/*

 * Copyright (c) 2010, 2011, 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

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

 * questions.

 */

/*

 *******************************************************************************

 * Copyright (C) 2009-2010, International Business Machines Corporation and    *

 * others. All Rights Reserved.                                                *

 *******************************************************************************

 */

package sun.util.locale;

import java.lang.ref.SoftReference;

import java.util.StringJoiner;

public final class BaseLocale {

    public static final String SEP = "_";

    private static final Cache CACHE = new Cache();

    private final String language;

    private final String script;

    private final String region;

    private final String variant;

    private volatile int hash;

    // This method must be called only when creating the Locale.* constants.

    private BaseLocale(String language, String region) {

        this.language = language;

        this.script = "";

        this.region = region;

        this.variant = "";

    }

    private BaseLocale(String language, String script, String region, String variant) {

        this.language = (language != null) ? LocaleUtils.toLowerString(language).intern() : "";

        this.script = (script != null) ? LocaleUtils.toTitleString(script).intern() : "";

        this.region = (region != null) ? LocaleUtils.toUpperString(region).intern() : "";

        this.variant = (variant != null) ? variant.intern() : "";

    }

    // Called for creating the Locale.* constants. No argument

    // validation is performed.

    public static BaseLocale createInstance(String language, String region) {

        BaseLocale base = new BaseLocale(language, region);

        CACHE.put(new Key(language, region), base);

        return base;

    }

    public static BaseLocale getInstance(String language, String script,

                                         String region, String variant) {

        // JDK uses deprecated ISO639.1 language codes for he, yi and id

        if (language != null) {

            if (LocaleUtils.caseIgnoreMatch(language, "he")) {

                language = "iw";

            } else if (LocaleUtils.caseIgnoreMatch(language, "yi")) {

                language = "ji";

            } else if (LocaleUtils.caseIgnoreMatch(language, "id")) {

                language = "in";

            }

        }

        Key key = new Key(language, script, region, variant);

        BaseLocale baseLocale = CACHE.get(key);

        return baseLocale;

    }

    public String getLanguage() {

        return language;

    }

    public String getScript() {

        return script;

    }

    public String getRegion() {

        return region;

    }

    public String getVariant() {

        return variant;

    }

    @Override

    public boolean equals(Object obj) {

        if (this == obj) {

            return true;

        }

        if (!(obj instanceof BaseLocale)) {

            return false;

        }

        BaseLocale other = (BaseLocale)obj;

        return language == other.language

               && script == other.script

               && region == other.region

               && variant == other.variant;

    }

    @Override

    public String toString() {

        StringJoiner sj = new StringJoiner(", ");

        if (language.length() > 0) {

            sj.add("language=" + language);

        }

        if (script.length() > 0) {

            sj.add("script=" + script);

        }

        if (region.length() > 0) {

            sj.add("region=" + region);

        }

        if (variant.length() > 0) {

            sj.add("variant=" + variant);

        }

        return sj.toString();

    }

    @Override

    public int hashCode() {

        int h = hash;

        if (h == 0) {

            // Generating a hash value from language, script, region and variant

            h = language.hashCode();

            h = 31 * h + script.hashCode();

            h = 31 * h + region.hashCode();

            h = 31 * h + variant.hashCode();

            if (h != 0) {

                hash = h;

            }

        }

        return h;

    }

    private static final class Key {

        private final SoftReference<String> lang;

        private final SoftReference<String> scrt;

        private final SoftReference<String> regn;

        private final SoftReference<String> vart;

        private final boolean normalized;

        private final int hash;

        /**

         * Creates a Key. language and region must be normalized

         * (intern'ed in the proper case).

         */

        private Key(String language, String region) {

            assert language.intern() == language

                   && region.intern() == region;

            lang = new SoftReference<>(language);

            scrt = new SoftReference<>("");

            regn = new SoftReference<>(region);

            vart = new SoftReference<>("");

            this.normalized = true;

            int h = language.hashCode();

            if (region != "") {

                int len = region.length();

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

                    h = 31 * h + LocaleUtils.toLower(region.charAt(i));

                }

            }

            hash = h;

        }

        public Key(String language, String script, String region, String variant) {

            this(language, script, region, variant, false);

        }

        private Key(String language, String script, String region,

                    String variant, boolean normalized) {

            int h = 0;

            if (language != null) {

                lang = new SoftReference<>(language);

                int len = language.length();

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

                    h = 31*h + LocaleUtils.toLower(language.charAt(i));

                }

            } else {

                lang = new SoftReference<>("");

            }

            if (script != null) {

                scrt = new SoftReference<>(script);

                int len = script.length();

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

                    h = 31*h + LocaleUtils.toLower(script.charAt(i));

                }

            } else {

                scrt = new SoftReference<>("");

            }

            if (region != null) {

                regn = new SoftReference<>(region);

                int len = region.length();

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

                    h = 31*h + LocaleUtils.toLower(region.charAt(i));

                }

            } else {

                regn = new SoftReference<>("");

            }

            if (variant != null) {

                vart = new SoftReference<>(variant);

                int len = variant.length();

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

                    h = 31*h + variant.charAt(i);

                }

            } else {

                vart = new SoftReference<>("");

            }

            hash = h;

            this.normalized = normalized;

        }

        @Override

        public boolean equals(Object obj) {

            if (this == obj) {

                return true;

            }

            if (obj instanceof Key && this.hash == ((Key)obj).hash) {

                String tl = this.lang.get();

                String ol = ((Key)obj).lang.get();

                if (tl != null && ol != null &&

                    LocaleUtils.caseIgnoreMatch(ol, tl)) {

                    String ts = this.scrt.get();

                    String os = ((Key)obj).scrt.get();

                    if (ts != null && os != null &&

                        LocaleUtils.caseIgnoreMatch(os, ts)) {

                        String tr = this.regn.get();

                        String or = ((Key)obj).regn.get();

                        if (tr != null && or != null &&

                            LocaleUtils.caseIgnoreMatch(or, tr)) {

                            String tv = this.vart.get();

                            String ov = ((Key)obj).vart.get();

                            return (ov != null && ov.equals(tv));

                        }

                    }

                }

            }

            return false;

        }

        @Override

        public int hashCode() {

            return hash;

        }

        public static Key normalize(Key key) {

            if (key.normalized) {

                return key;

            }

            String lang = LocaleUtils.toLowerString(key.lang.get()).intern();

            String scrt = LocaleUtils.toTitleString(key.scrt.get()).intern();

            String regn = LocaleUtils.toUpperString(key.regn.get()).intern();

            String vart = key.vart.get().intern(); // preserve upper/lower cases

            return new Key(lang, scrt, regn, vart, true);

        }

    }

    private static class Cache extends LocaleObjectCache<Key, BaseLocale> {

        public Cache() {

        }

        @Override

        protected Key normalizeKey(Key key) {

            assert key.lang.get() != null &&

                   key.scrt.get() != null &&

                   key.regn.get() != null &&

                   key.vart.get() != null;

            return Key.normalize(key);

        }

        @Override

        protected BaseLocale createObject(Key key) {

            return new BaseLocale(key.lang.get(), key.scrt.get(),

                                  key.regn.get(), key.vart.get());

        }

    }

}