org.eclipse.wst.common.snippets/src/org/eclipse/wst/common/snippets/internal/editors/VariableItemEditor.java - webtools-common/webtools.common.snippets - Git at Google

 /*******************************************************************************
  * Copyright (c) 2004 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
  *******************************************************************************/
 package org.eclipse.wst.common.snippets.internal.editors;

 import com.ibm.icu.text.Collator;
 import java.util.ArrayList;
 import java.util.Iterator;
 import java.util.List;

 import org.eclipse.jface.text.BadLocationException;
 import org.eclipse.jface.text.Document;
 import org.eclipse.jface.text.IDocument;
 import org.eclipse.jface.text.ITextOperationTarget;
 import org.eclipse.jface.text.ITextViewer;
 import org.eclipse.jface.text.contentassist.ContentAssistant;
 import org.eclipse.jface.text.contentassist.ICompletionProposal;
 import org.eclipse.jface.text.contentassist.IContentAssistProcessor;
 import org.eclipse.jface.text.contentassist.IContentAssistant;
 import org.eclipse.jface.text.contentassist.IContextInformation;
 import org.eclipse.jface.text.contentassist.IContextInformationValidator;
 import org.eclipse.jface.text.source.ISourceViewer;
 import org.eclipse.jface.text.source.SourceViewer;
 import org.eclipse.jface.text.source.SourceViewerConfiguration;
 import org.eclipse.jface.viewers.ISelectionChangedListener;
 import org.eclipse.jface.viewers.SelectionChangedEvent;
 import org.eclipse.swt.SWT;
 import org.eclipse.swt.accessibility.ACC;
 import org.eclipse.swt.accessibility.AccessibleAdapter;
 import org.eclipse.swt.accessibility.AccessibleEvent;
 import org.eclipse.swt.custom.StyledText;
 import org.eclipse.swt.custom.VerifyKeyListener;
 import org.eclipse.swt.events.ModifyEvent;
 import org.eclipse.swt.events.ModifyListener;
 import org.eclipse.swt.events.SelectionAdapter;
 import org.eclipse.swt.events.SelectionEvent;
 import org.eclipse.swt.events.SelectionListener;
 import org.eclipse.swt.events.VerifyEvent;
 import org.eclipse.swt.events.VerifyListener;
 import org.eclipse.swt.graphics.Image;
 import org.eclipse.swt.graphics.Point;
 import org.eclipse.swt.layout.GridData;
 import org.eclipse.swt.layout.GridLayout;
 import org.eclipse.swt.widgets.Button;
 import org.eclipse.swt.widgets.Composite;
 import org.eclipse.swt.widgets.Control;
 import org.eclipse.swt.widgets.Label;
 import org.eclipse.ui.PlatformUI;
 import org.eclipse.wst.common.snippets.core.ISnippetItem;
 import org.eclipse.wst.common.snippets.core.ISnippetVariable;
 import org.eclipse.wst.common.snippets.internal.IHelpContextIds;
 import org.eclipse.wst.common.snippets.internal.Logger;
 import org.eclipse.wst.common.snippets.internal.SnippetsMessages;
 import org.eclipse.wst.common.snippets.internal.palette.SnippetPaletteItem;
 import org.eclipse.wst.common.snippets.internal.palette.SnippetVariable;
 import org.eclipse.wst.common.snippets.internal.ui.StringPropertyTableViewer;
 import org.eclipse.wst.common.snippets.internal.ui.ValueChangedListener;
 import org.eclipse.wst.common.snippets.internal.util.Sorter;
 import org.eclipse.wst.common.snippets.internal.util.StringUtils;

 /**
  * A snippet item editor that can define snippet variables
  */
 public class VariableItemEditor implements ISnippetEditor {
 	private static class CompletionProposalSorter extends Sorter {
 		Collator collator = Collator.getInstance();

 		public boolean compare(Object elementOne, Object elementTwo) {
 			/**
 			 * Returns true if elementTwo is 'greater than' elementOne This is
 			 * the 'ordering' method of the sort operation. Each subclass
 			 * overides this method with the particular implementation of the
 			 * 'greater than' concept for the objects being sorted.
 			 */
 			ICompletionProposal proposal1 = (ICompletionProposal) elementOne;
 			ICompletionProposal proposal2 = (ICompletionProposal) elementTwo;
 			return (collator.compare(proposal1.getDisplayString(), proposal2.getDisplayString())) < 0;
 		}
 	}

 	private class ItemEditorSourceViewerConfiguration extends SourceViewerConfiguration {
 		private IContentAssistProcessor fProcessor = null;

 		public ItemEditorSourceViewerConfiguration() {
 			super();
 			fProcessor = new IContentAssistProcessor() {
 				char[] autochars = new char[]{};

 				public ICompletionProposal[] computeCompletionProposals(ITextViewer viewer, int documentOffset) {
 					java.util.List vars = new ArrayList();
 					final ITextViewer textViewer = viewer;
 					Iterator keys = fTableViewer.getColumnData()[0].keySet().iterator();
 					while (keys.hasNext()) {
 						Object key = keys.next();
 						final String varID = (String) fTableViewer.getColumnData()[0].get(key);
 						if (varID != null) {
 							ICompletionProposal p = new ICompletionProposal() {
 								protected int fReplacementOffset = textViewer.getSelectedRange().x;
 								protected String varname = varID;

 								public void apply(IDocument document) {
 									try {
 										document.replace(textViewer.getSelectedRange().x, 0, "${" + getDisplayString() + "}"); //$NON-NLS-1$ //$NON-NLS-2$
 									}
 									catch (BadLocationException e) {
 										Logger.logException(e);
 									}
 								}

