Bug 485028: Toggle Comments for Makefile Editor

Change-Id: I40b6daca54aa17022971df0749d1c4d7708a6564
Signed-off-by: Andrew Gvozdev <angvoz.dev@gmail.com>

5 files changed, 377 insertions, 14 deletions

diff --git a/build/org.eclipse.cdt.make.ui/src/org/eclipse/cdt/make/internal/ui/editor/IMakefileEditorActionDefinitionIds.java b/build/org.eclipse.cdt.make.ui/src/org/eclipse/cdt/make/internal/ui/editor/IMakefileEditorActionDefinitionIds.java
index a778755e799..e3e47b533fb 100644
--- a/build/org.eclipse.cdt.make.ui/src/org/eclipse/cdt/make/internal/ui/editor/IMakefileEditorActionDefinitionIds.java
+++ b/build/org.eclipse.cdt.make.ui/src/org/eclipse/cdt/make/internal/ui/editor/IMakefileEditorActionDefinitionIds.java
@@ -11,12 +11,10 @@
 
 package org.eclipse.cdt.make.internal.ui.editor;
 
-import org.eclipse.ui.texteditor.ITextEditorActionDefinitionIds;
-
 /**
+ * Custom definitions IDs extending ITextEditorActionDefinitionIds
  */
-public interface IMakefileEditorActionDefinitionIds extends ITextEditorActionDefinitionIds {
-	final String UNCOMMENT = "org.eclipse.cdt.make.ui.edit.text.makefile.uncomment"; //$NON-NLS-1$
-	final String COMMENT = "org.eclipse.cdt.make.ui.edit.text.makefile.comment"; //$NON-NLS-1$
+public interface IMakefileEditorActionDefinitionIds {
+	final String TOGGLE_COMMENT = "org.eclipse.cdt.make.ui.edit.text.makefile.toggle.comment"; //$NON-NLS-1$
 	final String OPEN_DECLARATION = "org.eclipse.cdt.make.ui.edit.text.makefile.opendecl"; //$NON-NLS-1$
 }
diff --git a/build/org.eclipse.cdt.make.ui/src/org/eclipse/cdt/make/internal/ui/editor/MakefileEditor.java b/build/org.eclipse.cdt.make.ui/src/org/eclipse/cdt/make/internal/ui/editor/MakefileEditor.java
index 11be9d797df..183f5cf6d59 100644
--- a/build/org.eclipse.cdt.make.ui/src/org/eclipse/cdt/make/internal/ui/editor/MakefileEditor.java
+++ b/build/org.eclipse.cdt.make.ui/src/org/eclipse/cdt/make/internal/ui/editor/MakefileEditor.java
@@ -32,7 +32,6 @@ import org.eclipse.jface.text.BadLocationException;
 import org.eclipse.jface.text.FindReplaceDocumentAdapter;
 import org.eclipse.jface.text.IDocument;
 import org.eclipse.jface.text.IRegion;
-import org.eclipse.jface.text.ITextOperationTarget;
 import org.eclipse.jface.text.rules.IWordDetector;
 import org.eclipse.jface.text.source.DefaultCharacterPairMatcher;
 import org.eclipse.jface.text.source.ISourceViewer;
@@ -224,15 +223,14 @@ public class MakefileEditor extends TextEditor implements ISelectionChangedListe
 		a.setActionDefinitionId(ITextEditorActionDefinitionIds.CONTENT_ASSIST_CONTEXT_INFORMATION);
 		setAction("ContentAssistTip", a); //$NON-NLS-1$
 
-		a = new TextOperationAction(bundle, "Comment.", this, ITextOperationTarget.PREFIX); //$NON-NLS-1$
-		a.setActionDefinitionId(IMakefileEditorActionDefinitionIds.COMMENT);
-		setAction("Comment", a); //$NON-NLS-1$
-		markAsStateDependentAction("Comment", true); //$NON-NLS-1$
+		a = new MakefileToggleCommentAction(bundle, "ToggleComment.", this); //$NON-NLS-1$
+		a.setActionDefinitionId(IMakefileEditorActionDefinitionIds.TOGGLE_COMMENT);
+		setAction("ToggleComment", a); //$NON-NLS-1$
+		markAsStateDependentAction("ToggleComment", true); //$NON-NLS-1$
 
