--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/dwtx/jface/text/AbstractLineTracker.d	Sat Aug 23 19:10:48 2008 +0200
@@ -0,0 +1,321 @@
+/*******************************************************************************
+ * Copyright (c) 2000, 2006 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
+ * Port to the D programming language:
+ *     Frank Benoit <benoit@tionex.de>
+ *******************************************************************************/
+module dwtx.jface.text.AbstractLineTracker;
+
+import dwt.dwthelper.utils;
+
+import java.util.ArrayList;
+import java.util.Iterator;
+import java.util.List;
+
+/**
+ * Abstract implementation of <code>ILineTracker</code>. It lets the definition of line
+ * delimiters to subclasses. Assuming that '\n' is the only line delimiter, this abstract
+ * implementation defines the following line scheme:
+ * <ul>
+ * <li> "" -> [0,0]
+ * <li> "a" -> [0,1]
+ * <li> "\n" -> [0,1], [1,0]
+ * <li> "a\n" -> [0,2], [2,0]
+ * <li> "a\nb" -> [0,2], [2,1]
+ * <li> "a\nbc\n" -> [0,2], [2,3], [5,0]
+ * </ul>
+ * <p>
+ * This class must be subclassed.
+ * </p>
+ */
+public abstract class AbstractLineTracker : ILineTracker, ILineTrackerExtension {
+
+    /**
+     * Tells whether this class is in debug mode.
+     * 
+     * @since 3.1
+     */
+    private static final bool DEBUG= false;
+
+    /**
+     * Combines the information of the occurrence of a line delimiter. <code>delimiterIndex</code>
+     * is the index where a line delimiter starts, whereas <code>delimiterLength</code>,
+     * indicates the length of the delimiter.
+     */
+    protected static class DelimiterInfo {
+        public int delimiterIndex;
+        public int delimiterLength;
+        public String delimiter;
+    }
+
+    /**
+     * Representation of replace and set requests.
+     * 
+     * @since 3.1
+     */
+    protected static class Request {
+        public final int offset;
+        public final int length;
+        public final String text;
+
+        public Request(int offset, int length, String text) {
+            this.offset= offset;
+            this.length= length;
+            this.text= text;
+        }
+
+        public Request(String text) {
+            this.offset= -1;
+            this.length= -1;
+            this.text= text;
+        }
+
+        public bool isReplaceRequest() {
+            return this.offset > -1 && this.length > -1;
+        }
+    }
+
+    /**
+     * The active rewrite session.
+     * 
+     * @since 3.1
+     */
+    private DocumentRewriteSession fActiveRewriteSession;
+    /**
+     * The list of pending requests.
+     * 
+     * @since 3.1
+     */
+    private List fPendingRequests;
+    /**
+     * The implementation that this tracker delegates to.
+     * 
+     * @since 3.2
+     */
+    private ILineTracker fDelegate= new ListLineTracker() {
+        public String[] getLegalLineDelimiters() {
+            return AbstractLineTracker.this.getLegalLineDelimiters();
+        }
+
+        protected DelimiterInfo nextDelimiterInfo(String text, int offset) {
+            return AbstractLineTracker.this.nextDelimiterInfo(text, offset);
+        }
+    };
+    /**
+     * Whether the delegate needs conversion when the line structure is modified.
+     */
+    private bool fNeedsConversion= true;
+
+    /**
+     * Creates a new line tracker.
+     */
+    protected AbstractLineTracker() {
+    }
+
+    /*
+     * @see dwtx.jface.text.ILineTracker#computeNumberOfLines(java.lang.String)
+     */
+    public int computeNumberOfLines(String text) {
+        return fDelegate.computeNumberOfLines(text);
+    }
+
+    /*
+     * @see dwtx.jface.text.ILineTracker#getLineDelimiter(int)
+     */
+    public String getLineDelimiter(int line) throws BadLocationException {
+        checkRewriteSession();
+        return fDelegate.getLineDelimiter(line);
+    }
+
+    /*
+     * @see dwtx.jface.text.ILineTracker#getLineInformation(int)
+     */
+    public IRegion getLineInformation(int line) throws BadLocationException {
+        checkRewriteSession();
+        return fDelegate.getLineInformation(line);
+    }
+
+    /*
+     * @see dwtx.jface.text.ILineTracker#getLineInformationOfOffset(int)
+     */
+    public IRegion getLineInformationOfOffset(int offset) throws BadLocationException {
+        checkRewriteSession();
+        return fDelegate.getLineInformationOfOffset(offset);
+    }
+
+    /*
+     * @see dwtx.jface.text.ILineTracker#getLineLength(int)
+     */
+    public int getLineLength(int line) throws BadLocationException {
+        checkRewriteSession();
+        return fDelegate.getLineLength(line);
+    }
+
+    /*
+     * @see dwtx.jface.text.ILineTracker#getLineNumberOfOffset(int)
+     */
+    public int getLineNumberOfOffset(int offset) throws BadLocationException {
+        checkRewriteSession();
+        return fDelegate.getLineNumberOfOffset(offset);
+    }
+
+    /*
+     * @see dwtx.jface.text.ILineTracker#getLineOffset(int)
