/* Distributed under the Apache License, Version 2.0.
   See accompanying NOTICE file for details.*/
package com.kitware.physiology.utilities;

import java.lang.reflect.Field;
import java.util.*;


public class SimpleEquals
{
  public static boolean Equals(Object A, Object B)
  {
    if(A==null && B==null)
      return true;
    if(A.getClass() != B.getClass())
    {
      Log.error("Classes are not the same type");
      return false;
    }
    
    List<Field> fieldList = new ArrayList<Field>();
    Class<?> tmpClass = A.getClass();
    while (tmpClass != null) 
    {
        fieldList.addAll(Arrays.asList(tmpClass.getDeclaredFields()));
        tmpClass = tmpClass .getSuperclass();
    }
  
    for(Field f : fieldList)
    {      
      try
      {
        f.setAccessible(true);
        Object a = f.get(A);
        Object b = f.get(B);
        
        Log.info("Comparing "+f.getName());
        
        if(a==null && b==null)
          continue;
        if( (a==null && b!=null) || (a!=null && b==null))
        {
          Log.error(f.getName()+" is only present in " + (a==null?"B":"A"));
          return false;
        }
        
        
        if(f.getType().isPrimitive() || f.getType() == String.class || f.isEnumConstant())
        {
          if(!a.equals(b))
          {
            Log.error("A "+f.get(A) +" != B "+f.get(B));
            return false;
          }
        }
        else if(List.class.isAssignableFrom(f.getType()))
        {
          List<?> aList = (List<?>) a;
          List<?> bList = (List<?>) b;
          if(aList.size() != bList.size())
          {
            Log.error(f.getName()+" list sizes are not the same ");
            return false;
          }
          for(int i=0; i<aList.size(); i++)
          {
            if(!Equals(aList.get(i),bList.get(i)))
              return false;
          }
        }
        else
        {
          Log.info("Comparing "+a.getClass().getSimpleName());
          if(!Equals(a,b))
            return false;
        }                
      } 
      catch (IllegalArgumentException e)
      {
        // TODO Auto-generated catch block
        e.printStackTrace();
      } 
      catch (IllegalAccessException e)
      {
        // TODO Auto-generated catch block
        e.printStackTrace();
      }      
    }    
    return true;
  }
}