 								public String getAdditionalProposalInfo() {
 									return null;
 								}

 								public IContextInformation getContextInformation() {
 									return null;
 								}

 								public String getDisplayString() {
 									String display = varname;
 									if (display == null)
 										display = ""; //$NON-NLS-1$
 									return display;
 								}

 								public Image getImage() {
 									return null;
 								}

 								public Point getSelection(IDocument document) {
 									return new Point(fReplacementOffset + 3 + getDisplayString().length(), 0);
 								}
 							};
 							vars.add(p);
 						}
 					}
 					ICompletionProposal[] proposals = new ICompletionProposal[vars.size()];
 					vars.toArray(proposals);
 					return sortProposals(proposals);
 				}

 				public IContextInformation[] computeContextInformation(ITextViewer viewer, int documentOffset) {
 					return null;
 				}

 				public char[] getCompletionProposalAutoActivationCharacters() {
 					return autochars;
 				}

 				public char[] getContextInformationAutoActivationCharacters() {
 					return null;
 				}

 				public IContextInformationValidator getContextInformationValidator() {
 					return null;
 				}

 				public String getErrorMessage() {
 					return null;
 				}

 				public ICompletionProposal[] sortProposals(ICompletionProposal[] proposals) {
 					if (proposals == null || proposals.length == 0)
 						return proposals;
 					Object sortedProposals[] = new CompletionProposalSorter().sort(proposals);
 					List sortedList = new ArrayList();
 					for (int i = 0; i < sortedProposals.length; i++)
 						sortedList.add(sortedProposals[i]);
 					ICompletionProposal[] results = new ICompletionProposal[sortedProposals.length];
 					sortedList.toArray(results);
 					return results;
 				}
 			};
 		}

 		/*
 		 * @see SourceViewerConfiguration#getContentAssistant(ISourceViewer)
 		 */
 		public IContentAssistant getContentAssistant(ISourceViewer sourceViewer) {
 			ContentAssistant assistant = new ContentAssistant();
 			assistant.setContentAssistProcessor(fProcessor, IDocument.DEFAULT_CONTENT_TYPE);

 			assistant.enableAutoActivation(false);
 			assistant.setAutoActivationDelay(500);
 			assistant.setProposalPopupOrientation(IContentAssistant.PROPOSAL_OVERLAY);
 			assistant.setContextInformationPopupOrientation(IContentAssistant.CONTEXT_INFO_ABOVE);

 			// Color background= something;
 			// assistant.setContextInformationPopupBackground(background);
 			// assistant.setContextSelectorBackground(background);
 			// assistant.setProposalSelectorBackground(background);

 			return assistant;
 		}
 	}

 	protected StyledText content = null;
 	protected SnippetPaletteItem fItem = null;
 	protected StringPropertyTableViewer fTableViewer = null;
 	private ModifyListener modifyListener = null;

 	protected java.util.List modifyListeners = null;

 	public VariableItemEditor() {
 		super();
 	}

 	public void addModifyListener(ModifyListener listener) {
 		getListeners().add(listener);
 	}

 	public Control createContents(Composite parent) {
 		// create the contents of the variable editing dialog

 		// the container for the variables fTableViewer and new/remove buttons
 		PlatformUI.getWorkbench().getHelpSystem().setHelp(parent, IHelpContextIds.DIALOG_EDIT_VARITEM);

 		Composite variableComposite = new Composite(parent, SWT.NONE);
 		variableComposite.setLayoutData(new GridData(GridData.FILL_HORIZONTAL));
 		((GridData) variableComposite.getLayoutData()).widthHint = parent.getDisplay().getClientArea().width / 3;
 		GridLayout sublayout = new GridLayout();
 		sublayout.numColumns = 2;
 		sublayout.marginWidth = 0;
 		sublayout.makeColumnsEqualWidth = false;
 		variableComposite.setLayout(sublayout);

 		Label nameLabel = new Label(variableComposite, SWT.NONE);
 		nameLabel.setText(SnippetsMessages.Variables__4); //$NON-NLS-1$
 		GridData doubleData = new GridData(GridData.FILL_HORIZONTAL);
 		nameLabel.setLayoutData(doubleData);

 		Label throwAway = new Label(variableComposite, SWT.NONE);
 		throwAway.setLayoutData(new GridData());

 		// saved and made final here to update the template text area below
 		final String nameProperty = SnippetsMessages.Name_5; //$NON-NLS-1$
 		fTableViewer = new StringPropertyTableViewer();
 		fTableViewer.setColumnNames(new String[]{nameProperty, SnippetsMessages.Description_6, SnippetsMessages.Default_Value_7}); //$NON-NLS-1$ //$NON-NLS-2$
 		fTableViewer.createContents(variableComposite);

 		GridData data = new GridData(GridData.FILL_HORIZONTAL | GridData.GRAB_HORIZONTAL);
 		data.heightHint = fTableViewer.getTable().getItemHeight() * 6;
 		fTableViewer.getControl().setLayoutData(data);

 		// For now, each column gets its data from a separate hashtable. In
 		// each,
 		// the key is the ID of the variable with the values being the name,
 		// description, and default value.
 		ISnippetVariable[] variables = fItem.getVariables();
 		for (int i = 0; i < variables.length; i++) {
 			SnippetVariable var = (SnippetVariable) variables[i];
 			fTableViewer.getColumnData()[0].put(var.getId(), var.getName());
 			if (var.getDescription() != null)
 				fTableViewer.getColumnData()[1].put(var.getId(), var.getDescription());
 			else
 				fTableViewer.getColumnData()[1].put(var.getId(), ""); //$NON-NLS-1$
 			if (var.getDefaultValue() != null)
 				fTableViewer.getColumnData()[2].put(var.getId(), var.getDefaultValue());
 			else
 				fTableViewer.getColumnData()[2].put(var.getId(), ""); //$NON-NLS-1$
 		}
 		fTableViewer.refresh();

