/*

 *

 * Copyright (c) 2004

 * John Maddock

 *

 * Use, modification and distribution are subject to the 

 * Boost Software License, Version 1.0. (See accompanying file 

 * LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)

 *

 */

 /*

  *   LOCATION:    see http://www.boost.org for most recent version.

  *   FILE         basic_regex_creator.cpp

  *   VERSION      see <boost/version.hpp>

  *   DESCRIPTION: Declares template class basic_regex_creator which fills in

  *                the data members of a regex_data object.

  */

#ifndef BOOST_REGEX_V4_BASIC_REGEX_CREATOR_HPP

#define BOOST_REGEX_V4_BASIC_REGEX_CREATOR_HPP

#ifdef BOOST_MSVC

#pragma warning(push)

#pragma warning(disable: 4103)

#endif

#ifdef BOOST_HAS_ABI_HEADERS

#  include BOOST_ABI_PREFIX

#endif

#ifdef BOOST_MSVC

#pragma warning(pop)

#endif

#ifdef BOOST_MSVC

#  pragma warning(push)

#  pragma warning(disable: 4800)

#endif

namespace boost{

namespace re_detail{

template <class charT>

struct digraph : public std::pair<charT, charT>

{

   digraph() : std::pair<charT, charT>(0, 0){}

   digraph(charT c1) : std::pair<charT, charT>(c1, 0){}

   digraph(charT c1, charT c2) : std::pair<charT, charT>(c1, c2)

   {}

#if !BOOST_WORKAROUND(BOOST_MSVC, < 1300)

   digraph(const digraph<charT>& d) : std::pair<charT, charT>(d.first, d.second){}

#endif

   template <class Seq>

   digraph(const Seq& s) : std::pair<charT, charT>()

   {

      BOOST_ASSERT(s.size() <= 2);

      BOOST_ASSERT(s.size());

      this->first = s[0];

      this->second = (s.size() > 1) ? s[1] : 0;

   }

};

template <class charT, class traits>

class basic_char_set

{

public:

   typedef digraph<charT>                   digraph_type;

   typedef typename traits::string_type     string_type;

   typedef typename traits::char_class_type mask_type;

   basic_char_set()

   {

      m_negate = false;

      m_has_digraphs = false;

      m_classes = 0;

      m_negated_classes = 0;

      m_empty = true;

   }

   void add_single(const digraph_type& s)

   {

      m_singles.insert(m_singles.end(), s);

      if(s.second)

         m_has_digraphs = true;

      m_empty = false;

   }

   void add_range(const digraph_type& first, const digraph_type& end)

   {

      m_ranges.insert(m_ranges.end(), first);

      m_ranges.insert(m_ranges.end(), end);

      if(first.second)

      {

         m_has_digraphs = true;

         add_single(first);

      }

      if(end.second)

      {

         m_has_digraphs = true;

         add_single(end);

      }

      m_empty = false;

   }

   void add_class(mask_type m)

   {

      m_classes |= m;

      m_empty = false;

   }

   void add_negated_class(mask_type m)

   {

      m_negated_classes |= m;

      m_empty = false;

   }

   void add_equivalent(const digraph_type& s)

   {

      m_equivalents.insert(m_equivalents.end(), s);

      if(s.second)

      {

         m_has_digraphs = true;

         add_single(s);

      }

      m_empty = false;

   }

   void negate()

   { 

      m_negate = true;

      //m_empty = false;

   }

   //

   // accessor functions:

   //

   bool has_digraphs()const

   {

      return m_has_digraphs;

   }

   bool is_negated()const

   {

      return m_negate;

   }

   typedef typename std::vector<digraph_type>::const_iterator  list_iterator;

   list_iterator singles_begin()const

   {

      return m_singles.begin();

   }

   list_iterator singles_end()const

   {

      return m_singles.end();

   }

   list_iterator ranges_begin()const

   {

      return m_ranges.begin();

