/* Copyright (C) 2004 Garrett A. Kajmowicz
 *
 * This file is part of the uClibc++ Library.
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 2.1 of the License, or (at your option) any later version.
 *
 * 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., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 */

#include <basic_definitions>

#ifndef __STD_HEADER_ITERATOR_BASE
#define __STD_HEADER_ITERATOR_BASE 1

#pragma GCC visibility push(default)

extern "C++"
{

namespace std
{
  template<class Iterator> struct iterator_traits;
  template<class T> struct iterator_traits<T*>;

  template<class Category, class T, class Distance = ptrdiff_t, class Pointer = T*, class Reference = T&> struct iterator;

  struct _UCXXEXPORT input_iterator_tag {};
  struct _UCXXEXPORT output_iterator_tag {};
  struct _UCXXEXPORT forward_iterator_tag: public input_iterator_tag {};
  struct _UCXXEXPORT bidirectional_iterator_tag: public forward_iterator_tag {};
  struct _UCXXEXPORT random_access_iterator_tag: public bidirectional_iterator_tag {};

  template <class InputIterator, class Distance> _UCXXEXPORT void advance(InputIterator& i, Distance n)
  {
    while (n > 0)
    {
      --n;
      ++i;
    }
  }

  template <class InputIterator> _UCXXEXPORT typename iterator_traits<InputIterator>::difference_type
    distance(InputIterator first, InputIterator last)
  {
    typename iterator_traits<InputIterator>::difference_type d = 0;
    while (first++ !=last)
    {
      d++;
    }
    return d;
  }

  // subclause _lib.predef.iterators_, predefined iterators:

  template <class Iterator> class reverse_iterator;
  template <class Iterator> bool operator==(const reverse_iterator<Iterator>& x, const reverse_iterator<Iterator>& y);
  template <class Iterator> bool operator<(const reverse_iterator<Iterator>& x, const reverse_iterator<Iterator>& y);
  template <class Iterator> bool operator!=(const reverse_iterator<Iterator>& x, const reverse_iterator<Iterator>& y);
  template <class Iterator> bool operator>(const reverse_iterator<Iterator>& x, const reverse_iterator<Iterator>& y);
  template <class Iterator> bool operator>=(const reverse_iterator<Iterator>& x, const reverse_iterator<Iterator>& y);
  template <class Iterator> bool operator<=(const reverse_iterator<Iterator>& x, const reverse_iterator<Iterator>& y);
  template <class Iterator> typename reverse_iterator<Iterator>::difference_type
    operator-( const reverse_iterator<Iterator>& x, const reverse_iterator<Iterator>& y);
  template <class Iterator> reverse_iterator<Iterator>
    operator+( typename reverse_iterator<Iterator>::difference_type n, const reverse_iterator<Iterator>& x);
  template <class Container> class back_insert_iterator;
  template <class Container> back_insert_iterator<Container> back_inserter(Container& x);
  template <class Container> class front_insert_iterator;
  template <class Container> front_insert_iterator<Container> front_inserter(Container& x);
  template <class Container> class insert_iterator;
  template <class Container, class Iterator>
    insert_iterator<Container> inserter(Container& x, Iterator i);

  // Actual Template definitions

  template<class Iterator> struct _UCXXEXPORT iterator_traits
  {
    typedef typename Iterator::difference_type difference_type;
    typedef typename Iterator::value_type value_type;
    typedef typename Iterator::pointer pointer;
    typedef typename Iterator::reference reference;
    typedef typename Iterator::iterator_category iterator_category;
  };

  //Pointer specialization - required by standard

  template<class T> struct _UCXXEXPORT iterator_traits<T*>
  {
    typedef ptrdiff_t difference_type;
    typedef T value_type;
    typedef T* pointer;
    typedef T& reference;
    typedef random_access_iterator_tag iterator_category;
  };

  //Specialization recomended by standard

/*  template<class T> struct _UCXXEXPORT iterator_traits<T __far*>
  {
    typedef long difference_type;
    typedef T value_type;
    typedef T __far* pointer;
    typedef T __far& reference;
    typedef random_access_iterator_tag iterator_category;
  };*/

/*  template <class BidirectionalIterator> _UCXXEXPORT void
    reverse(BidirectionalIterator first, BidirectionalIterator last)
  {
    typename iterator_traits<BidirectionalIterator>::difference_type n = distance(first, last);
    --n;
    while(n > 0)
    {
      typename iterator_traits<BidirectionalIterator>::value_type tmp = *first;
      *first++ = * --last;
      *last = tmp;
      n -= 2;
    }
  };*/

  template <class Category, class T, class Distance, class Pointer, class Reference>
    struct _UCXXEXPORT iterator
  {
    typedef T         value_type;
    typedef Distance  difference_type;
    typedef Pointer   pointer;
    typedef Reference reference;
    typedef Category  iterator_category;
  };


  template <class Iterator> class _UCXXEXPORT reverse_iterator
    : public iterator<typename iterator_traits<Iterator>::iterator_category,
    typename iterator_traits<Iterator>::value_type, typename iterator_traits<Iterator>::difference_type,
    typename iterator_traits<Iterator>::pointer, typename iterator_traits<Iterator>::reference>
  {
  protected:
    Iterator current;
    friend bool operator== <Iterator>(const reverse_iterator<Iterator>& x, const reverse_iterator<Iterator>& y);
    friend bool operator< <Iterator>(const reverse_iterator<Iterator>& x, const reverse_iterator<Iterator>& y);

  public:
    typedef Iterator iterator_type;

    reverse_iterator() : current(){};
    explicit reverse_iterator(Iterator x) : current(x) { }
    template<class U> reverse_iterator(const reverse_iterator<U> &x) : current(x.base()){}

