org.eclipse.jface.text/src/org/eclipse/jface/text/contentassist/CompletionProposalPopup.java - platform/eclipse.platform.text - Git at Google

 /*******************************************************************************
  * Copyright (c) 2000, 2003 IBM Corporation and others.
  * All rights reserved. This program and the accompanying materials
  * are made available under the terms of the Common Public License v1.0
  * which accompanies this distribution, and is available at
  * http://www.eclipse.org/legal/cpl-v10.html
  *
  * Contributors:
  *     IBM Corporation - initial API and implementation
  *******************************************************************************/

 package org.eclipse.jface.text.contentassist;


 import java.util.ArrayList;
 import java.util.List;

 import org.eclipse.swt.SWT;
 import org.eclipse.swt.custom.BusyIndicator;
 import org.eclipse.swt.custom.StyledText;
 import org.eclipse.swt.events.ControlEvent;
 import org.eclipse.swt.events.ControlListener;
 import org.eclipse.swt.events.KeyEvent;
 import org.eclipse.swt.events.KeyListener;
 import org.eclipse.swt.events.SelectionEvent;
 import org.eclipse.swt.events.SelectionListener;
 import org.eclipse.swt.events.VerifyEvent;
 import org.eclipse.swt.graphics.Color;
 import org.eclipse.swt.graphics.Point;
 import org.eclipse.swt.layout.GridData;
 import org.eclipse.swt.layout.GridLayout;
 import org.eclipse.swt.widgets.Control;
 import org.eclipse.swt.widgets.Shell;
 import org.eclipse.swt.widgets.Table;
 import org.eclipse.swt.widgets.TableItem;

 import org.eclipse.jface.text.BadLocationException;
 import org.eclipse.jface.text.DocumentEvent;
 import org.eclipse.jface.text.IDocument;
 import org.eclipse.jface.text.IDocumentListener;
 import org.eclipse.jface.text.IRewriteTarget;
 import org.eclipse.jface.text.ITextViewer;
 import org.eclipse.jface.text.ITextViewerExtension;
 import org.eclipse.jface.text.TextUtilities;


 /**
  * This class is used to present proposals to the user. If additional
  * information exists for a proposal, then selecting that proposal
  * will result in the information being displayed in a secondary
  * window.
  *
  * @see org.eclipse.jface.text.contentassist.ICompletionProposal
  * @see org.eclipse.jface.text.contentassist.AdditionalInfoController
  */
 class CompletionProposalPopup implements IContentAssistListener {

 	/** The associated text viewer */
 	private ITextViewer fViewer;
 	/** The associated content assistant */
 	private ContentAssistant fContentAssistant;
 	/** The used additional info controller */
 	private AdditionalInfoController fAdditionalInfoController;
 	/** The closing strategy for this completion proposal popup */
 	private PopupCloser fPopupCloser= new PopupCloser();
 	/** The popup shell */
 	private Shell fProposalShell;
 	/** The proposal table */
 	private Table fProposalTable;
 	/** Indicates whether a completion proposal is being inserted */
 	private boolean fInserting= false;
 	/** The key listener to control navigation */
 	private KeyListener fKeyListener;
 	/** List of document events used for filtering proposals */
 	private List fDocumentEvents= new ArrayList();
 	/** Listener filling the document event queue */
 	private IDocumentListener fDocumentListener= new IDocumentListener() {
 		public void documentAboutToBeChanged(DocumentEvent event) {}
 		public void documentChanged(DocumentEvent event) {
 			fDocumentEvents.add(event);
 		}
 	};
 	/** Reentrance count for <code>filterProposals</code> */
 	private long fInvocationCounter= 0;
 	/** The filter list of proposals */
 	private ICompletionProposal[] fFilteredProposals;
 	/** The computed list of proposals */
 	private ICompletionProposal[] fComputedProposals;
 	/** The offset for which the proposals have been computed */
 	private int fInvocationOffset;
 	/** The offset for which the computed proposaks have been filtered */
 	private int fFilterOffset;
 	/** The default line delimiter of the viewer's widget */
 	private String fLineDelimiter;


 	/**
 	 * Creates a new completion proposal popup for the given elements.
 	 *
 	 * @param contentAssistant the content assistant feeding this popup
 	 * @param viewer the viewer on top of which this popup appears
 	 * @param infoController the info control collaborating with this popup
 	 * @since 2.0
 	 */
 	public CompletionProposalPopup(ContentAssistant contentAssistant, ITextViewer viewer, AdditionalInfoController infoController) {
 		fContentAssistant= contentAssistant;
 		fViewer= viewer;
 		fAdditionalInfoController= infoController;
 	}

 	/**
 	 * Computes and presents completion proposals. The flag indicates whether this call has
 	 * be made out of an auto activation context.
 	 *
 	 * @param autoActivated <code>true</code> if auto activation context
 	 * @return an error message or <code>null</code> in case of no error
 	 */
 	public String showProposals(final boolean autoActivated) {

 		IDocument document= fViewer.getDocument();
 		if (document != null)
 			document.addDocumentListener(fDocumentListener);

 		if (fKeyListener == null) {
 			fKeyListener= new KeyListener() {
 				public void keyPressed(KeyEvent e) {
 					if (!Helper.okToUse(fProposalShell))
 						return;

 					if (e.character == 0 && e.keyCode == SWT.MOD1) {
 						// http://dev.eclipse.org/bugs/show_bug.cgi?id=34754
 						int index= fProposalTable.getSelectionIndex();
 						if (index >= 0)
 							selectProposal(index, true);
 					}
 				}

 				public void keyReleased(KeyEvent e) {
 					if (!Helper.okToUse(fProposalShell))
 						return;

 					if (e.character == 0 && e.keyCode == SWT.MOD1) {
 						// http://dev.eclipse.org/bugs/show_bug.cgi?id=34754
 						int index= fProposalTable.getSelectionIndex();
 						if (index >= 0)
 							selectProposal(index, false);
 					}
 				}
 			};
 		}

 		final StyledText styledText= fViewer.getTextWidget();
 		if (styledText != null && !styledText.isDisposed())
 			styledText.addKeyListener(fKeyListener);

