// class template regex -*- C++ -*-

// Copyright (C) 2013 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 bits/regex_automaton.tcc
 *  This is an internal header file, included by other library headers.
 *  Do not attempt to use it directly. @headername{regex}
 */

namespace std _GLIBCXX_VISIBILITY(default)
{
namespace __detail
{
_GLIBCXX_BEGIN_NAMESPACE_VERSION

#ifdef _GLIBCXX_DEBUG
  template<typename _CharT, typename _TraitsT>
    std::ostream& _State<_CharT, _TraitsT>::
    _M_print(std::ostream& ostr) const
    {
      switch (_M_opcode)
      {
	case _S_opcode_alternative:
	  ostr << "alt next=" << _M_next << " alt=" << _M_alt;
	  break;
	case _S_opcode_subexpr_begin:
	  ostr << "subexpr begin next=" << _M_next << " index=" << _M_subexpr;
	  break;
	case _S_opcode_subexpr_end:
	  ostr << "subexpr end next=" << _M_next << " index=" << _M_subexpr;
	  break;
	case _S_opcode_backref:
	  ostr << "backref next=" << _M_next << " index=" << _M_backref_index;
	  break;
	case _S_opcode_match:
	  ostr << "match next=" << _M_next;
	  break;
	case _S_opcode_accept:
	  ostr << "accept next=" << _M_next;
	  break;
	default:
	  ostr << "unknown next=" << _M_next;
	  break;
      }
      return ostr;
    }

  // Prints graphviz dot commands for state.
  template<typename _CharT, typename _TraitsT>
    std::ostream& _State<_CharT, _TraitsT>::
    _M_dot(std::ostream& __ostr, _StateIdT __id) const
    {
      switch (_M_opcode)
      {
	case _S_opcode_alternative:
	  __ostr << __id << " [label=\"" << __id << "\\nALT\"];\n"
		 << __id << " -> " << _M_next
		 << " [label=\"epsilon\", tailport=\"s\"];\n"
		 << __id << " -> " << _M_alt
		 << " [label=\"epsilon\", tailport=\"n\"];\n";
	  break;
	case _S_opcode_subexpr_begin:
	  __ostr << __id << " [label=\"" << __id << "\\nSBEGIN "
		 << _M_subexpr << "\"];\n"
		 << __id << " -> " << _M_next << " [label=\"epsilon\"];\n";
	  break;
	case _S_opcode_subexpr_end:
	  __ostr << __id << " [label=\"" << __id << "\\nSEND "
		 << _M_subexpr << "\"];\n"
		 << __id << " -> " << _M_next << " [label=\"epsilon\"];\n";
	  break;
	case _S_opcode_backref:
	  __ostr << __id << " [label=\"" << __id << "\\nBACKREF "
		 << _M_subexpr << "\"];\n"
		 << __id << " -> " << _M_next << " [label=\"<match>\"];\n";
	  break;
	case _S_opcode_match:
	  __ostr << __id << " [label=\"" << __id << "\\nMATCH\"];\n"
		 << __id << " -> " << _M_next << " [label=\"<match>\"];\n";
	  break;
	case _S_opcode_accept:
	  __ostr << __id << " [label=\"" << __id << "\\nACC\"];\n" ;
	  break;
	default:
	  __ostr << __id << " [label=\"" << __id << "\\nUNK\"];\n"
		 << __id << " -> " << _M_next << " [label=\"?\"];\n";
	  break;
      }
      return __ostr;
    }

  template<typename _CharT, typename _TraitsT>
    std::ostream& _NFA<_CharT, _TraitsT>::
    _M_dot(std::ostream& __ostr) const
    {
      __ostr << "digraph _Nfa {\n"
       << "  rankdir=LR;\n";
      for (unsigned int __i = 0; __i < this->size(); ++__i)
      { this->at(__i)._M_dot(__ostr, __i); }
      __ostr << "}\n";
      return __ostr;
    }
#endif

  template<typename _CharT, typename _TraitsT>
    _StateIdT _NFA<_CharT, _TraitsT>::
    _M_insert_backref(unsigned int __index)
    {
      // To figure out whether a backref is valid, a stack is used to store
      // unfinished sub-expressions. For example, when parsing
      // "(a(b)(c\\1(d)))" at '\\1', _M_subexpr_count is 3, indicating that 3
      // sub expressions are parsed or partially parsed(in the stack), aka,
      // "(a..", "(b)" and "(c..").
      // _M_paren_stack is {1, 3}, for incomplete "(a.." and "(c..". At this
      // time, "\\2" is valid, but "\\1" and "\\3" are not.
      if (__index >= _M_subexpr_count)
	__throw_regex_error(regex_constants::error_backref);
      for (auto __it : _M_paren_stack)
	if (__index == __it)
	  __throw_regex_error(regex_constants::error_backref);
      _M_has_backref = true;
      this->push_back(_StateT(_S_opcode_backref, __index));
      return this->size()-1;
    }

  template<typename _CharT, typename _TraitsT>
    _StateSeq<_CharT, _TraitsT>& _StateSeq<_CharT, _TraitsT>::
    operator=(const _StateSeq& __rhs)
    {
      _M_start = __rhs._M_start;
      _M_end1  = __rhs._M_end1;
      _M_end2  = __rhs._M_end2;
      return *this;
    }

  template<typename _CharT, typename _TraitsT>
    void _StateSeq<_CharT, _TraitsT>::
    _M_push_back(_StateIdT __id)
    {
      if (_M_end1 != _S_invalid_state_id)
	_M_nfa[_M_end1]._M_next = __id;
      _M_end1 = __id;
    }

  template<typename _CharT, typename _TraitsT>
    void _StateSeq<_CharT, _TraitsT>::
    _M_append(_StateIdT __id)
    {
      if (_M_end2 != _S_invalid_state_id)
      {
	if (_M_end2 == _M_end1)
	  _M_nfa[_M_end2]._M_alt = __id;
	else
	  _M_nfa[_M_end2]._M_next = __id;
	_M_end2 = _S_invalid_state_id;
      }
      if (_M_end1 != _S_invalid_state_id)
	_M_nfa[_M_end1]._M_next = __id;
      _M_end1 = __id;
    }

  template<typename _CharT, typename _TraitsT>
    void _StateSeq<_CharT, _TraitsT>::
    _M_append(_StateSeq& __rhs)
    {
      if (_M_end2 != _S_invalid_state_id)
      {
	if (_M_end2 == _M_end1)
	  _M_nfa[_M_end2]._M_alt = __rhs._M_start;
	else
	  _M_nfa[_M_end2]._M_next = __rhs._M_start;
	_M_end2 = _S_invalid_state_id;
      }
      if (__rhs._M_end2 != _S_invalid_state_id)
	_M_end2 = __rhs._M_end2;
      if (_M_end1 != _S_invalid_state_id)
	_M_nfa[_M_end1]._M_next = __rhs._M_start;
      _M_end1 = __rhs._M_end1;
    }

  // @todo implement this function.
  template<typename _CharT, typename _TraitsT>
    _StateIdT _StateSeq<_CharT, _TraitsT>::
    _M_clone()
    { return 0; }

_GLIBCXX_END_NAMESPACE_VERSION
} // namespace __detail
} // namespace