001// License: GPL. For details, see LICENSE file.
002package org.openstreetmap.josm.tools;
003
004import java.util.Collection;
005import java.util.LinkedList;
006import java.util.Locale;
007
008public final class LanguageInfo {
009
010    private LanguageInfo() {
011        // Hide default constructor for utils classes
012    }
013
014    /**
015     * Type of the locale to use
016     * @since 5915
017     */
018    public enum LocaleType {
019        /** The current default language */
020        DEFAULT,
021        /** The current default language, but not english */
022        DEFAULTNOTENGLISH,
023        /** The base language (i.e. pt for pt_BR) */
024        BASELANGUAGE,
025        /** The standard english texts */
026        ENGLISH
027    }
028
029    /**
030     * Replies the wiki language prefix for the given locale. The wiki language
031     * prefix has the form 'Xy:' where 'Xy' is a ISO 639 language code in title
032     * case (or Xy_AB: for sub languages).
033     *
034     * @param type the type
035     * @return the wiki language prefix or {@code null} for {@link LocaleType#BASELANGUAGE}, when
036     * base language is identical to default or english
037     * @since 5915
038     */
039    public static String getWikiLanguagePrefix(LocaleType type) {
040        if (type == LocaleType.ENGLISH)
041          return "";
042
043        String code = getJOSMLocaleCode();
044        if (type == LocaleType.BASELANGUAGE) {
045            if (code.matches("[^_]+_[^_]+")) {
046                code = code.substring(0, 2);
047                if ("en".equals(code))
048                    return null;
049            } else {
050                return null;
051            }
052        } else if (type == LocaleType.DEFAULTNOTENGLISH && "en".equals(code)) {
053            return null;
054        } else if (code.matches(".+@.+")) {
055          return code.substring(0, 1).toUpperCase(Locale.ENGLISH) + code.substring(1, 2)
056          + '-' + code.substring(3, 4).toUpperCase(Locale.ENGLISH) + code.substring(4) + ':';
057        }
058        return code.substring(0, 1).toUpperCase(Locale.ENGLISH) + code.substring(1) + ':';
059    }
060
061    /**
062     * Replies the wiki language prefix for the current locale.
063     *
064     * @return the wiki language prefix
065     * @see Locale#getDefault()
066     * @see #getWikiLanguagePrefix(LocaleType)
067     */
068    public static String getWikiLanguagePrefix() {
069        return getWikiLanguagePrefix(LocaleType.DEFAULT);
070    }
071
072    /**
073     * Replies the JOSM locale code for the default locale.
074     *
075     * @return the JOSM locale code for the default locale
076     * @see #getJOSMLocaleCode(Locale)
077     */
078    public static String getJOSMLocaleCode() {
079        return getJOSMLocaleCode(Locale.getDefault());
080    }
081
082    /**
083     * Replies the locale code used by JOSM for a given locale.
084     *
085     * In most cases JOSM uses the 2-character ISO 639 language code ({@link Locale#getLanguage()}
086     * to identify the locale of a localized resource, but in some cases it may use the
087     * programmatic name for locales, as replied by {@link Locale#toString()}.
088     *
089     * For unknown country codes and variants this function already does fallback to
090     * internally known translations.
091     *
092     * @param locale the locale. Replies "en" if null.
093     * @return the JOSM code for the given locale
094     */
095    public static String getJOSMLocaleCode(Locale locale) {
096        if (locale == null) return "en";
097        for (String full : getLanguageCodes(locale)) {
098            if ("iw_IL".equals(full))
099                return "he";
100            else if ("in".equals(full))
101                return "id";
102            else if (I18n.hasCode(full)) // catch all non-single codes
103                return full;
104        }
105
106        // return single code as fallback
107        return locale.getLanguage();
108    }
109
110    /**
111     * Replies the locale code used by Java for a given locale.
112     *
113     * In most cases JOSM and Java uses the same codes, but for some exceptions this is needed.
114     *
115     * @param localeName the locale. Replies "en" if null.