 		BusyIndicator.showWhile(styledText.getDisplay(), new Runnable() {
 			public void run() {

 				fInvocationOffset= fViewer.getSelectedRange().x;
 				fComputedProposals= computeProposals(fInvocationOffset);

 				int count= (fComputedProposals == null ? 0 : fComputedProposals.length);
 				if (count == 0) {

 					if (!autoActivated)
 						styledText.getDisplay().beep();

 				} else {

 					if (count == 1 && !autoActivated && fContentAssistant.isAutoInserting())

 						insertProposal(fComputedProposals[0], (char) 0, 0, fInvocationOffset);

 					else {

 						if (fLineDelimiter == null)
 							fLineDelimiter= styledText.getLineDelimiter();

 						createProposalSelector();
 						setProposals(fComputedProposals);
 						displayProposals();
 					}
 				}
 			}
 		});

 		return getErrorMessage();
 	}

 	/**
 	 * Returns the completion proposal available at the given offset of the
 	 * viewer's document. Delegates the work to the content assistant.
 	 *
 	 * @param offset the offset
 	 * @return the completion proposals available at this offset
 	 */
 	private ICompletionProposal[] computeProposals(int offset) {
 		return fContentAssistant.computeCompletionProposals(fViewer, offset);
 	}

 	/**
 	 * Returns the error message.
 	 *
 	 * @return the error message
 	 */
 	private String getErrorMessage() {
 		return fContentAssistant.getErrorMessage();
 	}

 	/**
 	 * Creates the proposal selector.
 	 */
 	private void createProposalSelector() {
 		if (Helper.okToUse(fProposalShell))
 			return;

 		Control control= fViewer.getTextWidget();
 		fProposalShell= new Shell(control.getShell(), SWT.ON_TOP | SWT.RESIZE );
 		fProposalTable= new Table(fProposalShell, SWT.H_SCROLL | SWT.V_SCROLL);

 		fProposalTable.setLocation(0, 0);
 		if (fAdditionalInfoController != null)
 			fAdditionalInfoController.setSizeConstraints(50, 10, true, false);

 		GridLayout layout= new GridLayout();
 		layout.marginWidth= 0;
 		layout.marginHeight= 0;
 		fProposalShell.setLayout(layout);

 		GridData data= new GridData(GridData.FILL_BOTH);
 		data.heightHint= fProposalTable.getItemHeight() * 10;
 		data.widthHint= 300;
 		fProposalTable.setLayoutData(data);

 		fProposalShell.pack();

 		if (fAdditionalInfoController != null) {
 			fProposalShell.addControlListener(new ControlListener() {

 				public void controlMoved(ControlEvent e) {}

 				public void controlResized(ControlEvent e) {
 					// resets the cached resize constraints
 					fAdditionalInfoController.setSizeConstraints(50, 10, true, false);
 				}
 			});
 		}

 		fProposalShell.setBackground(control.getDisplay().getSystemColor(SWT.COLOR_BLACK));

 		Color c= fContentAssistant.getProposalSelectorBackground();
 		if (c == null)
 			c= control.getDisplay().getSystemColor(SWT.COLOR_INFO_BACKGROUND);
 		fProposalTable.setBackground(c);

 		c= fContentAssistant.getProposalSelectorForeground();
 		if (c == null)
 			c= control.getDisplay().getSystemColor(SWT.COLOR_INFO_FOREGROUND);
 		fProposalTable.setForeground(c);

 		fProposalTable.addSelectionListener(new SelectionListener() {

 			public void widgetSelected(SelectionEvent e) {}

 			public void widgetDefaultSelected(SelectionEvent e) {
 				selectProposalWithMask(e.stateMask);
 			}
 		});
 //		if (fKeyListener != null)
 //			fProposalTable.addKeyListener(fKeyListener);

 		fPopupCloser.install(fContentAssistant, fProposalTable);

 		fProposalTable.setHeaderVisible(false);
 		fContentAssistant.addToLayout(this, fProposalShell, ContentAssistant.LayoutManager.LAYOUT_PROPOSAL_SELECTOR, fContentAssistant.getSelectionOffset());
 	}

 	/**
 	 * Returns the proposal selected in the proposal selector.
 	 *
 	 * @return the selected proposal
 	 * @since 2.0
 	 */
 	private ICompletionProposal getSelectedProposal() {
 		int i= fProposalTable.getSelectionIndex();
 		if (i < 0 || i >= fFilteredProposals.length)
 			return null;
 		return fFilteredProposals[i];
 	}

 	/**
 	 * Takes the selected proposal and applies it.
 	 *
 	 * @param stateMask the state mask
 	 * @since 2.1
 	 */
 	private void selectProposalWithMask(int stateMask) {
 		ICompletionProposal p= getSelectedProposal();
 		hide();
 		if (p != null)
 			insertProposal(p, (char) 0, stateMask, fViewer.getSelectedRange().x);
 	}

 	/**
 	 * Applies the given proposal at the given offset. The given character is the
 	 * one that triggered the insertion of this proposal.
 	 *
 	 * @param p the completion proposal
 	 * @param trigger the trigger character
 	 * @param offset the offset
 	 * @since 2.1
 	 */
 	private void insertProposal(ICompletionProposal p, char trigger, int stateMask, int offset) {

 		fInserting= true;
 		IRewriteTarget target= null;

 		try {

 			IDocument document= fViewer.getDocument();

 			if (fViewer instanceof ITextViewerExtension) {
 				ITextViewerExtension extension= (ITextViewerExtension) fViewer;
 				target= extension.getRewriteTarget();
 			}

 			if (target != null)
 				target.beginCompoundChange();

 			if (p instanceof ICompletionProposalExtension2) {
 				ICompletionProposalExtension2 e= (ICompletionProposalExtension2) p;
 				e.apply(fViewer, trigger, stateMask, offset);
 			} else if (p instanceof ICompletionProposalExtension) {
 				ICompletionProposalExtension e= (ICompletionProposalExtension) p;
 				e.apply(document, trigger, offset);
 			} else {
 				p.apply(document);
 			}

