/*
 *                 Sun Public License Notice
 *
 * The contents of this file are subject to the Sun Public License
 * Version 1.0 (the "License"). You may not use this file except in
 * compliance with the License. A copy of the License is available at
 * http://www.sun.com/
 *
 * The Original Code is NetBeans. The Initial Developer of the Original
 * Code is Sun Microsystems, Inc. Portions Copyright 1997-2003 Sun
 * Microsystems, Inc. All Rights Reserved.
 */

package org.netbeans.modules.javacore.jmiimpl.javamodel;

/**
 * Represents one diff record in the source. Provides data structure for
 * creating diff list. Contains start offset of change, end offset and
 * the new text for this range.
 *
 * @author  Pavel Flaska
 */
class DiffElement {

    private final int startOffset;
    private final int endOffset;
    private final String text;

    /**
     * Instances represent one diff record. One instance defines range of
     * change in original source text and new text. Value cannot be null.
     *
     * @param startOffset where to start replacement
     * @param endOffset   where to end replacement
     * @param value       new text to use
     */    
    public DiffElement(int startOffset, int endOffset, String text) {
        //assert startOffset > endOffset : "startOffset > endOffset";
        //assert startOffset == endOffset && value.length() == 0 : "no operation";
        this.startOffset = startOffset;
        this.endOffset = endOffset;
        this.text = text;
    }

    /**
     * Getter for property startOffset.
     *
     * @return Value of property startOffset.
     */
    public int getStartOffset() {
        return startOffset;
    }    

    /**
     * Getter for property endOffset.
     *
     * @return Value of property endOffset.
     */
    public int getEndOffset() {
        return endOffset;
    }

    /**
     * Getter for property text.
     *
     * @return Value of property text.
     */
    public String getText() {
        return text;
    }

    /**
     * Returns true, if the record is newly inserted (i.e. it doesn't
     * replace anything in the original code).
     *
     * @return  true, if the diff is inserted code
     */
    public boolean isInserted() {
        return startOffset == endOffset;
    }
    
    /**
     *
     * @return true, if the diff is deleted code
     */
    public boolean isDeleted() {
        return startOffset < endOffset && text.length() == 0;
    }
}