/*
    * Copyright (c) 2002-2017, Mairie de Paris
    * All rights reserved.
    *
    * Redistribution and use in source and binary forms, with or without
    * modification, are permitted provided that the following conditions
    * are met:
    *
    *  1. Redistributions of source code must retain the above copyright notice
   *     and the following disclaimer.
   *
   *  2. Redistributions in binary form must reproduce the above copyright notice
   *     and the following disclaimer in the documentation and/or other materials
   *     provided with the distribution.
   *
   *  3. Neither the name of 'Mairie de Paris' nor 'Lutece' nor the names of its
   *     contributors may be used to endorse or promote products derived from
   *     this software without specific prior written permission.
   *
   * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
   * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
   * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
   * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDERS OR CONTRIBUTORS BE
   * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
   * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
   * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
   * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
   * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
   * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
   * POSSIBILITY OF SUCH DAMAGE.
   *
   * License 1.0
   */
  package fr.paris.lutece.plugins.chatbot.web;
  
  import fr.paris.lutece.plugins.chatbot.business.BotDescription;
  import fr.paris.lutece.plugins.chatbot.service.bot.ChatBot;
  import fr.paris.lutece.plugins.chatbot.business.Post;
  import fr.paris.lutece.plugins.chatbot.service.BotService;
  import static fr.paris.lutece.plugins.chatbot.service.BotService.getBots;
  import fr.paris.lutece.plugins.chatbot.service.ChatService;
  import fr.paris.lutece.portal.service.util.AppPathService;
  import fr.paris.lutece.portal.service.util.AppPropertiesService;
  import fr.paris.lutece.portal.util.mvc.commons.annotations.Action;
  import fr.paris.lutece.portal.util.mvc.commons.annotations.View;
  import fr.paris.lutece.portal.util.mvc.xpage.MVCApplication;
  import fr.paris.lutece.portal.util.mvc.xpage.annotations.Controller;
  import fr.paris.lutece.portal.web.l10n.LocaleService;
  import fr.paris.lutece.portal.web.xpages.XPage;
  import fr.paris.lutece.util.url.UrlItem;
  
  import java.util.ArrayList;
  import java.util.HashMap;
  import java.util.List;
  import java.util.Locale;
  import java.util.Map;
  import java.util.UUID;
  
  import javax.servlet.http.HttpServletRequest;
  
  /**
   * This class provides a simple implementation of an XPage
   */
  @Controller( xpageName = "chatbot", pageTitleI18nKey = "chatbot.xpage.bot.pageTitle", pagePathI18nKey = "chatbot.xpage.bot.pagePathLabel" )
  public class ChatBotApp extends MVCApplication
  {
      private static final String TEMPLATE_BOT = "/skin/plugins/chatbot/bot.html";
      private static final String TEMPLATE_BOT_STANDALONE = "/skin/plugins/chatbot/bot_standalone.html";
      private static final String TEMPLATE_BOTS_LIST = "/skin/plugins/chatbot/bots_list.html";
      private static final String MARK_BOTS_LIST = "bots_list";
      private static final String MARK_POSTS_LIST = "posts_list";
      private static final String MARK_BOT_AVATAR = "bot_avatar";
      private static final String MARK_BASE_URL = "base_url";
      private static final String MARK_BOT = "bot";
      private static final String MARK_LANGUAGE = "language";
      private static final String MARK_STANDALONE = "standalone";
      private static final String MARK_TYPED_SCRIPT = "typed_script";
      private static final String PARAMETER_BOT = "bot";
      private static final String PARAMETER_RESPONSE = "response";
      private static final String PARAMETER_LANGUAGE = "lang";
      private static final String PARAMETER_STANDALONE = "standalone";
      private static final String PARAMETER_BUTTON_VALUE = "button_value";
      private static final String VIEW_LIST = "list";
      private static final String VIEW_BOT = "bot";
      private static final String ACTION_RESPONSE = "response";
      private static final String ACTION_BUTTON_RESPONSE = "button_click";
      private static final String URL_BOT = "jsp/site/Portal.jsp?page=chatbot&view=bot";
      private static final String PROPERTY_STANDALONE = "chatbot.standalone";
      private static final String PROPERTY_TYPED_SCRIPT = "chatbot.typed_script.enabled";
      
      private static final boolean DEFAULT_TYPED_SCRIPT = true;
  
      private static final long serialVersionUID = 1L;
  
      private String _strBotKey;
      private Locale _locale;
      private String _strConversationId;
      private ChatBot _bot;
      private boolean _bStandalone;
 
