/*   
ZZText.java
 *    
 *    Copyright (c) 2000, Ted Nelson and Tuomas Lukka
 *
 *    You may use and distribute under the terms of either the GNU Lesser
 *    General Public License, either version 2 of the license or,
 *    at your choice, any later version. Alternatively, you may use and
 *    distribute under the terms of the XPL.
 *
 *    See the LICENSE.lgpl and LICENSE.xpl files for the specific terms of 
 *    the licenses.
 *
 *    This software is distributed in the hope that it will be useful,
 *    but WITHOUT ANY WARRANTY; without even the implied warranty of
 *    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the README
 *    file for more details.
 *
 */
/*
 * Written by Tuomas Lukka
 */
package org.gzigzag;
import java.awt.*;

/** An interface for getting or putting text in cells.
 * Used e.g. to implement multilingual text.
 * Handles referential text as well.
 */

public abstract class ZZText {
public static final String rcsid = "$Id: ZZText.java,v 1.2 2000/10/19 17:04:26 tjl Exp $";

    /** Get the string in a given cell, whether referential or non-referential.
     */
    public abstract String getText(ZZCell c);

    /** Set the string in the given cell non-referentially.
     */
    public abstract void setText(ZZCell c, String s);

    /** Whether a given cell is referential.
     */
    public abstract boolean isRef(ZZCell c);

    /** Insert the given text into the cell.
     * If the cell is referential, insert referentially by creating
     * a new Span for this text. Else just handle characters.
     */
    public void insert(ZZCell c, String txt, int offs) {
	if(isRef(c)) {
	    insertNewRef(c, txt, offs);
	} else {
	    String s = getText(c);
	    setText(c, s.substring(0, offs) + txt + s.substring(offs));
	}
    }

    /** Delete a span of text from this cell.
     */
    public abstract void delete(ZZCell c, int start);

    /** Delete a span of text from this cell.
     */
    public abstract void delete(ZZCell c, int start, int end);

    /** Split a cell into two along a dimension.
     * 0..offs-1 goes into first, offs..end goes to next.
     * All connections remain in the first cell.
     */
    public void split(ZZCell c, int offs, String dim) {
	ZZCell n = c.N(dim);
	if(isRef(c)) {
	    Span[] sps = getSpans(c, offs);
	    setSpans(n, sps);
	    delete(c, offs);
	} else {
	    String s = getText(c);
	    setText(c, s.substring(0, offs));
	    setText(n, s.substring(offs));
	}
    }

    /** Insert a string of typed-in text referentially.
     * A Span in the current cell's space is automatically constructed, etc.
     * This is at this level because we *may* want to fudge things later if
     * the user corrects typing errors before saving. However, that's a 
     * bit tricky
     * so we won't try it yet.
     * <p>
     * Calling this function on a cell that only has text content 
     * makes the whole
     * current text content referential as well.
     */
    public abstract void insertNewRef(ZZCell c, String txt, int offs);

    /** Insert a referential span of text.
     * <p>
     * Calling this function on a cell that only has text content 
     * makes the whole
     * current text content referential as well.
     */
    public abstract void insertRef(ZZCell c, Span sp, int offs);

    /** Obtain the referential contents of this cell.
     * @return List of spans, or null if not referential.
     */
    public abstract Span[] getSpans(ZZCell c);
    public abstract Span[] getSpans(ZZCell c, int start);
    public abstract Span[] getSpans(ZZCell c, int start, int end);

    /** Set the spans of the cell to the given spans.
     */
    public abstract void setSpans(ZZCell c, Span[] spans);
    

}