-		a = new TextOperationAction(bundle, "Uncomment.", this, ITextOperationTarget.STRIP_PREFIX); //$NON-NLS-1$
-		a.setActionDefinitionId(IMakefileEditorActionDefinitionIds.UNCOMMENT);
-		setAction("Uncomment", a); //$NON-NLS-1$
-		markAsStateDependentAction("Uncomment", true); //$NON-NLS-1$
+		ISourceViewer sourceViewer = getSourceViewer();
+		SourceViewerConfiguration configuration = getSourceViewerConfiguration();
+		((MakefileToggleCommentAction) a).configure(sourceViewer, configuration);
 
 		a = new OpenDeclarationAction(this);
 		a.setActionDefinitionId(IMakefileEditorActionDefinitionIds.OPEN_DECLARATION);
diff --git a/build/org.eclipse.cdt.make.ui/src/org/eclipse/cdt/make/internal/ui/editor/MakefileEditorMessages.java b/build/org.eclipse.cdt.make.ui/src/org/eclipse/cdt/make/internal/ui/editor/MakefileEditorMessages.java
index 481b0762e34..69d22c5e00d 100644
--- a/build/org.eclipse.cdt.make.ui/src/org/eclipse/cdt/make/internal/ui/editor/MakefileEditorMessages.java
+++ b/build/org.eclipse.cdt.make.ui/src/org/eclipse/cdt/make/internal/ui/editor/MakefileEditorMessages.java
@@ -15,6 +15,8 @@ import org.eclipse.osgi.util.NLS;
 
 public final class MakefileEditorMessages extends NLS {
 	public static String MakefileEditor_menu_folding;
+	public static String ToggleComment_error_title;
+	public static String ToggleComment_error_message;
 
 	static {
 		NLS.initializeMessages(MakefileEditorMessages.class.getName(), MakefileEditorMessages.class);
diff --git a/build/org.eclipse.cdt.make.ui/src/org/eclipse/cdt/make/internal/ui/editor/MakefileEditorMessages.properties b/build/org.eclipse.cdt.make.ui/src/org/eclipse/cdt/make/internal/ui/editor/MakefileEditorMessages.properties
index b9b71ecd383..2c21e0165e2 100644
--- a/build/org.eclipse.cdt.make.ui/src/org/eclipse/cdt/make/internal/ui/editor/MakefileEditorMessages.properties
+++ b/build/org.eclipse.cdt.make.ui/src/org/eclipse/cdt/make/internal/ui/editor/MakefileEditorMessages.properties
@@ -10,3 +10,6 @@
 #########################################
 
