content: package org.eclipse.wst.jsdt.internal.ui.text.html;
  // COPIED FROM org.eclipse.jface.internal.text.html
  // to get around "discouraged access" errors
  /*******************************************************************************
   * Copyright (c) 2000, 2008 IBM Corporation and others.
   * All rights reserved. This program and the accompanying materials
   * are made available under the terms of the Eclipse Public License v1.0
   * which accompanies this distribution, and is available at
   * http://www.eclipse.org/legal/epl-v10.html
   *
   * Contributors:
   *     IBM Corporation - initial API and implementation
   *******************************************************************************/
  
  import java.io.IOException;
  import java.io.StringReader;
  import java.util.Iterator;
  
  import org.eclipse.swt.SWT;
  import org.eclipse.swt.SWTError;
  import org.eclipse.swt.browser.Browser;
  import org.eclipse.swt.browser.LocationAdapter;
  import org.eclipse.swt.browser.LocationEvent;
  import org.eclipse.swt.custom.StyleRange;
  import org.eclipse.swt.events.DisposeEvent;
  import org.eclipse.swt.events.DisposeListener;
  import org.eclipse.swt.events.FocusEvent;
  import org.eclipse.swt.events.FocusListener;
  import org.eclipse.swt.events.KeyEvent;
  import org.eclipse.swt.events.KeyListener;
  import org.eclipse.swt.graphics.Color;
  import org.eclipse.swt.graphics.Font;
  import org.eclipse.swt.graphics.FontData;
  import org.eclipse.swt.graphics.Point;
  import org.eclipse.swt.graphics.Rectangle;
  import org.eclipse.swt.graphics.TextLayout;
  import org.eclipse.swt.graphics.TextStyle;
  import org.eclipse.swt.layout.GridData;
  import org.eclipse.swt.layout.GridLayout;
  import org.eclipse.swt.widgets.Composite;
  import org.eclipse.swt.widgets.Display;
  import org.eclipse.swt.widgets.Event;
  import org.eclipse.swt.widgets.Label;
  import org.eclipse.swt.widgets.Listener;
  import org.eclipse.swt.widgets.Menu;
  import org.eclipse.swt.widgets.Shell;
  
  import org.eclipse.core.runtime.ListenerList;
  
  import org.eclipse.jface.text.IInformationControl;
  import org.eclipse.jface.text.IInformationControlExtension;
  import org.eclipse.jface.text.IInformationControlExtension3;
  import org.eclipse.jface.text.IInformationControlExtension4;
  import org.eclipse.jface.text.TextPresentation;
  
  
  /**
   * Displays textual information in a {@link org.eclipse.swt.browser.Browser} widget.
   * <p>
   * Moved into this package from <code>org.eclipse.jface.internal.text.revisions</code>.</p>
   * <p>
   * This class may be instantiated; it is not intended to be subclassed.</p>
   * <p>
   * Current problems:
   * <ul>
   * 	<li>the size computation is too small</li>
   * 	<li>focusLost event is not sent - see https://bugs.eclipse.org/bugs/show_bug.cgi?id=84532</li>
   * </ul>
   * </p>
   * 
   * 
   */
  public class BrowserInformationControl implements IInformationControl, IInformationControlExtension, IInformationControlExtension3, IInformationControlExtension4, DisposeListener {
  
  
  	/**
  	 * Tells whether the SWT Browser widget and hence this information
  	 * control is available.
  	 *
  	 * @param parent the parent component used for checking or <code>null</code> if none
  	 * @return <code>true</code> if this control is available
  	 */
  	public static boolean isAvailable(Composite parent) {
  		if (!fgAvailabilityChecked) {
  			try {
  				Browser browser= new Browser(parent, SWT.NONE);
  				browser.dispose();
  				fgIsAvailable= true;
  			} catch (SWTError er) {
  				fgIsAvailable= false;
  			} finally {
  				fgAvailabilityChecked= true;
  			}
  		}
  
  		return fgIsAvailable;
  	}
  
  
  	/** Border thickness in pixels. */
  	private static final int BORDER= 1;
  	
  	/**
  	 * Minimal size constraints.
  	 * 
  	 */
  	private static final int MIN_WIDTH= 80;
  	private static final int MIN_HEIGHT= 80;
  
  	
  	/**
  	 * Availability checking cache.
  	 */
  	private static boolean fgIsAvailable= false;
  	private static boolean fgAvailabilityChecked= false;
  