 			Point selection= p.getSelection(document);
 			if (selection != null) {
 				fViewer.setSelectedRange(selection.x, selection.y);
 				fViewer.revealRange(selection.x, selection.y);
 			}

 			IContextInformation info= p.getContextInformation();
 			if (info != null) {

 				int position;
 				if (p instanceof ICompletionProposalExtension) {
 					ICompletionProposalExtension e= (ICompletionProposalExtension) p;
 					position= e.getContextInformationPosition();
 				} else {
 					if (selection == null)
 						selection= fViewer.getSelectedRange();
 					position= selection.x + selection.y;
 				}

 				fContentAssistant.showContextInformation(info, position);
 			}

 		} finally {
 			if (target != null)
 				target.endCompoundChange();
 			fInserting= false;
 		}
 	}

 	/**
 	 * Returns whether this popup has the focus.
 	 *
 	 * @return <code>true</code> if the popup has the focus
 	 */
 	public boolean hasFocus() {
 		if (Helper.okToUse(fProposalShell))
 			return (fProposalShell.isFocusControl() || fProposalTable.isFocusControl());

 		return false;
 	}

 	/**
 	 * Hides this popup.
 	 */
 	public void hide() {

 		IDocument document= fViewer.getDocument();
 		if (document != null)
 			document.removeDocumentListener(fDocumentListener);
 		fDocumentEvents.clear();

 		StyledText styledText= fViewer.getTextWidget();
 		if (fKeyListener != null && styledText != null && !styledText.isDisposed())
 			styledText.removeKeyListener(fKeyListener);

 		if (Helper.okToUse(fProposalTable)) {
 			ICompletionProposal proposal= getSelectedProposal();
 			if (proposal instanceof ICompletionProposalExtension2) {
 				ICompletionProposalExtension2 extension= (ICompletionProposalExtension2) proposal;
 				extension.unselected(fViewer);
 			}
 //			if (fKeyListener != null)
 //				fProposalTable.removeKeyListener(fKeyListener);
 		}

 		if (Helper.okToUse(fProposalShell)) {

 			fContentAssistant.removeContentAssistListener(this, ContentAssistant.PROPOSAL_SELECTOR);

 			fPopupCloser.uninstall();
 			fProposalShell.setVisible(false);
 			fProposalShell.dispose();
 			fProposalShell= null;
 		}

 		fFilteredProposals= null;

 		fContentAssistant.possibleCompletionsClosed();
 	}

 	/**
 	 *Returns whether this popup is active. It is active if the propsal selector is visible.
 	 *
 	 * @return <code>true</code> if this popup is active
 	 */
 	public boolean isActive() {
 		return fProposalShell != null && !fProposalShell.isDisposed();
 	}

 	/**
 	 * Initializes the proposal selector with these given proposals.
 	 *
 	 * @param proposals the proposals
 	 */
 	private void setProposals(ICompletionProposal[] proposals) {
 		if (Helper.okToUse(fProposalTable)) {

 			ICompletionProposal oldProposal= getSelectedProposal();
 			if (oldProposal instanceof ICompletionProposalExtension2)
 				((ICompletionProposalExtension2) oldProposal).unselected(fViewer);

 			fFilteredProposals= proposals;

 			fProposalTable.setRedraw(false);
 			fProposalTable.removeAll();

 			TableItem item;
 			ICompletionProposal p;
 			for (int i= 0; i < proposals.length; i++) {
 				p= proposals[i];
 				item= new TableItem(fProposalTable, SWT.NULL);
 				if (p.getImage() != null)
 					item.setImage(p.getImage());
 				item.setText(p.getDisplayString());
 				item.setData(p);
 			}

 			Point currentLocation= fProposalShell.getLocation();
 			Point newLocation= getLocation();
 			if ((newLocation.x < currentLocation.x && newLocation.y == currentLocation.y) || newLocation.y < currentLocation.y)
 				fProposalShell.setLocation(newLocation);

 			selectProposal(0, false);
 			fProposalTable.setRedraw(true);
 		}
 	}

 	/**
 	 * Returns the graphical location at which this popup should be made visible.
 	 *
 	 * @return the location of this popup
 	 */
 	private Point getLocation() {
 		StyledText text= fViewer.getTextWidget();
 		int caret= text.getCaretOffset();
 		Point p= text.getLocationAtOffset(caret);
 		if (p.x < 0) p.x= 0;
 		if (p.y < 0) p.y= 0;
 		p= new Point(p.x, p.y + text.getLineHeight());
 		p= text.toDisplay(p);
 		if (p.x < 0) p.x= 0;
 		if (p.y < 0) p.y= 0;
 		return p;
 	}

 	/**
 	 *Displays this popup and install the additional info controller, so that additional info
 	 * is displayed when a proposal is selected and additional info is available.
 	 */
 	private void displayProposals() {
 		if (fContentAssistant.addContentAssistListener(this, ContentAssistant.PROPOSAL_SELECTOR)) {
 			fProposalShell.setVisible(true);
 			if (fAdditionalInfoController != null) {
 				fAdditionalInfoController.install(fProposalTable);
 				fAdditionalInfoController.handleTableSelectionChanged();
 			}
 		}
 	}

