protected final SingleDisplayModel _model;

protected final MainFrame _mainFrame;

protected final Pageable _print;

protected volatile int _pageNumber;

//zooming modification

Dimension _screenSize = Toolkit.getDefaultToolkit().getScreenSize();

JSlider _zoomSlider = new JSlider(JSlider.HORIZONTAL, 100, 300, 100);

//zooming modification

private JScrollPane _previewScroll;

private final PageChangerUpdater _pageChanger;

private static abstract class PageChangerUpdater {

abstract void update(int pageNumber) throws Exception;

abstract JComponent getComponent();

}

private class JTextFieldChanger extends PageChangerUpdater {

private final JTextField textfield;

private JTextFieldChanger(JTextField tf) { textfield = tf; }

void update(int pageNumber) throws Exception { textfield.setText(String.valueOf(pageNumber)); }

JComponent getComponent() { return textfield; }

}

private class JSpinnerChanger extends PageChangerUpdater {

private volatile JComponent spinner;

private volatile Method setValueMethod;

private final Object[] args = new Object[1];

private JSpinnerChanger(Class<?> spinnerClass, JComponent spinnerObj) throws Exception {

spinner = spinnerObj;

setValueMethod = spinnerClass.getMethod("setValue", Object.class);

}

void update(int pageNumber) throws Exception {

args[0] = Integer.valueOf(pageNumber);

setValueMethod.invoke(spinner, args);

}

JComponent getComponent() { return spinner; }

}

// Print Preview Dimensions

private final int PREVIEW_WIDTH;

private final int PREVIEW_HEIGHT;

private final int PREVIEW_PAGE_WIDTH;

private final int PREVIEW_PAGE_HEIGHT;

private static final double PAGE_ZOOM = 0.7;

private static final int PAGE_BORDER = 20;

private static final int TOOLBAR_HEIGHT = 65;

private static final String ICON_PATH = "/edu/rice/cs/drjava/ui/icons/";

// Components

private JToolBar _toolBar;

private PagePreview _pagePreview;

// Actions

/** Prints the current document. */

private final ActionListener _printListener = new ActionListener() {

public void actionPerformed(ActionEvent ae) {

_print();

_close();

}

};

/** Prints the current document. */

private final Action _closeAction = new AbstractAction("Close") {

public void actionPerformed(ActionEvent ae) { _close(); }

};

/** Displays the next page of the document. */

private final Action _nextPageAction = new AbstractAction("Next Page") {

public void actionPerformed(ActionEvent ae) { _nextPage(); }

};

/** Displays the previous page of the document. */

private final Action _prevPageAction = new AbstractAction("Previous Page") {

public void actionPerformed(ActionEvent ae) { _previousPage(); }

};

/** How Preview Pane responds to window events. */

private final WindowListener _windowCloseListener = new WindowAdapter() {

public void windowClosing(WindowEvent ev) { _close(); }

};

/** Contructs a new PreviewFrame using a parent model and a Pageable object print to show. Should only be called in

public PreviewFrame(SingleDisplayModel model, MainFrame mainFrame, boolean interactions)

throws IllegalStateException {

super("Print Preview");

mainFrame.hourglassOn();

_model = model;

_mainFrame = mainFrame;

_toolBar = new JToolBar();

_print = setUpDocument(model, interactions);

_pageChanger = createPageChanger();

/* Initialize constants. */

//zooming modification

PageFormat first = _print.getPageFormat(0);

PREVIEW_PAGE_WIDTH = (int) (PAGE_ZOOM * first.getWidth());

PREVIEW_PAGE_HEIGHT = (int) (PAGE_ZOOM * first.getHeight());

PREVIEW_WIDTH = PREVIEW_PAGE_WIDTH + (2 * PAGE_BORDER);

PREVIEW_HEIGHT = PREVIEW_PAGE_HEIGHT + (2 * PAGE_BORDER) + TOOLBAR_HEIGHT;

_setUpActions();

_setUpToolBar();

_pagePreview = new PagePreview(PREVIEW_PAGE_WIDTH, PREVIEW_PAGE_HEIGHT);