 		Composite variableButtons = new Composite(variableComposite, SWT.NULL);
 		variableButtons.setLayoutData(new GridData(GridData.VERTICAL_ALIGN_BEGINNING | GridData.HORIZONTAL_ALIGN_END));
 		variableButtons.setLayout(new GridLayout());

 		// Add the New button with a listener to add a new variable without
 		// user
 		// input.
 		// TODO: for usability, throw up a dialog in the middle
 		Button addButton = new Button(variableButtons, SWT.PUSH);
 		addButton.setText(SnippetsMessages.New_1); //$NON-NLS-1$
 		addButton.setLayoutData(new GridData(GridData.FILL_HORIZONTAL));
 		addButton.addSelectionListener(new SelectionListener() {
 			public void widgetDefaultSelected(SelectionEvent e) {
 				widgetSelected(e);
 			}

 			public void widgetSelected(SelectionEvent e) {
 				int i = 1;
 				String newId = "name_" + i++; //$NON-NLS-1$
 				while (fTableViewer.getColumnData()[0].keySet().contains(newId)) {
 					newId = "name_" + i++; //$NON-NLS-1$
 				}
 				fTableViewer.getColumnData()[0].put(newId, newId);
 				fTableViewer.getColumnData()[1].put(newId, ""); //$NON-NLS-1$
 				fTableViewer.getColumnData()[2].put(newId, ""); //$NON-NLS-1$
 				fTableViewer.refresh();
 			}
 		});
 		// add the Remove button with a listener to enable it only when a
 		// cell is selected and in focus
 		final Button removeButton = new Button(variableButtons, SWT.PUSH);
 		removeButton.setText(SnippetsMessages.Remove_15); //$NON-NLS-1$
 		removeButton.setLayoutData(new GridData(GridData.FILL_HORIZONTAL));

 		nameLabel = new Label(parent, SWT.NONE);
 		nameLabel.setText(SnippetsMessages.Template_Pattern__16); //$NON-NLS-1$
 		nameLabel.setLayoutData(new GridData(GridData.FILL_HORIZONTAL));

 		// create a source viewer for to edit the text (makes it easier to
 		// hook into content assist)
 		final SourceViewer sourceViewer = new SourceViewer(parent, null, SWT.BORDER | SWT.V_SCROLL | SWT.H_SCROLL);
 		sourceViewer.setEditable(true);

 		// Update EOLs bug 80231
 		String systemEOL = System.getProperty("line.separator"); //$NON-NLS-1$
 		String text = StringUtils.replace(fItem.getContentString(), "\r\n", "\n"); //$NON-NLS-1$ //$NON-NLS-2$
 		text = StringUtils.replace(text, "\r", "\n"); //$NON-NLS-1$ //$NON-NLS-2$
 		if (!"\n".equals(systemEOL) && systemEOL != null) { //$NON-NLS-1$
 			text = StringUtils.replace(text, "\n", systemEOL); //$NON-NLS-1$
 		}
 		sourceViewer.setDocument(new Document(text));

 		final SourceViewerConfiguration sourceViewerConfiguration = new ItemEditorSourceViewerConfiguration();
 		sourceViewer.configure(sourceViewerConfiguration);
 		content = sourceViewer.getTextWidget();
 		content.addModifyListener(getModifyListener());

 		// add a listener to the Remove button to remove the variable
 		// corresponding to the selected row
 		removeButton.addSelectionListener(new SelectionListener() {
 			public void widgetDefaultSelected(SelectionEvent e) {
 				widgetSelected(e);
 			}

 			public void widgetSelected(SelectionEvent e) {
 				Object id = fTableViewer.getSelection();
 				if (id == null)
 					return;
 				// remove from template as well
 				Object varKey = fTableViewer.getColumnData()[0].get(id);
 				String template = sourceViewer.getDocument().get();
 				sourceViewer.getDocument().set(StringUtils.replace(template, "${" + varKey + "}", "")); //$NON-NLS-1$ //$NON-NLS-2$ //$NON-NLS-3$
 				fTableViewer.getColumnData()[0].remove(id);
 				fTableViewer.getColumnData()[1].remove(id);
 				fTableViewer.getColumnData()[2].remove(id);

 				// #222898, clear selection so that SWT errors are avoided
 				fTableViewer.getTable().setSelection(new int[0]);

 				fTableViewer.refresh();
 				removeButton.setEnabled(false);
 			}
 		});

 		GridData contentData = new GridData(GridData.FILL_BOTH);
 		contentData.heightHint = parent.getDisplay().getClientArea().height / 5;
 		content.setLayoutData(contentData);
 		content.setFont(org.eclipse.jface.resource.JFaceResources.getTextFont());
 		content.setHorizontalPixel(2);
 		// add a verify key listener to trigger the source viewer's undo
 		// action
 		content.addVerifyKeyListener(new VerifyKeyListener() {
 			public void verifyKey(VerifyEvent event) {
 				if (!event.doit)
 					return;
 				boolean doContentAssistOperation = (event.stateMask == SWT.CTRL && event.character == ' ');
 				if (doContentAssistOperation) {
 					sourceViewer.doOperation(ISourceViewer.CONTENTASSIST_PROPOSALS);
 					event.doit = false;
 				}
 				// CTRL-Z (derived from the JDT template editor's way of
 				// assigning the event.character)
 				else if (event.stateMask == SWT.CTRL && (event.character == ('z' - 'a' + 1))) {
 					sourceViewer.doOperation(ITextOperationTarget.UNDO);
 					event.doit = false;
 				}
 			}
 		});
 		// add a verify listener to trigger the source viewer's content assist
 		// and undo actions
 		// TODO: determine if this is duplicated effort
 		content.addVerifyListener(new VerifyListener() {
 			public void verifyText(VerifyEvent event) {
 				if (!event.doit || !((event.stateMask & SWT.CTRL) == 1))
 					return;
 				boolean doContentAssistOperation = (event.stateMask == SWT.CTRL && event.character == ' ');
 				// prevent inserting a space character when content assist is
 				// invoked
 				if (doContentAssistOperation) {
 					event.doit = false;
 				}
 				// CTRL-Z
 				else if (event.stateMask == SWT.CTRL && event.character == ('z' - 'a' + 1)) {
 					event.doit = false;
 				}
 			}
 		});