   }

   list_iterator ranges_end()const

   {

      return m_ranges.end();

   }

   list_iterator equivalents_begin()const

   {

      return m_equivalents.begin();

   }

   list_iterator equivalents_end()const

   {

      return m_equivalents.end();

   }

   mask_type classes()const

   {

      return m_classes;

   }

   mask_type negated_classes()const

   {

      return m_negated_classes;

   }

   bool empty()const

   {

      return m_empty;

   }

private:

   std::vector<digraph_type> m_singles;         // a list of single characters to match

   std::vector<digraph_type> m_ranges;          // a list of end points of our ranges

   bool                      m_negate;          // true if the set is to be negated

   bool                      m_has_digraphs;    // true if we have digraphs present

   mask_type                 m_classes;         // character classes to match

   mask_type                 m_negated_classes; // negated character classes to match

   bool                      m_empty;           // whether we've added anything yet

   std::vector<digraph_type> m_equivalents;     // a list of equivalence classes

};

template <class charT, class traits>

class basic_regex_creator

{

public:

   basic_regex_creator(regex_data<charT, traits>* data);

   std::ptrdiff_t getoffset(void* addr)

   {

      return getoffset(addr, m_pdata->m_data.data());

   }

   std::ptrdiff_t getoffset(const void* addr, const void* base)

   {

      return static_cast<const char*>(addr) - static_cast<const char*>(base);

   }

   re_syntax_base* getaddress(std::ptrdiff_t off)

   {

      return getaddress(off, m_pdata->m_data.data());

   }

   re_syntax_base* getaddress(std::ptrdiff_t off, void* base)

   {

      return static_cast<re_syntax_base*>(static_cast<void*>(static_cast<char*>(base) + off));

   }

   void init(unsigned l_flags)

   {

      m_pdata->m_flags = l_flags;

      m_icase = l_flags & regex_constants::icase;

   }

   regbase::flag_type flags()

   {

      return m_pdata->m_flags;

   }

   void flags(regbase::flag_type f)

   {

      m_pdata->m_flags = f;

      if(m_icase != static_cast<bool>(f & regbase::icase))

      {

         m_icase = static_cast<bool>(f & regbase::icase);

      }

   }

   re_syntax_base* append_state(syntax_element_type t, std::size_t s = sizeof(re_syntax_base));

   re_syntax_base* insert_state(std::ptrdiff_t pos, syntax_element_type t, std::size_t s = sizeof(re_syntax_base));

   re_literal* append_literal(charT c);

   re_syntax_base* append_set(const basic_char_set<charT, traits>& char_set);

   re_syntax_base* append_set(const basic_char_set<charT, traits>& char_set, mpl::false_*);

   re_syntax_base* append_set(const basic_char_set<charT, traits>& char_set, mpl::true_*);

   void finalize(const charT* p1, const charT* p2);

protected:

   regex_data<charT, traits>*    m_pdata;              // pointer to the basic_regex_data struct we are filling in

   const ::boost::regex_traits_wrapper<traits>&  

                                 m_traits;             // convenience reference to traits class

   re_syntax_base*               m_last_state;         // the last state we added

   bool                          m_icase;              // true for case insensitive matches

   unsigned                      m_repeater_id;        // the state_id of the next repeater

   bool                          m_has_backrefs;       // true if there are actually any backrefs

   unsigned                      m_backrefs;           // bitmask of permitted backrefs

   boost::uintmax_t              m_bad_repeats;        // bitmask of repeats we can't deduce a startmap for;

   typename traits::char_class_type m_word_mask;       // mask used to determine if a character is a word character

   typename traits::char_class_type m_mask_space;      // mask used to determine if a character is a word character

   typename traits::char_class_type m_lower_mask;       // mask used to determine if a character is a lowercase character

   typename traits::char_class_type m_upper_mask;      // mask used to determine if a character is an uppercase character