  	/** The control's shell */
  	private Shell fShell;
  	/** The control's browser widget */
  	private Browser fBrowser;
  	/** Tells whether the browser has content */
  	private boolean fBrowserHasContent;
  	/** The control width constraint */
  	private int fMaxWidth= SWT.DEFAULT;
  	/** The control height constraint */
  	private int fMaxHeight= SWT.DEFAULT;
  	private Font fStatusTextFont;
  	private Label fStatusTextField;
  	private String fStatusFieldText;
  	private boolean fHideScrollBars;
  	private Listener fDeactivateListener;
  	private ListenerList fFocusListeners= new ListenerList();
  	private Label fSeparator;
  	private String fInputText;
  	private TextLayout fTextLayout;
  
  	private TextStyle fBoldStyle;
  
  	/**
  	 * Creates a default information control with the given shell as parent. The given
  	 * information presenter is used to process the information to be displayed. The given
  	 * styles are applied to the created styled text widget.
  	 *
  	 * @param parent the parent shell
  	 * @param shellStyle the additional styles for the shell
  	 * @param style the additional styles for the styled text widget
  	 */
  	public BrowserInformationControl(Shell parent, int shellStyle, int style) {
  		this(parent, shellStyle, style, null);
  	}
  
  	/**
  	 * Creates a default information control with the given shell as parent. The given
  	 * information presenter is used to process the information to be displayed. The given
  	 * styles are applied to the created styled text widget.
  	 *
  	 * @param parent the parent shell
  	 * @param shellStyle the additional styles for the shell
  	 * @param style the additional styles for the styled text widget
  	 * @param statusFieldText the text to be used in the optional status field
  	 *                         or <code>null</code> if the status field should be hidden
  	 */
  	public BrowserInformationControl(Shell parent, int shellStyle, int style, String statusFieldText) {
  		fStatusFieldText= statusFieldText;
  		
  		fShell= new Shell(parent, SWT.NO_FOCUS | SWT.ON_TOP | shellStyle);
  		Display display= fShell.getDisplay();
  		fShell.setBackground(display.getSystemColor(SWT.COLOR_BLACK));
  		fTextLayout= new TextLayout(display);
  
  		Composite composite= fShell;
  		GridLayout layout= new GridLayout(1, false);
  		int border= ((shellStyle & SWT.NO_TRIM) == 0) ? 0 : BORDER;
  		layout.marginHeight= border;
  		layout.marginWidth= border;
  		composite.setLayout(layout);
  		
  		if (statusFieldText != null) {
  			composite= new Composite(composite, SWT.NONE);
  			layout= new GridLayout(1, false);
  			layout.marginHeight= 0;
  			layout.marginWidth= 0;
  			layout.verticalSpacing= 1;
  			layout.horizontalSpacing= 1;
  			composite.setLayout(layout);
  			
  			GridData  gd= new GridData(GridData.FILL_BOTH);
  			composite.setLayoutData(gd);
  			
  			composite.setForeground(display.getSystemColor(SWT.COLOR_INFO_FOREGROUND));
  			composite.setBackground(display.getSystemColor(SWT.COLOR_INFO_BACKGROUND));
  		}
  
  		// Browser field
  		fBrowser= new Browser(composite, SWT.NONE);
  		fHideScrollBars= (style & SWT.V_SCROLL) == 0 && (style & SWT.H_SCROLL) == 0;
  		
  		GridData gd= new GridData(GridData.BEGINNING | GridData.FILL_BOTH);
  		fBrowser.setLayoutData(gd);
  		
  		fBrowser.setForeground(display.getSystemColor(SWT.COLOR_INFO_FOREGROUND));
  		fBrowser.setBackground(display.getSystemColor(SWT.COLOR_INFO_BACKGROUND));
  		fBrowser.addKeyListener(new KeyListener() {
  
  			public void keyPressed(KeyEvent e)  {
  				if (e.character == 0x1B) // ESC
  					fShell.dispose();
  			}
  