 		// specifically associate the template pattern label w/ the content
 		// styled text so screen reader reads it
 		setAccessible(content, SnippetsMessages.Template_Pattern__16); //$NON-NLS-1$

 		// add a value change listener to the fTableViewer so that changes to
 		// the name property of a variable
 		// will rewrite the template text to use the new name immediately
 		// TODO: verify with the user that this is OK with them
 		fTableViewer.addValueChangedListener(new ValueChangedListener() {
 			public void valueChanged(String key, String property, String oldValue, String newValue) {
 				if (property.equals(nameProperty)) {
 					String newText = StringUtils.replace(content.getText(), "${" + oldValue + "}", "${" + newValue + "}"); //$NON-NLS-1$ //$NON-NLS-2$ //$NON-NLS-3$ //$NON-NLS-4$
 					content.setText(newText);
 				}
 			}
 		});

 		/*
 		 * Add the "Insert Variable Placeholder" button to invoke content
 		 * assist like the JDT Template editor.
 		 *
 		 * I'm not sure I like this idea as it's mostly a crutch for not
 		 * making content assist obviously available in the source viewer.
 		 */
 		final Button insertVariableButton = new Button(parent, SWT.PUSH);
 		insertVariableButton.setText(SnippetsMessages.Insert_Variable_17); //$NON-NLS-1$
 		insertVariableButton.setLayoutData(new GridData(GridData.HORIZONTAL_ALIGN_BEGINNING | GridData.VERTICAL_ALIGN_BEGINNING));
 		insertVariableButton.setEnabled(fTableViewer.getTable().getItemCount() > 0);
 		insertVariableButton.addSelectionListener(new SelectionListener() {
 			public void widgetDefaultSelected(SelectionEvent e) {
 				widgetSelected(e);
 			}

 			public void widgetSelected(SelectionEvent e) {
 				// JDT template editor invokes Content Assist on a
 				// configured Java Source Viewer. Not that simple here.
 				sourceViewer.getTextWidget().setFocus();
 				sourceViewer.doOperation(ISourceViewer.CONTENTASSIST_PROPOSALS);
 			}
 		});

 		fTableViewer.addSelectionChangedListener(new ISelectionChangedListener() {
 			public void selectionChanged(SelectionChangedEvent event) {
 				insertVariableButton.setEnabled(fTableViewer.getTable().getItemCount() > 0);
 				removeButton.setEnabled(fTableViewer.getControl().isFocusControl() && event.getSelection() != null && (!event.getSelection().isEmpty()));
 			}
 		});

 		addButton.addSelectionListener(new SelectionAdapter() {
 			public void widgetSelected(SelectionEvent e) {
 				insertVariableButton.setEnabled(true);
 			}
 		});
 		removeButton.addSelectionListener(new SelectionAdapter() {
 			public void widgetDefaultSelected(SelectionEvent e) {
 				insertVariableButton.setEnabled(fTableViewer.getTable().getItemCount() > 0);
 			}

 			public void widgetSelected(SelectionEvent e) {
 				insertVariableButton.setEnabled(fTableViewer.getTable().getItemCount() > 0);
 			}
 		});
 		// set the initial enabled state
 		removeButton.setEnabled(false);

 		return parent;
 	}

 	protected void fireModification(ModifyEvent e) {
 		Iterator i = getListeners().iterator();
 		updateItem();
 		while (i.hasNext())
 			((ModifyListener) (i.next())).modifyText(e);
 	}

 	public ISnippetItem getItem() {
 		return fItem;
 	}

 	private java.util.List getListeners() {
 		if (modifyListeners == null)
 			modifyListeners = new ArrayList();
 		return modifyListeners;
 	}

 	protected ModifyListener getModifyListener() {
 		if (modifyListener == null) {
 			modifyListener = new ModifyListener() {
 				public void modifyText(ModifyEvent e) {
 					fireModification(e);
 				}
 			};
 		}
 		return modifyListener;
 	}

 	public void removeModifyListener(ModifyListener listener) {
 		getListeners().remove(listener);
 	}

 	/**
 	 * Specifically set the reporting name of a control for accessibility
 	 */
 	private void setAccessible(Control control, String name) {
 		if (control == null)
 			return;
 		final String n = name;
 		control.getAccessible().addAccessibleListener(new AccessibleAdapter() {
 			public void getName(AccessibleEvent e) {
 				if (e.childID == ACC.CHILDID_SELF)
 					e.result = n;
 			}
 		});
 	}

 	public void setItem(SnippetPaletteItem item) {
 		fItem = item;
 	}

 	public void updateItem() {
 		String text = content.getText();
 		// Update related to bug 80231
 		text = StringUtils.replace(text, "\r\n", "\n"); //$NON-NLS-1$ //$NON-NLS-2$
 		text = StringUtils.replace(text, "\r", "\n"); //$NON-NLS-1$ //$NON-NLS-2$
 		fItem.setContentString(text);

