net.sourceforge.phpeclipse/src/net/sourceforge/phpdt/internal/ui/text/template/contentassist/TemplateEngine.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.phpdt.internal.ui.text.template.contentassist;
  12
  13 import java.util.ArrayList;
  14
  15 import net.sourceforge.phpdt.core.ICompilationUnit;
  16 import net.sourceforge.phpdt.internal.corext.Assert;
  17 import net.sourceforge.phpdt.internal.corext.template.php.CompilationUnitContext;
  18 import net.sourceforge.phpdt.internal.corext.template.php.CompilationUnitContextType;
  19 import net.sourceforge.phpdt.internal.ui.PHPUiImages;
  20 import net.sourceforge.phpeclipse.PHPeclipsePlugin;
  21
  22 import org.eclipse.jface.text.BadLocationException;
  23 import org.eclipse.jface.text.IDocument;
  24 import org.eclipse.jface.text.IRegion;
  25 import org.eclipse.jface.text.ITextViewer;
  26 import org.eclipse.jface.text.Region;
  27 import org.eclipse.jface.text.templates.GlobalTemplateVariables;
  28 import org.eclipse.jface.text.templates.Template;
  29 import org.eclipse.jface.text.templates.TemplateContextType;
  30 import org.eclipse.swt.graphics.Point;
  31
  32 public class TemplateEngine {
  33
  34         private static final String $_LINE_SELECTION = "${" + GlobalTemplateVariables.LineSelection.NAME + "}"; //$NON-NLS-1$ //$NON-NLS-2$
  35
  36         private static final String $_WORD_SELECTION = "${" + GlobalTemplateVariables.WordSelection.NAME + "}"; //$NON-NLS-1$ //$NON-NLS-2$
  37
  38         /** The context type. */
  39         private TemplateContextType fContextType;
  40
  41         /** The result proposals. */
  42         private ArrayList fProposals = new ArrayList();
  43
  44         /**
  45          * Creates the template engine for a particular context type. See
  46          * <code>TemplateContext</code> for supported context types.
  47          */
  48         public TemplateEngine(TemplateContextType contextType) {
  49                 Assert.isNotNull(contextType);
  50                 fContextType = contextType;
  51         }
  52
  53         /**
  54          * Empties the collector.
  55          */
  56         public void reset() {
  57                 fProposals.clear();
  58         }
  59
  60         /**
  61          * Returns the array of matching templates.
  62          */
  63         public TemplateProposal[] getResults() {
  64                 return (TemplateProposal[]) fProposals
  65                                 .toArray(new TemplateProposal[fProposals.size()]);
  66         }
  67
  68         /**
  69          * Inspects the context of the compilation unit around
  70          * <code>completionPosition</code> and feeds the collector with proposals.
  71          *
  72          * @param viewer
  73          *            the text viewer
  74          * @param completionPosition
  75          *            the context position in the document of the text viewer
  76          * @param compilationUnit
  77          *            the compilation unit (may be <code>null</code>)
  78          */
  79         public void complete(ITextViewer viewer, int completionPosition,
  80                         ICompilationUnit compilationUnit) {
  81                 IDocument document = viewer.getDocument();
  82
  83                 if (!(fContextType instanceof CompilationUnitContextType))
  84                         return;
  85
  86                 Point selection = viewer.getSelectedRange();
  87
  88                 // remember selected text
  89                 String selectedText = null;
  90                 if (selection.y != 0) {
  91                         try {
  92                                 selectedText = document.get(selection.x, selection.y);
  93                         } catch (BadLocationException e) {
  94                         }
  95                 }
  96
  97                 CompilationUnitContext context = ((CompilationUnitContextType) fContextType)
  98                                 .createContext(document, completionPosition, selection.y,
  99                                                 compilationUnit);
 100                 context.setVariable("selection", selectedText); //$NON-NLS-1$
 101                 int start = context.getStart();
 102                 int end = context.getEnd();
 103                 IRegion region = new Region(start, end - start);
 104
 105                 Template[] templates = PHPeclipsePlugin.getDefault().getTemplateStore()
 106                                 .getTemplates();
 107
 108                 if (selection.y == 0) {
 109                         for (int i = 0; i != templates.length; i++)
 110                                 if (context.canEvaluate(templates[i]))
 111                                         fProposals.add(new TemplateProposal(templates[i], context,
 112                                                         region, PHPUiImages
 113                                                                         .get(PHPUiImages.IMG_OBJS_TEMPLATE)));
 114
 115                 } else {
 116
 117                         if (context.getKey().length() == 0)
 118                                 context.setForceEvaluation(true);
 119
 120                         boolean multipleLinesSelected = areMultipleLinesSelected(viewer);
 121
 122                         for (int i = 0; i != templates.length; i++) {
 123                                 Template template = templates[i];
 124                                 if (context.canEvaluate(template)
 125                                                 && template.getContextTypeId().equals(
 126                                                                 context.getContextType().getId())
 127                                                 && (!multipleLinesSelected
 128                                                                 && template.getPattern().indexOf(
 129                                                                                 $_WORD_SELECTION) != -1 || (multipleLinesSelected && template
 130                                                                 .getPattern().indexOf($_LINE_SELECTION) != -1))) {
 131                                         fProposals.add(new TemplateProposal(templates[i], context,
 132                                                         region, PHPUiImages
 133                                                                         .get(PHPUiImages.IMG_OBJS_TEMPLATE)));
 134                                 }
 135                         }
 136                 }
 137         }
 138
 139         /**
 140          * Returns <code>true</code> if one line is completely selected or if
 141          * multiple lines are selected. Being completely selected means that all
 142          * characters except the new line characters are selected.
 143          *
 144          * @return <code>true</code> if one or multiple lines are selected
 145          * @since 2.1
 146          */
 147         private boolean areMultipleLinesSelected(ITextViewer viewer) {
 148                 if (viewer == null)
 149                         return false;
 150
 151                 Point s = viewer.getSelectedRange();
 152                 if (s.y == 0)
 153                         return false;
 154
 155                 try {
 156
 157                         IDocument document = viewer.getDocument();
 158                         int startLine = document.getLineOfOffset(s.x);
 159                         int endLine = document.getLineOfOffset(s.x + s.y);
 160                         IRegion line = document.getLineInformation(startLine);
 161                         return startLine != endLine
 162                                         || (s.x == line.getOffset() && s.y == line.getLength());
 163
 164                 } catch (BadLocationException x) {
 165                         return false;
 166                 }
 167         }
 168 }