// <forward_list> -*- C++ -*-

// Copyright (C) 2010 Free Software Foundation, Inc.
//
// This file is part of the GNU ISO C++ Library.  This library is free
// software; you can redistribute it and/or modify it under the
// terms of the GNU General Public License as published by the
// Free Software Foundation; either version 3, 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 General Public License for more details.

// Under Section 7 of GPL version 3, you are granted additional
// permissions described in the GCC Runtime Library Exception, version
// 3.1, as published by the Free Software Foundation.

// You should have received a copy of the GNU General Public License and
// a copy of the GCC Runtime Library Exception along with this program;
// see the files COPYING3 and COPYING.RUNTIME respectively.  If not, see
// <http://www.gnu.org/licenses/>.

/** @file debug/forward_list
 *  This file is a GNU debug extension to the Standard C++ Library.
 */

#ifndef _GLIBCXX_DEBUG_FORWARD_LIST
#define _GLIBCXX_DEBUG_FORWARD_LIST 1

#pragma GCC system_header

#include <forward_list>
#include <debug/safe_sequence.h>
#include <debug/safe_iterator.h>

namespace std
{
namespace __debug
{
  /// Class std::forward_list with safety/checking/debug instrumentation.
  template<typename _Tp, typename _Alloc = std::allocator<_Tp> >
    class forward_list
    : public _GLIBCXX_STD_D::forward_list<_Tp, _Alloc>,
      public __gnu_debug::_Safe_sequence<forward_list<_Tp, _Alloc> >
    {
      typedef _GLIBCXX_STD_D::forward_list<_Tp, _Alloc> _Base;
      typedef __gnu_debug::_Safe_sequence<forward_list> _Safe_base;

    public:
      typedef typename _Base::reference             reference;
      typedef typename _Base::const_reference       const_reference;

      typedef __gnu_debug::_Safe_iterator<typename _Base::iterator,
					  forward_list> iterator;
      typedef __gnu_debug::_Safe_iterator<typename _Base::const_iterator,
					  forward_list> const_iterator;

      typedef typename _Base::size_type             size_type;
      typedef typename _Base::difference_type       difference_type;

      typedef _Tp                                   value_type;
      typedef _Alloc                                allocator_type;
      typedef typename _Base::pointer               pointer;
      typedef typename _Base::const_pointer         const_pointer;

      // 23.2.3.1 construct/copy/destroy:
      explicit
      forward_list(const _Alloc& __al = _Alloc())
      : _Base(__al) { }

      forward_list(const forward_list& __list, const _Alloc& __al)
      : _Base(__list, __al)
      { }

      forward_list(forward_list&& __list, const _Alloc& __al)
      : _Base(std::move(__list), __al)
      {
	this->_M_swap(__list);
      }

      explicit
      forward_list(size_type __n)
      : _Base(__n)
      { }

      forward_list(size_type __n, const _Tp& __value,
                   const _Alloc& __al = _Alloc())
      : _Base(__n, __value, __al)
      { }

      template<typename _InputIterator>
        forward_list(_InputIterator __first, _InputIterator __last,
                     const _Alloc& __al = _Alloc())
        : _Base(__gnu_debug::__base(__gnu_debug::__check_valid_range(__first,
								     __last)),
		__gnu_debug::__base(__last), __al)
        { }

      forward_list(const forward_list& __list)
      : _Base(__list)
      { }

      forward_list(forward_list&& __list)
      : _Base(std::move(__list)) { }

      forward_list(std::initializer_list<_Tp> __il,
                   const _Alloc& __al = _Alloc())
      : _Base(__il, __al)
      { }

      ~forward_list()
      { }

      forward_list&
      operator=(const forward_list& __list)
      {
	static_cast<_Base&>(*this) = __list;
	this->_M_invalidate_all();
	return *this;
      }

      forward_list&
      operator=(forward_list&& __list)
      {
	// NB: DR 1204.
	// NB: DR 675.
	clear();
	swap(__list);
	return *this;
      }

      forward_list&
      operator=(std::initializer_list<_Tp> __il)
      {
	static_cast<_Base&>(*this) = __il;
	this->_M_invalidate_all();
        return *this;
      }

      template<typename _InputIterator>
        void
        assign(_InputIterator __first, _InputIterator __last)
        {
	  __glibcxx_check_valid_range(__first, __last);
	  _Base::assign(__gnu_debug::__base(__first),
			__gnu_debug::__base(__last));
	  this->_M_invalidate_all();
        }

      void
      assign(size_type __n, const _Tp& __val)
      {
	_Base::assign(__n, __val);
	this->_M_invalidate_all();
      }

      void
      assign(std::initializer_list<_Tp> __il)
      {
	_Base::assign(__il);
	this->_M_invalidate_all();
      }

      using _Base::get_allocator;