   typename traits::char_class_type m_alpha_mask;      // mask used to determine if a character is an alphabetic character

private:

   basic_regex_creator& operator=(const basic_regex_creator&);

   basic_regex_creator(const basic_regex_creator&);

   void fixup_pointers(re_syntax_base* state);

   void create_startmaps(re_syntax_base* state);

   int calculate_backstep(re_syntax_base* state);

   void create_startmap(re_syntax_base* state, unsigned char* l_map, unsigned int* pnull, unsigned char mask);

   unsigned get_restart_type(re_syntax_base* state);

   void set_all_masks(unsigned char* bits, unsigned char);

   bool is_bad_repeat(re_syntax_base* pt);

   void set_bad_repeat(re_syntax_base* pt);

   syntax_element_type get_repeat_type(re_syntax_base* state);

   void probe_leading_repeat(re_syntax_base* state);

};

template <class charT, class traits>

basic_regex_creator<charT, traits>::basic_regex_creator(regex_data<charT, traits>* data)

   : m_pdata(data), m_traits(*(data->m_ptraits)), m_last_state(0), m_repeater_id(0), m_has_backrefs(false), m_backrefs(0)

{

   m_pdata->m_data.clear();

   m_pdata->m_status = ::boost::regex_constants::error_ok;

   static const charT w = 'w';

   static const charT s = 's';

   static const charT l[5] = { 'l', 'o', 'w', 'e', 'r', };

   static const charT u[5] = { 'u', 'p', 'p', 'e', 'r', };

   static const charT a[5] = { 'a', 'l', 'p', 'h', 'a', };

   m_word_mask = m_traits.lookup_classname(&w, &w +1);

   m_mask_space = m_traits.lookup_classname(&s, &s +1);

   m_lower_mask = m_traits.lookup_classname(l, l + 5);

   m_upper_mask = m_traits.lookup_classname(u, u + 5);

   m_alpha_mask = m_traits.lookup_classname(a, a + 5);

   m_pdata->m_word_mask = m_word_mask;

   BOOST_ASSERT(m_word_mask != 0); 

   BOOST_ASSERT(m_mask_space != 0); 

   BOOST_ASSERT(m_lower_mask != 0); 

   BOOST_ASSERT(m_upper_mask != 0); 

   BOOST_ASSERT(m_alpha_mask != 0); 

}

template <class charT, class traits>

re_syntax_base* basic_regex_creator<charT, traits>::append_state(syntax_element_type t, std::size_t s)

{

   // if the state is a backref then make a note of it:

   if(t == syntax_element_backref)

      this->m_has_backrefs = true;

   // append a new state, start by aligning our last one:

   m_pdata->m_data.align();

   // set the offset to the next state in our last one:

   if(m_last_state)

      m_last_state->next.i = m_pdata->m_data.size() - getoffset(m_last_state);

   // now actually extent our data:

   m_last_state = static_cast<re_syntax_base*>(m_pdata->m_data.extend(s));

   // fill in boilerplate options in the new state:

   m_last_state->next.i = 0;

   m_last_state->type = t;

   return m_last_state;

}

template <class charT, class traits>

re_syntax_base* basic_regex_creator<charT, traits>::insert_state(std::ptrdiff_t pos, syntax_element_type t, std::size_t s)

{

   // append a new state, start by aligning our last one:

   m_pdata->m_data.align();

   // set the offset to the next state in our last one:

   if(m_last_state)

      m_last_state->next.i = m_pdata->m_data.size() - getoffset(m_last_state);

   // remember the last state position:

   std::ptrdiff_t off = getoffset(m_last_state) + s;

   // now actually insert our data:

   re_syntax_base* new_state = static_cast<re_syntax_base*>(m_pdata->m_data.insert(pos, s));

   // fill in boilerplate options in the new state:

   new_state->next.i = s;

   new_state->type = t;

   m_last_state = getaddress(off);

   return new_state;

