/*
 * This program is free software; you can redistribute it and/or modify it under the
 * terms of the GNU Lesser General Public License, version 2.1 as published by the Free Software
 * Foundation.
 *
 * You should have received a copy of the GNU Lesser General Public License along with this
 * program; if not, you can obtain a copy at http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html
 * or from the Free Software Foundation, Inc.,
 * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
 *
 * This program 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.
 *
 * Copyright (c) 2000 - 2009 Pentaho Corporation, Object Refinery Limited and Contributors.  All rights reserved.
 */

package org.pentaho.reporting.libraries.pixie.wmf.records;

import java.awt.Point;

import org.pentaho.reporting.libraries.pixie.wmf.MfDcState;
import org.pentaho.reporting.libraries.pixie.wmf.MfRecord;
import org.pentaho.reporting.libraries.pixie.wmf.MfType;
import org.pentaho.reporting.libraries.pixie.wmf.WmfFile;

/**
 * Moves the current Viewport Origin to the specified position
 */
public class MfCmdOffsetViewportOrg extends MfCmd
{
  private static final int RECORD_SIZE = 2;
  private static final int POS_X = 1;
  private static final int POS_Y = 0;

  private int x;
  private int y;

  private int scaled_x;
  private int scaled_y;

  public MfCmdOffsetViewportOrg()
  {
  }

  /**
   * Replays the command on the given WmfFile.
   *
   * @param file the meta file.
   */
  public void replay(final WmfFile file)
  {
    final MfDcState state = file.getCurrentState();
    final Point p = getScaledDestination();
    state.setViewportOrg
        (state.getViewportOrgX() + p.x,
            state.getViewportOrgY() + p.y);
  }

  /**
   * Creates a empty unintialized copy of this command implementation.
   *
   * @return a new instance of the command.
   */
  public MfCmd getInstance()
  {
    return new MfCmdOffsetViewportOrg();
  }

  public Point getDestination()
  {
    return new Point(x, y);
  }

  public String toString()
  {
    final StringBuffer b = new StringBuffer();
    b.append("[OFFSET_VIEWPORT] destination=");
    b.append(getDestination());
    return b.toString();
  }

  public void setDestination(final int x, final int y)
  {
    this.x = x;
    this.y = y;
    scaleXChanged();
    scaleYChanged();

  }

  public void setDestination(final Point p)
  {
    setDestination(p.x, p.y);
  }

  /**
   * Reads the function identifier. Every record type is identified by a function number
   * corresponding to one of the Windows GDI functions used.
   *
   * @return the function identifier.
   */
  public int getFunction()
  {
    return MfType.OFFSET_VIEWPORT_ORG;
  }

  /**
   * Reads the command data from the given record and adjusts the internal parameters
   * according to the data parsed.
   * <p/>
   * After the raw record was read from the datasource, the record is parsed by the
   * concrete implementation.
   *
   * @param record the raw data that makes up the record.
   */
  public void setRecord(final MfRecord record)
  {
    final int y = record.getParam(POS_Y);
    final int x = record.getParam(POS_X);
    setDestination(x, y);
  }

  /**
   * Creates a new record based on the data stored in the MfCommand.
   *
   * @return the created record.
   */
  public MfRecord getRecord()
  {
    final Point dest = getDestination();
    final MfRecord record = new MfRecord(RECORD_SIZE);
    record.setParam(POS_Y, dest.y);
    record.setParam(POS_X, dest.x);
    return record;
  }

  public Point getScaledDestination()
  {
    return new Point(scaled_x, scaled_y);
  }

  /**
   * A callback function to inform the object, that the x scale has changed and the
   * internal coordinate values have to be adjusted.
   */
  protected void scaleXChanged()
  {
    scaled_x = getScaledX(x);
  }

  /**
   * A callback function to inform the object, that the y scale has changed and the
   * internal coordinate values have to be adjusted.
   */
  protected void scaleYChanged()
  {
    scaled_y = getScaledY(y);
  }

}