 	/*
 	 * @see IContentAssistListener#verifyKey(VerifyEvent)
 	 */
 	public boolean verifyKey(VerifyEvent e) {
 		if (!Helper.okToUse(fProposalShell))
 			return true;

 		char key= e.character;
 		if (key == 0) {
 			int newSelection= fProposalTable.getSelectionIndex();
 			int visibleRows= (fProposalTable.getSize().y / fProposalTable.getItemHeight()) - 1;
 			boolean smartToggle= false;
 			switch (e.keyCode) {

 				case SWT.ARROW_LEFT :
 				case SWT.ARROW_RIGHT :
 					filterProposal();
 					return true;

 				case SWT.ARROW_UP :
 					newSelection -= 1;
 					if (newSelection < 0)
 						newSelection= fProposalTable.getItemCount() - 1;
 					break;

 				case SWT.ARROW_DOWN :
 					newSelection += 1;
 					if (newSelection > fProposalTable.getItemCount() - 1)
 						newSelection= 0;
 					break;

 				case SWT.PAGE_DOWN :
 					newSelection += visibleRows;
 					if (newSelection >= fProposalTable.getItemCount())
 						newSelection= fProposalTable.getItemCount() - 1;
 					break;

 				case SWT.PAGE_UP :
 					newSelection -= visibleRows;
 					if (newSelection < 0)
 						newSelection= 0;
 					break;

 				case SWT.HOME :
 					newSelection= 0;
 					break;

 				case SWT.END :
 					newSelection= fProposalTable.getItemCount() - 1;
 					break;

 				default :
 					if (e.keyCode != SWT.MOD1 && e.keyCode != SWT.MOD2 && e.keyCode != SWT.MOD3 && e.keyCode != SWT.MOD4)
 						hide();
 					return true;
 			}

 			selectProposal(newSelection, smartToggle);

 			e.doit= false;
 			return false;

 		} else {

 			switch (key) {
 				case 0x1B: // Esc
 					e.doit= false;
 					hide();
 					break;

 				case '\n': // Ctrl-Enter on w2k
 				case '\r': // Enter
 					e.doit= false;
 					selectProposalWithMask(e.stateMask);
 					break;

 				case '\t':
 					e.doit= false;
 					fProposalShell.setFocus();
 					return false;

 				default:
 					ICompletionProposal p= getSelectedProposal();
 					if (p instanceof ICompletionProposalExtension) {
 						ICompletionProposalExtension t= (ICompletionProposalExtension) p;
 						char[] triggers= t.getTriggerCharacters();
 						if (contains(triggers, key)) {
 							e.doit= false;
 							hide();
 							insertProposal(p, key, e.stateMask, fViewer.getSelectedRange().x);
 						}
 					}
 			}
 		}

 		return true;
 	}

 	/**
 	 * Selects the entry with the given index in the proposal selector and feeds
 	 * the selection to the additional info controller.
 	 *
 	 * @param index the index in the list
 	 * @param smartToggle <code>true</code> if the smart toogle key has been pressed
 	 * @since 2.1
 	 */
 	private void selectProposal(int index, boolean smartToggle) {

 		ICompletionProposal oldProposal= getSelectedProposal();
 		if (oldProposal instanceof ICompletionProposalExtension2)
 			((ICompletionProposalExtension2) oldProposal).unselected(fViewer);

 		ICompletionProposal proposal= fFilteredProposals[index];
 		if (proposal instanceof ICompletionProposalExtension2)
 			((ICompletionProposalExtension2) proposal).selected(fViewer, smartToggle);


 		fProposalTable.setSelection(index);
 		fProposalTable.showSelection();
 		if (fAdditionalInfoController != null)
 			fAdditionalInfoController.handleTableSelectionChanged();
 	}

 	/**
 	 * Returns whether the given character is contained in the given array of
 	 * characters.
 	 *
 	 * @param characters the list of characters
 	 * @param c the character to look for in the list
 	 * @return <code>true</code> if character belongs to the list
 	 * @since 2.0
 	 */
 	private boolean contains(char[] characters, char c) {

 		if (characters == null)
 			return false;

 		for (int i= 0; i < characters.length; i++) {
 			if (c == characters[i])
 				return true;
 		}

 		return false;
 	}

 	/*
 	 * @see IEventConsumer#processEvent(VerifyEvent)
 	 */
 	public void processEvent(VerifyEvent e) {
 		if (!fInserting)
 			filterProposal();
 	}

 	/**
 	 * Filters the displayed proposal based on the given cursor position and the
 	 * offset of the original invocation of the content assistant.
 	 */
 	private void filterProposal() {
 		++ fInvocationCounter;
 		Control control= fViewer.getTextWidget();
 		control.getDisplay().asyncExec(new Runnable() {
 			long fCounter= fInvocationCounter;
 			public void run() {

 				if (fCounter != fInvocationCounter) return;

 				int offset= fViewer.getSelectedRange().x;
 				ICompletionProposal[] proposals= (offset == -1 ? null : computeFilteredProposals(offset));
 				fDocumentEvents.clear();
 				fFilterOffset= offset;

 				if (proposals != null && proposals.length > 0)
 					setProposals(proposals);
 				else
 					hide();
 			}
 		});
 	}

 	/**
 	 * Computes the subset of already computed propsals that are still valid for
 	 * the given offset.
 	 *
 	 * @param offset the offset
 	 * @return the set of filtered proposals
 	 * @since 2.0
 	 */
 	private ICompletionProposal[] computeFilteredProposals(int offset) {

 		if (offset == fInvocationOffset)
 			return fComputedProposals;

 		if (offset < fInvocationOffset) {
 			fInvocationOffset= offset;
 			fComputedProposals= computeProposals(fInvocationOffset);
 			return fComputedProposals;
 		}

 		ICompletionProposal[] proposals= fComputedProposals;
 		if (offset > fFilterOffset)
 			proposals= fFilteredProposals;

 		if (proposals == null)
 			return null;

 		IDocument document= fViewer.getDocument();
 		int length= proposals.length;
 		List filtered= new ArrayList(length);
 		for (int i= 0; i < length; i++) {

 			if (proposals[i] instanceof ICompletionProposalExtension2) {

 				ICompletionProposalExtension2 p= (ICompletionProposalExtension2) proposals[i];

 				try {
 					DocumentEvent event= TextUtilities.mergeProcessedDocumentEvents(fDocumentEvents);
 					if (p.validate(document, offset, event))
 						filtered.add(p);
 				} catch (BadLocationException e) {
 				}

