/*
 * Copyright (c) 2014, Oracle and/or its affiliates. All rights reserved.
 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
 *
 * This code is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License version 2 only, as
 * published by the Free Software Foundation.  Oracle designates this
 * particular file as subject to the "Classpath" exception as provided
 * by Oracle in the LICENSE file that accompanied this code.
 *
 * This code 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 GNU General Public License
 * version 2 for more details (a copy is included in the LICENSE file that
 * accompanied this code).
 *
 * You should have received a copy of the GNU General Public License version
 * 2 along with this work; if not, write to the Free Software Foundation,
 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
 *
 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
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package hello.dialog.wizard;

import java.util.ArrayList;
import java.util.Arrays;
import java.util.Collection;
import java.util.List;
import java.util.Optional;

import hello.dialog.wizard.Wizard.WizardPane;

public class LinearWizardFlow implements Wizard.Flow {

    private final List<WizardPane> pages;

    public LinearWizardFlow( Collection<WizardPane> pages ) {
        this.pages = new ArrayList<>(pages);
    }

    public LinearWizardFlow( WizardPane... pages ) {
        this( Arrays.asList(pages));
    }

    @Override
    public Optional<WizardPane> advance(WizardPane currentPage) {
        int pageIndex = pages.indexOf(currentPage);
        return Optional.ofNullable( pages.get(++pageIndex) );
    }

    @Override
    public boolean canAdvance(WizardPane currentPage) {
        int pageIndex = pages.indexOf(currentPage);
        return pages.size()-1 > pageIndex;
    }



}