// Copyright (C) 2000-2007, Luca Padovani <padovani@sti.uniurb.it>.
// 
// This file is part of GtkMathView, a flexible, high-quality rendering
// engine for MathML documents.
// 
// GtkMathView 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 3 of the License, or
// (at your option) any later version.
// 
// GtkMathView 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 program.  If not, see <http://www.gnu.org/licenses/>.

#ifndef __TemplateReaderRefinementContext_hh__
#define __TemplateReaderRefinementContext_hh__

#include <list>

#include "Attribute.hh"
#include "AttributeSet.hh"

template <class Reader>
class TemplateReaderRefinementContext
{
public:
  TemplateReaderRefinementContext(void) { }

  SmartPtr<Attribute>
  get(const class AttributeSignature& sig) const
  {
    for (typename std::list<Context>::const_iterator p = context.begin(); p != context.end(); p++)
      {
	const Context& c = *p;
	
	if (SmartPtr<Attribute> attr = c.attributes->get(ATTRIBUTE_ID_OF_SIGNATURE(sig)))
	  return attr;
	else if (const String* rawValue = c.get(sig.name))
	  {
	    SmartPtr<Attribute> attr = Attribute::create(sig, *rawValue);
	    c.attributes->set(attr);
	    return attr;
	  }
      }
    
    return 0;
  }
  
  void
  push(const SmartPtr<Reader>& reader)
  {
    assert(reader);
    context.push_front(Context(reader));
  }

  void pop(void)
  {
    assert(!context.empty());
    context.pop_front();
  }

private:
  struct Context
  {
    typedef std::pair<String, String> RawAttribute;

    Context(const SmartPtr<Reader>& reader) : attributes(AttributeSet::create())
    {
      for (int index = 0; index < reader->getAttributeCount(); index++)
	{
	  String namespaceURI;
	  String name;
	  String value;
	  reader->getAttribute(index, namespaceURI, name, value);
	  if (namespaceURI.empty()) rawAttributes.push_back(RawAttribute(name, value));
	}
    }

    const String* get(const String& name) const
    {
      for (std::vector<RawAttribute>::const_iterator p = rawAttributes.begin(); p != rawAttributes.end(); p++)
	if (p->first == name) return &p->second;
      return 0;
    }

    std::vector<std::pair<String, String> > rawAttributes;
    SmartPtr<AttributeSet> attributes;
  };

  std::list<Context> context;
};

#endif // __TemplateReaderRefinementContext_hh__