

    }

    public String getJavaTimeDisplayName(String calendarType, int field, int value, int style, Locale locale) {

        return getDisplayNameImpl(calendarType, field, value, style, locale, true);

    }

    public String getDisplayNameImpl(String calendarType, int field, int value, int style, Locale locale, boolean javatime) {

        String name = null;

        String key = getResourceKey(calendarType, field, style, javatime);

        if (key != null) {

            LocaleResources lr = LocaleProviderAdapter.forType(type).getLocaleResources(locale);

            String[] strings = javatime ? lr.getJavaTimeNames(key) : lr.getCalendarNames(key);

            // If standalone names are requested and no "standalone." resources are found,

            // try the default ones instead.

            if (strings == null && key.indexOf("standalone.") != -1) {

                key = key.replaceFirst("standalone.", "");

                strings = javatime ? lr.getJavaTimeNames(key) : lr.getCalendarNames(key);

            }

            if (strings != null && strings.length > 0) {

                if (field == DAY_OF_WEEK || field == YEAR) {

                    --value;

                }

                if (value < 0) {

                    return null;

                } else if (value >= strings.length) {

                    if (field == ERA && "japanese".equals(calendarType)) {

                        Era[] jeras = CalendarSystem.forName("japanese").getEras();

                        if (value <= jeras.length) {

                            // Localized era name could not be retrieved from this provider.

                            // This can occur either for NewEra or SupEra.

                            //

                            // If it's CLDR provider, try COMPAT first, which is guaranteed to have

                            // the name for NewEra.

                            if (type == LocaleProviderAdapter.Type.CLDR) {

                                lr = LocaleProviderAdapter.forJRE().getLocaleResources(locale);

                                key = getResourceKeyFor(LocaleProviderAdapter.Type.JRE,

                                                calendarType, field, style, javatime);

                                strings =

                                    javatime ? lr.getJavaTimeNames(key) : lr.getCalendarNames(key);

                            }

                            if (strings == null || value >= strings.length) {

                                // Get the default name for SupEra

                                Era supEra = jeras[value - 1]; // 0-based index

                                if (javatime) {

                                    return getBaseStyle(style) == NARROW_FORMAT ?

                                        supEra.getAbbreviation() :

                                        supEra.getName();

                                } else {

                                    return (style & LONG) != 0 ?

                                        supEra.getName() :

                                        supEra.getAbbreviation();

                                }

                            }

                        } else {

                            return null;

                        }

                    } else {

                        return null;

                    }

                }

                name = strings[value];

                // If name is empty in standalone, try its `format' style.

                        && (style == SHORT_STANDALONE || style == LONG_STANDALONE

                            || style == NARROW_STANDALONE)) {

                    name = getDisplayName(calendarType, field, value,

                                          getBaseStyle(style),

                                          locale);

                }

            }

        }

        return name;

    }

    private static int[] REST_OF_STYLES = {

        SHORT_STANDALONE, LONG_FORMAT, LONG_STANDALONE,

        NARROW_FORMAT, NARROW_STANDALONE

    };

    @Override

    public Map<String, Integer> getDisplayNames(String calendarType, int field, int style, Locale locale) {

        Map<String, Integer> names;

        if (style == ALL_STYLES) {

            names = getDisplayNamesImpl(calendarType, field, SHORT_FORMAT, locale, false);

            for (int st : REST_OF_STYLES) {

                names.putAll(getDisplayNamesImpl(calendarType, field, st, locale, false));

            }

        } else {

            // specific style

            names = getDisplayNamesImpl(calendarType, field, style, locale, false);

        }

        return names.isEmpty() ? null : names;

    }

    // NOTE: This method should be used ONLY BY JSR 310 classes.

    public Map<String, Integer> getJavaTimeDisplayNames(String calendarType, int field, int style, Locale locale) {

        Map<String, Integer> names;

        names = getDisplayNamesImpl(calendarType, field, style, locale, true);

        return names.isEmpty() ? null : names;

    }

    private Map<String, Integer> getDisplayNamesImpl(String calendarType, int field,

                                                     int style, Locale locale, boolean javatime) {

        String key = getResourceKey(calendarType, field, style, javatime);

        Map<String, Integer> map = new TreeMap<>(LengthBasedComparator.INSTANCE);

        if (key != null) {

            LocaleResources lr = LocaleProviderAdapter.forType(type).getLocaleResources(locale);

            String[] strings = javatime ? lr.getJavaTimeNames(key) : lr.getCalendarNames(key);

            // If standalone names are requested and no "standalone." resources are found,

            // try the default ones instead.

            if (strings == null && key.indexOf("standalone.") != -1) {

                key = key.replaceFirst("standalone.", "");

                strings = javatime ? lr.getJavaTimeNames(key) : lr.getCalendarNames(key);

