package com.hfg.util;

import java.io.ByteArrayInputStream;
import java.lang.reflect.Constructor;
import java.util.Collection;
import java.util.HashMap;
import java.util.List;
import java.util.Map;

import com.hfg.exception.ProgrammingException;
import com.hfg.util.collection.CollectionUtil;
import com.hfg.xml.HfgXML;
import com.hfg.xml.HfgXMLSerializable;
import com.hfg.xml.XMLNode;
import com.hfg.xml.XMLTag;
import com.hfg.xml.XMLizable;


//------------------------------------------------------------------------------
/**
 Generic attribute manager.
 <div>
 @author J. Alex Taylor, hairyfatguy.com
 </div>
 */
//------------------------------------------------------------------------------
// com.hfg XML/HTML Coding Library
//
// This library is free software; you can redistribute it and/or
// modify it under the terms of the GNU Lesser General Public
// License as published by the Free Software Foundation; either
// version 2.1 of the License, or (at your option) any later version.
//
// This library is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
// Lesser General Public License for more details.
//
// You should have received a copy of the GNU Lesser General Public
// License along with this library; if not, write to the Free Software
// Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
//
// J. Alex Taylor, President, Founder, CEO, COO, CFO, OOPS hairyfatguy.com
// jataylor@hairyfatguy.com
//------------------------------------------------------------------------------

public class AttributeMgr implements Cloneable, HfgXMLSerializable
{
   private Map<String, Object> mAttributes;


   //--------------------------------------------------------------------------
   public AttributeMgr()
   {
   }

   //--------------------------------------------------------------------------
   public AttributeMgr(XMLNode inXML)
   {
      inXML.verifyTagName(HfgXML.ATTRIBUTES);

      List<? extends XMLNode> attributeTags = inXML.getSubtagsByName(HfgXML.ATTRIBUTE);
      for (XMLNode attrTag : attributeTags)
      {
         String name = attrTag.getAttributeValue(HfgXML.NAME_ATT);
         String className = attrTag.getAttributeValue(HfgXML.CLASS_ATT);
         if (attrTag.getAttributeValue(HfgXML.IS_NULL_ATT) != null)
         {
            setAttribute(name, null);
         }
         else
         {
            String value = attrTag.getUnescapedContent();
            try
            {
               Class clazz = Class.forName(className);
               if (String.class.getName().equals(className))
               {
                  setAttribute(name, value);
               }
               else if (Integer.class.getName().equals(className))
               {
                  setAttribute(name, Integer.valueOf(value));
               }
               else if (Long.class.getName().equals(className))
               {
                  setAttribute(name, Long.valueOf(value));
               }
               else if (Float.class.getName().equals(className))
               {
                  setAttribute(name, Float.valueOf(value));
               }
               else if (Double.class.getName().equals(className))
               {
                  setAttribute(name, Double.valueOf(value));
               }
               else if (Boolean.class.getName().equals(className))
               {
                  setAttribute(name, Boolean.valueOf(value));
               }
               else
               {
                  try
                  {
                     Constructor constructor = clazz.getConstructor(XMLTag.class);
                     setAttribute(name, constructor.newInstance(new XMLTag(new ByteArrayInputStream(value.getBytes()))));
                  }
                  catch (NoSuchMethodException e)
                  {
                     Constructor constructor = clazz.getConstructor(String.class);
                     setAttribute(name, constructor.newInstance(value));
                  }
               }
            }
            catch (Exception e)
            {
               throw new RuntimeException("Problem extracting the value for attribute " + StringUtil.singleQuote(name) + "!", e);
            }
         }
      }
   }


   //--------------------------------------------------------------------------
   public AttributeMgr setAttribute(String inName, Object inValue)
   {
      if (null == mAttributes)
      {
         mAttributes = new HashMap<>();
      }

      mAttributes.put(inName, inValue);

      return this;
   }

   //--------------------------------------------------------------------------
   public boolean hasAttributes()
   {
      return CollectionUtil.hasValues(mAttributes);
   }

   //--------------------------------------------------------------------------
   public boolean hasAttribute(String inName)
   {
      return mAttributes != null && mAttributes.containsKey(inName);
   }

   //--------------------------------------------------------------------------
   public Object getAttribute(String inName)
   {
      Object attr = null;
      if (mAttributes != null)
      {
         attr = mAttributes.get(inName);
      }

      return attr;
   }

   //--------------------------------------------------------------------------
   public Collection<String> getAttributeNames()
   {
      Collection<String> attrNames = null;
      if (mAttributes != null)
      {
         attrNames = mAttributes.keySet();
      }

      return attrNames;
   }

   //--------------------------------------------------------------------------
   public void clearAttributes()
   {
      if (mAttributes != null)
      {
         mAttributes.clear();
      }
   }

   //--------------------------------------------------------------------------
   public Object removeAttribute(String inName)
   {
      Object attr = null;
      if (mAttributes != null)
      {
         attr  = mAttributes.remove(inName);
      }

      return attr;
   }

   //--------------------------------------------------------------------------
   public AttributeMgr clone()
   {
      AttributeMgr cloneObj;
      try
      {
         cloneObj = (AttributeMgr) super.clone();
      }
      catch (CloneNotSupportedException e)
      {
         throw new ProgrammingException(e);
      }

      if (mAttributes != null)
      {
         cloneObj.mAttributes = new HashMap<>(mAttributes.size());
         for (String key : mAttributes.keySet())
         {
            Object value = mAttributes.get(key);
            cloneObj.mAttributes.put(key, value != null ? value : null);
         }
      }

      return cloneObj;
   }


   //--------------------------------------------------------------------------
   public XMLNode toXMLNode()
   {
      XMLNode node = new XMLTag(HfgXML.ATTRIBUTES);

      for (String attrName : mAttributes.keySet())
      {
         XMLNode attributeTag = new XMLTag(HfgXML.ATTRIBUTE);
         attributeTag.setAttribute(HfgXML.NAME_ATT, attrName);

         Object value = mAttributes.get(attrName);
         if (value != null)
         {
            attributeTag.setAttribute(HfgXML.CLASS_ATT, value.getClass().getName());
            if (value instanceof XMLizable)
            {
               attributeTag.addContentWithoutEscaping(((XMLizable)value).toXML());
            }
            else
            {
               attributeTag.setContent(value.toString());
            }
         }
         else
         {
            attributeTag.setAttribute(HfgXML.IS_NULL_ATT, 1);
         }

         node.addSubtag(attributeTag);
      }

      return node;
   }

}