 			} else if (proposals[i] instanceof ICompletionProposalExtension) {

 				ICompletionProposalExtension p= (ICompletionProposalExtension) proposals[i];
 				if (p.isValidFor(document, offset))
 					filtered.add(p);

 			} else {
 				// restore original behavior
 				fInvocationOffset= offset;
 				fComputedProposals= computeProposals(fInvocationOffset);
 				return fComputedProposals;
 			}
 		}

 		ICompletionProposal[] p= new ICompletionProposal[filtered.size()];
 		filtered.toArray(p);
 		return p;
 	}

 }
	/*******************************************************************************
	* Copyright (c) 2000, 2003 IBM Corporation and others.
	* All rights reserved. This program and the accompanying materials
	* are made available under the terms of the Common Public License v1.0
	* which accompanies this distribution, and is available at
	* http://www.eclipse.org/legal/cpl-v10.html
	*
	* Contributors:
	* IBM Corporation - initial API and implementation
	*******************************************************************************/

	package org.eclipse.jface.text.contentassist;


	import java.util.ArrayList;
	import java.util.List;

	import org.eclipse.swt.SWT;
	import org.eclipse.swt.custom.BusyIndicator;
	import org.eclipse.swt.custom.StyledText;
	import org.eclipse.swt.events.ControlEvent;
	import org.eclipse.swt.events.ControlListener;
	import org.eclipse.swt.events.KeyEvent;
	import org.eclipse.swt.events.KeyListener;
	import org.eclipse.swt.events.SelectionEvent;
	import org.eclipse.swt.events.SelectionListener;
	import org.eclipse.swt.events.VerifyEvent;
	import org.eclipse.swt.graphics.Color;
	import org.eclipse.swt.graphics.Point;
	import org.eclipse.swt.layout.GridData;
	import org.eclipse.swt.layout.GridLayout;
	import org.eclipse.swt.widgets.Control;
	import org.eclipse.swt.widgets.Shell;
	import org.eclipse.swt.widgets.Table;
	import org.eclipse.swt.widgets.TableItem;

	import org.eclipse.jface.text.BadLocationException;
	import org.eclipse.jface.text.DocumentEvent;
	import org.eclipse.jface.text.IDocument;
	import org.eclipse.jface.text.IDocumentListener;
	import org.eclipse.jface.text.IRewriteTarget;
	import org.eclipse.jface.text.ITextViewer;
	import org.eclipse.jface.text.ITextViewerExtension;
	import org.eclipse.jface.text.TextUtilities;



	/**
	* This class is used to present proposals to the user. If additional
	* information exists for a proposal, then selecting that proposal
	* will result in the information being displayed in a secondary
	* window.
	*
	* @see org.eclipse.jface.text.contentassist.ICompletionProposal
	* @see org.eclipse.jface.text.contentassist.AdditionalInfoController
	*/
	class CompletionProposalPopup implements IContentAssistListener {

	/** The associated text viewer */
	private ITextViewer fViewer;
	/** The associated content assistant */
	private ContentAssistant fContentAssistant;
	/** The used additional info controller */
	private AdditionalInfoController fAdditionalInfoController;
	/** The closing strategy for this completion proposal popup */
	private PopupCloser fPopupCloser= new PopupCloser();
	/** The popup shell */
	private Shell fProposalShell;
	/** The proposal table */
	private Table fProposalTable;
	/** Indicates whether a completion proposal is being inserted */
	private boolean fInserting= false;
	/** The key listener to control navigation */
	private KeyListener fKeyListener;
	/** List of document events used for filtering proposals */
	private List fDocumentEvents= new ArrayList();
	/** Listener filling the document event queue */
	private IDocumentListener fDocumentListener= new IDocumentListener() {
	public void documentAboutToBeChanged(DocumentEvent event) {}
	public void documentChanged(DocumentEvent event) {
	fDocumentEvents.add(event);
	}
	};
	/** Reentrance count for <code>filterProposals</code> */
	private long fInvocationCounter= 0;
	/** The filter list of proposals */
	private ICompletionProposal[] fFilteredProposals;
	/** The computed list of proposals */
	private ICompletionProposal[] fComputedProposals;
	/** The offset for which the proposals have been computed */
	private int fInvocationOffset;
	/** The offset for which the computed proposaks have been filtered */
	private int fFilterOffset;
	/** The default line delimiter of the viewer's widget */
	private String fLineDelimiter;


	/**
	* Creates a new completion proposal popup for the given elements.
	*
	* @param contentAssistant the content assistant feeding this popup
	* @param viewer the viewer on top of which this popup appears
	* @param infoController the info control collaborating with this popup
	* @since 2.0
	*/
	public CompletionProposalPopup(ContentAssistant contentAssistant, ITextViewer viewer, AdditionalInfoController infoController) {
	fContentAssistant= contentAssistant;
	fViewer= viewer;
	fAdditionalInfoController= infoController;
	}

	/**
	* Computes and presents completion proposals. The flag indicates whether this call has
	* be made out of an auto activation context.
	*
	* @param autoActivated <code>true</code> if auto activation context
	* @return an error message or <code>null</code> in case of no error
	*/
	public String showProposals(final boolean autoActivated) {

