/*******************************************************************************
 * 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.IDocumentExtension4;

import dwt.dwthelper.utils;

/**
 * Extension interface for {@link dwtx.jface.text.IDocument}. It adds the
 * following concepts:
 * <ul>
 *   <li>Rewrite sessions. A rewrite session is a sequence of replace operations
 *       that form a semantic unit.</li> 
 *   <li>A modification stamp on the document</li>
 *   <li>The ability to set the initial line delimiter and to query the default
 *       line delimiter</li>
 * </ul>
 * 
 * @since 3.1
 */
public interface IDocumentExtension4 {

    /**
     * Tells the document that it is about to be rewritten. That is, a sequence
     * of replace operations that form a semantic unit will be performed on this
     * document. A specification of the nature of the operation sequence is
     * given in form of the session type.
     * <p>
     * The document is considered being in rewrite mode as long as
     * <code>stopRewriteSession</code> has not been called.
     *
     * @param sessionType the session type
     * @return the started rewrite session
     * @throws IllegalStateException in case there is already an active rewrite session
     */
    DocumentRewriteSession startRewriteSession(DocumentRewriteSessionType sessionType) throws IllegalStateException;

    /**
     * Tells the document to stop the rewrite session. This method has only any
     * effect if <code>startRewriteSession</code> has been called before.
     * <p>
     * This method does not have any effect if the given session is not the
     * active rewrite session.
     *
     * @param session the session to stop
     */
    void stopRewriteSession(DocumentRewriteSession session);

    /**
     * Returns the active rewrite session of this document or <code>null</code>.
     *
     * @return the active rewrite session or <code>null</code>
     */
    DocumentRewriteSession getActiveRewriteSession();

    /**
     * Registers the document rewrite session listener with the document. After
     * registration the <code>IDocumentRewriteSessionListener</code> is
     * informed about each state change of rewrite sessions performed on this
     * document.
     * <p>
     * If the listener is already registered nothing happens.
     * <p>
     * An <code>IRewriteSessionDocumentListener</code> may call back to this
     * document when being inside a document notification.
     *
     * @param listener the listener to be registered
     */
    void addDocumentRewriteSessionListener(IDocumentRewriteSessionListener listener);

    /**
     * Removes the listener from the document's list of document rewrite session
     * listeners. If the listener is not registered with the document nothing
     * happens.
     * <p>
     * An <code>IDocumentRewriteSessionListener</code> may call back to this
     * document when being inside a document notification.
     *
     * @param listener the listener to be removed
     */
    void removeDocumentRewriteSessionListener(IDocumentRewriteSessionListener listener);

    /**
     * Substitutes the given text for the specified document range.
     * Sends a <code>DocumentEvent</code> to all registered <code>IDocumentListener</code>.
     *
     * @param offset the document offset
     * @param length the length of the specified range
     * @param text the substitution text
     * @param modificationStamp of the document after replacing
     * @exception BadLocationException if the offset is invalid in this document
     *
     * @see DocumentEvent
     * @see IDocumentListener
     */
    void replace(int offset, int length, String text, long modificationStamp) throws BadLocationException;

    /**
     * Replaces the content of the document with the given text.
     * Sends a <code>DocumentEvent</code> to all registered <code>IDocumentListener</code>.
     * This method is a convenience method for <code>replace(0, getLength(), text)</code>.
     *
     * @param text the new content of the document
     * @param modificationStamp of the document after setting the content
     *
     * @see DocumentEvent
     * @see IDocumentListener
     */
    void set(String text, long modificationStamp);

    /**
     * The unknown modification stamp.
     */
    long UNKNOWN_MODIFICATION_STAMP= -1;

    /**
     * Returns the modification stamp of this document. The modification stamp
     * is updated each time a modifying operation is called on this document. If
     * two modification stamps of the same document are identical then the document
     * content is too, however, same content does not imply same modification stamp.
     * <p>
     * The magnitude or sign of the numerical difference between two modification stamps
     * is not significant.
     * </p>
     *
     * @return the modification stamp of this document or <code>UNKNOWN_MODIFICATION_STAMP</code>
     */
    long getModificationStamp();
    
    /**
     * Returns this document's default line delimiter.
     * <p>
     * This default line delimiter should be used by clients who
     * want unique delimiters (e.g. 'CR's) in the document.</p> 
     *
     * @return the default line delimiter or <code>null</code> if none
     */
    String getDefaultLineDelimiter();
    
    /**
     * Sets this document's initial line delimiter i.e. the one
     * which is returned by <code>getDefaultLineDelimiter</code>
     * if the document does not yet contain any line delimiter.
     *
     * @param lineDelimiter the default line delimiter
     */
    void setInitialLineDelimiter(String lineDelimiter);
}