/*=============================================================================
    Copyright (c) 2002 2004 2006 Joel de Guzman
    http://spirit.sourceforge.net/

    Use, modification and distribution is 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)
=============================================================================*/
#include "template_stack.hpp"

#ifdef BOOST_MSVC
#pragma warning(disable : 4355)
#endif

namespace quickbook
{
    template_stack::template_stack()
        : scope(template_stack::parser(*this))
        , scopes()
    {
        scopes.push_front(template_scope());
    }
    
    template_symbol const* template_stack::find(std::string const& symbol) const
    {
        for (template_scope const* i = &*scopes.begin(); i; i = i->parent_scope)
        {
            if (template_symbol const* ts = i->symbols.find(symbol.c_str()))
                return ts;
        }
        return 0;
    }

    template_symbol const* template_stack::find_top_scope(std::string const& symbol) const
    {
        return scopes.front().symbols.find(symbol.c_str());
    }

    template_symbols const& template_stack::top() const
    {
        BOOST_ASSERT(!scopes.empty());
        return scopes.front().symbols;
    }

    template_scope const& template_stack::top_scope() const
    {
        BOOST_ASSERT(!scopes.empty());
        return scopes.front();
    }
    
    // TODO: Should symbols defined by '[import]' use the current scope?
    void template_stack::add(std::string const& symbol, template_symbol const& ts)
    {
        BOOST_ASSERT(!scopes.empty());
        scopes.front().symbols.add(symbol.c_str(),
            boost::get<2>(ts) ? ts :
            template_symbol(boost::get<0>(ts), boost::get<1>(ts), &top_scope()));
    }    
    
    void template_stack::push()
    {
        template_scope const& old_front = scopes.front();
        scopes.push_front(template_scope());
        set_parent_scope(old_front);
    }

    void template_stack::pop()
    {
        scopes.pop_front();
    }

    void template_stack::set_parent_scope(template_scope const& parent)
    {
        scopes.front().parent_scope = &parent;
    }
}