_pageNumber = 0;

//zooming modification

//PagePreviewContainer ppc = new PagePreviewContainer();

//ppc.add(_pagePreview);

JPanel previewHolder = new JPanel(new BorderLayout());

JPanel tbCont = new JPanel(new BorderLayout());

JPanel cp = new JPanel(new BorderLayout());

//zooming modification

_previewScroll = new JScrollPane(previewHolder);

//_previewScroll = new JScrollPane(cp);

_previewScroll.setHorizontalScrollBarPolicy(JScrollPane.HORIZONTAL_SCROLLBAR_AS_NEEDED);

_previewScroll.setVerticalScrollBarPolicy(JScrollPane.VERTICAL_SCROLLBAR_AS_NEEDED);

tbCont.add(_toolBar,BorderLayout.NORTH);

tbCont.add(Box.createVerticalStrut(10),BorderLayout.SOUTH);

tbCont.setBorder(new EmptyBorder(0,0,5,0));

//zooming modification

previewHolder.add(_pagePreview, BorderLayout.CENTER);

cp.add(_previewScroll);

setContentPane(cp);

//setContentPane(_previewScroll);

//cp.add(_pagePreview, BorderLayout.CENTER);

cp.setBorder(new EmptyBorder(5,5,5,5));

cp.add(tbCont, BorderLayout.NORTH);

//zooming modification

//cp.add(ppc, BorderLayout.SOUTH);

addWindowListener(_windowCloseListener);

showPage();

_updateActions();

//zooming modification

//setSize(screenSize.width, screenSize.height);

setSize(PREVIEW_WIDTH, PREVIEW_HEIGHT);

setDefaultCloseOperation(DISPOSE_ON_CLOSE);

initDone(); // call mandated by SwingFrame contract

setVisible(true);

}

//zooming modification

public void setZoom(int percent, boolean fast){

int h = (int)((PREVIEW_PAGE_HEIGHT * percent) / 100.0);

int w = (int)((PREVIEW_PAGE_WIDTH * percent) / 100.0);

_pagePreview.updateScaled(w, h, fast);

repaint();

if (!fast) {

refreshScreen();

}

}

public void refreshScreen() {

int previewWidth = _pagePreview.getPreferredSize().width + (2 * PAGE_BORDER);

int previewHeight = _pagePreview.getPreferredSize().height + (2 * PAGE_BORDER) + TOOLBAR_HEIGHT;

if (previewWidth > _screenSize.width - TOOLBAR_HEIGHT) previewWidth = _screenSize.width - TOOLBAR_HEIGHT;

if (previewHeight > _screenSize.height - TOOLBAR_HEIGHT) previewHeight = _screenSize.height - TOOLBAR_HEIGHT;

setSize(previewWidth, previewHeight);

}

/** Prints the document being previewed */

abstract protected void _print();

/** Sets up the document to be displayed and returns the Pageable object that allows display by pages

abstract protected Pageable setUpDocument(SingleDisplayModel model, boolean interactions);

private void _close() {

dispose();

_mainFrame.hourglassOff();

}

private void _nextPage() {

_pageNumber++;

_goToPage(_pageNumber);

}

private void _previousPage() {

_pageNumber--;

_goToPage(_pageNumber);

}

private void _goToPage(int pi) {

_pageNumber = pi;

showPage();

_updateActions();

}

protected void _showError(Exception e, String title, String message) {

JOptionPane.showMessageDialog(this, message + "\n" + e, title, JOptionPane.ERROR_MESSAGE);

}

/** Updates all of the buttons on the page to reflect the current state of the PreviewWindows. Enables/Disables the

private void _updateActions() {

_nextPageAction.setEnabled(_print.getNumberOfPages() > (_pageNumber + 1));

_prevPageAction.setEnabled(_pageNumber > 0);

try { _pageChanger.update(_pageNumber + 1); }

catch(Exception e) { /* ignore */ }

}

/** Initializes all action objects. Adds icons and descriptions to several of the actions. */

private void _setUpActions() {

//_printAction.putValue(Action.SHORT_DESCRIPTION, "Print");