 		ISnippetVariable[] variables = fItem.getVariables();
 		for (int i = 0; i < variables.length; i++) {
 			fItem.removeVariable(variables[i]);
 		}
 		Iterator ids = fTableViewer.getColumnData()[0].keySet().iterator();
 		while (ids.hasNext()) {
 			Object key = ids.next();
 			SnippetVariable var = new SnippetVariable();
 			var.setId((String) key);
 			var.setName((String) fTableViewer.getColumnData()[0].get(key));
 			var.setDescription((String) fTableViewer.getColumnData()[1].get(key));
 			var.setDefaultValue((String) fTableViewer.getColumnData()[2].get(key));
 			fItem.addVariable(var);
 		}
 	}
 }
	/*******************************************************************************
	* Copyright (c) 2004 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
	*******************************************************************************/
	package org.eclipse.wst.common.snippets.internal.editors;

	import com.ibm.icu.text.Collator;
	import java.util.ArrayList;
	import java.util.Iterator;
	import java.util.List;

	import org.eclipse.jface.text.BadLocationException;
	import org.eclipse.jface.text.Document;
	import org.eclipse.jface.text.IDocument;
	import org.eclipse.jface.text.ITextOperationTarget;
	import org.eclipse.jface.text.ITextViewer;
	import org.eclipse.jface.text.contentassist.ContentAssistant;
	import org.eclipse.jface.text.contentassist.ICompletionProposal;
	import org.eclipse.jface.text.contentassist.IContentAssistProcessor;
	import org.eclipse.jface.text.contentassist.IContentAssistant;
	import org.eclipse.jface.text.contentassist.IContextInformation;
	import org.eclipse.jface.text.contentassist.IContextInformationValidator;
	import org.eclipse.jface.text.source.ISourceViewer;
	import org.eclipse.jface.text.source.SourceViewer;
	import org.eclipse.jface.text.source.SourceViewerConfiguration;
	import org.eclipse.jface.viewers.ISelectionChangedListener;
	import org.eclipse.jface.viewers.SelectionChangedEvent;
	import org.eclipse.swt.SWT;
	import org.eclipse.swt.accessibility.ACC;
	import org.eclipse.swt.accessibility.AccessibleAdapter;
	import org.eclipse.swt.accessibility.AccessibleEvent;
	import org.eclipse.swt.custom.StyledText;
	import org.eclipse.swt.custom.VerifyKeyListener;
	import org.eclipse.swt.events.ModifyEvent;
	import org.eclipse.swt.events.ModifyListener;
	import org.eclipse.swt.events.SelectionAdapter;
	import org.eclipse.swt.events.SelectionEvent;
	import org.eclipse.swt.events.SelectionListener;
	import org.eclipse.swt.events.VerifyEvent;
	import org.eclipse.swt.events.VerifyListener;
	import org.eclipse.swt.graphics.Image;
	import org.eclipse.swt.graphics.Point;
	import org.eclipse.swt.layout.GridData;
	import org.eclipse.swt.layout.GridLayout;
	import org.eclipse.swt.widgets.Button;
	import org.eclipse.swt.widgets.Composite;
	import org.eclipse.swt.widgets.Control;
	import org.eclipse.swt.widgets.Label;
	import org.eclipse.ui.PlatformUI;
	import org.eclipse.wst.common.snippets.core.ISnippetItem;
	import org.eclipse.wst.common.snippets.core.ISnippetVariable;
	import org.eclipse.wst.common.snippets.internal.IHelpContextIds;
	import org.eclipse.wst.common.snippets.internal.Logger;
	import org.eclipse.wst.common.snippets.internal.SnippetsMessages;
	import org.eclipse.wst.common.snippets.internal.palette.SnippetPaletteItem;
	import org.eclipse.wst.common.snippets.internal.palette.SnippetVariable;
	import org.eclipse.wst.common.snippets.internal.ui.StringPropertyTableViewer;
	import org.eclipse.wst.common.snippets.internal.ui.ValueChangedListener;
	import org.eclipse.wst.common.snippets.internal.util.Sorter;
	import org.eclipse.wst.common.snippets.internal.util.StringUtils;

	/**
	* A snippet item editor that can define snippet variables
	*/
	public class VariableItemEditor implements ISnippetEditor {
	private static class CompletionProposalSorter extends Sorter {
	Collator collator = Collator.getInstance();

	public boolean compare(Object elementOne, Object elementTwo) {
	/**
	* Returns true if elementTwo is 'greater than' elementOne This is
	* the 'ordering' method of the sort operation. Each subclass
	* overides this method with the particular implementation of the
	* 'greater than' concept for the objects being sorted.
	*/
	ICompletionProposal proposal1 = (ICompletionProposal) elementOne;
	ICompletionProposal proposal2 = (ICompletionProposal) elementTwo;
	return (collator.compare(proposal1.getDisplayString(), proposal2.getDisplayString())) < 0;
	}
	}

	private class ItemEditorSourceViewerConfiguration extends SourceViewerConfiguration {
	private IContentAssistProcessor fProcessor = null;

	public ItemEditorSourceViewerConfiguration() {
	super();
	fProcessor = new IContentAssistProcessor() {
	char[] autochars = new char[]{};

	public ICompletionProposal[] computeCompletionProposals(ITextViewer viewer, int documentOffset) {
	java.util.List vars = new ArrayList();
	final ITextViewer textViewer = viewer;
	Iterator keys = fTableViewer.getColumnData()[0].keySet().iterator();
	while (keys.hasNext()) {
	Object key = keys.next();
	final String varID = (String) fTableViewer.getColumnData()[0].get(key);
	if (varID != null) {
	ICompletionProposal p = new ICompletionProposal() {
	protected int fReplacementOffset = textViewer.getSelectedRange().x;
	protected String varname = varID;