      // iterators:

      iterator
      before_begin()
      { return iterator(_Base::before_begin(), this); }

      const_iterator
      before_begin() const
      { return const_iterator(_Base::before_begin(), this); }

      iterator
      begin()
      { return iterator(_Base::begin(), this); }

      const_iterator
      begin() const
      { return const_iterator(_Base::begin(), this); }

      iterator
      end()
      { return iterator(_Base::end(), this); }

      const_iterator
      end() const
      { return const_iterator(_Base::end(), this); }

      const_iterator
      cbegin() const
      { return const_iterator(_Base::cbegin(), this); }

      const_iterator
      cbefore_begin() const
      { return const_iterator(_Base::cbefore_begin(), this); }

      const_iterator
      cend() const
      { return const_iterator(_Base::cend(), this); }

      using _Base::empty;
      using _Base::max_size;

      // element access:

      reference
      front()
      {
	__glibcxx_check_nonempty();
	return _Base::front();
      }

      const_reference
      front() const
      {
	__glibcxx_check_nonempty();
	return _Base::front();
      }

      // modiﬁers:

      using _Base::emplace_front;
      using _Base::push_front;

      void
      pop_front()
      {
	__glibcxx_check_nonempty();
	iterator __victim = begin();
	__victim._M_invalidate();
	_Base::pop_front();
      }

      template<typename... _Args>
	iterator
	emplace_after(const_iterator __pos, _Args&&... __args)
	{
	  __glibcxx_check_insert_after(__pos);
	  return iterator(_Base::emplace_after(__pos.base(),
					std::forward<_Args>(__args)...),
			  this);
       	}

      iterator
      insert_after(const_iterator __pos, const _Tp& __val)
      {
	__glibcxx_check_insert_after(__pos);
	return iterator(_Base::insert_after(__pos.base(), __val), this);
      }

      iterator
      insert_after(const_iterator __pos, _Tp&& __val)
      {
	__glibcxx_check_insert_after(__pos);
	return iterator(_Base::insert_after(__pos.base(), std::move(__val)),
		       	this);
      }

      iterator
      insert_after(const_iterator __pos, size_type __n, const _Tp& __val)
      {
	__glibcxx_check_insert_after(__pos);
	return iterator(_Base::insert_after(__pos.base(), __n, __val),
		       	this);
      }

      template<typename _InputIterator>
        iterator
        insert_after(const_iterator __pos,
                     _InputIterator __first, _InputIterator __last)
        {
	  __glibcxx_check_insert_range_after(__pos, __first, __last);
	  return iterator(_Base::insert_after(__pos.base(),
					      __gnu_debug::__base(__first),
					      __gnu_debug::__base(__last)),
			  this);
        }

      iterator
      insert_after(const_iterator __pos, std::initializer_list<_Tp> __il)
      {
	__glibcxx_check_insert_after(__pos);
	return iterator(_Base::insert_after(__pos.base(), __il), this);
      }

      void
      erase_after(const_iterator __pos)
      {
	__glibcxx_check_erase_after(__pos);
	const_iterator __victim = __pos;
	++__victim;
	__victim._M_invalidate();
	_Base::erase_after(__pos.base());
      }

      void
      erase_after(const_iterator __pos, const_iterator __last)
      {
	__glibcxx_check_erase_range_after(__pos, __last);
	for (const_iterator __victim = std::next(__pos); __victim != __last; )
	  {
	    const_iterator __old = __victim++;
	    __old._M_invalidate();
	  }
	_Base::erase_after(__pos.base(), __last.base());
      }

      void
      swap(forward_list& __list)
      {
	_Base::swap(__list);
	this->_M_swap(__list);
      }

      void
      resize(size_type __sz)
      {
	this->_M_detach_singular();

	// if __sz < size(), invalidate all iterators in [begin+__sz, end()
	iterator __victim = begin();
	iterator __end = end();
	for (size_type __i = __sz; __victim != __end && __i > 0; --__i)
	  ++__victim;

	while (__victim != __end)
	  {
	    iterator __real_victim = __victim++;
	    __real_victim._M_invalidate();
	  }

	__try
	  {
	    _Base::resize(__sz);
	  }
	__catch(...)
	  {
	    this->_M_revalidate_singular();
	    __throw_exception_again;
          }
      }

      void
      resize(size_type __sz, const value_type& __val)
      {
	this->_M_detach_singular();

