net.sourceforge.phpeclipse.ui/src/net/sourceforge/phpeclipse/ui/templates/template/BasicCompletionProcessor.java

   1 /*******************************************************************************
   2  * Copyright (c) 2000, 2004 IBM Corporation and others.
   3  * All rights reserved. This program and the accompanying materials
   4  * are made available under the terms of the Common Public License v1.0
   5  * which accompanies this distribution, and is available at
   6  * http://www.eclipse.org/legal/cpl-v10.html
   7  *
   8  * Contributors:
   9  *     IBM Corporation - initial API and implementation
  10  *******************************************************************************/
  11 package net.sourceforge.phpeclipse.ui.templates.template;
  12
  13 import java.util.ArrayList;
  14 import java.util.List;
  15
  16 import net.sourceforge.phpeclipse.ui.WebUI;
  17
  18 import org.eclipse.jface.resource.ImageDescriptor;
  19 import org.eclipse.jface.resource.ImageRegistry;
  20 import org.eclipse.jface.text.BadLocationException;
  21 import org.eclipse.jface.text.IDocument;
  22 import org.eclipse.jface.text.IRegion;
  23 import org.eclipse.jface.text.ITextSelection;
  24 import org.eclipse.jface.text.ITextViewer;
  25 import org.eclipse.jface.text.Region;
  26 import org.eclipse.jface.text.contentassist.ICompletionProposal;
  27 import org.eclipse.jface.text.contentassist.IContentAssistProcessor;
  28 import org.eclipse.jface.text.templates.Template;
  29 import org.eclipse.jface.text.templates.TemplateCompletionProcessor;
  30 import org.eclipse.jface.text.templates.TemplateContext;
  31 import org.eclipse.jface.text.templates.TemplateContextType;
  32 import org.eclipse.jface.text.templates.TemplateException;
  33 import org.eclipse.swt.graphics.Image;
  34
  35 /**
  36  * A completion processor for XML templates.
  37  */
  38 public class BasicCompletionProcessor extends TemplateCompletionProcessor {
  39         private static final String DEFAULT_IMAGE = "icons/template.gif"; //$NON-NLS-1$
  40
  41         private char[] fProposalAutoActivationSet;
  42
  43         // private PHPCompletionProposalComparator fComparator;
  44         public BasicCompletionProcessor() {
  45                 super();
  46                 // fComparator = new PHPCompletionProposalComparator();
  47         }
  48
  49         /**
  50          * We watch for angular brackets since those are often part of XML
  51          * templates.
  52          */
  53         protected String extractPrefix(ITextViewer viewer, int offset) {
  54                 IDocument document = viewer.getDocument();
  55                 int i = offset;
  56                 if (i > document.getLength())
  57                         return ""; //$NON-NLS-1$
  58
  59                 try {
  60                         while (i > 0) {
  61                                 char ch = document.getChar(i - 1);
  62                                 if (ch != '<' && ch != '&' && ch != '{'
  63                                                 && !Character.isJavaIdentifierPart(ch))
  64                                         break;
  65                                 i--;
  66                         }
  67
  68                         return document.get(i, offset - i);
  69                 } catch (BadLocationException e) {
  70                         return ""; //$NON-NLS-1$
  71                 }
  72         }
  73
  74         /**
  75          * Cut out angular brackets for relevance sorting, since the template name
  76          * does not contain the brackets.
  77          */
  78         protected int getRelevance(Template template, String prefix) {
  79                 // if (prefix.startsWith("<")) //$NON-NLS-1$
  80                 // prefix= prefix.substring(1);
  81                 if (template.getName().startsWith(prefix))
  82                         return 90;
  83                 return 0;
  84         }
  85
  86         /**
  87          * Simply return all templates.
  88          */
  89         protected Template[] getTemplates(String contextTypeId) {
  90                 return WebUI.getDefault().getTemplateStore().getTemplates();
  91         }
  92
  93         /**
  94          * Return the XML context type that is supported by this plugin.
