import java.awt.*;
import java.awt.event.*;
import java.awt.image.*;
import java.util.*;
import java.awt.print.*;

import javax.swing.*;
import javax.swing.border.*;
import javax.swing.event.*;


public class PrintPreview extends JFrame implements Runnable
{
    protected JScrollPane displayArea;
    protected int m_wPage;
    protected int m_hPage;
    protected int width;
    protected int height;
    protected Printable m_target;
    protected JComboBox m_cbScale;
    protected PreviewContainer m_preview;
    protected PageFormat pp_pf = null;
    protected JButton formatButton;
    protected JButton shrinkButton;
    private static final int INCH = 72;
    private static boolean bScallToFitOnePage = false;

    protected void getThePreviewPages()
    {
        m_wPage = (int)(pp_pf.getWidth());
        m_hPage = (int)(pp_pf.getHeight());
        int scale = getDisplayScale();
        width = (int)Math.ceil(m_wPage*scale/100);
        height = (int)Math.ceil(m_hPage*scale/100);

        int pageIndex = 0;
        try {
          while (true) {
            BufferedImage img = new BufferedImage(m_wPage, m_hPage,
                                              BufferedImage.TYPE_INT_RGB);
            Graphics g = img.getGraphics();
            g.setColor(Color.white);
            g.fillRect(0, 0, m_wPage, m_hPage);
            if (bScallToFitOnePage) {
                m_target.print(g, pp_pf, -1);
                PagePreview pp = new PagePreview(width, height, img);
                m_preview.add(pp);
                break;
            } else
            if (m_target.print(g, pp_pf, pageIndex) !=  Printable.PAGE_EXISTS)
                break;
            PagePreview pp = new PagePreview(width, height, img);
            m_preview.add(pp);
            pageIndex++;
          }
        } catch (OutOfMemoryError om) {
            JOptionPane.showMessageDialog(this,
                "image is too big that run out of memory.", "Print Preview",
                JOptionPane.INFORMATION_MESSAGE);
        }
        catch (PrinterException e) {
            e.printStackTrace();
            System.err.println("Printing error: "+e.toString());
        }
    }

    protected void previewThePages(int orientation)
    {
        if (displayArea != null) displayArea.setVisible(false);

        m_preview = new PreviewContainer();

        getThePreviewPages();

        displayArea = new JScrollPane(m_preview);
        getContentPane().add(displayArea, BorderLayout.CENTER);
        setVisible(true);
        System.gc();
    }


    protected void createButtons(JToolBar tb, boolean shrink) {
        JButton bt = new JButton("Print", new ImageIcon("print.gif"));
        ActionListener lst = new ActionListener() {
          public void actionPerformed(ActionEvent e) {
            try {
                PrinterJob prnJob = PrinterJob.getPrinterJob();
                prnJob.setPrintable(m_target, pp_pf);
                if (prnJob.printDialog()) {
                    setCursor(Cursor.getPredefinedCursor(Cursor.WAIT_CURSOR));
                    prnJob.print();
                    setCursor(Cursor.getPredefinedCursor(Cursor.DEFAULT_CURSOR));
                }
                dispose();
            }
            catch (PrinterException ex) {
                ex.printStackTrace();
                System.err.println("Printing error: "+ex.toString());
            }
          }
        };
        bt.addActionListener(lst);
        bt.setAlignmentY(0.5f);
        bt.setMargin(new Insets(4,6,4,6));
        tb.add(bt);

        if (pp_pf.getOrientation() == PageFormat.PORTRAIT)
            formatButton = new JButton("Landscape");
        else
            formatButton = new JButton("Portrait");

        lst = new ActionListener() {
          public void actionPerformed(ActionEvent e) {
              if (pp_pf.getOrientation() == PageFormat.PORTRAIT) {
                pp_pf.setOrientation(PageFormat.LANDSCAPE);
                previewThePages(PageFormat.LANDSCAPE);
                formatButton.setText("Portrait");
              } else {
                pp_pf.setOrientation(PageFormat.PORTRAIT);
                previewThePages(PageFormat.PORTRAIT);
                formatButton.setText("Landscape");
              }
          }
        };
        formatButton.addActionListener(lst);
        formatButton.setAlignmentY(0.5f);
        formatButton.setMargin(new Insets(4,6,4,6));
        tb.add(formatButton);

        if (shrink) {
            shrinkButton = new JButton("Shrink to fit");

            lst = new ActionListener() {
              public void actionPerformed(ActionEvent e) {
                  bScallToFitOnePage = !bScallToFitOnePage;
                  previewThePages(pp_pf.getOrientation());
              }
            };
            shrinkButton.addActionListener(lst);
            shrinkButton.setAlignmentY(0.5f);
            shrinkButton.setMargin(new Insets(4,6,4,6));
            tb.add(shrinkButton);
        }

        bt = new JButton("Close");
        lst = new ActionListener() {
          public void actionPerformed(ActionEvent e) {

            dispose();
          }
        };
        bt.addActionListener(lst);
        bt.setAlignmentY(0.5f);
        bt.setMargin(new Insets(4,6,4,6));
        tb.add(bt);
    }

    public int getDisplayScale() {
        String str = m_cbScale.getSelectedItem().toString();
        if (str.endsWith("%")) str = str.substring(0, str.length()-1);
        str = str.trim();
        int scale = 0;
        try { scale = Integer.parseInt(str); }
            catch (NumberFormatException ex) { return 25; }
        return scale ;
    }

  public PrintPreview(Printable target) {
    this(target, "Print Preview", false);
  }

  public PrintPreview(Printable target, String title) {
    this(target, title, false);
  }
  public PrintPreview(Printable target, String title, boolean shrink) {
    super(title);
    setIconImage( new ImageIcon( "teloptica.gif" ).getImage() );
    bScallToFitOnePage = false;  // reset to default
    PrinterJob prnJob = PrinterJob.getPrinterJob();
    pp_pf = prnJob.defaultPage();
    if (pp_pf.getHeight()==0 || pp_pf.getWidth()==0) {
        System.err.println("Unable to determine default page size");
        return;
    }
    setSize(600, 400);
    m_target = target;

    displayArea = null;
    m_preview = null;