	// if __sz < size(), invalidate all iterators in [begin+__sz, end())
	iterator __victim = begin();
	iterator __end = end();
	for (size_type __i = __sz; __victim != __end && __i > 0; --__i)
	  ++__victim;

	while (__victim != __end)
	  {
	    iterator __real_victim = __victim++;
	    __real_victim._M_invalidate();
	  }

	__try
	  {
	    _Base::resize(__sz, __val);
	  }
	__catch(...)
	  {
	    this->_M_revalidate_singular();
	    __throw_exception_again;
          }
      }

      void
      clear()
      {
	_Base::clear();
	this->_M_invalidate_all();
      }

      // 23.2.3.5 forward_list operations:
    private:
      void
      _M_splice_after(const_iterator __pos, forward_list&& __list,
		      const_iterator __before, const_iterator __last)
      {
	for (const_iterator __tmp = std::next(__before); __tmp != __last; )
	  {
	    _GLIBCXX_DEBUG_VERIFY(&__list != this || __tmp != __pos,
                                  _M_message(__gnu_debug::__msg_splice_overlap)
                                  ._M_iterator(__tmp, "position")
				  ._M_iterator(__before, "before")
				  ._M_iterator(__last, "last"));
	    const_iterator __victim = __tmp++;
	    // _GLIBCXX_RESOLVE_LIB_DEFECTS
	    // 250. splicing invalidates iterators
	    this->_M_transfer_iter(__victim);
	  }

	_Base::splice_after(__pos.base(), std::move(__list._M_base()),
			    __before.base(), __last.base());
      }

    public:
      void
      splice_after(const_iterator __pos, forward_list&& __list)
      {
        __glibcxx_check_insert_after(__pos);
	_GLIBCXX_DEBUG_VERIFY(&__list != this,
			      _M_message(__gnu_debug::__msg_self_splice)
			      ._M_sequence(*this, "this"));
	_M_splice_after(__pos, std::move(__list),
			__list.before_begin(), __list.end());
      }

      void
      splice_after(const_iterator __pos, forward_list&& __list,
		   const_iterator __i)
      {
	__glibcxx_check_insert_after(__pos);
	_GLIBCXX_DEBUG_VERIFY(__i._M_before_dereferenceable(),
			      _M_message(__gnu_debug::__msg_splice_bad)
			      ._M_iterator(__i, "__i"));
	_GLIBCXX_DEBUG_VERIFY(__i._M_attached_to(&__list),
			      _M_message(__gnu_debug::__msg_splice_other)
			      ._M_iterator(__i, "__i")
			      ._M_sequence(__list, "__list"));

	// _GLIBCXX_RESOLVE_LIB_DEFECTS
	// 250. splicing invalidates iterators
	this->_M_transfer_iter(__i);
	_Base::splice_after(__pos.base(), std::move(__list._M_base()),
			    __i.base());
      }

      void
      splice_after(const_iterator __pos, forward_list&& __list,
		   const_iterator __before, const_iterator __last)
      {
        __glibcxx_check_insert_after(__pos);
	__glibcxx_check_valid_range(__before, __last);
	_GLIBCXX_DEBUG_VERIFY(__before._M_attached_to(&__list),
			      _M_message(__gnu_debug::__msg_splice_other)
			      ._M_sequence(__list, "list")
			      ._M_iterator(__before, "before"));
	_GLIBCXX_DEBUG_VERIFY(__before._M_dereferenceable()
			      || __before._M_is_before_begin(),
			      _M_message(__gnu_debug::__msg_valid_range2)
			      ._M_sequence(__list, "list")
			      ._M_iterator(__before, "before")
			      ._M_iterator(__last, "last"));
	_GLIBCXX_DEBUG_VERIFY(__before != __last,
			      _M_message(__gnu_debug::__msg_valid_range2)
			      ._M_sequence(__list, "list")
			      ._M_iterator(__before, "before")
			      ._M_iterator(__last, "last"));
	_M_splice_after(__pos, std::move(__list), __before, __last);
      }

      void
      remove(const _Tp& __val)
      {
	iterator __x = before_begin();
	iterator __old = __x++;
	while (__x.base() != _Base::end())
	  {
	    if (*__x == __val)
	      {
		erase_after(__old);
		__x = __old; ++__x;
	      }
	    else
	      __old = __x++;
	  }
      }

      template<typename _Pred>
        void
        remove_if(_Pred __pred)
	{
	  iterator __x = before_begin();
	  iterator __old = __x++;
	  while (__x.base() != _Base::end())
	    {
	      if (__pred(*__x))
		{
		  erase_after(__old);
		  __x = std::next(__old);
		}
	      else
		__old = __x++;
	    }
	}