	public void apply(IDocument document) {
	try {
	document.replace(textViewer.getSelectedRange().x, 0, "${" + getDisplayString() + "}"); //$NON-NLS-1$ //$NON-NLS-2$
	}
	catch (BadLocationException e) {
	Logger.logException(e);
	}
	}

	public String getAdditionalProposalInfo() {
	return null;
	}

	public IContextInformation getContextInformation() {
	return null;
	}

	public String getDisplayString() {
	String display = varname;
	if (display == null)
	display = ""; //$NON-NLS-1$
	return display;
	}

	public Image getImage() {
	return null;
	}

	public Point getSelection(IDocument document) {
	return new Point(fReplacementOffset + 3 + getDisplayString().length(), 0);
	}
	};
	vars.add(p);
	}
	}
	ICompletionProposal[] proposals = new ICompletionProposal[vars.size()];
	vars.toArray(proposals);
	return sortProposals(proposals);
	}

	public IContextInformation[] computeContextInformation(ITextViewer viewer, int documentOffset) {
	return null;
	}

	public char[] getCompletionProposalAutoActivationCharacters() {
	return autochars;
	}

	public char[] getContextInformationAutoActivationCharacters() {
	return null;
	}

	public IContextInformationValidator getContextInformationValidator() {
	return null;
	}

	public String getErrorMessage() {
	return null;
	}

	public ICompletionProposal[] sortProposals(ICompletionProposal[] proposals) {
	if (proposals == null \|\| proposals.length == 0)
	return proposals;
	Object sortedProposals[] = new CompletionProposalSorter().sort(proposals);
	List sortedList = new ArrayList();
	for (int i = 0; i < sortedProposals.length; i++)
	sortedList.add(sortedProposals[i]);
	ICompletionProposal[] results = new ICompletionProposal[sortedProposals.length];
	sortedList.toArray(results);
	return results;
	}
	};
	}

	/*
	* @see SourceViewerConfiguration#getContentAssistant(ISourceViewer)
	*/
	public IContentAssistant getContentAssistant(ISourceViewer sourceViewer) {
	ContentAssistant assistant = new ContentAssistant();
	assistant.setContentAssistProcessor(fProcessor, IDocument.DEFAULT_CONTENT_TYPE);

	assistant.enableAutoActivation(false);
	assistant.setAutoActivationDelay(500);
	assistant.setProposalPopupOrientation(IContentAssistant.PROPOSAL_OVERLAY);
	assistant.setContextInformationPopupOrientation(IContentAssistant.CONTEXT_INFO_ABOVE);

	// Color background= something;
	// assistant.setContextInformationPopupBackground(background);
	// assistant.setContextSelectorBackground(background);
	// assistant.setProposalSelectorBackground(background);

	return assistant;
	}
	}

	protected StyledText content = null;
	protected SnippetPaletteItem fItem = null;
	protected StringPropertyTableViewer fTableViewer = null;
	private ModifyListener modifyListener = null;

	protected java.util.List modifyListeners = null;

	public VariableItemEditor() {
	super();
	}

	public void addModifyListener(ModifyListener listener) {
	getListeners().add(listener);
	}

	public Control createContents(Composite parent) {
	// create the contents of the variable editing dialog

	// the container for the variables fTableViewer and new/remove buttons
	PlatformUI.getWorkbench().getHelpSystem().setHelp(parent, IHelpContextIds.DIALOG_EDIT_VARITEM);

	Composite variableComposite = new Composite(parent, SWT.NONE);
	variableComposite.setLayoutData(new GridData(GridData.FILL_HORIZONTAL));
	((GridData) variableComposite.getLayoutData()).widthHint = parent.getDisplay().getClientArea().width / 3;
	GridLayout sublayout = new GridLayout();
	sublayout.numColumns = 2;
	sublayout.marginWidth = 0;
	sublayout.makeColumnsEqualWidth = false;
	variableComposite.setLayout(sublayout);

	Label nameLabel = new Label(variableComposite, SWT.NONE);
	nameLabel.setText(SnippetsMessages.Variables__4); //$NON-NLS-1$
	GridData doubleData = new GridData(GridData.FILL_HORIZONTAL);
	nameLabel.setLayoutData(doubleData);

	Label throwAway = new Label(variableComposite, SWT.NONE);
	throwAway.setLayoutData(new GridData());

	// saved and made final here to update the template text area below
	final String nameProperty = SnippetsMessages.Name_5; //$NON-NLS-1$
	fTableViewer = new StringPropertyTableViewer();
	fTableViewer.setColumnNames(new String[]{nameProperty, SnippetsMessages.Description_6, SnippetsMessages.Default_Value_7}); //$NON-NLS-1$ //$NON-NLS-2$
	fTableViewer.createContents(variableComposite);

	GridData data = new GridData(GridData.FILL_HORIZONTAL \| GridData.GRAB_HORIZONTAL);
	data.heightHint = fTableViewer.getTable().getItemHeight() * 6;
	fTableViewer.getControl().setLayoutData(data);

	// For now, each column gets its data from a separate hashtable. In
	// each,
	// the key is the ID of the variable with the values being the name,
	// description, and default value.
	ISnippetVariable[] variables = fItem.getVariables();
	for (int i = 0; i < variables.length; i++) {
	SnippetVariable var = (SnippetVariable) variables[i];
	fTableViewer.getColumnData()[0].put(var.getId(), var.getName());
	if (var.getDescription() != null)
	fTableViewer.getColumnData()[1].put(var.getId(), var.getDescription());
	else
	fTableViewer.getColumnData()[1].put(var.getId(), ""); //$NON-NLS-1$
	if (var.getDefaultValue() != null)
	fTableViewer.getColumnData()[2].put(var.getId(), var.getDefaultValue());
	else
	fTableViewer.getColumnData()[2].put(var.getId(), ""); //$NON-NLS-1$
	}
	fTableViewer.refresh();