  			public void keyReleased(KeyEvent e) {}
  		});
  		/*
  		 * XXX revisit when the Browser support is better 
  		 * See https://bugs.eclipse.org/bugs/show_bug.cgi?id=107629. Choosing a link to a
  		 * non-available target will show an error dialog behind the ON_TOP shell that seemingly
  		 * blocks the workbench. Disable links completely for now.
  		 */
  		fBrowser.addLocationListener(new LocationAdapter() {
  			/*
  			 * @see org.eclipse.swt.browser.LocationAdapter#changing(org.eclipse.swt.browser.LocationEvent)
  			 */
  			public void changing(LocationEvent event) {
  				String location= event.location;
  				/*
  				 * Using the Browser.setText API triggers a location change to "about:blank" with
  				 * the mozilla widget. The Browser on carbon uses yet another kind of special
  				 * initialization URLs. 
  				 * TODO remove this code once https://bugs.eclipse.org/bugs/show_bug.cgi?id=130314 is fixed
  				 */
  				if (!"about:blank".equals(location) && !("carbon".equals(SWT.getPlatform()) && location.startsWith("applewebdata:"))) //$NON-NLS-1$ //$NON-NLS-2$ //$NON-NLS-3$
  					event.doit= false;
  			}
  		});
  
  		// Replace browser's built-in context menu with none
  		fBrowser.setMenu(new Menu(fShell, SWT.NONE));
  
  		// Status field
  		if (statusFieldText != null) {
  
  			fSeparator= new Label(composite, SWT.SEPARATOR | SWT.HORIZONTAL | SWT.LINE_DOT);
  			fSeparator.setLayoutData(new GridData(GridData.FILL_HORIZONTAL));
  
  			// Status field label
  			fStatusTextField= new Label(composite, SWT.RIGHT);
  			fStatusTextField.setText(statusFieldText);
  			Font font= fStatusTextField.getFont();
  			FontData[] fontDatas= font.getFontData();
  			for (int i= 0; i < fontDatas.length; i++)
  				fontDatas[i].setHeight(fontDatas[i].getHeight() * 9 / 10);
  			fStatusTextFont= new Font(fStatusTextField.getDisplay(), fontDatas);
  			fStatusTextField.setFont(fStatusTextFont);
  			gd= new GridData(GridData.FILL_HORIZONTAL | GridData.HORIZONTAL_ALIGN_BEGINNING | GridData.VERTICAL_ALIGN_BEGINNING);
  			fStatusTextField.setLayoutData(gd);
  
  			fStatusTextField.setForeground(display.getSystemColor(SWT.COLOR_WIDGET_DARK_SHADOW));
  
  			fStatusTextField.setBackground(display.getSystemColor(SWT.COLOR_INFO_BACKGROUND));
  		}
  
  		addDisposeListener(this);		
  		createTextLayout();
  	}
  
  	/**
  	 * Creates a default information control with the given shell as parent. The given
  	 * information presenter is used to process the information to be displayed. The given
  	 * styles are applied to the created styled text widget.
  	 *
  	 * @param parent the parent shell
  	 * @param style the additional styles for the browser widget
  	 */
  	public BrowserInformationControl(Shell parent,int style) {
  		this(parent, SWT.TOOL | SWT.NO_TRIM, style);
  	}
  
  	/**
  	 * Creates a default information control with the given shell as parent.
  	 * No information presenter is used to process the information
  	 * to be displayed. No additional styles are applied to the styled text widget.
  	 *
  	 * @param parent the parent shell
  	 */
  	public BrowserInformationControl(Shell parent) {
  		this(parent, SWT.NONE);
  	}
  
  
  	/*
  	 * @see IInformationControl#setInformation(String)
  	 */
  	public void setInformation(String content) {
  		fBrowserHasContent= content != null && content.length() > 0;
  
  		if (!fBrowserHasContent)
  			content= "<html><body ></html>"; //$NON-NLS-1$
  		
  		fInputText= content;
  
  		int shellStyle= fShell.getStyle();
  		boolean RTL= (shellStyle & SWT.RIGHT_TO_LEFT) != 0;
  
  		String[] styles= null;
  		if (RTL && !fHideScrollBars)
  			styles= new String[] { "direction:rtl;", "word-wrap:break-word;" }; //$NON-NLS-1$ //$NON-NLS-2$
  		else if (RTL && fHideScrollBars)
  			styles= new String[] { "direction:rtl;", "overflow:hidden;", "word-wrap:break-word;" }; //$NON-NLS-1$ //$NON-NLS-2$ //$NON-NLS-3$
  		else if (fHideScrollBars && true)
  			styles= new String[] { "overflow:hidden;", "word-wrap: break-word;" }; //$NON-NLS-1$ //$NON-NLS-2$
  		
  		if (styles != null) {
  			StringBuffer buffer= new StringBuffer(content);
  			HTMLPrinter.insertStyles(buffer, styles);
  			content= buffer.toString();
  		}
  		
  		fBrowser.setText(content);
  	