116     * @return the Java code for the given locale
117     * @since 8232
118     */
119    public static String getJavaLocaleCode(String localeName) {
120        if (localeName == null) return "en";
121        if ("ca@valencia".equals(localeName)) {
122            localeName = "ca__valencia";
123        } else if ("he".equals(localeName)) {
124            localeName = "iw_IL";
125        } else if ("id".equals(localeName)) {
126            localeName = "in";
127        }
128        return localeName;
129    }
130
131    /**
132     * Replies the display string used by JOSM for a given locale.
133     *
134     * In most cases returns text replied by {@link Locale#getDisplayName()}, for some
135     * locales an override is used (i.e. when unsupported by Java).
136     *
137     * @param locale the locale. Replies "en" if null.
138     * @return the display string for the given locale
139     * @since 8232
140     */
141    public static String getDisplayName(Locale locale) {
142        return locale.getDisplayName();
143    }
144
145    /**
146     * Replies the locale used by Java for a given language code.
147     *
148     * Accepts JOSM and Java codes as input.
149     *
150     * @param localeName the locale code.
151     * @return the resulting locale
152     */
153    public static Locale getLocale(String localeName) {
154        int country = localeName.indexOf('_');
155        int variant = localeName.indexOf('@');
156        if (variant < 0 && country >= 0)
157            variant = localeName.indexOf('_', country+1);
158        Locale l;
159        if (variant > 0 && country > 0) {
160            l = new Locale(localeName.substring(0, country), localeName.substring(country+1, variant), localeName.substring(variant + 1));
161        } else if (variant > 0) {
162            l = new Locale(localeName.substring(0, variant), "", localeName.substring(variant + 1));
163        } else if (country > 0) {
164            l = new Locale(localeName.substring(0, country), localeName.substring(country + 1));
165        } else {
166            l = new Locale(localeName);
167        }
168        return l;
169    }
170
171    /**
172     * Check if a new language is better than a previous existing. Can be used in classes where
173     * multiple user supplied language marked strings appear and the best one is searched. Following
174     * priorities: current language, english, any other
175     *
176     * @param oldLanguage the language code of the existing string
177     * @param newLanguage the language code of the new string
178     * @return true if new one is better
179     * @since 8091
180     */
181    public static boolean isBetterLanguage(String oldLanguage, String newLanguage) {
182        if (oldLanguage == null)
183            return true;
184        String want = getJOSMLocaleCode();
185        return want.equals(newLanguage) || (!want.equals(oldLanguage) && newLanguage.startsWith("en"));
186    }
187
188    /**
189     * Replies the language prefix for use in XML elements (with a dot appended).
190     *
191     * @return the XML language prefix
192     * @see #getJOSMLocaleCode()
193     */
194    public static String getLanguageCodeXML() {
195        String code = getJOSMLocaleCode();
196        code = code.replace('@', '-');
197        return code+'.';
198    }
199
200    /**
201     * Replies the language prefix for use in manifests (with an underscore appended).
202     *
203     * @return the manifest language prefix
204     * @see #getJOSMLocaleCode()
205     */
206    public static String getLanguageCodeManifest() {
207        String code = getJOSMLocaleCode();
208        code = code.replace('@', '-');
209        return code+'_';
210    }
211
212    /**
213     * Replies a list of language codes for local names. Prefixes range from very specific
214     * to more generic.
215     * <ul>
216     *   <li>lang_COUNTRY@variant  of the current locale</li>
217     *   <li>lang@variant  of the current locale</li>
218     *   <li>lang_COUNTRY of the current locale</li>
219     *   <li>lang of the current locale</li>
220     * </ul>
221     *
222     * @param l the locale to use, <code>null</code> for default locale
223     * @return list of codes
224     * @since 8283
225     */
226    public static Collection<String> getLanguageCodes(Locale l) {
227        Collection<String> list = new LinkedList<String>();
228        if (l == null)
229            l = Locale.getDefault();
230        String lang = l.getLanguage();
231        String c = l.getCountry();
232        String v = l.getVariant();
233        if (c.isEmpty())
234            c = null;
235        if (v != null && !v.isEmpty()) {
236            if (c != null)
237                list.add(lang+'_'+c+'@'+v);
238            list.add(lang+'@'+v);
239        }
240        if (c != null)
241            list.add(lang+'_'+c);
242        list.add(lang);
243        return list;
244    }
245}