	IDocument document= fViewer.getDocument();
	if (document != null)
	document.addDocumentListener(fDocumentListener);

	if (fKeyListener == null) {
	fKeyListener= new KeyListener() {
	public void keyPressed(KeyEvent e) {
	if (!Helper.okToUse(fProposalShell))
	return;

	if (e.character == 0 && e.keyCode == SWT.MOD1) {
	// http://dev.eclipse.org/bugs/show_bug.cgi?id=34754
	int index= fProposalTable.getSelectionIndex();
	if (index >= 0)
	selectProposal(index, true);
	}
	}

	public void keyReleased(KeyEvent e) {
	if (!Helper.okToUse(fProposalShell))
	return;

	if (e.character == 0 && e.keyCode == SWT.MOD1) {
	// http://dev.eclipse.org/bugs/show_bug.cgi?id=34754
	int index= fProposalTable.getSelectionIndex();
	if (index >= 0)
	selectProposal(index, false);
	}
	}
	};
	}

	final StyledText styledText= fViewer.getTextWidget();
	if (styledText != null && !styledText.isDisposed())
	styledText.addKeyListener(fKeyListener);

	BusyIndicator.showWhile(styledText.getDisplay(), new Runnable() {
	public void run() {

	fInvocationOffset= fViewer.getSelectedRange().x;
	fComputedProposals= computeProposals(fInvocationOffset);

	int count= (fComputedProposals == null ? 0 : fComputedProposals.length);
	if (count == 0) {

	if (!autoActivated)
	styledText.getDisplay().beep();

	} else {

	if (count == 1 && !autoActivated && fContentAssistant.isAutoInserting())

	insertProposal(fComputedProposals[0], (char) 0, 0, fInvocationOffset);

	else {

	if (fLineDelimiter == null)
	fLineDelimiter= styledText.getLineDelimiter();

	createProposalSelector();
	setProposals(fComputedProposals);
	displayProposals();
	}
	}
	}
	});

	return getErrorMessage();
	}

	/**
	* Returns the completion proposal available at the given offset of the
	* viewer's document. Delegates the work to the content assistant.
	*
	* @param offset the offset
	* @return the completion proposals available at this offset
	*/
	private ICompletionProposal[] computeProposals(int offset) {
	return fContentAssistant.computeCompletionProposals(fViewer, offset);
	}

	/**
	* Returns the error message.
	*
	* @return the error message
	*/
	private String getErrorMessage() {
	return fContentAssistant.getErrorMessage();
	}

	/**
	* Creates the proposal selector.
	*/
	private void createProposalSelector() {
	if (Helper.okToUse(fProposalShell))
	return;

	Control control= fViewer.getTextWidget();
	fProposalShell= new Shell(control.getShell(), SWT.ON_TOP \| SWT.RESIZE );
	fProposalTable= new Table(fProposalShell, SWT.H_SCROLL \| SWT.V_SCROLL);

	fProposalTable.setLocation(0, 0);
	if (fAdditionalInfoController != null)
	fAdditionalInfoController.setSizeConstraints(50, 10, true, false);

	GridLayout layout= new GridLayout();
	layout.marginWidth= 0;
	layout.marginHeight= 0;
	fProposalShell.setLayout(layout);

	GridData data= new GridData(GridData.FILL_BOTH);
	data.heightHint= fProposalTable.getItemHeight() * 10;
	data.widthHint= 300;
	fProposalTable.setLayoutData(data);

	fProposalShell.pack();

	if (fAdditionalInfoController != null) {
	fProposalShell.addControlListener(new ControlListener() {

	public void controlMoved(ControlEvent e) {}

	public void controlResized(ControlEvent e) {
	// resets the cached resize constraints
	fAdditionalInfoController.setSizeConstraints(50, 10, true, false);
	}
	});
	}

	fProposalShell.setBackground(control.getDisplay().getSystemColor(SWT.COLOR_BLACK));

	Color c= fContentAssistant.getProposalSelectorBackground();
	if (c == null)
	c= control.getDisplay().getSystemColor(SWT.COLOR_INFO_BACKGROUND);
	fProposalTable.setBackground(c);

	c= fContentAssistant.getProposalSelectorForeground();
	if (c == null)
	c= control.getDisplay().getSystemColor(SWT.COLOR_INFO_FOREGROUND);
	fProposalTable.setForeground(c);

	fProposalTable.addSelectionListener(new SelectionListener() {

	public void widgetSelected(SelectionEvent e) {}

	public void widgetDefaultSelected(SelectionEvent e) {
	selectProposalWithMask(e.stateMask);
	}
	});
	// if (fKeyListener != null)
	// fProposalTable.addKeyListener(fKeyListener);

	fPopupCloser.install(fContentAssistant, fProposalTable);

	fProposalTable.setHeaderVisible(false);
	fContentAssistant.addToLayout(this, fProposalShell, ContentAssistant.LayoutManager.LAYOUT_PROPOSAL_SELECTOR, fContentAssistant.getSelectionOffset());
	}

	/**
	* Returns the proposal selected in the proposal selector.
	*
	* @return the selected proposal
	* @since 2.0
	*/
	private ICompletionProposal getSelectedProposal() {
	int i= fProposalTable.getSelectionIndex();
	if (i < 0 \|\| i >= fFilteredProposals.length)
	return null;
	return fFilteredProposals[i];
	}

	/**
	* Takes the selected proposal and applies it.
	*
	* @param stateMask the state mask
	* @since 2.1
	*/
	private void selectProposalWithMask(int stateMask) {
	ICompletionProposal p= getSelectedProposal();
	hide();
	if (p != null)
	insertProposal(p, (char) 0, stateMask, fViewer.getSelectedRange().x);
	}

	/**
	* Applies the given proposal at the given offset. The given character is the
	* one that triggered the insertion of this proposal.
	*
	* @param p the completion proposal
	* @param trigger the trigger character
	* @param offset the offset
	* @since 2.1
	*/
	private void insertProposal(ICompletionProposal p, char trigger, int stateMask, int offset) {

	fInserting= true;
	IRewriteTarget target= null;

	try {

	IDocument document= fViewer.getDocument();

	if (fViewer instanceof ITextViewerExtension) {
	ITextViewerExtension extension= (ITextViewerExtension) fViewer;
	target= extension.getRewriteTarget();
	}

	if (target != null)
	target.beginCompoundChange();

	if (p instanceof ICompletionProposalExtension2) {
	ICompletionProposalExtension2 e= (ICompletionProposalExtension2) p;
	e.apply(fViewer, trigger, stateMask, offset);
	} else if (p instanceof ICompletionProposalExtension) {
	ICompletionProposalExtension e= (ICompletionProposalExtension) p;
	e.apply(document, trigger, offset);
	} else {
	p.apply(document);
	}