 MakefileEditor_menu_folding=F&olding
+ToggleComment_error_title=Comment/Uncomment
+ToggleComment_error_message=An error occurred while commenting/uncommenting.
+
diff --git a/build/org.eclipse.cdt.make.ui/src/org/eclipse/cdt/make/internal/ui/editor/MakefileToggleCommentAction.java b/build/org.eclipse.cdt.make.ui/src/org/eclipse/cdt/make/internal/ui/editor/MakefileToggleCommentAction.java
new file mode 100644
index 00000000000..b98af118304
--- /dev/null
+++ b/build/org.eclipse.cdt.make.ui/src/org/eclipse/cdt/make/internal/ui/editor/MakefileToggleCommentAction.java
@@ -0,0 +1,362 @@
+/*******************************************************************************
+ * Copyright (c) 2015, 2015 Andrew Gvozdev 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:
+ *     Andrew Gvozdev - initial API and implementation based on org.eclipse.cdt.internal.ui.editor.ToggleCommentAction
+ *******************************************************************************/
+
+package org.eclipse.cdt.make.internal.ui.editor;
+
+import java.util.HashMap;
+import java.util.Map;
+import java.util.ResourceBundle;
+
+import org.eclipse.jface.dialogs.MessageDialog;
+import org.eclipse.jface.text.BadLocationException;
+import org.eclipse.jface.text.IDocument;
+import org.eclipse.jface.text.IRegion;
+import org.eclipse.jface.text.ITextOperationTarget;
+import org.eclipse.jface.text.ITextSelection;
+import org.eclipse.jface.text.ITypedRegion;
+import org.eclipse.jface.text.Region;
+import org.eclipse.jface.text.TextUtilities;
+import org.eclipse.jface.text.TextViewer;
+import org.eclipse.jface.text.source.ISourceViewer;
+import org.eclipse.jface.text.source.SourceViewerConfiguration;
+import org.eclipse.jface.viewers.ISelection;
+import org.eclipse.swt.custom.BusyIndicator;
+import org.eclipse.swt.widgets.Display;
+import org.eclipse.swt.widgets.Shell;
+import org.eclipse.ui.texteditor.ITextEditor;
+import org.eclipse.ui.texteditor.ResourceAction;
+import org.eclipse.ui.texteditor.TextEditorAction;
+import org.eclipse.cdt.make.internal.ui.MakeUIPlugin;
+
+/**
+ * An action which toggles comment prefixes on the selected lines.
+ */
+public final class MakefileToggleCommentAction extends TextEditorAction {
+	/** The text operation target */
+	private ITextOperationTarget fOperationTarget;
+	/** The document partitioning */
+	private String fDocumentPartitioning;
+	/** The comment prefixes */
+	private Map<String, String[]> fPrefixesMap;
+
+	/**
+	 * Creates and initializes the action for the given text editor. The action
+	 * configures its visual representation from the given resource bundle.
+	 *
+	 * @param bundle the resource bundle
+	 * @param prefix a prefix to be prepended to the various resource keys
+	 *   (described in <code>ResourceAction</code> constructor), or
+	 *   <code>null</code> if none
+	 * @param editor the text editor
+	 * @see ResourceAction#ResourceAction(ResourceBundle, String, int)
+	 */
+	public MakefileToggleCommentAction(ResourceBundle bundle, String prefix, ITextEditor editor) {
+		super(bundle, prefix, editor);
+	}
+
+	/**
+	 * Implementation of the <code>IAction</code> prototype. Checks if the selected
+	 * lines are all commented or not and uncomments/comments them respectively.
+	 */
+	@Override
+	public void run() {
+		if (fOperationTarget == null || fDocumentPartitioning == null || fPrefixesMap == null)
+			return;
+
+		ITextEditor editor= getTextEditor();
+		if (editor == null)
+			return;
+
+		if (!validateEditorInputState())
+			return;
+
+		final int operationCode;
+		if (isSelectionCommented(editor.getSelectionProvider().getSelection()))
+			operationCode= ITextOperationTarget.STRIP_PREFIX;
+		else
+			operationCode= ITextOperationTarget.PREFIX;
+
+		Shell shell= editor.getSite().getShell();
+		if (!fOperationTarget.canDoOperation(operationCode)) {
+			if (shell != null) {
+				MessageDialog.openError(shell, MakefileEditorMessages.ToggleComment_error_title,
+						MakefileEditorMessages.ToggleComment_error_message);
+			}
+			return;
+		}
+
+		Display display= null;
+		if (shell != null && !shell.isDisposed())
+			display= shell.getDisplay();
+
+		BusyIndicator.showWhile(display, new Runnable() {
+			@Override
+			public void run() {
+				fOperationTarget.doOperation(operationCode);
+			}
+		});
+	}
+
+	/**
