/*

 * Copyright (c) 2012, 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

 * or visit www.oracle.com if you need additional information or have any

 * questions.

 */

package shapegen;

import shapegen.ClassCase.Kind;

import java.util.ArrayList;

import java.util.List;

import java.util.Set;

import static shapegen.ClassCase.Kind.*;

/**

 * Type Template Node

 *

 * @author Robert Field

 */

public class TTNode {

    final List<TTNode> supertypes;

    final boolean canBeClass;

    private int currentKindIndex;

    private Kind[] kinds;

    public TTNode(List<TTNode> subtypes, boolean canBeClass) {

        this.supertypes = subtypes;

        this.canBeClass = canBeClass;

    }

    public void start(boolean includeClasses) {

        kinds =

             supertypes.isEmpty()?

                (new Kind[]{IDEFAULT, IPRESENT})

             :  ((includeClasses && canBeClass)?

                  new Kind[]{CNONE, IVAC, IDEFAULT, IPRESENT}

                : new Kind[]{IVAC, IDEFAULT, IPRESENT});

        currentKindIndex = 0;

        for (TTNode sub : supertypes) {

            sub.start(includeClasses);

        }

    }

    public boolean next() {

        ++currentKindIndex;

        if (currentKindIndex >= kinds.length) {

            currentKindIndex = 0;

            return false;

        } else {

            return true;

        }

    }

    public void collectAllSubtypes(Set<TTNode> subs) {

        subs.add(this);

        for (TTNode n : supertypes) {

            n.collectAllSubtypes(subs);

        }

    }

    private Kind getKind() {

        return kinds[currentKindIndex];

    }

    boolean isInterface() {

        return getKind().isInterface;

    }

    boolean isClass() {

        return !isInterface();

    }

    boolean hasDefault() {

        return getKind() == IDEFAULT;

    }

    public boolean isValid() {

        for (TTNode n : supertypes) {

            if (!n.isValid() || (isInterface() && n.isClass())) {

                return false;

            }

        }

        return true;

    }

    public ClassCase genCase() {

        ClassCase subclass;

        List<TTNode> ttintfs;

        if (isClass() && !supertypes.isEmpty() && supertypes.get(0).isClass()) {

            subclass = supertypes.get(0).genCase();

            ttintfs = supertypes.subList(1, supertypes.size());

        } else {

            subclass = null;

            ttintfs = supertypes;

        }

        List<ClassCase> intfs = new ArrayList<>();

        for (TTNode node : ttintfs) {

            intfs.add(node.genCase());

        }

        return new ClassCase(getKind(), subclass, intfs);

    }

}