	Point selection= p.getSelection(document);
	if (selection != null) {
	fViewer.setSelectedRange(selection.x, selection.y);
	fViewer.revealRange(selection.x, selection.y);
	}

	IContextInformation info= p.getContextInformation();
	if (info != null) {

	int position;
	if (p instanceof ICompletionProposalExtension) {
	ICompletionProposalExtension e= (ICompletionProposalExtension) p;
	position= e.getContextInformationPosition();
	} else {
	if (selection == null)
	selection= fViewer.getSelectedRange();
	position= selection.x + selection.y;
	}

	fContentAssistant.showContextInformation(info, position);
	}

	} finally {
	if (target != null)
	target.endCompoundChange();
	fInserting= false;
	}
	}

	/**
	* Returns whether this popup has the focus.
	*
	* @return <code>true</code> if the popup has the focus
	*/
	public boolean hasFocus() {
	if (Helper.okToUse(fProposalShell))
	return (fProposalShell.isFocusControl() \|\| fProposalTable.isFocusControl());

	return false;
	}

	/**
	* Hides this popup.
	*/
	public void hide() {

	IDocument document= fViewer.getDocument();
	if (document != null)
	document.removeDocumentListener(fDocumentListener);
	fDocumentEvents.clear();

	StyledText styledText= fViewer.getTextWidget();
	if (fKeyListener != null && styledText != null && !styledText.isDisposed())
	styledText.removeKeyListener(fKeyListener);

	if (Helper.okToUse(fProposalTable)) {
	ICompletionProposal proposal= getSelectedProposal();
	if (proposal instanceof ICompletionProposalExtension2) {
	ICompletionProposalExtension2 extension= (ICompletionProposalExtension2) proposal;
	extension.unselected(fViewer);
	}
	// if (fKeyListener != null)
	// fProposalTable.removeKeyListener(fKeyListener);
	}

	if (Helper.okToUse(fProposalShell)) {

	fContentAssistant.removeContentAssistListener(this, ContentAssistant.PROPOSAL_SELECTOR);

	fPopupCloser.uninstall();
	fProposalShell.setVisible(false);
	fProposalShell.dispose();
	fProposalShell= null;
	}

	fFilteredProposals= null;

	fContentAssistant.possibleCompletionsClosed();
	}

	/**
	*Returns whether this popup is active. It is active if the propsal selector is visible.
	*
	* @return <code>true</code> if this popup is active
	*/
	public boolean isActive() {
	return fProposalShell != null && !fProposalShell.isDisposed();
	}

	/**
	* Initializes the proposal selector with these given proposals.
	*
	* @param proposals the proposals
	*/
	private void setProposals(ICompletionProposal[] proposals) {
	if (Helper.okToUse(fProposalTable)) {

	ICompletionProposal oldProposal= getSelectedProposal();
	if (oldProposal instanceof ICompletionProposalExtension2)
	((ICompletionProposalExtension2) oldProposal).unselected(fViewer);

	fFilteredProposals= proposals;

	fProposalTable.setRedraw(false);
	fProposalTable.removeAll();

	TableItem item;
	ICompletionProposal p;
	for (int i= 0; i < proposals.length; i++) {
	p= proposals[i];
	item= new TableItem(fProposalTable, SWT.NULL);
	if (p.getImage() != null)
	item.setImage(p.getImage());
	item.setText(p.getDisplayString());
	item.setData(p);
	}

	Point currentLocation= fProposalShell.getLocation();
	Point newLocation= getLocation();
	if ((newLocation.x < currentLocation.x && newLocation.y == currentLocation.y) \|\| newLocation.y < currentLocation.y)
	fProposalShell.setLocation(newLocation);

	selectProposal(0, false);
	fProposalTable.setRedraw(true);
	}
	}

	/**
	* Returns the graphical location at which this popup should be made visible.
	*
	* @return the location of this popup
	*/
	private Point getLocation() {
	StyledText text= fViewer.getTextWidget();
	int caret= text.getCaretOffset();
	Point p= text.getLocationAtOffset(caret);
	if (p.x < 0) p.x= 0;
	if (p.y < 0) p.y= 0;
	p= new Point(p.x, p.y + text.getLineHeight());
	p= text.toDisplay(p);
	if (p.x < 0) p.x= 0;
	if (p.y < 0) p.y= 0;
	return p;
	}

	/**
	*Displays this popup and install the additional info controller, so that additional info
	* is displayed when a proposal is selected and additional info is available.
	*/
	private void displayProposals() {
	if (fContentAssistant.addContentAssistListener(this, ContentAssistant.PROPOSAL_SELECTOR)) {
	fProposalShell.setVisible(true);
	if (fAdditionalInfoController != null) {
	fAdditionalInfoController.install(fProposalTable);
	fAdditionalInfoController.handleTableSelectionChanged();
	}
	}
	}