}

template <class charT, class traits>

re_literal* basic_regex_creator<charT, traits>::append_literal(charT c)

{

   re_literal* result;

   // start by seeing if we have an existing re_literal we can extend:

   if((0 == m_last_state) || (m_last_state->type != syntax_element_literal))

   {

      // no existing re_literal, create a new one:

      result = static_cast<re_literal*>(append_state(syntax_element_literal, sizeof(re_literal) + sizeof(charT)));

      result->length = 1;

      *static_cast<charT*>(static_cast<void*>(result+1)) = m_traits.translate(c, m_icase);

   }

   else

   {

      // we have an existing re_literal, extend it:

      std::ptrdiff_t off = getoffset(m_last_state);

      m_pdata->m_data.extend(sizeof(charT));

      m_last_state = result = static_cast<re_literal*>(getaddress(off));

      charT* characters = static_cast<charT*>(static_cast<void*>(result+1));

      characters[result->length] = m_traits.translate(c, m_icase);

      ++(result->length);

   }

   return result;

}

template <class charT, class traits>

inline re_syntax_base* basic_regex_creator<charT, traits>::append_set(

   const basic_char_set<charT, traits>& char_set)

{

   typedef mpl::bool_< (sizeof(charT) == 1) > truth_type;

   return char_set.has_digraphs() 

      ? append_set(char_set, static_cast<mpl::false_*>(0))

      : append_set(char_set, static_cast<truth_type*>(0));

}

template <class charT, class traits>

re_syntax_base* basic_regex_creator<charT, traits>::append_set(

   const basic_char_set<charT, traits>& char_set, mpl::false_*)

{

   typedef typename traits::string_type string_type;

   typedef typename basic_char_set<charT, traits>::list_iterator item_iterator;

   typedef typename traits::char_class_type mask_type;

   re_set_long<mask_type>* result = static_cast<re_set_long<mask_type>*>(append_state(syntax_element_long_set, sizeof(re_set_long<mask_type>)));

   //

   // fill in the basics:

   //

   result->csingles = static_cast<unsigned int>(::boost::re_detail::distance(char_set.singles_begin(), char_set.singles_end()));

   result->cranges = static_cast<unsigned int>(::boost::re_detail::distance(char_set.ranges_begin(), char_set.ranges_end())) / 2;

   result->cequivalents = static_cast<unsigned int>(::boost::re_detail::distance(char_set.equivalents_begin(), char_set.equivalents_end()));

   result->cclasses = char_set.classes();

   result->cnclasses = char_set.negated_classes();

   if(flags() & regbase::icase)

   {

      // adjust classes as needed:

      if(((result->cclasses & m_lower_mask) == m_lower_mask) || ((result->cclasses & m_upper_mask) == m_upper_mask))

         result->cclasses |= m_alpha_mask;

      if(((result->cnclasses & m_lower_mask) == m_lower_mask) || ((result->cnclasses & m_upper_mask) == m_upper_mask))

         result->cnclasses |= m_alpha_mask;

   }

   result->isnot = char_set.is_negated();

   result->singleton = !char_set.has_digraphs();

   //

   // remember where the state is for later:

   //

   std::ptrdiff_t offset = getoffset(result);

   //

   // now extend with all the singles:

   //

   item_iterator first, last;

   first = char_set.singles_begin();

   last = char_set.singles_end();

   while(first != last)

   {

      charT* p = static_cast<charT*>(this->m_pdata->m_data.extend(sizeof(charT) * (first->second ? 3 : 2)));

      p[0] = m_traits.translate(first->first, m_icase);

      if(first->second)

      {

         p[1] = m_traits.translate(first->second, m_icase);

         p[2] = 0;

      }

      else

         p[1] = 0;

      ++first;

   }

   //

   // now extend with all the ranges:

   //

   first = char_set.ranges_begin();

   last = char_set.ranges_end();

   while(first != last)