+	 * Is the given selection single-line commented?
+	 *
+	 * @param selection Selection to check
+	 * @return <code>true</code> iff all selected lines are commented
+	 */
+	private boolean isSelectionCommented(ISelection selection) {
+		if (!(selection instanceof ITextSelection))
+			return false;
+
+		ITextSelection textSelection= (ITextSelection) selection;
+		if (textSelection.getStartLine() < 0 || textSelection.getEndLine() < 0)
+			return false;
+
+		IDocument document= getTextEditor().getDocumentProvider().getDocument(getTextEditor().getEditorInput());
+
+		try {
+			IRegion block= getTextBlockFromSelection(textSelection, document);
+			ITypedRegion[] regions= TextUtilities.computePartitioning(document, fDocumentPartitioning,
+					block.getOffset(), block.getLength(), false);
+
+			int[] lines= new int[regions.length * 2]; // [startline, endline, startline, endline, ...]
+
+			// For each partition in the text selection, figure out the startline and endline.
+			// Count the number of lines that are selected.
+			for (int i = 0, j = 0; i < regions.length; i++, j+= 2) {
+				// Start line of region
+				lines[j]= getFirstCompleteLineOfRegion(regions[i], document);
+				// End line of region
+				int length= regions[i].getLength();
+				int offset= regions[i].getOffset() + length;
+				if (length > 0)
+					offset--;
+
+				// If there is no startline for this region (startline = -1),
+				// then there is no endline,
+				// otherwise, get the line number of the endline and store it in the array.
+				lines[j + 1]= (lines[j] == -1 ? -1 : document.getLineOfOffset(offset));
+
+				// We could count the number of lines that are selected in this region
+				// lineCount += lines[j + 1] - lines[j] + 1;
+
+				assert i < regions.length;
+				assert j < regions.length * 2;
+			}
+
+			// Perform the check
+			boolean hasComment= false;
+			for (int i = 0, j = 0; i < regions.length; i++, j += 2) {
+				String[] prefixes= fPrefixesMap.get(regions[i].getType());
+				if (prefixes != null && prefixes.length > 0 && lines[j] >= 0 && lines[j + 1] >= 0) {
+					if (isBlockCommented(lines[j], lines[j + 1], prefixes, document)) {
+						hasComment= true;
+					} else if (!isBlockEmpty(lines[j], lines[j + 1], document)) {
+						return false;
+					}
+				}
+			}
+			return hasComment;
+		} catch (BadLocationException e) {
+			MakeUIPlugin.log(e);  // Should not happen
+		}
+
+		return false;
+	}
+
+	/**
+	 * Creates a region describing the text block (something that starts at
+	 * the beginning of a line) completely containing the current selection.
+	 *
+	 * Note, the implementation has to match {@link TextViewer}.getTextBlockFromSelection().
+	 * 
+	 * @param selection The selection to use
+	 * @param document The document
+	 * @return the region describing the text block comprising the given selection
+	 */
+	private IRegion getTextBlockFromSelection(ITextSelection selection, IDocument document) throws BadLocationException {
+		int start= document.getLineOffset(selection.getStartLine());
+		int end;
+		int endLine= selection.getEndLine();
+		if (document.getNumberOfLines() > endLine+1) {
+			end= document.getLineOffset(endLine+1);
+		} else {
+			end= document.getLength();
+		}
+		return new Region(start, end - start);
+	}
+
+	/**
+	 * Returns the index of the first line whose start offset is in the given text range.
+	 *
+	 * @param region the text range in characters where to find the line
+	 * @param document The document
+	 * @return the first line whose start index is in the given range, -1 if there is no such line
+	 */
+	private int getFirstCompleteLineOfRegion(IRegion region, IDocument document) {
+		try {
+			int startLine= document.getLineOfOffset(region.getOffset());
+
+			int offset= document.getLineOffset(startLine);
+			if (offset >= region.getOffset())
+				return startLine;
+
+			offset= document.getLineOffset(startLine + 1);
+			return (offset > region.getOffset() + region.getLength() ? -1 : startLine + 1);
+		} catch (BadLocationException e) {
+			MakeUIPlugin.log(e);  // Should not happen
+		}
+
+		return -1;
+	}
+
+	/**
+	 * Determines whether each line is prefixed by one of the prefixes.
+	 *
+	 * @param startLine Start line in document
+	 * @param endLine End line in document
+	 * @param prefixes Possible comment prefixes
