/*
    * Copyright (c) 2002-2022, City of 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.resource.service;
  
  import fr.paris.lutece.plugins.resource.business.IResource;
  import fr.paris.lutece.plugins.resource.business.IResourceType;
  import fr.paris.lutece.plugins.resource.service.provider.IResourceProvider;
  import fr.paris.lutece.portal.service.spring.SpringContextService;
  
  import java.util.ArrayList;
  import java.util.List;
  
  /**
   * Resource service
   */
  public class ResourceService
  {
      private static final String BEAN_NAME = "resource.resourceService";
      private static volatile ResourceService _instance;
  
      /**
       * Default constructor
       */
      private ResourceService( )
      {
          // Private constructor
      }
  
      /**
       * Get the instance of the service
       * 
       * @return The instance of the service
       */
      public static ResourceService getInstance( )
      {
          if ( _instance == null )
          {
              _instance = SpringContextService.getBean( BEAN_NAME );
          }
  
          return _instance;
      }
  
      /**
       * Get the list of available resource types
       * 
       * @return The list of available resource types
       */
      public List<IResourceType> getResourceTypesList( )
      {
          String strCacheKey = ResourceCacheService.getResourceTypesListCacheKey( );
          List<IResourceType> listResourceTypes = (List<IResourceType>) ResourceCacheService.getInstance( ).getFromCache( strCacheKey );
  
          if ( listResourceTypes != null )
          {
              return listResourceTypes;
          }
  
          listResourceTypes = new ArrayList<>( );
  
          for ( IResourceProvider provider : SpringContextService.getBeansOfType( IResourceProvider.class ) )
          {
              listResourceTypes.addAll( provider.getResourceTypeList( ) );
          }
  
          ResourceCacheService.getInstance( ).putInCache( strCacheKey, listResourceTypes );
  
          return listResourceTypes;
     }
 
     /**
      * Check if a resource type is managed by any provider
      * 
      * @param strResourceTypeName
      *            The resource type
      * @return True if the resource type is managed by any provider, false otherwise
      */
     public boolean isResourceTypeManaged( String strResourceTypeName )
     {
         return getResourceProvider( strResourceTypeName ) != null;
     }
 
     /**
      * Declare a resource type as created. This method is used to keep cache up to date.
      * 
      * @param strResourceTypeName
      *            The created resource type
      */
     public void resourceTypeCreated( String strResourceTypeName )
     {
         ResourceCacheService.getInstance( ).removeKey( ResourceCacheService.getResourceTypesListCacheKey( ) );
     }
 
     /**
      * Declare a resource type as removed. This method is used to keep cache up to date.
      * 
      * @param strResourceTypeName
      *            The removed resource type
      */
     public void resourceTypeRemoved( String strResourceTypeName )
     {
         ResourceCacheService.getInstance( ).removeKey( ResourceCacheService.getResourceTypeProviderCacheKey( strResourceTypeName ) );
         ResourceCacheService.getInstance( ).removeKey( ResourceCacheService.getResourceTypesListCacheKey( ) );
     }
 
     /**
      * Get a resource from its id and type
      * 
      * @param strIdResource
      *            the id of the resource to get
      * @param strResourceTypeName
      *            the type of the resource to get
      * @return The resource, or null if the resource could not be found
      */
     public IResource getResource( String strIdResource, String strResourceTypeName )
     {
         IResourceProvider provider = getResourceProvider( strResourceTypeName );
 
         if ( provider != null )
         {
             return provider.getResource( strIdResource, strResourceTypeName );
         }
 
         return null;
     }
 
     /**
      * Get the list of resources of a given type
      * 
      * @param strResourceTypeName
      *            the resource type
      * @return the list of resource of the given type, or an empty list if not resource was found
      */
     public List<IResource> getListResources( String strResourceTypeName )
     {
         IResourceProvider resourceProvider = getResourceProvider( strResourceTypeName );
 
         if ( resourceProvider != null )
         {
             return resourceProvider.getListResources( strResourceTypeName );
         }
 
         return new ArrayList<>( 0 );
     }
 
     /**
      * Get the resource provider of a resource type
      * 
      * @param strResourceTypeName
      *            The resource provider of a resource type
      * @return The resource provider, or null if no provider was found for the given resource type
      */
     public IResourceProvider getResourceProvider( String strResourceTypeName )
     {
         String strCacheKey = ResourceCacheService.getResourceTypeProviderCacheKey( strResourceTypeName );
         IResourceProvider./../fr/paris/lutece/plugins/resource/service/provider/IResourceProvider.html#IResourceProvider">IResourceProvider provider = (IResourceProvider) ResourceCacheService.getInstance( ).getFromCache( strCacheKey );
 
         if ( provider != null )
         {
             return provider;
         }
 
         for ( IResourceProvider resourceProvider : SpringContextService.getBeansOfType( IResourceProvider.class ) )
         {
             if ( resourceProvider.isResourceTypeManaged( strResourceTypeName ) )
             {
                 ResourceCacheService.getInstance( ).putInCache( strCacheKey, resourceProvider );
 
                 return resourceProvider;
             }
         }
 
         return null;
     }
 }