_closeAction.putValue(Action.SHORT_DESCRIPTION, "Close");

//zooming modification

//_zoomInAction.putValue(Action.SHORT_DESCRIPTION, "Zoom In");

//_zoomOutAction.putValue(Action.SHORT_DESCRIPTION, "Zoom Out");

//_zoomOutAction.setEnabled(false);

// _printAction.putValue(Action.SMALL_ICON, _getIcon("Print16.gif"));

_nextPageAction.putValue(Action.SMALL_ICON, _getIcon("Forward16.gif"));

_nextPageAction.putValue(Action.SHORT_DESCRIPTION, "Next Page");

_prevPageAction.putValue(Action.SMALL_ICON, _getIcon("Back16.gif"));

_prevPageAction.putValue(Action.SHORT_DESCRIPTION, "Previous Page");

}

private PageChangerUpdater createPageChanger() {

//_pageTextField.setAction(_goToPageAction);

// _goToPageAction.putValue(Action.SHORT_DESCRIPTION, "Goto Page");

try {

Class<?> spinnerClass = Class.forName("javax.swing.JSpinner");

final JComponent spinner = (JComponent) spinnerClass.newInstance();

final Method getter = spinnerClass.getMethod("getValue",new Class<?>[0]);

Object model = callMethod(spinner, spinnerClass, "getModel",null,null);

Class<?> modelClass = model.getClass();

Class<?>[] ca = new Class<?>[] {Comparable.class};

Object[] aa = new Object[] {Integer.valueOf(1)};

callMethod(model,modelClass,"setMinimum",ca,aa);

aa[0] = Integer.valueOf(_print.getNumberOfPages());

callMethod(model,modelClass,"setMaximum",ca,aa);

ca[0] = ChangeListener.class;

aa[0] = new ChangeListener() {

public void stateChanged(ChangeEvent ev) {

int num = _pageNumber;

try {

num = ((Number) getter.invoke(spinner,new Object[0])).intValue()-1;

if ((num >= 0) && (num < _print.getNumberOfPages())) _goToPage(num);

else _updateActions();

}

catch(IllegalAccessException ex) { _updateActions(); }

catch(InvocationTargetException ex) { _updateActions(); }

}

};

callMethod(spinner, spinnerClass,"addChangeListener",ca,aa);

return new JSpinnerChanger(spinnerClass, spinner);

} catch(Exception e) {

/** Displays the previous page of the document. */

final JTextField tf = new JTextField();

tf.addActionListener(new ActionListener() {

public void actionPerformed(ActionEvent ae) {

try {

int pageToGoTo = Integer.parseInt(tf.getText()) - 1;

if ((pageToGoTo < 0) || (pageToGoTo >= _print.getNumberOfPages())) { _updateActions(); }

else _goToPage(pageToGoTo);

}

catch (NumberFormatException e) { _updateActions(); }

}

});

return new JTextFieldChanger(tf);

}

}

private static Object callMethod(Object rec, Class<?> c, String name, Class<?>[] ca, Object[] args) throws Exception {

Method m = c.getMethod(name,ca);

return m.invoke(rec,args);

}

/** Mirrored from MainFrame, will later use the same Icon access code. */

private ImageIcon _getIcon(String name) {

URL url = PreviewFrame.class.getResource(ICON_PATH + name);

if (url != null) return new ImageIcon(url);

return null;

}

/** Sets up the toolbar with all of the necessary buttons. */

private void _setUpToolBar() {

_toolBar.setFloatable(false);

// Print and Close buttons

JButton printButton = new JButton("Print...",_getIcon("Print16.gif"));

printButton.setToolTipText("Print this document");

printButton.addActionListener(_printListener);

_toolBar.add(printButton);

_toolBar.addSeparator();

_toolBar.add(_closeAction);

// Horizontal Gap

_toolBar.add(Box.createHorizontalGlue());

//zooming modification

//_toolBar.add(_zoomOutAction);

//_toolBar.add(_zoomInAction);