+     */
+    public int getLineOffset(int line) throws BadLocationException {
+        checkRewriteSession();
+        return fDelegate.getLineOffset(line);
+    }
+
+    /*
+     * @see dwtx.jface.text.ILineTracker#getNumberOfLines()
+     */
+    public int getNumberOfLines() {
+        try {
+            checkRewriteSession();
+        } catch (BadLocationException x) {
+            // TODO there is currently no way to communicate that exception back to the document
+        }
+        return fDelegate.getNumberOfLines();
+    }
+
+    /*
+     * @see dwtx.jface.text.ILineTracker#getNumberOfLines(int, int)
+     */
+    public int getNumberOfLines(int offset, int length) throws BadLocationException {
+        checkRewriteSession();
+        return fDelegate.getNumberOfLines(offset, length);
+    }
+
+    /*
+     * @see dwtx.jface.text.ILineTracker#set(java.lang.String)
+     */
+    public void set(String text) {
+        if (hasActiveRewriteSession()) {
+            fPendingRequests.clear();
+            fPendingRequests.add(new Request(text));
+            return;
+        }
+
+        fDelegate.set(text);
+    }
+
+    /*
+     * @see dwtx.jface.text.ILineTracker#replace(int, int, java.lang.String)
+     */
+    public void replace(int offset, int length, String text) throws BadLocationException {
+        if (hasActiveRewriteSession()) {
+            fPendingRequests.add(new Request(offset, length, text));
+            return;
+        }
+
+        checkImplementation();
+
+        fDelegate.replace(offset, length, text);
+    }
+
+    /**
+     * Converts the implementation to be a {@link TreeLineTracker} if it isn't yet.
+     * 
+     * @since 3.2
+     */
+    private void checkImplementation() {
+        if (fNeedsConversion) {
+            fNeedsConversion= false;
+            fDelegate= new TreeLineTracker((ListLineTracker) fDelegate) {
+                protected DelimiterInfo nextDelimiterInfo(String text, int offset) {
+                    return AbstractLineTracker.this.nextDelimiterInfo(text, offset);
+                }
+
+                public String[] getLegalLineDelimiters() {
+                    return AbstractLineTracker.this.getLegalLineDelimiters();
+                }
+            };
+        }
+    }
+
+    /**
+     * Returns the information about the first delimiter found in the given text starting at the
+     * given offset.
+     * 
+     * @param text the text to be searched
+     * @param offset the offset in the given text
+     * @return the information of the first found delimiter or <code>null</code>
+     */
+    protected abstract DelimiterInfo nextDelimiterInfo(String text, int offset);
+
+    /*
+     * @see dwtx.jface.text.ILineTrackerExtension#startRewriteSession(dwtx.jface.text.DocumentRewriteSession)
+     * @since 3.1
+     */
+    public final void startRewriteSession(DocumentRewriteSession session) {
+        if (fActiveRewriteSession !is null)
+            throw new IllegalStateException();
+        fActiveRewriteSession= session;
+        fPendingRequests= new ArrayList(20);
+    }
+
+    /*
+     * @see dwtx.jface.text.ILineTrackerExtension#stopRewriteSession(dwtx.jface.text.DocumentRewriteSession, java.lang.String)
+     * @since 3.1
+     */
+    public final void stopRewriteSession(DocumentRewriteSession session, String text) {
+        if (fActiveRewriteSession is session) {
+            fActiveRewriteSession= null;
+            fPendingRequests= null;
+            set(text);
+        }
+    }
+
+    /**
+     * Tells whether there's an active rewrite session.
+     * 
+     * @return <code>true</code> if there is an active rewrite session, <code>false</code>
+     *         otherwise
+     * @since 3.1
+     */
+    protected final bool hasActiveRewriteSession() {
+        return fActiveRewriteSession !is null;
+    }
+
+    /**
+     * Flushes the active rewrite session.
+     * 
+     * @throws BadLocationException in case the recorded requests cannot be processed correctly
+     * @since 3.1
+     */
+    protected final void flushRewriteSession() throws BadLocationException {
+        if (DEBUG)
+            System.out.println("AbstractLineTracker: Flushing rewrite session: " + fActiveRewriteSession); //$NON-NLS-1$
+
+        Iterator e= fPendingRequests.iterator();
+
+        fPendingRequests= null;
+        fActiveRewriteSession= null;
+
+        while (e.hasNext()) {
+            Request request= (Request) e.next();
+            if (request.isReplaceRequest())
+                replace(request.offset, request.length, request.text);
+            else
+                set(request.text);
+        }
+    }
+
+    /**
+     * Checks the presence of a rewrite session and flushes it.
+     * 
+     * @throws BadLocationException in case flushing does not succeed
+     * @since 3.1
+     */
+    protected final void checkRewriteSession() throws BadLocationException {
+        if (hasActiveRewriteSession())
+            flushRewriteSession();
+    }
+}