/*******************************************************************************
 * Copyright (c) 2000, 2005 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.ITextViewerExtension;

import dwtx.jface.text.IRewriteTarget; // packageimport

import dwt.dwthelper.utils;

import dwt.custom.VerifyKeyListener;
import dwt.widgets.Control;


/**
 * Extension interface for {@link dwtx.jface.text.ITextViewer}.
 * <p>
 * This extension interface replaces the event consumer mechanism (
 * {@link dwtx.jface.text.ITextViewer#setEventConsumer(IEventConsumer)})
 * with a set of methods that allow to manage a sequence of
 * {@link dwt.custom.VerifyKeyListener}objects. It also adds
 * <ul>
 * <li>access to the control of this viewer</li>
 * <li>marked region support as in emacs</li>
 * <li>control of the viewer's redraw behavior by introducing
 *     <code>setRedraw(bool)</code>
 * <li>access to the viewer's rewrite target.
 * </ul>
 *
 * A rewrite target ({@link dwtx.jface.text.IRewriteTarget}) represents
 * an facade offering the necessary methods to manipulate a document that is the
 * input document of a text viewer.
 *
 * @since 2.0
 */
public interface ITextViewerExtension {

    /**
     * Inserts the verify key listener at the beginning of the viewer's list of
     * verify key listeners. If the listener is already registered with the
     * viewer this call moves the listener to the beginning of the list.
     *
     * @param listener the listener to be inserted
     */
    void prependVerifyKeyListener(VerifyKeyListener listener);

    /**
     * Appends a verify key listener to the viewer's list of verify key
     * listeners. If the listener is already registered with the viewer this
     * call moves the listener to the end of the list.
     *
     * @param listener the listener to be added
     */
    void appendVerifyKeyListener(VerifyKeyListener listener);

    /**
     * Removes the verify key listener from the viewer's list of verify key listeners.
     * If the listener is not registered with this viewer, this call has no effect.
     *
     * @param listener the listener to be removed
     */
    void removeVerifyKeyListener(VerifyKeyListener listener);

    /**
     * Returns the control of this viewer.
     *
     * @return the control of this viewer
     */
    Control getControl();

    /**
     * Sets a mark at the given offset or clears the mark if the specified
     * offset is <code>-1</code>. If a mark is set and the selection is
     * empty, cut and copy actions performed on this text viewer work on the
     * region described by the positions of the mark and the cursor.
     *
     * @param offset the offset of the mark
     */
    void setMark(int offset);

    /**
     * Returns the position of the mark, <code>-1</code> if the mark is not set.
     *
     * @return the position of the mark or <code>-1</code> if no mark is set
     */
    int getMark();

    /**
     * Enables/disables the redrawing of this text viewer. This temporarily
     * disconnects the viewer from its underlying
     * {@link dwt.custom.StyledText}widget. While being
     * disconnected only the viewer's selection may be changed using
     * <code>setSelectedRange</code>. Any direct manipulation of the widget
     * as well as calls to methods that change the viewer's presentation state
     * (such as enabling the segmented view) are not allowed. When redrawing is
     * disabled the viewer does not send out any selection or view port change
     * notification. When redrawing is enabled again, a selection change
     * notification is sent out for the selected range and this range is
     * revealed causing a view port changed notification.
     *
     * @param redraw <code>true</code> to enable redrawing, <code>false</code>
     *            otherwise
     */
    void setRedraw(bool redraw);

    /**
     * Returns the viewer's rewrite target.
     *
     * @return the viewer's rewrite target
     */
    IRewriteTarget getRewriteTarget();
}