/**
 * Licensed to the University Corporation for Advanced Internet
 * Development, Inc. (UCAID) under one or more contributor license
 * agreements. See the NOTICE file distributed with this work for
 * additional information regarding copyright ownership.
 *
 * UCAID licenses this file to you under the Apache License,
 * Version 2.0 (the "License"); you may not use this file except
 * in compliance with the License. You may obtain a copy of the
 * License at
 *
 * http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing,
 * software distributed under the License is distributed on an
 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND,
 * either express or implied. See the License for the specific
 * language governing permissions and limitations under the License.
 */

/**
 * @file xmltooling/char_traits.h
 *
 * Traits template for basic_string<unsigned short> instantiation on strict compilers.
 */

#ifndef __xmltooling_chartraits_h__
#define __xmltooling_chartraits_h__

#include <xmltooling/base.h>

#include <cstring>
#include <algorithm>

namespace xmltooling {

  /// @cond OFF

  template <class _CharT>
    struct _Char_types
    {
      typedef unsigned long   int_type;
      typedef std::streampos  pos_type;
      typedef std::streamoff  off_type;
      typedef std::mbstate_t  state_type;
    };


  template<typename _CharT>
    struct char_traits
    {
      typedef _CharT                                    char_type;
      typedef typename _Char_types<_CharT>::int_type    int_type;
      typedef typename _Char_types<_CharT>::pos_type    pos_type;
      typedef typename _Char_types<_CharT>::off_type    off_type;
      typedef typename _Char_types<_CharT>::state_type  state_type;

      static void
      assign(char_type& __c1, const char_type& __c2)
      { __c1 = __c2; }

      static bool
      eq(const char_type& __c1, const char_type& __c2)
      { return __c1 == __c2; }

      static bool
      lt(const char_type& __c1, const char_type& __c2)
      { return __c1 < __c2; }

      static int
      compare(const char_type* __s1, const char_type* __s2, std::size_t __n);

      static std::size_t
      length(const char_type* __s);

      static const char_type*
      find(const char_type* __s, std::size_t __n, const char_type& __a);

      static char_type*
      move(char_type* __s1, const char_type* __s2, std::size_t __n);

      static char_type*
      copy(char_type* __s1, const char_type* __s2, std::size_t __n);

      static char_type*
      assign(char_type* __s, std::size_t __n, char_type __a);

      static char_type
      to_char_type(const int_type& __c)
      { return static_cast<char_type>(__c); }

      static int_type
      to_int_type(const char_type& __c)
      { return static_cast<int_type>(__c); }

      static bool
      eq_int_type(const int_type& __c1, const int_type& __c2)
      { return __c1 == __c2; }

      static int_type
      eof()
      { return static_cast<int_type>(EOF); }

      static int_type
      not_eof(const int_type& __c)
      { return !eq_int_type(__c, eof()) ? __c : to_int_type(char_type()); }
    };

  template<typename _CharT>
    int
    char_traits<_CharT>::
    compare(const char_type* __s1, const char_type* __s2, std::size_t __n)
    {
      for (size_t __i = 0; __i < __n; ++__i)
    if (lt(__s1[__i], __s2[__i]))
      return -1;
    else if (lt(__s2[__i], __s1[__i]))
      return 1;
      return 0;
    }

  template<typename _CharT>
    std::size_t
    char_traits<_CharT>::
    length(const char_type* __p)
    {
      std::size_t __i = 0;
      while (!eq(__p[__i], char_type()))
        ++__i;
      return __i;
    }

  template<typename _CharT>
    const typename char_traits<_CharT>::char_type*
    char_traits<_CharT>::
    find(const char_type* __s, std::size_t __n, const char_type& __a)
    {
      for (std::size_t __i = 0; __i < __n; ++__i)
        if (eq(__s[__i], __a))
          return __s + __i;
      return 0;
    }

  template<typename _CharT>
    typename char_traits<_CharT>::char_type*
    char_traits<_CharT>::
    move(char_type* __s1, const char_type* __s2, std::size_t __n)
    {
      return static_cast<_CharT*>(std::memmove(__s1, __s2,
                           __n * sizeof(char_type)));
    }

  template<typename _CharT>
    typename char_traits<_CharT>::char_type*
    char_traits<_CharT>::
    copy(char_type* __s1, const char_type* __s2, std::size_t __n)
    {
      std::copy(__s2, __s2 + __n, __s1);
      return __s1;
    }

  template<typename _CharT>
    typename char_traits<_CharT>::char_type*
    char_traits<_CharT>::
    assign(char_type* __s, std::size_t __n, char_type __a)
    {
      std::fill_n(__s, __n, __a);
      return __s;
    }

    /// @endcond
}

#endif // __xmltooling_chartraits_h__