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1   /*
2    * Copyright (c) 2002-2022, City of Paris
3    * All rights reserved.
4    *
5    * Redistribution and use in source and binary forms, with or without
6    * modification, are permitted provided that the following conditions
7    * are met:
8    *
9    *  1. Redistributions of source code must retain the above copyright notice
10   *     and the following disclaimer.
11   *
12   *  2. Redistributions in binary form must reproduce the above copyright notice
13   *     and the following disclaimer in the documentation and/or other materials
14   *     provided with the distribution.
15   *
16   *  3. Neither the name of 'Mairie de Paris' nor 'Lutece' nor the names of its
17   *     contributors may be used to endorse or promote products derived from
18   *     this software without specific prior written permission.
19   *
20   * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
21   * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
22   * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
23   * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDERS OR CONTRIBUTORS BE
24   * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
25   * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
26   * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
27   * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
28   * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
29   * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
30   * POSSIBILITY OF SUCH DAMAGE.
31   *
32   * License 1.0
33   */
34  package fr.paris.lutece.portal.web.l10n;
35  
36  import fr.paris.lutece.portal.service.datastore.DatastoreService;
37  import fr.paris.lutece.portal.service.util.AppLogService;
38  import fr.paris.lutece.portal.service.util.AppPropertiesService;
39  import java.util.ArrayList;
40  import java.util.List;
41  
42  import java.util.Locale;
43  
44  import javax.servlet.http.HttpServletRequest;
45  import javax.servlet.http.HttpSession;
46  
47  /**
48   * LocaleService
49   */
50  public final class LocaleService
51  {
52      private static final String ATTRIBUTE_SELECTED_LOCALE = "LUTECE_ATTRIBUTE_USER_SELECTED_LOCALE";
53      private static final String DSKEY_LANGUAGE_DEFAULT = "portal.site.site_property.locale.default";
54      private static final String PROPERTY_LANG_LIST = "lutece.i18n.availableLocales";
55      private static final String PROPERTY_LANG_DEFAULT = "lutece.i18n.defaultLocale";
56      private static Locale _locale;
57      private static List<Locale> _supportedLocales;
58  
59      /**
60       * Private constructor
61       */
62      private LocaleService( )
63      {
64      }
65  
66      /**
67       * Set the locale selected by the user in the front office. The user may select a language without been authenticated.
68       * 
69       * @param request
70       *            The request
71       * @param locale
72       *            The locale
73       */
74      public static void setUserSelectedLocale( HttpServletRequest request, Locale locale )
75      {
76          HttpSession session = request.getSession( true );
77          session.setAttribute( ATTRIBUTE_SELECTED_LOCALE, locale );
78      }
79  
80      /**
81       * Get a Locale selected by the user in front office
82       * 
83       * @param request
84       *            The HTTP request
85       * @return The locale selected, or the default jvm locale if no locale has been selected
86       */
87      public static Locale getUserSelectedLocale( HttpServletRequest request )
88      {
89          Locale locale = LocaleService.getDefault( );
90          HttpSession session = request.getSession( );
91  
92          if ( session != null )
93          {
94              Locale localeSession = (Locale) session.getAttribute( ATTRIBUTE_SELECTED_LOCALE );
95  
96              if ( localeSession != null )
97              {
98                  locale = localeSession;
99              }
100         }
101 
102         return locale;
103     }
104 
105     /**
106      * Return a Lutece defined default Locale
107      * 
108      * @return The locale
109      */
110     public static synchronized Locale getDefault( )
111     {
112         if ( _locale != null )
113         {
114             return _locale;
115         }
116         else
117         {
118             String dsLang = DatastoreService.getInstanceDataValue( DSKEY_LANGUAGE_DEFAULT, null );
119 
120             if ( dsLang != null )
121             {
122                 for ( String strISOLang : Locale.getISOLanguages( ) )
123                 {
124                     if ( strISOLang.equals( dsLang ) )
125                     {
126                         _locale = new Locale( dsLang );
127                         AppLogService.info( "LocaleService : default locale set to : {}", dsLang );
128 
129                         return _locale;
130                     }
131                 }
132             }
133 
134             // otherwise, get the default locale from properties
135             _locale = new Locale( AppPropertiesService.getProperty( PROPERTY_LANG_DEFAULT ) );
136             AppLogService.error( "LocaleService : invalid defined locale {} - default set to {}", dsLang, _locale.getLanguage( ) );
137 
138             return _locale;
139         }
140     }
141 
142     /**
143      * Retrieve the best supported locale for the user's session Priority order : 1- selected locale session attribute 2- browser locale (if supported) 3-
144      * default server locale
145      * 
146      * @param request
147      *            The HTTP request
148      * @return The locale
149      */
150     public static Locale getContextUserLocale( HttpServletRequest request )
151     {
152         // consider the current session locale
153         if ( request != null )
154         {
155             HttpSession session = request.getSession( false );
156             if ( session != null )
157             {
158                 Locale userSessionLocale = (Locale) session.getAttribute( ATTRIBUTE_SELECTED_LOCALE );
159                 if ( userSessionLocale != null )
160                 {
161                     if ( isSupported( userSessionLocale ) )
162                     {
163                         return userSessionLocale;
164                     }
165                 }
166             }
167         }
168 
169         // consider the browser language
170         Locale locale = new Locale( request.getLocale( ).getLanguage( ).substring( 0, 2 ) );
171         if ( isSupported( locale ) )
172         {
173             return locale;
174         }
175 
176         // otherwise consider the server default
177         return getDefault( );
178     }
179 
180     /**
181      * check if Locale is supported according to locale list in lutece properties
182      * 
183      * @param locale
184      * @return true if supported
185      */
186     public static boolean isSupported( Locale locale )
187     {
188         if ( _supportedLocales == null )
189         {
190             getSupportedLangList( );
191         }
192 
193         // check if the mandatory language is supported
194         for ( Locale supportedLocale : _supportedLocales )
195         {
196             if ( supportedLocale.equals( locale ) )
197             {
198                 return true;
199             }
200         }
201 
202         return false;
203     }
204 
205     /**
206      * get Supported Lang List
207      * 
208      * @return the Supported Lang List
209      */
210     public static synchronized List<Locale> getSupportedLangList( )
211     {
212         if ( _supportedLocales == null )
213         {
214             String [ ] strLangList = AppPropertiesService.getProperty( PROPERTY_LANG_LIST ).split( "," );
215             _supportedLocales = new ArrayList<>( );
216             for ( String lang : strLangList )
217             {
218                 _supportedLocales.add( new Locale( lang ) );
219             }
220         }
221 
222         return _supportedLocales;
223     }
224 }