//zoomSlider.setMajorTickSpacing(10);

//zoomSlider.setSnapToTicks(true);

_zoomSlider.setPaintLabels(true);

_zoomSlider.setLabelTable(_zoomSlider.createStandardLabels(100));

_zoomSlider.addChangeListener(new ChangeListener() {

public void stateChanged(ChangeEvent evt) {

JSlider slider = (JSlider) evt.getSource();

setZoom(slider.getValue(), slider.getValueIsAdjusting());

}

});

_toolBar.add(_zoomSlider);

// Navigation components

_toolBar.add(_prevPageAction);

_toolBar.add(_nextPageAction);

_toolBar.addSeparator();

JLabel gotop = new JLabel("Page");

JLabel of = new JLabel(" of " + _print.getNumberOfPages());

_toolBar.add(gotop);

_toolBar.addSeparator();

JComponent c = _pageChanger.getComponent();

Dimension d = c.getPreferredSize();

d = new Dimension(100,d.height);

c.setMaximumSize(d);

c.setPreferredSize(d);

c.setMinimumSize(d);

c.setToolTipText("Goto Page");

_toolBar.add(c);

_toolBar.add(of);

}

/** Generates an Image, prints to it, and then displays the image on the page. */

private void showPage() {

BufferedImage img = new BufferedImage((int) _model.getPageFormat().getWidth(),

(int) _model.getPageFormat().getHeight(),

BufferedImage.TYPE_INT_RGB);

Graphics g = img.getGraphics();

g.setColor(Color.white);

g.fillRect(0, 0, (int) _model.getPageFormat().getWidth(), (int) _model.getPageFormat().getHeight());

try {

_print.getPrintable(_pageNumber).print(g, _model.getPageFormat(), _pageNumber);

_pagePreview.setImage(img);

}

catch (PrinterException e) { /* ignore */ }

}

/** Internal class which holds (and places) the PagePreview object. */

class PagePreviewContainer extends JPanel {

public Dimension getPreferredSize() { return getParent().getSize(); }

/** Places the PagePreview component into the center of this object */

public void doLayout() {

Component cp = getComponent(0);

Dimension dm = cp.getPreferredSize();

int Hindent = (int) (getPreferredSize().getWidth() - dm.getWidth()) / 2;

int Vindent = TOOLBAR_HEIGHT + (int) ((getPreferredSize().getHeight() - dm.getHeight() - TOOLBAR_HEIGHT) / 2);

_pagePreview.setBounds(Hindent, Vindent, (int) dm.getWidth(), (int) dm.getHeight());

}

}

/** Static inner class which displays the image on the screen, and holds the Image object. */

static class PagePreview extends JPanel {

//zooming modification

//we need to change the variables from final to non-final because we need to enlarge the page preview area when we zoom in

protected int _width;

protected int _height;

protected volatile Image _source;

protected volatile Image _image;

/** Constructs a PagePreview object with given width and height. */

public PagePreview(int width, int height) {

super();

_width = width;

_height = height;

setBorder(new MatteBorder(1, 1, 2, 2, Color.black));

setBackground(Color.white);

}

/** Scales the interal image to the appropriate size. */

protected void updateScaled() {

_image = _source.getScaledInstance(_width, _height, Image.SCALE_SMOOTH);

_image.flush();

}

//zooming modification

protected void updateScaled(int newWidth, int newHeight, boolean fast) {

_width = newWidth;

_height = newHeight;

_image = _source.getScaledInstance(newWidth, newHeight, fast?Image.SCALE_FAST:Image.SCALE_SMOOTH);

_image.flush();

}

/** Updates the image of this PagePreview.

public void setImage(Image i) {

_source = i;

updateScaled();

repaint();

}

//zooming modification

public int getHeight() {

return _height;

}

public int getWidth() {

return _width;

}

public Dimension getPreferredSize() { return new Dimension(_width, _height); }

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

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

public void paint(Graphics g) {

g.setColor(getBackground());

g.fillRect(0, 0, _width, _height);

g.drawImage(_image, 0, 0, this);

paintBorder(g);

}

}