  95          */
  96         protected TemplateContextType getContextType(ITextViewer viewer,
  97                         IRegion region) {
  98                 return WebUI.getDefault().getContextTypeRegistry().getContextType(
  99                                 XMLContextType.XML_CONTEXT_TYPE);
 100         }
 101
 102         /**
 103          * Always return the default image.
 104          */
 105         protected Image getImage(Template template) {
 106                 ImageRegistry registry = WebUI.getDefault().getImageRegistry();
 107                 Image image = registry.get(DEFAULT_IMAGE);
 108                 if (image == null) {
 109                         ImageDescriptor desc = WebUI.imageDescriptorFromPlugin(
 110                                         "org.eclipse.ui.examples.javaeditor", DEFAULT_IMAGE); //$NON-NLS-1$
 111                         registry.put(DEFAULT_IMAGE, desc);
 112                         image = registry.get(DEFAULT_IMAGE);
 113                 }
 114                 return image;
 115         }
 116
 117         /*
 118          * (non-Javadoc)
 119          *
 120          * @see org.eclipse.jface.text.contentassist.IContentAssistProcessor#computeCompletionProposals(org.eclipse.jface.text.ITextViewer,
 121          *      int)
 122          */
 123         public ICompletionProposal[] computeCompletionProposals(ITextViewer viewer,
 124                         int offset) {
 125                 ITextSelection selection = (ITextSelection) viewer
 126                                 .getSelectionProvider().getSelection();
 127
 128                 // adjust offset to end of normalized selection
 129                 if (selection.getOffset() == offset)
 130                         offset = selection.getOffset() + selection.getLength();
 131
 132                 String prefix = extractPrefix(viewer, offset);
 133                 prefix = prefix.toLowerCase();
 134                 IRegion region = new Region(offset - prefix.length(), prefix.length());
 135                 TemplateContext context = createContext(viewer, region);
 136                 if (context == null)
 137                         return new ICompletionProposal[0];
 138
 139                 context.setVariable("selection", selection.getText()); // name of the
 140                                                                                                                                 // selection
 141                                                                                                                                 // variables
 142                                                                                                                                 // {line,
 143                                                                                                                                 // word}_selection
 144                                                                                                                                 // //$NON-NLS-1$
 145
 146                 Template[] templates = getTemplates(context.getContextType().getId());
 147
 148                 List matches = new ArrayList();
 149                 for (int i = 0; i < templates.length; i++) {
 150                         Template template = templates[i];
 151                         try {
 152                                 context.getContextType().validate(template.getPattern());
 153                         } catch (TemplateException e) {
 154                                 continue;
 155                         }
 156
 157                         if (template.getName().startsWith(prefix)) { // &&
 158                                                                                                                         // template.matches(prefix,
 159                                                                                                                         // context.getContextType().getId()))
 160                                 matches.add(createProposal(template, context, region,
 161                                                 getRelevance(template, prefix)));
 162                         }
 163                 }
 164
 165                 return (ICompletionProposal[]) matches
 166                                 .toArray(new ICompletionProposal[matches.size()]);
 167
 168         }
 169
 170         /**
 171          * @see IContentAssistProcessor#getCompletionProposalAutoActivationCharacters()
 172          */
 173         public char[] getCompletionProposalAutoActivationCharacters() {
 174                 return fProposalAutoActivationSet;
 175         }
 176
 177         /**
 178          * Sets this processor's set of characters triggering the activation of the
 179          * completion proposal computation.
 180          *
 181          * @param activationSet
 182          *            the activation set
 183          */
 184         public void setCompletionProposalAutoActivationCharacters(
 185                         char[] activationSet) {
 186                 fProposalAutoActivationSet = activationSet;
 187         }
 188
 189         /**
 190          * Order the given proposals.
 191          */
 192         // private ICompletionProposal[] order(ICompletionProposal[] proposals) {
 193         // Arrays.sort(proposals, fComparator);
 194         // return proposals;
 195         // }
 196         /**
 197          * Tells this processor to order the proposals alphabetically.
 198          *
 199          * @param order
 200          *            <code>true</code> if proposals should be ordered.
 201          */
 202         // public void orderProposalsAlphabetically(boolean order) {
 203         // fComparator.setOrderAlphabetically(order);
 204         // }
 205 }