      void
      unique()
      {
	iterator __first = begin();
	iterator __last = end();
	if (__first == __last)
	  return;
	iterator __next = __first;
	while (++__next != __last)
	  {
	    if (*__first == *__next)
	      {
		erase_after(__first);
		__next = __first;
	      }
	    else
	      __first = __next;
	  }
      }

      template<typename _BinPred>
        void
        unique(_BinPred __binary_pred)
	{
	  iterator __first = begin();
	  iterator __last = end();
	  if (__first == __last)
	    return;
	  iterator __next = __first;
	  while (++__next != __last)
	    {
	      if (__binary_pred(*__first, *__next))
		{
		  erase_after(__first);
		  __next = __first;
		}
	      else
		__first = __next;
	    }
	}

      void
      merge(forward_list&& __list)
      {
	if (this != &__list)
	{
	  __glibcxx_check_sorted(_Base::begin(), _Base::end());
	  __glibcxx_check_sorted(__list._M_base().begin(),
				 __list._M_base().end());
	  for (iterator __tmp = __list.begin(); __tmp != __list.end();)
	    {
	      iterator __victim = __tmp++;
	      this->_M_transfer_iter(__victim);
	    }
	  _Base::merge(std::move(__list._M_base()));
	}
      }

      template<typename _Comp>
        void
        merge(forward_list&& __list, _Comp __comp)
	{
	  if (this != &__list)
	  {
	    __glibcxx_check_sorted_pred(_Base::begin(), _Base::end(), __comp);
	    __glibcxx_check_sorted_pred(__list._M_base().begin(),
					__list._M_base().end(), __comp);
	    for (iterator __tmp = __list.begin(); __tmp != __list.end();)
	      {
		iterator __victim = __tmp++;
		this->_M_transfer_iter(__victim);
	      }
	    _Base::merge(std::move(__list._M_base()), __comp);
	  }
	}

      using _Base::sort;
      using _Base::reverse;

      _Base&
      _M_base()       { return *this; }

      const _Base&
      _M_base() const { return *this; }

    private:
      void
      _M_invalidate_all()
      {
	typedef typename _Base::const_iterator _Base_const_iterator;
	typedef __gnu_debug::_Not_equal_to<_Base_const_iterator> _Not_equal;
	this->_M_invalidate_if(_Not_equal(_M_base().end()));
      }
    };

  template<typename _Tp, typename _Alloc>
    bool
    operator==(const forward_list<_Tp, _Alloc>& __lx,
               const forward_list<_Tp, _Alloc>& __ly)
    { return __lx._M_base() == __ly._M_base(); }

  template<typename _Tp, typename _Alloc>
    inline bool
    operator<(const forward_list<_Tp, _Alloc>& __lx,
              const forward_list<_Tp, _Alloc>& __ly)
    { return __lx._M_base() < __ly._M_base(); }

  template<typename _Tp, typename _Alloc>
    inline bool
    operator!=(const forward_list<_Tp, _Alloc>& __lx,
               const forward_list<_Tp, _Alloc>& __ly)
    { return !(__lx == __ly); }

  /// Based on operator<
  template<typename _Tp, typename _Alloc>
    inline bool
    operator>(const forward_list<_Tp, _Alloc>& __lx,
              const forward_list<_Tp, _Alloc>& __ly)
    { return (__ly < __lx); }

  /// Based on operator<
  template<typename _Tp, typename _Alloc>
    inline bool
    operator>=(const forward_list<_Tp, _Alloc>& __lx,
               const forward_list<_Tp, _Alloc>& __ly)
    { return !(__lx < __ly); }

  /// Based on operator<
  template<typename _Tp, typename _Alloc>
    inline bool
    operator<=(const forward_list<_Tp, _Alloc>& __lx,
               const forward_list<_Tp, _Alloc>& __ly)
    { return !(__ly < __lx); }

  /// See std::forward_list::swap().
  template<typename _Tp, typename _Alloc>
    inline void
    swap(forward_list<_Tp, _Alloc>& __lx,
	 forward_list<_Tp, _Alloc>& __ly)
    { __lx.swap(__ly); }

} // namespace __debug
} // namespace std

namespace __gnu_debug
{
  template<class _Tp, class _Alloc>
    struct _BeforeBeginHelper<std::__debug::forward_list<_Tp, _Alloc> >
    {
      typedef typename forward_list<_Tp, _Alloc>::const_iterator _It;

      static bool
      _M_Is(_It __it, const forward_list<_Tp, _Alloc>* __seq)
      { return __it == __seq->before_begin(); }
    };
}

#endif