     /**
      * Returns the content of the list of bots page
      * 
      * @param request
      *            The HTTP request
      * @return The page
      */
     @View( value = VIEW_LIST, defaultView = true )
     public XPage viewList( HttpServletRequest request )
     {
         List<BotDescription> listBots = getBotsDescription( );
 
         Map<String, Object> model = getModel( );
         model.put( MARK_BOTS_LIST, listBots );
 
         return getXPage( TEMPLATE_BOTS_LIST, request.getLocale( ), model );
     }
 
     /**
      * Returns the content of the bot page.
      * 
      * @param request
      *            The HTTP request
      * @return The page
      */
     @View( VIEW_BOT )
     public XPage viewBot( HttpServletRequest request )
     {
         String strBotKey = request.getParameter( PARAMETER_BOT );
         if ( strBotKey == null )
         {
             // assuming the bot is the current session bot
             if ( _strBotKey == null )
             {
                 // session is closed
                 return redirectView( request, VIEW_LIST );
             }
         }
         else
         {
             if ( !strBotKey.equals( _strBotKey ) )
             {
                 // new bot or bot has changed
                 initSessionParameters( request, strBotKey );
             }
         }
         boolean bTypedScript = AppPropertiesService.getPropertyBoolean( PROPERTY_TYPED_SCRIPT , DEFAULT_TYPED_SCRIPT );
         List<Post> listPosts = ChatService.getConversation( _strConversationId, _bot, _locale );
         Map<String, Object> model = getModel( );
         model.put( MARK_POSTS_LIST, listPosts );
         model.put( MARK_BOT_AVATAR, _bot.getAvatarUrl( ) );
         model.put( MARK_BASE_URL, AppPathService.getBaseUrl( request ) );
         model.put( MARK_BOT, _strBotKey );
         model.put( MARK_LANGUAGE, _locale.getLanguage( ) );
         model.put( MARK_STANDALONE, ( _bStandalone ) ? "true" : "false" );
         model.put(  MARK_TYPED_SCRIPT , bTypedScript );
 
         String strTemplate = ( _bStandalone ) ? TEMPLATE_BOT_STANDALONE : TEMPLATE_BOT;
         XPage xpage = getXPage( strTemplate, request.getLocale( ), model );
         xpage.setTitle( _bot.getName( _locale ) );
         xpage.setPathLabel( _bot.getName( _locale ) );
         xpage.setStandalone( _bStandalone );
 
         return xpage;
     }
 
     /**
      * Process the response
      * 
      * @param request
      *            The HTTP request
      * @return The redirected page
      */
     @Action( ACTION_RESPONSE )
     public XPage doProcessMessage( HttpServletRequest request )
     {
         if ( !checkSession( request ) )
         {
             return redirectView( request, VIEW_LIST );
         }
 
         String strMessage = request.getParameter( PARAMETER_RESPONSE );
 
         ChatService.processMessage( request, _strConversationId, strMessage, _strBotKey, _locale );
         Map<String, String> mapParameters = new HashMap<>( );
         mapParameters.put( PARAMETER_BOT, _strBotKey );
         mapParameters.put( PARAMETER_LANGUAGE, _locale.getLanguage( ) );
         mapParameters.put( PARAMETER_STANDALONE, _bStandalone ? "true" : "false" );
 
         return redirect( request, VIEW_BOT, mapParameters );
     }
 
     /**
      * Process Button click
      * 
      * @param request
      *            The HTTP request
      * @return The redirected page
      */
     @Action( ACTION_BUTTON_RESPONSE )
     public XPage doProcessButtonMessage( HttpServletRequest request )
     {
         if ( !checkSession( request ) )
         {
             return redirectView( request, VIEW_LIST );
         }
 
         String strMessage = request.getParameter( PARAMETER_BUTTON_VALUE );
 