   {

      // first grab the endpoints of the range:

      digraph<charT> c1 = *first;

      c1.first = this->m_traits.translate(c1.first, this->m_icase);

      c1.second = this->m_traits.translate(c1.second, this->m_icase);

      ++first;

      digraph<charT> c2 = *first;

      c2.first = this->m_traits.translate(c2.first, this->m_icase);

      c2.second = this->m_traits.translate(c2.second, this->m_icase);

      ++first;

      string_type s1, s2;

      // different actions now depending upon whether collation is turned on:

      if(flags() & regex_constants::collate)

      {

         // we need to transform our range into sort keys:

#if BOOST_WORKAROUND(__GNUC__, < 3)

         string_type in(3, charT(0));

         in[0] = c1.first;

         in[1] = c1.second;

         s1 = this->m_traits.transform(in.c_str(), (in[1] ? in.c_str()+2 : in.c_str()+1));

         in[0] = c2.first;

         in[1] = c2.second;

         s2 = this->m_traits.transform(in.c_str(), (in[1] ? in.c_str()+2 : in.c_str()+1));

#else

         charT a1[3] = { c1.first, c1.second, charT(0), };

         charT a2[3] = { c2.first, c2.second, charT(0), };

         s1 = this->m_traits.transform(a1, (a1[1] ? a1+2 : a1+1));

         s2 = this->m_traits.transform(a2, (a2[1] ? a2+2 : a2+1));

#endif

         if(s1.size() == 0)

            s1 = string_type(1, charT(0));

         if(s2.size() == 0)

            s2 = string_type(1, charT(0));

      }

      else

      {

         if(c1.second)

         {

            s1.insert(s1.end(), c1.first);

            s1.insert(s1.end(), c1.second);

         }

         else

            s1 = string_type(1, c1.first);

         if(c2.second)

         {

            s2.insert(s2.end(), c2.first);

            s2.insert(s2.end(), c2.second);

         }

         else

            s2.insert(s2.end(), c2.first);

      }

      if(s1 > s2)

      {

         // Oops error:

         return 0;

      }

      charT* p = static_cast<charT*>(this->m_pdata->m_data.extend(sizeof(charT) * (s1.size() + s2.size() + 2) ) );

      re_detail::copy(s1.begin(), s1.end(), p);

      p[s1.size()] = charT(0);

      p += s1.size() + 1;

      re_detail::copy(s2.begin(), s2.end(), p);

      p[s2.size()] = charT(0);

   }

   //

   // now process the equivalence classes:

   //

   first = char_set.equivalents_begin();

   last = char_set.equivalents_end();

   while(first != last)

   {

      string_type s;

      if(first->second)

      {

#if BOOST_WORKAROUND(__GNUC__, < 3)

         string_type in(3, charT(0));

         in[0] = first->first;

         in[1] = first->second;

         s = m_traits.transform_primary(in.c_str(), in.c_str()+2);

#else

         charT cs[3] = { first->first, first->second, charT(0), };

         s = m_traits.transform_primary(cs, cs+2);

#endif

      }

      else

         s = m_traits.transform_primary(&first->first, &first->first+1);

      if(s.empty())

         return 0;  // invalid or unsupported equivalence class

      charT* p = static_cast<charT*>(this->m_pdata->m_data.extend(sizeof(charT) * (s.size()+1) ) );

      re_detail::copy(s.begin(), s.end(), p);

      p[s.size()] = charT(0);

      ++first;

   }

   //

   // finally reset the address of our last state:

   //

   m_last_state = result = static_cast<re_set_long<mask_type>*>(getaddress(offset));

   return result;

}

namespace{

template<class T>

inline bool char_less(T t1, T t2)

{

   return t1 < t2;

}

template<>

inline bool char_less<char>(char t1, char t2)

{

   return static_cast<unsigned char>(t1) < static_cast<unsigned char>(t2);

}

template<>