    Iterator base() const { return current; }       // explicit

    typename iterator_traits<Iterator>::reference operator*() const { Iterator tmp = current; return *--tmp; }
    typename iterator_traits<Iterator>::pointer   operator->() const { return &(operator*()); }
    typename iterator_traits<Iterator>::reference operator[](typename iterator_traits<Iterator>::difference_type n) const
    {
      return current[-n-1];
    }

    reverse_iterator& operator++(){ --current; return *this;  }
    reverse_iterator  operator++(int) {reverse_iterator tmp = *this; --current; return tmp; }
    reverse_iterator& operator--() { ++ current; return *this; }
    reverse_iterator  operator--(int) {reverse_iterator tmp = *this; ++current; return tmp; }

    reverse_iterator  operator+ (typename iterator_traits<Iterator>::difference_type n) const
    {
      reverse_iterator retval( *this );
      retval+=n;
      return retval;
    }

    reverse_iterator& operator+=(typename iterator_traits<Iterator>::difference_type n)
    {
      current -= n;
      return *this;
    }

    reverse_iterator operator- (typename iterator_traits<Iterator>::difference_type n) const
    {
      reverse_iterator retval( *this );
      retval-=n;
      return retval;
    }

    reverse_iterator& operator-=(typename iterator_traits<Iterator>::difference_type n)
    {
      current += n;
      return *this;
    }
   };

  template <class Iterator> _UCXXEXPORT bool
    operator==(const reverse_iterator<Iterator>& x, const reverse_iterator<Iterator>& y)
  {
    return x.base() == y.base();
  }

  template <class Iterator> _UCXXEXPORT bool
    operator<(const reverse_iterator<Iterator>& x, const reverse_iterator<Iterator>& y)
  {
    return x.base() < y.base();
  }

  template <class Iterator> _UCXXEXPORT bool
    operator!=(const reverse_iterator<Iterator>& x, const reverse_iterator<Iterator>& y)
  {
    return x.base() != y.base();
  }

  template <class Iterator> _UCXXEXPORT bool
    operator>(const reverse_iterator<Iterator>& x, const reverse_iterator<Iterator>& y)
  {
    return x.base() > y.base();
  }

  template <class Iterator> _UCXXEXPORT bool
    operator>=(const reverse_iterator<Iterator>& x, const reverse_iterator<Iterator>& y)
  {
    return x.base() >= y.base();
  }

  template <class Iterator> _UCXXEXPORT bool
    operator<=(const reverse_iterator<Iterator>& x, const reverse_iterator<Iterator>& y)
  {
    return x.base() <= y.base();
  }

  template <class Iterator> _UCXXEXPORT typename reverse_iterator<Iterator>::difference_type
    operator-( const reverse_iterator<Iterator>& x, const reverse_iterator<Iterator>& y)
  {
    return y.base() - x.base();
  }

  template <class Iterator> _UCXXEXPORT reverse_iterator<Iterator>
    operator+(typename reverse_iterator<Iterator>::difference_type n, const reverse_iterator<Iterator>& x)
  {
    return reverse_iterator<Iterator> (x.base() - n);
  }

  template <class Container> class _UCXXEXPORT back_insert_iterator :
    public iterator<output_iterator_tag,void,void,void,void>
  {
  protected:
    Container& container;
  public:
    typedef Container container_type;
    explicit back_insert_iterator(Container& x):container(x) {};

    back_insert_iterator<Container>& operator=(const typename Container::value_type& value)
    {
      container.push_back(value);
      return *this;
    }

    back_insert_iterator<Container>& operator*()
    {
      return *this;
    }

    back_insert_iterator<Container>& operator++()
    {
      return *this;
    }

    back_insert_iterator<Container>  operator++(int)
    {
      return *this;
    }
  };

  template <class Container> _UCXXEXPORT back_insert_iterator<Container>
    back_inserter(Container& x)
  {
    return back_insert_iterator<Container>(x);
  }

  template <class Container> class _UCXXEXPORT front_insert_iterator
    : public iterator<output_iterator_tag,void,void,void,void>
  {
  protected:
    Container& container;
  public:
    typedef Container container_type;
    explicit front_insert_iterator(Container& x): container(x) {}

    front_insert_iterator<Container>& operator=(const typename Container::value_type& value)
    {
      container.push_front(value);
      return *this;
    }

    front_insert_iterator<Container>& operator*() { return *this; }
    front_insert_iterator<Container>& operator++() { return *this; }
    front_insert_iterator<Container> operator++(int) { return *this; }
  };

  template <class Container> _UCXXEXPORT front_insert_iterator<Container>
    front_inserter(Container& x)
  {
    return front_insert_iterator<Container>(x);
  }

  template <class Container> class _UCXXEXPORT insert_iterator
    : public iterator<output_iterator_tag,void,void,void,void>
  {
  protected:
    Container& container;
    typename Container::iterator iter;
  public:
    typedef Container container_type;
    insert_iterator(Container& x, typename Container::iterator i) : container(x), iter(i) {}

    insert_iterator<Container>& operator=(const typename Container::value_type& value)
    {
      iter = container.insert(iter, value);
      ++iter;
      return *this;
    }

    insert_iterator<Container>& operator*() { return *this; }
    insert_iterator<Container>& operator++() { return *this; }
    insert_iterator<Container> operator++(int) { return *this; }
  };

  template <class Container, class Iterator> _UCXXEXPORT insert_iterator<Container>
    inserter(Container& x, Iterator i)
  {
    return insert_iterator<Container>(x,typename Container::iterator(i));
  }

} // namespace
} // extern "C++"

#pragma GCC visibility pop
#endif // __STD_HEADER_ITERATOR_BASE
