/* Copyright (c) 2005 Ricebridge. All Rights Reserved.
 *
 * This file is available under the terms and conditions of the
 * Ricebridge "Open Source API" policy; Ricebridge grants use of this
 * copyrighted work under the terms of a BSD-style license only. See
 * http://www.opensource.org/licenses/bsd-license.php for more
 * information.
 * 
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 
 *  - Redistributions of source code must retain the above copyright
 *  notice, this list of conditions and the following disclaimer.
 *
 *  - Redistributions in binary form must reproduce the above
 *  copyright notice, this list of conditions and the following
 *  disclaimer in the documentation and/or other materials provided
 *  with the distribution.
 *
 *  - Neither the name of the Ricebridge 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
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 * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
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 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
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 */

package com.ricebridge.xmlman;


import org.jostraca.util.Internal;
import org.jostraca.util.Standard;

import javax.swing.table.TableModel;

import java.util.*;


/** An implementation of {@link RecordProvider} that provides data records for saving
 *  from a {@link TableModel} object.
 *    <p>This class is used to implement the 
 *  {@link XmlManager#saveTableModel(File,RecordSpec,TableModel) saveTableModel(*,RecordSpec,TableModel)} 
 *  methods in {@link XmlManager}.
 *  It simply reads the next data record from the specified <code>TableModel</code>,
 *  maintaining an internal index of the current record.</p>
 *    <p><code>TableModelRecordProvider</code> is designed to be subclassed. You can change the default implementation by calling the 
 *  {@link com.ricebridge.xmlman.in.XmlManagerStoreBase#setTableModelRecordProviderClass setTableModelRecordProviderClass} method of 
 *  {@link com.ricebridge.xmlman.in.XmlManagerStore}, and providing a subclass of <code>TableModelRecordProvider</code>. 
 *  <code>XmlManagerStore</code> can be accessed using {@link XmlManager#getXmlManagerStore}.</p>
 *    <p>The <b><a href="TableModelRecordProvider.java.html">Source Code</a></b> of this Java class 
 *    is available under a <a href="http://www.opensource.org/licenses/bsd-license.php">BSD-style license</a>.</p>
 */
public class TableModelRecordProvider extends RecordProviderSupport {

  // public

  /** Output headers as first data record 
   *  (name for {@link XmlSpec#setProperty XmlSpec.setProperty}: <code>TableModel.saveHeaders</code>). */
  public static final String PROP_TableModel_saveHeaders = "TableModel.saveHeaders";


  // protected instance

  /** {@link TableModel} containing source data. */
  protected TableModel iTableModel = null;

  /** Save the table headers as first data record. See {@link #setXmlSpecImpl setXmlSpecImpl}. */
  protected boolean iSaveHeaders = false;

  /** Table headers. */
  protected String[] iHeaders = null;

  /** Indicate that internal state is at the first record. */ 
  protected boolean iFirstRecord = true;

  /** Number of data fields in record, determined by number of columns in table. */
  protected int iFieldCount = 0;

  /** Index of current record. */
  protected long iRecordIndex = 0;



  // constructors
  
  /** Create uninitialised for use with {@link #setTableModel setTableModel}. */
  public TableModelRecordProvider() {
    // init with setTableModel
  }


  /** Create initialised. See {@link #setTableModel setTableModel} for details. 
   *  @param pTableModel  <code>TableModel</code> providing data
   */
  public TableModelRecordProvider( TableModel pTableModel ) {
    setTableModel( pTableModel );
  }



  // public methods

  /** Set the <code>TableModel</code> providing data to save. 
   *    <p>The default number of fields per record is taken from 
   *  {@link TableModel#getColumnCount()}
   *  and the headers (output as the first record when the <code>TableModel.saveHeaders</code> property is true), 
   *  are taken from {@link TableModel#getColumnName(int)}. </p>
   *  @param pTableModel  <code>TableModel</code> providing data
   */
  public void setTableModel( TableModel pTableModel ) {
    iTableModel  = (TableModel) Internal.null_arg( pTableModel );

    iFieldCount  = iTableModel.getColumnCount();
    if( iSaveHeaders && 0 < iFieldCount ) {
      iHeaders = new String[ iFieldCount ];
      for( int cI = 0; cI < iFieldCount; cI++ ) {
        iHeaders[cI] = iTableModel.getColumnName( cI );
      }
    }
    else {
      iSaveHeaders = false;
    }
  }



  // RecordProviderSupport methods

  /** Handle property settings for saving {@link TableModel TableModels}.
   *    <p>You can change these using {@link XmlSpec}.</p>
   *  @see RecordListener#setXmlSpec
   *  @see #PROP_TableModel_saveHeaders
   */
  protected void setXmlSpecImpl( XmlSpec pXmlSpec ) {
    iSaveHeaders = pXmlSpec.getBooleanProperty( PROP_TableModel_saveHeaders );
  }


  /** Start the saving process. */
  protected void startProcessImpl() {
    iFirstRecord   = true;
    iRecordIndex   = 0;
  }


  /** Check if there are any more records. */
  protected boolean hasNextRecordImpl() {
    boolean hasNextRecord = false;
    if( iSaveHeaders && iFirstRecord ) {
      hasNextRecord = true;
    }
    else {
      hasNextRecord = ( iRecordIndex < iTableModel.getRowCount() );
    }

    return hasNextRecord;
  }


  /** Return next data record as a <code>String[]</code> array. */
  protected String[] nextRecordImpl() {
    String[] record = new String[iFieldCount];
    if( iSaveHeaders && iFirstRecord ) {
      for( int fI = 0; fI < iFieldCount; fI++ ) {
        record[fI] = iHeaders[ fI ];
      }
    }
    else {
      for( int fI = 0; fI < iFieldCount; fI++ ) {
        record[fI] = String.valueOf( iTableModel.getValueAt( (int) iRecordIndex, fI ) );
      }
      iRecordIndex++;
    }

    return record;
  }



}