/*
 * file:       ExtendedData.java
 * author:     Jon Iles
 * copyright:  (c) Packwood Software 2002-2003
 * date:       23/05/2003
 */

/*
 * 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.
 */

package net.sf.mpxj.mpp;

import java.io.PrintWriter;
import java.io.StringWriter;
import java.util.Date;
import java.util.HashMap;

/**
 * This class represents the extended data structure which is used to
 * hold additional non-core data items associated with tasks and resources.
 */
final class ExtendedData
{
   /**
    * Constructor. Given the var data block, and the offset of the extended
    * data block within the var data, the constructor extracts each data item
    * of extended data and inserts it into a Map using it's type as the key.
    *
    * @param varData Var data block
    * @param offset Offset of extended data within the var data block
    */
   ExtendedData(FixDeferFix varData, int offset)
   {
      m_data = varData;
      byte[] data = varData.getByteArray(offset);

      if (data != null)
      {
         int index = 0;
         int size;
         int type;

         while (index < data.length)
         {
            size = MPPUtility.getInt(data, index);
            index += 4;

            type = MPPUtility.getInt(data, index);
            index += 4;

            m_map.put(Integer.valueOf(type), MPPUtility.cloneSubArray(data, index, size));
            index += size;
         }
      }
   }

   /**
    * Retrieves a string value from the extended data.
    *
    * @param type Type identifier
    * @return string value
    */
   public String getString(Integer type)
   {
      String result = null;

      byte[] item = m_map.get(type);
      if (item != null)
      {
         result = m_data.getString(getOffset(item));
      }

      return (result);
   }

   /**
    * Retrieves a string value from the extended data.
    *
    * @param type Type identifier
    * @return string value
    */
   public String getUnicodeString(Integer type)
   {
      String result = null;

      byte[] item = m_map.get(type);
      if (item != null)
      {
         result = m_data.getUnicodeString(getOffset(item));
      }

      return (result);
   }

   /**
    * Retrieves a short int value from the extended data.
    *
    * @param type Type identifier
    * @return short int value
    */
   public int getShort(Integer type)
   {
      int result = 0;

      byte[] item = m_map.get(type);
      if (item != null)
      {
         result = MPPUtility.getShort(item, 0);
      }

      return (result);
   }

   /**
    * Retrieves an integer value from the extended data.
    *
    * @param type Type identifier
    * @return integer value
    */
   public int getInt(Integer type)
   {
      int result = 0;

      byte[] item = m_map.get(type);
      if (item != null)
      {
         result = MPPUtility.getInt(item, 0);
      }

      return (result);
   }

   /**
    * Retrieves a long value from the extended data.
    *
    * @param type Type identifier
    * @return long value
    */
   public long getLong(Integer type)
   {
      long result = 0;

      byte[] item = m_map.get(type);
      if (item != null)
      {
         result = MPPUtility.getLong6(item, 0);
      }

      return (result);
   }

   /**
    * Retrieves a double value from the extended data.
    *
    * @param type Type identifier
    * @return double value
    */
   public double getDouble(Integer type)
   {
      double result = 0;

      byte[] item = m_map.get(type);
      if (item != null)
      {
         result = MPPUtility.getDouble(item, 0);
      }

      return (result);
   }

   /**
    * Retrieves a timestamp from the extended data.
    *
    * @param type Type identifier
    * @return timestamp
    */
   public Date getTimestamp(Integer type)
   {
      Date result = null;

      byte[] item = m_map.get(type);
      if (item != null)
      {
         result = MPPUtility.getTimestamp(item, 0);
      }

      return (result);
   }

   /**
    * Retrieve the raw byte array.
    * 
    * @param type data type
    * @return byte array
    */
   public byte[] getByteArray(Integer type)
   {
      return (m_map.get(type));
   }

   /**
    * Convert an integer into an offset.
    *
    * @param data four byte integer value
    * @return offset value
    */
   private int getOffset(byte[] data)
   {
      return (-1 - MPPUtility.getInt(data, 0));
   }

   /**
    * Used for debugging. Outputs the contents of the extended data
    * block as a formatted string.
    *
    * @return string representation of extended data block
    */
   @Override public String toString()
   {
      StringWriter sw = new StringWriter();
      PrintWriter pw = new PrintWriter(sw);

      pw.println("BEGIN ExtendedData");

      for (Integer type : m_map.keySet())
      {
         byte[] item = m_map.get(type);
         pw.println("Type: " + type + " Data:" + MPPUtility.hexdump(item, false));
      }

      pw.println("END ExtendedData");
      pw.println();
      pw.close();

      return (sw.toString());
   }

   private FixDeferFix m_data;
   private HashMap<Integer, byte[]> m_map = new HashMap<Integer, byte[]>();
}