/*
 * [ByAuthor.java]
 *
 * Summary: Comparator to sort HTML menu items by author then title.
 *
 * Copyright: (c) 2002-2017 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:
 *  2.0 2007-04-12 merge versions from Acer and Steve.
 */
package com.mindprod.stores;

import java.util.Comparator;

/**
 * Comparator to sort HTML menu items by author then title.
 *
 * @author Roedy Green, Canadian Mind Products
 * @version 2.0 2007-04-12 merge versions from Acer and Steve.
 * @since 2002
 */
class ByAuthor implements Comparator<String>
    {
    public int compare( String o1, String o2 )
        {
        // line looks like
        // {<a href="#HEGEMONY">Hegemony Or Survival</a> by Noam Chomsky}
        // or {<a href="#MISSIONACCOMPLISHED">Mission Accomplished</a> by Christopher Cerf and Victor S. Navasky}
        final int b1 = o1.indexOf( " by " );
        final int b2 = o2.indexOf( " by " );
        if ( b1 < 0 )
            {
            throw new IllegalArgumentException( "missing by " + o1 );
            }
        if ( b2 < 0 )
            {
            throw new IllegalArgumentException( "missing by " + o2 );
            }
        final int t1 = o1.indexOf( " and ", b1 + 4 );
        final int t2 = o2.indexOf( " and ", b2 + 4 );
        final String tail1;
        final String tail2;
        if ( t1 < 0 )
            {
            tail1 = o1.substring( b1 + 4 );
            }
        else
            {
            tail1 = o1.substring( 0, t1 );
            }
        if ( t2 < 0 )
            {
            tail2 = o2.substring( b2 + 4 );
            }
        else
            {
            tail2 = o2.substring( 0, t2 );
            }
        final String surname1 = tail1.substring( tail1.lastIndexOf( ' ' ) + 1 );
        final String surname2 = tail2.substring( tail2.lastIndexOf( ' ' ) + 1 );
        int diff = surname1.compareToIgnoreCase( surname2 );
        if ( diff != 0 )
            {
            return diff;
            }
        // break tie by examining title.
        final int g1 = o1.indexOf( '>' );
        final int g2 = o2.indexOf( '>' );
        if ( g1 < 0 )
            {
            throw new IllegalArgumentException( "missing > " + o1 );
            }
        if ( g2 < 0 )
            {
            throw new IllegalArgumentException( "missing > " + o2 );
            }
        String title1 = o1.substring( g1 + 1 );
        String title2 = o2.substring( g2 + 1 );
        if ( title1.startsWith( "The " ) )
            {
            title1 = title1.substring( 4 );
            }
        if ( title2.startsWith( "The " ) )
            {
            title2 = title2.substring( 4 );
            }
        if ( title1.startsWith( "A " ) )
            {
            title1 = title1.substring( 2 );
            }
        if ( title2.startsWith( "A " ) )
            {
            title2 = title2.substring( 2 );
            }
        return title1.compareToIgnoreCase( title2 );
        }
    }