/*
    * 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.util.sort;
  
  import fr.paris.lutece.portal.service.util.AppLogService;
  
  import java.io.Serializable;
  
  import java.lang.reflect.InvocationTargetException;
  import java.lang.reflect.Method;
  
  import java.util.Comparator;
  import java.util.Locale;
  
  /**
   * This class provide Attribute Comparator
   */
  public class AttributeComparator implements Comparator<Object>, Serializable
  {
      private static final long serialVersionUID = 8552197766086300259L;
      private String _strSortedAttribute;
      private boolean _bIsASC;
  
      /**
       * Constructor
       * 
       * @param strSortedAttribute
       *            the name of the attribute on which the sort will be made
       * @param bIsASC
       *            true for the ASC order, false for the DESC order
       */
      public AttributeComparator( String strSortedAttribute, boolean bIsASC )
      {
          _strSortedAttribute = strSortedAttribute;
          _bIsASC = bIsASC;
      }
  
      /**
       * Constructor
       * 
       * @param strSortedAttribute
       *            the name of the attribute on which the sort will be made
       */
      public AttributeComparator( String strSortedAttribute )
      {
          _strSortedAttribute = strSortedAttribute;
          _bIsASC = true;
      }
  
      /**
       * Compare two objects o1 and o2.
       * 
       * @param o1
       *            Object
       * @param o2
       *            Object
       * @return &lt; 0 if o1 is before o2 in the alphabetical order 0 if o1 equals o2 &gt; 0 if o1 is after o2
       */
      @Override
      public int compare( Object o1, Object o2 )
      {
          int nStatus = 0;
  
          Method method1 = getMethod( o1 );
          Method method2 = getMethod( o2 );
  
          if ( method1 == null || method2 == null || method1.getReturnType( ) != method2.getReturnType( ) )
          {
             return 0;
         }
 
         try
         {
             nStatus = compareReturnTypes( o1, o2, method1, method2 );
         }
         catch( IllegalArgumentException | IllegalAccessException | InvocationTargetException e )
         {
             AppLogService.error( e.getMessage( ), e );
         }
 
         if ( !_bIsASC )
         {
             nStatus = nStatus * ( -1 );
         }
 
         return nStatus;
     }
 
     private int compareReturnTypes( Object o1, Object o2, Method method1, Method method2 ) throws IllegalAccessException, InvocationTargetException
     {
         int nStatus = 0;
         Object oRet1 = method1.invoke( o1 );
         Object oRet2 = method2.invoke( o2 );
 
         String strReturnType = method1.getReturnType( ).getName( );
         Class<?> returnType = method1.getReturnType( );
 
         if ( oRet1 == null )
         {
             if ( oRet2 == null )
             {
                 nStatus = 0;
             }
             else
             {
                 nStatus = -1;
             }
         }
         else
         {
             if ( oRet2 == null )
             {
                 nStatus = 1;
             }
             else
             {
                 if ( strReturnType.equals( "java.lang.String" ) )
                 {
                     nStatus = ( (String) oRet1 ).toLowerCase( Locale.ENGLISH ).compareTo( ( (String) oRet2 ).toLowerCase( Locale.ENGLISH ) );
                 }
                 else
                     if ( returnType.isPrimitive( ) || isComparable( returnType ) )
                     {
                         nStatus = ( (Comparable) oRet1 ).compareTo( (Comparable) oRet2 );
                     }
                     else
                         if ( returnType.isEnum( ) )
                         {
                             nStatus = oRet1.toString( ).compareTo( oRet2.toString( ) );
                         }
             }
         }
 
         return nStatus;
     }
 
     /**
      * Return the getter method of the object obj for the attribute _strSortedAttribute
      * 
      * @param obj
      *            the object
      * @return method Method of the object obj for the attribute _strSortedAttribute
      */
     private Method getMethod( Object obj )
     {
         Method method = null;
         String strFirstLetter = _strSortedAttribute.substring( 0, 1 ).toUpperCase( );
 
         String strMethodName = "get" + strFirstLetter + _strSortedAttribute.substring( 1, _strSortedAttribute.length( ) );
 
         try
         {
             method = obj.getClass( ).getMethod( strMethodName );
         }
         catch( Exception e )
         {
             AppLogService.error( e.getMessage( ), e );
         }
 
         return method;
     }
 
     /**
      * Returns <code>true</code> if the class implements {@link Comparable} or extends a super class that implements {@link Comparable}, <code>false</code>
      * otherwise.
      * 
      * @param clazz
      *            the class
      * @return <code>true</code> if the class implements {@link Comparable}, <code>false</code> otherwise.
      */
     private boolean isComparable( Class<?> clazz )
     {
         for ( Class<?> interfac : clazz.getInterfaces( ) )
         {
             if ( interfac.equals( Comparable.class ) )
             {
                 return true;
             }
         }
 
         // The class might be extending a super class that implements {@link Comparable}
         Class<?> superClass = clazz.getSuperclass( );
 
         if ( superClass != null )
         {
             return isComparable( superClass );
         }
 
         return false;
     }
 }