indexIterator.h

/* Copyright (c) 2011-2014, Stefan.Eilemann@epfl.ch
 *
 * This file is part of Lunchbox <https://github.com/Eyescale/Lunchbox>
 *
 * This library is free software; you can redistribute it and/or modify it under
 * the terms of the GNU Lesser General Public License version 3.0 as published
 * by the Free Software Foundation.
 *
 * This library 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 Lesser General Public License for more
 * details.
 *
 * You should have received a copy of the GNU Lesser General Public License
 * along with this library; if not, write to the Free Software Foundation, Inc.,
 * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
 */

#ifndef LUNCHBOX_INDEXITERATOR_H
#define LUNCHBOX_INDEXITERATOR_H

namespace lunchbox
{
template <class S, class C, class T>
class IndexIterator : public std::iterator<std::random_access_iterator_tag, T>
{
public:
    IndexIterator(C* container, const size_t i)
        : container_(container)
        , i_(i)
    {
    }

    explicit IndexIterator(const S& from)
        : container_(from.container_)
        , i_(from.i_)
    {
    }

    template <class U, class V, class W>
    IndexIterator(const IndexIterator<U, V, W>& from)
        : container_(from.container_)
        , i_(from.i_)
    {
    }

    // cppcheck-suppress operatorEq
    S& operator=(const IndexIterator& rhs)
    {
        container_ = rhs.container_;
        i_ = rhs.i_;
        return *static_cast<S*>(this);
    }

    template <class U, class W>
    S& operator=(const IndexIterator<S, U, W>& rhs)
    {
        container_ = rhs.container_;
        i_ = rhs.i_;
        return *static_cast<S*>(this);
    }

    S& operator++()
    {
        ++i_;
        return *static_cast<S*>(this);
    }

    S& operator--()
    {
        --i_;
        return *static_cast<S*>(this);
    }

    S operator++(int) { return S(container_, i_++); }
    S operator--(int) { return S(container_, i_--); }
    S operator+(const size_t& n) const { return S(container_, i_ + n); }
    S& operator+=(const size_t& n)
    {
        i_ += n;
        return *static_cast<S*>(this);
    }

    S operator-(const size_t& n) const { return S(container_, i_ - n); }
    S& operator-=(const size_t& n)
    {
        i_ -= n;
        return *static_cast<S*>(this);
    }

    ssize_t operator-(const S& n) const { return i_ - n.i_; }
    bool operator==(const S& rhs) const
    {
        return container_ == rhs.container_ && i_ == rhs.i_;
    }

    bool operator!=(const S& rhs) const
    {
        return container_ != rhs.container_ || i_ != rhs.i_;
    }

    bool operator<(const S& rhs) const
    {
        return container_ <= rhs.container_ && i_ < rhs.i_;
    }

    bool operator>(const S& rhs) const
    {
        return container_ >= rhs.container_ && i_ > rhs.i_;
    }

    bool operator<=(const S& rhs) const
    {
        return container_ <= rhs.container_ && i_ <= rhs.i_;
    }

    bool operator>=(const S& rhs) const
    {
        return container_ >= rhs.container_ && i_ >= rhs.i_;
    }

    size_t getPosition() const { return i_; }
protected:
    C* container_;
    size_t i_;

    // template copy ctor
    template <class, class, class>
    friend class IndexIterator;

private:
    IndexIterator();
};
}

#endif // LUNCHBOX_INDEXITERATOR_H