  	}
  
  	/*
  	 * @see org.eclipse.jdt.internal.ui.text.IInformationControlExtension4#setStatusText(java.lang.String)
  	 * 
  	 */
  	public void setStatusText(String statusFieldText) {
  		fStatusFieldText= statusFieldText;
  	}
  
  	/*
  	 * @see IInformationControl#setVisible(boolean)
  	 */
  	public void setVisible(boolean visible) {
  		if (fShell.isVisible() == visible)
  			return;
  		
  		if (visible) {
  			if (fStatusTextField != null) {
  				boolean state= fStatusFieldText != null;
  				if (state)
  					fStatusTextField.setText(fStatusFieldText);
  				fStatusTextField.setVisible(state);
  				fSeparator.setVisible(state);
  			}
  		}
  
  		fShell.setVisible(visible);
  		if (!visible)
  			setInformation(""); //$NON-NLS-1$
  	}
  
  	/**
  	 * Creates and initializes the text layout used
  	 * to compute the size hint.
  	 * 
  	 * 
  	 */
  	private void createTextLayout() {
  		fTextLayout= new TextLayout(fBrowser.getDisplay());
  		
  		// Initialize fonts
  		Font font= fBrowser.getFont();
  		fTextLayout.setFont(font);
  		fTextLayout.setWidth(-1);
  		FontData[] fontData= font.getFontData();
  		for (int i= 0; i < fontData.length; i++)
  			fontData[i].setStyle(SWT.BOLD);
  		font= new Font(fShell.getDisplay(), fontData);
  		fBoldStyle= new TextStyle(font, null, null);
  		
  		// Compute and set tab width
  		fTextLayout.setText("    "); //$NON-NLS-1$
  		int tabWidth = fTextLayout.getBounds().width;
  		fTextLayout.setTabs(new int[] {tabWidth});
  
  		fTextLayout.setText(""); //$NON-NLS-1$
  	}
  
  	/*
  	 * @see IInformationControl#dispose()
  	 */
  	public void dispose() {
  		fTextLayout.dispose();
  		fTextLayout= null;
  		fBoldStyle.font.dispose();
  		fBoldStyle= null;
  		if (fShell != null && !fShell.isDisposed())
  			fShell.dispose();
  		else
  			widgetDisposed(null);
  	}
  
  	/*
  	 * @see org.eclipse.swt.events.DisposeListener#widgetDisposed(org.eclipse.swt.events.DisposeEvent)
  	 */
  	public void widgetDisposed(DisposeEvent event) {
  		if (fStatusTextFont != null && !fStatusTextFont.isDisposed())
  			fStatusTextFont.dispose();
  
  		fShell= null;
  		fBrowser= null;
  		fStatusTextFont= null;
  	}
  
  	/*
  	 * @see IInformationControl#setSize(int, int)
  	 */
  	public void setSize(int width, int height) {
  		fShell.setSize(Math.min(width, fMaxWidth), Math.min(height, fMaxHeight));
  	}
  
  	/*
  	 * @see IInformationControl#setLocation(Point)
  	 */
  	public void setLocation(Point location) {
  		fShell.setLocation(location);
  	}
  
  	/*
  	 * @see IInformationControl#setSizeConstraints(int, int)
  	 */
  	public void setSizeConstraints(int maxWidth, int maxHeight) {
  		fMaxWidth= maxWidth;
  		fMaxHeight= maxHeight;
  	}
  
  	/*
  	 * @see IInformationControl#computeSizeHint()
  	 */
  	public Point computeSizeHint() {
  		TextPresentation presentation= new TextPresentation();
  		HTML2TextReader reader= new HTML2TextReader(new StringReader(fInputText), presentation);
  		String text;
  		try {
  			text= reader.getString();
  		} catch (IOException e) {
  			text= ""; //$NON-NLS-1$
  		}
  
  		fTextLayout.setText(text);
  		Iterator iter= presentation.getAllStyleRangeIterator();
  		while (iter.hasNext()) {
  			StyleRange sr= (StyleRange)iter.next();
  			if (sr.fontStyle == SWT.BOLD)
  				fTextLayout.setStyle(fBoldStyle, sr.start, sr.start + sr.length - 1);
  		}
  		Rectangle bounds= fTextLayout.getBounds();
  		int width= bounds.width;
  		int height= bounds.height;
  		
  		width += 15; 
  		height += 25; 
  
  		if (fStatusFieldText != null && fSeparator != null) {
  			fTextLayout.setText(fStatusFieldText);
  			Rectangle statusBounds= fTextLayout.getBounds();
  			Rectangle separatorBounds= fSeparator.getBounds();
  			width= Math.max(width, statusBounds.width);
  			height= height + statusBounds.height + separatorBounds.height;
  		}
  