            }

            if (strings != null) {

                if (!hasDuplicates(strings)) {

                    if (field == YEAR) {

                        if (strings.length > 0) {

                            map.put(strings[0], 1);

                        }

                    } else {

                        int base = (field == DAY_OF_WEEK) ? 1 : 0;

                        for (int i = 0; i < strings.length; i++) {

                            String name = strings[i];

                            // Ignore any empty string (some standalone month names

                            // are not defined)

                                continue;

                            }

                            map.put(name, base + i);

                        }

                    }

                }

            }

        }

        return map;

    }

    private static int getBaseStyle(int style) {

        return style & ~(SHORT_STANDALONE - SHORT_FORMAT);

    }

    /**

     * Comparator implementation for TreeMap which iterates keys from longest

     * to shortest.

     */

    private static class LengthBasedComparator implements Comparator<String> {

        private static final LengthBasedComparator INSTANCE = new LengthBasedComparator();

        private LengthBasedComparator() {

        }

        @Override

        public int compare(String o1, String o2) {

            int n = o2.length() - o1.length();

            return (n == 0) ? o1.compareTo(o2) : n;

        }

    }

    @Override

    public Locale[] getAvailableLocales() {

        return LocaleProviderAdapter.toLocaleArray(langtags);

    }

    @Override

    public boolean isSupportedLocale(Locale locale) {

        if (Locale.ROOT.equals(locale)) {

            return true;

        }

        String calendarType = null;

        if (locale.hasExtensions()) {

            calendarType = locale.getUnicodeLocaleType("ca");

            locale = locale.stripExtensions();

        }

        if (calendarType != null) {

            switch (calendarType) {

            case "buddhist":

            case "japanese":

            case "gregory":

            case "islamic":

            case "roc":

                break;

            default:

                // Unknown calendar type

                return false;

            }

        }

        if (langtags.contains(locale.toLanguageTag())) {

            return true;

        }

        String oldname = locale.toString().replace('_', '-');

        return langtags.contains(oldname);

    }

    @Override

    public Set<String> getAvailableLanguageTags() {

        return langtags;

    }

    private boolean hasDuplicates(String[] strings) {

        int len = strings.length;

        for (int i = 0; i < len - 1; i++) {

            String a = strings[i];

            if (a != null) {

                for (int j = i + 1; j < len; j++) {

                    if (a.equals(strings[j]))  {

                        return true;

                    }

                }

            }

        }

        return false;

    }

    private String getResourceKey(String type, int field, int style, boolean javatime) {

        return getResourceKeyFor(this.type, type, field, style, javatime);

    }

    private static String getResourceKeyFor(LocaleProviderAdapter.Type adapterType,

                            String type, int field, int style, boolean javatime) {

        int baseStyle = getBaseStyle(style);

        boolean isStandalone = (style != baseStyle);

        if ("gregory".equals(type)) {

            type = null;

        }

        boolean isNarrow = (baseStyle == NARROW_FORMAT);

        StringBuilder key = new StringBuilder();

        // If javatime is true, use prefix "java.time.".

        if (javatime) {

            key.append("java.time.");

        }

        switch (field) {

        case ERA:

            if (type != null) {

                key.append(type).append('.');

            }

            if (isNarrow) {

                key.append("narrow.");

            } else {

                // JRE and CLDR use different resource key conventions

                // due to historical reasons. (JRE DateFormatSymbols.getEras returns

                // abbreviations while other getShort*() return abbreviations.)

                if (adapterType == LocaleProviderAdapter.Type.JRE) {

                    if (javatime) {

                        if (baseStyle == LONG) {

                            key.append("long.");

                        }

                    }

                    if (baseStyle == SHORT) {

                        key.append("short.");

                    }

                } else { // this.type == LocaleProviderAdapter.Type.CLDR

                    if (baseStyle == LONG) {

                        key.append("long.");

                    }

                }

            }

            key.append("Eras");

            break;

        case YEAR:

            if (!isNarrow) {

                key.append(type).append(".FirstYear");

            }

            break;

        case MONTH:

            if ("islamic".equals(type)) {

                key.append(type).append('.');

            }

            if (isStandalone) {

                key.append("standalone.");

            }

            key.append("Month").append(toStyleName(baseStyle));

            break;

        case DAY_OF_WEEK:

            // support standalone day names

            if (isStandalone) {

                key.append("standalone.");

            }

            key.append("Day").append(toStyleName(baseStyle));

            break;

        case AM_PM:

            if (isNarrow) {

                key.append("narrow.");

            }

            key.append("AmPmMarkers");

            break;

        }

        return key.length() > 0 ? key.toString() : null;

    }

    private static String toStyleName(int baseStyle) {

        switch (baseStyle) {

        case SHORT:

            return "Abbreviations";

        case NARROW_FORMAT:

            return "Narrows";

        }

        return "Names";

    }

}