	Composite variableButtons = new Composite(variableComposite, SWT.NULL);
	variableButtons.setLayoutData(new GridData(GridData.VERTICAL_ALIGN_BEGINNING \| GridData.HORIZONTAL_ALIGN_END));
	variableButtons.setLayout(new GridLayout());

	// Add the New button with a listener to add a new variable without
	// user
	// input.
	// TODO: for usability, throw up a dialog in the middle
	Button addButton = new Button(variableButtons, SWT.PUSH);
	addButton.setText(SnippetsMessages.New_1); //$NON-NLS-1$
	addButton.setLayoutData(new GridData(GridData.FILL_HORIZONTAL));
	addButton.addSelectionListener(new SelectionListener() {
	public void widgetDefaultSelected(SelectionEvent e) {
	widgetSelected(e);
	}

	public void widgetSelected(SelectionEvent e) {
	int i = 1;
	String newId = "name_" + i++; //$NON-NLS-1$
	while (fTableViewer.getColumnData()[0].keySet().contains(newId)) {
	newId = "name_" + i++; //$NON-NLS-1$
	}
	fTableViewer.getColumnData()[0].put(newId, newId);
	fTableViewer.getColumnData()[1].put(newId, ""); //$NON-NLS-1$
	fTableViewer.getColumnData()[2].put(newId, ""); //$NON-NLS-1$
	fTableViewer.refresh();
	}
	});
	// add the Remove button with a listener to enable it only when a
	// cell is selected and in focus
	final Button removeButton = new Button(variableButtons, SWT.PUSH);
	removeButton.setText(SnippetsMessages.Remove_15); //$NON-NLS-1$
	removeButton.setLayoutData(new GridData(GridData.FILL_HORIZONTAL));

	nameLabel = new Label(parent, SWT.NONE);
	nameLabel.setText(SnippetsMessages.Template_Pattern__16); //$NON-NLS-1$
	nameLabel.setLayoutData(new GridData(GridData.FILL_HORIZONTAL));

	// create a source viewer for to edit the text (makes it easier to
	// hook into content assist)
	final SourceViewer sourceViewer = new SourceViewer(parent, null, SWT.BORDER \| SWT.V_SCROLL \| SWT.H_SCROLL);
	sourceViewer.setEditable(true);

	// Update EOLs bug 80231
	String systemEOL = System.getProperty("line.separator"); //$NON-NLS-1$
	String text = StringUtils.replace(fItem.getContentString(), "\r\n", "\n"); //$NON-NLS-1$ //$NON-NLS-2$
	text = StringUtils.replace(text, "\r", "\n"); //$NON-NLS-1$ //$NON-NLS-2$
	if (!"\n".equals(systemEOL) && systemEOL != null) { //$NON-NLS-1$
	text = StringUtils.replace(text, "\n", systemEOL); //$NON-NLS-1$
	}
	sourceViewer.setDocument(new Document(text));

	final SourceViewerConfiguration sourceViewerConfiguration = new ItemEditorSourceViewerConfiguration();
	sourceViewer.configure(sourceViewerConfiguration);
	content = sourceViewer.getTextWidget();
	content.addModifyListener(getModifyListener());

	// add a listener to the Remove button to remove the variable
	// corresponding to the selected row
	removeButton.addSelectionListener(new SelectionListener() {
	public void widgetDefaultSelected(SelectionEvent e) {
	widgetSelected(e);
	}

	public void widgetSelected(SelectionEvent e) {
	Object id = fTableViewer.getSelection();
	if (id == null)
	return;
	// remove from template as well
	Object varKey = fTableViewer.getColumnData()[0].get(id);
	String template = sourceViewer.getDocument().get();
	sourceViewer.getDocument().set(StringUtils.replace(template, "${" + varKey + "}", "")); //$NON-NLS-1$ //$NON-NLS-2$ //$NON-NLS-3$
	fTableViewer.getColumnData()[0].remove(id);
	fTableViewer.getColumnData()[1].remove(id);
	fTableViewer.getColumnData()[2].remove(id);

	// #222898, clear selection so that SWT errors are avoided
	fTableViewer.getTable().setSelection(new int[0]);

	fTableViewer.refresh();
	removeButton.setEnabled(false);
	}
	});

	GridData contentData = new GridData(GridData.FILL_BOTH);
	contentData.heightHint = parent.getDisplay().getClientArea().height / 5;
	content.setLayoutData(contentData);
	content.setFont(org.eclipse.jface.resource.JFaceResources.getTextFont());
	content.setHorizontalPixel(2);
	// add a verify key listener to trigger the source viewer's undo
	// action
	content.addVerifyKeyListener(new VerifyKeyListener() {
	public void verifyKey(VerifyEvent event) {
	if (!event.doit)
	return;
	boolean doContentAssistOperation = (event.stateMask == SWT.CTRL && event.character == ' ');
	if (doContentAssistOperation) {
	sourceViewer.doOperation(ISourceViewer.CONTENTASSIST_PROPOSALS);
	event.doit = false;
	}
	// CTRL-Z (derived from the JDT template editor's way of
	// assigning the event.character)
	else if (event.stateMask == SWT.CTRL && (event.character == ('z' - 'a' + 1))) {
	sourceViewer.doOperation(ITextOperationTarget.UNDO);
	event.doit = false;
	}
	}
	});
	// add a verify listener to trigger the source viewer's content assist
	// and undo actions
	// TODO: determine if this is duplicated effort
	content.addVerifyListener(new VerifyListener() {
	public void verifyText(VerifyEvent event) {
	if (!event.doit \|\| !((event.stateMask & SWT.CTRL) == 1))
	return;
	boolean doContentAssistOperation = (event.stateMask == SWT.CTRL && event.character == ' ');
	// prevent inserting a space character when content assist is
	// invoked
	if (doContentAssistOperation) {
	event.doit = false;
	}
	// CTRL-Z
	else if (event.stateMask == SWT.CTRL && event.character == ('z' - 'a' + 1)) {
	event.doit = false;
	}
	}
	});