	/*
	* @see IContentAssistListener#verifyKey(VerifyEvent)
	*/
	public boolean verifyKey(VerifyEvent e) {
	if (!Helper.okToUse(fProposalShell))
	return true;

	char key= e.character;
	if (key == 0) {
	int newSelection= fProposalTable.getSelectionIndex();
	int visibleRows= (fProposalTable.getSize().y / fProposalTable.getItemHeight()) - 1;
	boolean smartToggle= false;
	switch (e.keyCode) {

	case SWT.ARROW_LEFT :
	case SWT.ARROW_RIGHT :
	filterProposal();
	return true;

	case SWT.ARROW_UP :
	newSelection -= 1;
	if (newSelection < 0)
	newSelection= fProposalTable.getItemCount() - 1;
	break;

	case SWT.ARROW_DOWN :
	newSelection += 1;
	if (newSelection > fProposalTable.getItemCount() - 1)
	newSelection= 0;
	break;

	case SWT.PAGE_DOWN :
	newSelection += visibleRows;
	if (newSelection >= fProposalTable.getItemCount())
	newSelection= fProposalTable.getItemCount() - 1;
	break;

	case SWT.PAGE_UP :
	newSelection -= visibleRows;
	if (newSelection < 0)
	newSelection= 0;
	break;

	case SWT.HOME :
	newSelection= 0;
	break;

	case SWT.END :
	newSelection= fProposalTable.getItemCount() - 1;
	break;

	default :
	if (e.keyCode != SWT.MOD1 && e.keyCode != SWT.MOD2 && e.keyCode != SWT.MOD3 && e.keyCode != SWT.MOD4)
	hide();
	return true;
	}

	selectProposal(newSelection, smartToggle);

	e.doit= false;
	return false;

	} else {

	switch (key) {
	case 0x1B: // Esc
	e.doit= false;
	hide();
	break;

	case '\n': // Ctrl-Enter on w2k
	case '\r': // Enter
	e.doit= false;
	selectProposalWithMask(e.stateMask);
	break;

	case '\t':
	e.doit= false;
	fProposalShell.setFocus();
	return false;

	default:
	ICompletionProposal p= getSelectedProposal();
	if (p instanceof ICompletionProposalExtension) {
	ICompletionProposalExtension t= (ICompletionProposalExtension) p;
	char[] triggers= t.getTriggerCharacters();
	if (contains(triggers, key)) {
	e.doit= false;
	hide();
	insertProposal(p, key, e.stateMask, fViewer.getSelectedRange().x);
	}
	}
	}
	}

	return true;
	}

	/**
	* Selects the entry with the given index in the proposal selector and feeds
	* the selection to the additional info controller.
	*
	* @param index the index in the list
	* @param smartToggle <code>true</code> if the smart toogle key has been pressed
	* @since 2.1
	*/
	private void selectProposal(int index, boolean smartToggle) {

	ICompletionProposal oldProposal= getSelectedProposal();
	if (oldProposal instanceof ICompletionProposalExtension2)
	((ICompletionProposalExtension2) oldProposal).unselected(fViewer);

	ICompletionProposal proposal= fFilteredProposals[index];
	if (proposal instanceof ICompletionProposalExtension2)
	((ICompletionProposalExtension2) proposal).selected(fViewer, smartToggle);


	fProposalTable.setSelection(index);
	fProposalTable.showSelection();
	if (fAdditionalInfoController != null)
	fAdditionalInfoController.handleTableSelectionChanged();
	}

	/**
	* Returns whether the given character is contained in the given array of
	* characters.
	*
	* @param characters the list of characters
	* @param c the character to look for in the list
	* @return <code>true</code> if character belongs to the list
	* @since 2.0
	*/
	private boolean contains(char[] characters, char c) {

	if (characters == null)
	return false;

	for (int i= 0; i < characters.length; i++) {
	if (c == characters[i])
	return true;
	}

	return false;
	}

	/*
	* @see IEventConsumer#processEvent(VerifyEvent)
	*/
	public void processEvent(VerifyEvent e) {
	if (!fInserting)
	filterProposal();
	}

	/**
	* Filters the displayed proposal based on the given cursor position and the
	* offset of the original invocation of the content assistant.
	*/
	private void filterProposal() {
	++ fInvocationCounter;
	Control control= fViewer.getTextWidget();
	control.getDisplay().asyncExec(new Runnable() {
	long fCounter= fInvocationCounter;
	public void run() {

	if (fCounter != fInvocationCounter) return;

	int offset= fViewer.getSelectedRange().x;
	ICompletionProposal[] proposals= (offset == -1 ? null : computeFilteredProposals(offset));
	fDocumentEvents.clear();
	fFilterOffset= offset;

	if (proposals != null && proposals.length > 0)
	setProposals(proposals);
	else
	hide();
	}
	});
	}

	/**
	* Computes the subset of already computed propsals that are still valid for
	* the given offset.
	*
	* @param offset the offset
	* @return the set of filtered proposals
	* @since 2.0
	*/
	private ICompletionProposal[] computeFilteredProposals(int offset) {

	if (offset == fInvocationOffset)
	return fComputedProposals;

	if (offset < fInvocationOffset) {
	fInvocationOffset= offset;
	fComputedProposals= computeProposals(fInvocationOffset);
	return fComputedProposals;
	}

	ICompletionProposal[] proposals= fComputedProposals;
	if (offset > fFilterOffset)
	proposals= fFilteredProposals;

	if (proposals == null)
	return null;

	IDocument document= fViewer.getDocument();
	int length= proposals.length;
	List filtered= new ArrayList(length);
	for (int i= 0; i < length; i++) {

	if (proposals[i] instanceof ICompletionProposalExtension2) {

	ICompletionProposalExtension2 p= (ICompletionProposalExtension2) proposals[i];

	try {
	DocumentEvent event= TextUtilities.mergeProcessedDocumentEvents(fDocumentEvents);
	if (p.validate(document, offset, event))
	filtered.add(p);
	} catch (BadLocationException e) {
	}

	} else if (proposals[i] instanceof ICompletionProposalExtension) {

	ICompletionProposalExtension p= (ICompletionProposalExtension) proposals[i];
	if (p.isValidFor(document, offset))
	filtered.add(p);

	} else {
	// restore original behavior
	fInvocationOffset= offset;
	fComputedProposals= computeProposals(fInvocationOffset);
	return fComputedProposals;
	}
	}

	ICompletionProposal[] p= new ICompletionProposal[filtered.size()];
	filtered.toArray(p);
	return p;
	}

	}