+	 * @param document The document
+	 * @return <code>true</code> iff each line from <code>startLine</code>
+	 *             to and including <code>endLine</code> is prepended by one
+	 *             of the <code>prefixes</code>, ignoring whitespace at the
+	 *             begin of line
+	 */
+	private boolean isBlockCommented(int startLine, int endLine, String[] prefixes, IDocument document) {
+		try {
+			// Check for occurrences of prefixes in the given lines
+			boolean hasComment = false;
+			for (int i= startLine; i <= endLine; i++) {
+				IRegion line= document.getLineInformation(i);
+				String text= document.get(line.getOffset(), line.getLength());
+
+				boolean isEmptyLine = text.trim().length() == 0;
+				if(isEmptyLine) {
+					continue;
+				}
+				
+				int[] found= TextUtilities.indexOf(prefixes, text, 0);
+
+				if (found[0] == -1) {
+					// Found a line which is not commented
+					return false;
+				}
+				String s= document.get(line.getOffset(), found[0]);
+				s= s.trim();
+				if (s.length() != 0) {
+					// Found a line which is not commented
+					return false;
+				}
+				hasComment = true;
+			}
+			return hasComment;
+		} catch (BadLocationException e) {
+			MakeUIPlugin.log(e);  // Should not happen
+		}
+
+		return false;
+	}
+
+	/**
+	 * Determines whether each line is empty
+	 *
+	 * @param startLine Start line in document
+	 * @param endLine End line in document
+	 * @param document The document
+	 * @return <code>true</code> if each line from <code>startLine</code>
+	 *             to and including <code>endLine</code> is empty
+	 */
+	private boolean isBlockEmpty(int startLine, int endLine, IDocument document) {
+		try {
+			for (int i= startLine; i <= endLine; i++) {
+				IRegion line= document.getLineInformation(i);
+				String text= document.get(line.getOffset(), line.getLength());
+	
+				boolean isEmptyLine = text.trim().length() == 0;
+				if(!isEmptyLine) {
+					return false;
+				}
+			}
+			return true;
+		} catch (BadLocationException e) {
+			MakeUIPlugin.log(e);  // Should not happen
+		}
+	
+		return false;
+	}
+
+	/**
+	 * Implementation of the <code>IUpdate</code> prototype method discovers
+	 * the operation through the current editor's
+	 * <code>ITextOperationTarget</code> adapter, and sets the enabled state
+	 * accordingly.
+	 */
+	@Override
+	public void update() {
+		super.update();
+
+		if (!canModifyEditor()) {
+			setEnabled(false);
+			return;
+		}
+
+		ITextEditor editor= getTextEditor();
+		if (fOperationTarget == null && editor != null)
+			fOperationTarget= editor.getAdapter(ITextOperationTarget.class);
+
+		boolean isEnabled= (fOperationTarget != null && fOperationTarget.canDoOperation(ITextOperationTarget.PREFIX) &&
+				fOperationTarget.canDoOperation(ITextOperationTarget.STRIP_PREFIX));
+		setEnabled(isEnabled);
+	}
+
+	@Override
+	public void setEditor(ITextEditor editor) {
+		super.setEditor(editor);
+		fOperationTarget= null;
+	}
+
+	/**
+	 * For the different content types, get its default comment prefix and store the prefixes.
+	 * @param sourceViewer the source viewer to be configured by this configuration
+	 * @param configuration sourceViewer configuration
+	 */
+	public void configure(ISourceViewer sourceViewer, SourceViewerConfiguration configuration) {
+		fPrefixesMap= null;
+
+		String[] types= configuration.getConfiguredContentTypes(sourceViewer);
+		Map<String, String[]> prefixesMap= new HashMap<String, String[]>(types.length);
+		for (String type : types) {
+			String[] prefixes= configuration.getDefaultPrefixes(sourceViewer, type);
+			if (prefixes != null && prefixes.length > 0) {
+				int emptyPrefixes= 0;
+				for (String prefixe : prefixes) {
+					if (prefixe.length() == 0)
+						emptyPrefixes++;
+				}
+
+				if (emptyPrefixes > 0) {
+					String[] nonemptyPrefixes= new String[prefixes.length - emptyPrefixes];
+					for (int j= 0, k= 0; j < prefixes.length; j++) {
+						String prefix= prefixes[j];
+						if (prefix.length() != 0) {
+							nonemptyPrefixes[k]= prefix;
+							k++;
+						}
+					}
+					prefixes= nonemptyPrefixes;
+				}
+
+				prefixesMap.put(type, prefixes);
+			}
+		}
+		fDocumentPartitioning= configuration.getConfiguredDocumentPartitioning(sourceViewer);
+		fPrefixesMap= prefixesMap;
+	}
+}