  		// Apply size constraints
  		if (fMaxWidth != SWT.DEFAULT)
  			width= Math.min(fMaxWidth, width);
  		if (fMaxHeight != SWT.DEFAULT)
  			height= Math.min(fMaxHeight, height);
  
  		// Ensure minimal size
  		width= Math.max(MIN_WIDTH, width);
  		height= Math.max(MIN_HEIGHT, height);
  		
  		return new Point(width, height);
  	}
  
  	/*
  	 * @see org.eclipse.jface.text.IInformationControlExtension3#computeTrim()
  	 */
  	public Rectangle computeTrim() {
  		return fShell.computeTrim(0, 0, 0, 0);
  	}
  
  	/*
  	 * @see org.eclipse.jface.text.IInformationControlExtension3#getBounds()
  	 */
  	public Rectangle getBounds() {
  		return fShell.getBounds();
  	}
  
  	/*
  	 * @see org.eclipse.jface.text.IInformationControlExtension3#restoresLocation()
  	 */
  	public boolean restoresLocation() {
  		return false;
  	}
  
  	/*
  	 * @see org.eclipse.jface.text.IInformationControlExtension3#restoresSize()
  	 */
  	public boolean restoresSize() {
  		return false;
  	}
  
  	/*
  	 * @see IInformationControl#addDisposeListener(DisposeListener)
  	 */
  	public void addDisposeListener(DisposeListener listener) {
  		fShell.addDisposeListener(listener);
  	}
  
  	/*
  	 * @see IInformationControl#removeDisposeListener(DisposeListener)
  	 */
  	public void removeDisposeListener(DisposeListener listener) {
  		fShell.removeDisposeListener(listener);
  	}
  
  	/*
  	 * @see IInformationControl#setForegroundColor(Color)
  	 */
  	public void setForegroundColor(Color foreground) {
  		fBrowser.setForeground(foreground);
  	}
  
  	/*
  	 * @see IInformationControl#setBackgroundColor(Color)
  	 */
  	public void setBackgroundColor(Color background) {
  		fBrowser.setBackground(background);
  	}
  
  	/*
  	 * @see IInformationControl#isFocusControl()
  	 */
  	public boolean isFocusControl() {
  		return fBrowser.isFocusControl();
  	}
  
  	/*
  	 * @see IInformationControl#setFocus()
  	 */
  	public void setFocus() {
  		fShell.forceFocus();
  		fBrowser.setFocus();
  	}
  
  	/*
  	 * @see IInformationControl#addFocusListener(FocusListener)
  	 */
  	public void addFocusListener(final FocusListener listener) {
  		fBrowser.addFocusListener(listener);
  
  		/*
  		 * FIXME:	This is a workaround for bug https://bugs.eclipse.org/bugs/show_bug.cgi?id=84532
  		 * 			(Browser widget does not send focusLost event)
  		 */
  		if (fFocusListeners.isEmpty()) {
  			fDeactivateListener=  new Listener() {
  				public void handleEvent(Event event) {
  					Object[] listeners= fFocusListeners.getListeners();
  					for (int i = 0; i < listeners.length; i++)
  						((FocusListener)listeners[i]).focusLost(new FocusEvent(event));
  				}
  			};
  			fBrowser.getShell().addListener(SWT.Deactivate, fDeactivateListener);
  		}
  		fFocusListeners.add(listener);
  	}
  
  	/*
  	 * @see IInformationControl#removeFocusListener(FocusListener)
  	 */
  	public void removeFocusListener(FocusListener listener) {
  		fBrowser.removeFocusListener(listener);
  
  		/*
  		 * FIXME:	This is a workaround for bug https://bugs.eclipse.org/bugs/show_bug.cgi?id=84532
  		 * 			(Browser widget does not send focusLost event)
  		 */
  		fFocusListeners.remove(listener);
  		if (fFocusListeners.isEmpty()) {
  			fBrowser.getShell().removeListener(SWT.Deactivate, fDeactivateListener);
  			fDeactivateListener= null;
  		}
  	}
  
  	/*
  	 * @see IInformationControlExtension#hasContents()
  	 */
  	public boolean hasContents() {
  		return fBrowserHasContent;
  	}
  }
  