/*
 * Copyright (C) 2012 Google Inc. All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are
 * met:
 *
 *     * Redistributions of source code must retain the above copyright
 * notice, this list of conditions and the following disclaimer.
 *     * Redistributions in binary form must reproduce the above
 * copyright notice, this list of conditions and the following disclaimer
 * in the documentation and/or other materials provided with the
 * distribution.
 *     * Neither the name of Google Inc. nor the names of its
 * contributors may be used to endorse or promote products derived from
 * this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */

#ifndef InspectorHistory_h
#define InspectorHistory_h

#include "wtf/OwnPtr.h"
#include "wtf/Vector.h"
#include "wtf/text/WTFString.h"

namespace WebCore {

class ExceptionState;

class InspectorHistory FINAL {
    WTF_MAKE_NONCOPYABLE(InspectorHistory); WTF_MAKE_FAST_ALLOCATED;
public:
    class Action {
        WTF_MAKE_FAST_ALLOCATED;
    public:
        Action(const String& name);
        virtual ~Action();
        virtual String toString();

        virtual String mergeId();
        virtual void merge(PassOwnPtr<Action>);

        virtual bool perform(ExceptionState&) = 0;

        virtual bool undo(ExceptionState&) = 0;
        virtual bool redo(ExceptionState&) = 0;

        virtual bool isUndoableStateMark();
    private:
        String m_name;
    };

    InspectorHistory();

    bool perform(PassOwnPtr<Action>, ExceptionState&);
    void markUndoableState();

    bool undo(ExceptionState&);
    bool redo(ExceptionState&);
    void reset();

private:
    Vector<OwnPtr<Action> > m_history;
    size_t m_afterLastActionIndex;
};


} // namespace WebCore

#endif // !defined(InspectorHistory_h)