	// specifically associate the template pattern label w/ the content
	// styled text so screen reader reads it
	setAccessible(content, SnippetsMessages.Template_Pattern__16); //$NON-NLS-1$

	// add a value change listener to the fTableViewer so that changes to
	// the name property of a variable
	// will rewrite the template text to use the new name immediately
	// TODO: verify with the user that this is OK with them
	fTableViewer.addValueChangedListener(new ValueChangedListener() {
	public void valueChanged(String key, String property, String oldValue, String newValue) {
	if (property.equals(nameProperty)) {
	String newText = StringUtils.replace(content.getText(), "${" + oldValue + "}", "${" + newValue + "}"); //$NON-NLS-1$ //$NON-NLS-2$ //$NON-NLS-3$ //$NON-NLS-4$
	content.setText(newText);
	}
	}
	});

	/*
	* Add the "Insert Variable Placeholder" button to invoke content
	* assist like the JDT Template editor.
	*
	* I'm not sure I like this idea as it's mostly a crutch for not
	* making content assist obviously available in the source viewer.
	*/
	final Button insertVariableButton = new Button(parent, SWT.PUSH);
	insertVariableButton.setText(SnippetsMessages.Insert_Variable_17); //$NON-NLS-1$
	insertVariableButton.setLayoutData(new GridData(GridData.HORIZONTAL_ALIGN_BEGINNING \| GridData.VERTICAL_ALIGN_BEGINNING));
	insertVariableButton.setEnabled(fTableViewer.getTable().getItemCount() > 0);
	insertVariableButton.addSelectionListener(new SelectionListener() {
	public void widgetDefaultSelected(SelectionEvent e) {
	widgetSelected(e);
	}

	public void widgetSelected(SelectionEvent e) {
	// JDT template editor invokes Content Assist on a
	// configured Java Source Viewer. Not that simple here.
	sourceViewer.getTextWidget().setFocus();
	sourceViewer.doOperation(ISourceViewer.CONTENTASSIST_PROPOSALS);
	}
	});

	fTableViewer.addSelectionChangedListener(new ISelectionChangedListener() {
	public void selectionChanged(SelectionChangedEvent event) {
	insertVariableButton.setEnabled(fTableViewer.getTable().getItemCount() > 0);
	removeButton.setEnabled(fTableViewer.getControl().isFocusControl() && event.getSelection() != null && (!event.getSelection().isEmpty()));
	}
	});

	addButton.addSelectionListener(new SelectionAdapter() {
	public void widgetSelected(SelectionEvent e) {
	insertVariableButton.setEnabled(true);
	}
	});
	removeButton.addSelectionListener(new SelectionAdapter() {
	public void widgetDefaultSelected(SelectionEvent e) {
	insertVariableButton.setEnabled(fTableViewer.getTable().getItemCount() > 0);
	}

	public void widgetSelected(SelectionEvent e) {
	insertVariableButton.setEnabled(fTableViewer.getTable().getItemCount() > 0);
	}
	});
	// set the initial enabled state
	removeButton.setEnabled(false);

	return parent;
	}

	protected void fireModification(ModifyEvent e) {
	Iterator i = getListeners().iterator();
	updateItem();
	while (i.hasNext())
	((ModifyListener) (i.next())).modifyText(e);
	}

	public ISnippetItem getItem() {
	return fItem;
	}

	private java.util.List getListeners() {
	if (modifyListeners == null)
	modifyListeners = new ArrayList();
	return modifyListeners;
	}

	protected ModifyListener getModifyListener() {
	if (modifyListener == null) {
	modifyListener = new ModifyListener() {
	public void modifyText(ModifyEvent e) {
	fireModification(e);
	}
	};
	}
	return modifyListener;
	}

	public void removeModifyListener(ModifyListener listener) {
	getListeners().remove(listener);
	}

	/**
	* Specifically set the reporting name of a control for accessibility
	*/
	private void setAccessible(Control control, String name) {
	if (control == null)
	return;
	final String n = name;
	control.getAccessible().addAccessibleListener(new AccessibleAdapter() {
	public void getName(AccessibleEvent e) {
	if (e.childID == ACC.CHILDID_SELF)
	e.result = n;
	}
	});
	}

	public void setItem(SnippetPaletteItem item) {
	fItem = item;
	}

	public void updateItem() {
	String text = content.getText();
	// Update related to bug 80231
	text = StringUtils.replace(text, "\r\n", "\n"); //$NON-NLS-1$ //$NON-NLS-2$
	text = StringUtils.replace(text, "\r", "\n"); //$NON-NLS-1$ //$NON-NLS-2$
	fItem.setContentString(text);

	ISnippetVariable[] variables = fItem.getVariables();
	for (int i = 0; i < variables.length; i++) {
	fItem.removeVariable(variables[i]);
	}
	Iterator ids = fTableViewer.getColumnData()[0].keySet().iterator();
	while (ids.hasNext()) {
	Object key = ids.next();
	SnippetVariable var = new SnippetVariable();
	var.setId((String) key);
	var.setName((String) fTableViewer.getColumnData()[0].get(key));
	var.setDescription((String) fTableViewer.getColumnData()[1].get(key));
	var.setDefaultValue((String) fTableViewer.getColumnData()[2].get(key));
	fItem.addVariable(var);
	}
	}
	}