    JToolBar tb = new JToolBar();
    createButtons(tb, shrink);

    String[] scales = { "10 %", "25 %", "50 %", "100 %" };
    m_cbScale = new JComboBox(scales);
    m_cbScale.setSelectedIndex(1);
    ActionListener lst = new ActionListener() {
      public void actionPerformed(ActionEvent e) {
        Thread runner = new Thread(PrintPreview.this);
        runner.start();
      }
    };
    m_cbScale.addActionListener(lst);
    m_cbScale.setMaximumSize(m_cbScale.getPreferredSize());
    m_cbScale.setEditable(true);
    tb.addSeparator();
    tb.add(m_cbScale);
    getContentPane().add(tb, BorderLayout.NORTH);

//    previewThePages(PageFormat.PORTRAIT);
    previewThePages(pp_pf.getOrientation());
    setDefaultCloseOperation(DISPOSE_ON_CLOSE);
    setVisible(true);
  }

  public void run() {
      int scale = getDisplayScale();
      width = (int)(m_wPage*scale/100);
      height = (int)(m_hPage*scale/100);

      Component[] comps = m_preview.getComponents();
      for (int k=0; k<comps.length; k++) {
          if (!(comps[k] instanceof PagePreview))
              continue;
          PagePreview pp = (PagePreview)comps[k];
          pp.setScaledSize(width, height);
      }
      m_preview.doLayout();
      m_preview.getParent().getParent().validate();
  }

  class PreviewContainer extends JPanel
  {
    protected int H_GAP = 16;
    protected int V_GAP = 10;

    public Dimension getPreferredSize() {
      int n = getComponentCount();
      if (n == 0)
        return new Dimension(H_GAP, V_GAP);
      Component comp = getComponent(0);
      Dimension dc = comp.getPreferredSize();
      int w = dc.width;
      int h = dc.height;

      Dimension dp = getParent().getSize();
      int nCol = Math.max((dp.width-H_GAP)/(w+H_GAP), 1);
      int nRow = n/nCol;
      if (nRow*nCol < n)
        nRow++;

      int ww = nCol*(w+H_GAP) + H_GAP;
      int hh = nRow*(h+V_GAP) + V_GAP;
      Insets ins = getInsets();
      return new Dimension(ww+ins.left+ins.right,
        hh+ins.top+ins.bottom);
    }

    public Dimension getMaximumSize() {
      return getPreferredSize();
    }

    public Dimension getMinimumSize() {
      return getPreferredSize();
    }

    public void doLayout() {
      Insets ins = getInsets();
      int x = ins.left + H_GAP;
      int y = ins.top + V_GAP;

      int n = getComponentCount();
      if (n == 0)
        return;
      Component comp = getComponent(0);
      Dimension dc = comp.getPreferredSize();
      int w = dc.width;
      int h = dc.height;

      Dimension dp = getParent().getSize();
      int nCol = Math.max((dp.width-H_GAP)/(w+H_GAP), 1);
      int nRow = n/nCol;
      if (nRow*nCol < n)
        nRow++;

      int index = 0;
      for (int k = 0; k<nRow; k++) {
        for (int m = 0; m<nCol; m++) {
          if (index >= n)
            return;
          comp = getComponent(index++);
          comp.setBounds(x, y, w, h);
          x += w+H_GAP;
        }
        y += h+V_GAP;
        x = ins.left + H_GAP;
      }
    }
  }

  class PagePreview extends JPanel
  {
    protected int m_w;
    protected int m_h;
    protected Image m_source;
    protected Image m_img;

    public PagePreview(int w, int h, Image source) {
      m_w = w;
      m_h = h;
      m_source= source;
      m_img = m_source.getScaledInstance(m_w, m_h, Image.SCALE_SMOOTH);
      m_img.flush();
      setBackground(Color.white);
      setBorder(new MatteBorder(1, 1, 2, 2, Color.black));
    }

    public void setScaledSize(int w, int h) {
      m_w = w;
      m_h = h;
      m_img = m_source.getScaledInstance(m_w, m_h, Image.SCALE_SMOOTH);
      repaint();
    }

    public Dimension getPreferredSize() {
      Insets ins = getInsets();
      return new Dimension(m_w+ins.left+ins.right,  m_h+ins.top+ins.bottom);
    }

    public Dimension getMaximumSize() {
      return getPreferredSize();
    }

    public Dimension getMinimumSize() {
      return getPreferredSize();
    }

    public void paint(Graphics g) {
      g.setColor(getBackground());
      g.fillRect(0, 0, getWidth(), getHeight());
      g.drawImage(m_img, 0, 0, this);
      paintBorder(g);
    }
  }
}