         ChatService.processMessage( request, _strConversationId, strMessage, _strBotKey, _locale );
         Map<String, String> mapParameters = new HashMap<>( );
         mapParameters.put( PARAMETER_BOT, _strBotKey );
         mapParameters.put( PARAMETER_LANGUAGE, _locale.getLanguage( ) );
         mapParameters.put( PARAMETER_STANDALONE, _bStandalone ? "true" : "false" );
 
         return redirect( request, VIEW_BOT, mapParameters );
     }
 
     /**
      * Get request information for the bot language
      * 
      * @param request
      *            The request
      * @return The locale
      */
     private Locale getBotLocale( HttpServletRequest request )
     {
         String strLanguage = request.getParameter( PARAMETER_LANGUAGE );
 
         if ( strLanguage != null )
         {
             return new Locale( strLanguage );
         }
 
         return LocaleService.getDefault( );
     }
 
     /**
      * Gets the list of bots
      * 
      * @return The list of bots
      */
     private List<BotDescription> getBotsDescription( )
     {
         List<BotDescription> list = new ArrayList<BotDescription>( );
 
         for ( ChatBot bot : getBots( ) )
         {
             List<String> listLanguages = bot.getAvailableLanguages( );
 
             if ( listLanguages != null )
             {
                 for ( String strLanguage : listLanguages )
                 {
                     BotDescription botDescription = new BotDescription( );
                     Locale locale = new Locale( strLanguage );
                     botDescription.setName( bot.getName( locale ) );
                     botDescription.setDescription( bot.getDescription( locale ) );
                     botDescription.setLanguage( locale.getDisplayLanguage( ) );
                     botDescription.setAvatarUrl( bot.getAvatarUrl( ) );
 
                     UrlItem url = new UrlItem( URL_BOT );
                     url.addParameter( PARAMETER_BOT, bot.getKey( ) );
                     url.addParameter( PARAMETER_LANGUAGE, strLanguage );
                     botDescription.setUrl( url.getUrl( ) );
                     list.add( botDescription );
                 }
             }
             else
             {
                 BotDescription botDescription = new BotDescription( );
                 Locale locale = LocaleService.getDefault( );
                 botDescription.setName( bot.getName( locale ) );
                 botDescription.setDescription( bot.getDescription( locale ) );
                 botDescription.setLanguage( locale.getDisplayLanguage( ) );
                 UrlItem url = new UrlItem( URL_BOT );
                 url.addParameter( PARAMETER_BOT, bot.getKey( ) );
                 url.addParameter( PARAMETER_LANGUAGE, locale.getLanguage() );
                 botDescription.setUrl( url.getUrl( ) );
                 list.add( botDescription );
             }
         }
 
         return list;
     }
 
     /**
      * Generate a Conversation ID
      * 
      * @return The ID
      */
     private String getNewConversationId( )
     {
         return UUID.randomUUID( ).toString( );
     }
 
     /**
      * Gets the running mode according configuration and runtime parameters
      * 
      * @param request
      *            The HTTP request
      * @return true if the current bit should be run in standalone mode
      */
     private boolean getStandalone( HttpServletRequest request )
     {
         String strStandalone = request.getParameter( PARAMETER_STANDALONE );
         if ( strStandalone != null && ( strStandalone.equalsIgnoreCase( "true" ) || strStandalone.equalsIgnoreCase( "on" ) ) )
         {
             return true;
         }
         strStandalone = AppPropertiesService.getProperty( PROPERTY_STANDALONE );
         if ( strStandalone != null && ( strStandalone.equalsIgnoreCase( "true" ) || strStandalone.equalsIgnoreCase( "on" ) ) )
         {
             return true;
         }
         return false;
     }
 
     /**
      * Check the session
      * 
      * @param request
      *            The HTTP request
      * @return true if the bot session is active or can be restarted otherwise false
      */
     private boolean checkSession( HttpServletRequest request )
     {
         if ( _strBotKey == null )
         {
             String strBotKey = request.getParameter( PARAMETER_BOT );
             if ( strBotKey != null )
             {
                 initSessionParameters( request, strBotKey );
             }
             else
             {
                 return false;
             }
         }
         return true;
     }
 
     /**
      * Initialize session datas
      * 
      * @param request
      *            The request
      * @param strBotKey
      *            The bot key
      */
     private void initSessionParameters( HttpServletRequest request, String strBotKey )
     {
         _strBotKey = strBotKey;
         _bot = BotService.getBot( _strBotKey );
         _locale = getBotLocale( request );
         _strConversationId = getNewConversationId( );
         _bStandalone = ( _bot.isStandalone( ) ) ? true : getStandalone( request );
     }
 }