/*
 * [Item.java]
 *
 * Summary: Base class for script items we sort, namely SRItems and PathItems.
 *
 * Copyright: (c) 2011-2017 Roedy Green, Canadian Mind Products, http://mindprod.com
 *
 * Licence: This software may be copied and used freely for any purpose but military.
 *          http://mindprod.com/contact/nonmil.html
 *
 * Requires: JDK 1.8+
 *
 * Created with: JetBrains IntelliJ IDEA IDE http://www.jetbrains.com/idea/
 *
 * Version History:
 *  1.0 2011-11-13 initial version
 */
package com.mindprod.sortsrs;

/**
 * Base class for script items we sort, namely SRItems and PathItems.
 *
 * @author Roedy Green, Canadian Mind Products
 * @version 1.0 2011-11-13 initial version
 * @since 2011-11-13
 */
abstract class Item
    {
    /**
     * which section of the script does this item belong in.
     * 1 = s/r
     * 2 = paths
     * 3. end
     */
    int section;

    /**
     * used to ensure that empty strings are stored consistently as null rather than as "".
     * Does not trim lead or trail blanks. Does not intern.
     *
     * @param field field to store
     *
     * @return null if field empty or null, untouched otherwise.
     */
    static String canonise( String field )
        {
        if ( field == null || field.length() == 0 )
            {
            return null;
            }
        else
            {
            return field;
            }
        }

    /**
     * compose a 1 to 4-line search/replace script item, with lead \r\n but no trailing \r\n
     *
     * @param stripComments true if should strip out comments
     *
     * @return chars as they appear is reconstructed script.
     */
    abstract String combine( final boolean stripComments );
    }