// Copyright (C) 2013 Romain Francois

//

// This file is part of Rcpp.

//

// Rcpp 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 2 of the License, or

// (at your option) any later version.

//

// Rcpp 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.

//

// You should have received a copy of the GNU General Public License

// along with Rcpp. If not, see <http://www.gnu.org/licenses/>.

#ifndef Rcpp_proxy_AttributeProxy_h

#define Rcpp_proxy_AttributeProxy_h

namespace Rcpp{

template <typename CLASS>

class AttributeProxyPolicy {

public:

class AttributeProxy : public GenericProxy<AttributeProxy> {

public:

AttributeProxy( CLASS& v, const std::string& name)

: parent(v), attr_name(Rf_install(name.c_str()))

{}

AttributeProxy& operator=(const AttributeProxy& rhs){

if( this != &rhs ) set( rhs.get() ) ;

return *this ;

}

template <typename T> AttributeProxy& operator=(const T& rhs);

template <typename T> operator T() const;

inline operator SEXP() const;

private:

CLASS& parent;

SEXP attr_name ;

SEXP get() const {

return Rf_getAttrib( parent, attr_name ) ;

}

void set(SEXP x ){

Rf_setAttrib( parent, attr_name, Shield<SEXP>(x) ) ;

}

} ;

class const_AttributeProxy : public GenericProxy<const_AttributeProxy> {

public:

const_AttributeProxy( const CLASS& v, const std::string& name)

: parent(v), attr_name(Rf_install(name.c_str())){}

template <typename T> operator T() const;

inline operator SEXP() const;

private:

const CLASS& parent;

SEXP attr_name ;

SEXP get() const {

return Rf_getAttrib( parent, attr_name ) ;

}

} ;

AttributeProxy attr( const std::string& name){

return AttributeProxy( static_cast<CLASS&>( *this ), name ) ;

}

const_AttributeProxy attr( const std::string& name) const {

return const_AttributeProxy( static_cast<const CLASS&>( *this ), name ) ;

}

std::vector<std::string> attributeNames() const {

std::vector<std::string> v;

#if R_VERSION >= R_Version(4, 6, 0)

SEXP attrs = R_getAttribNames( static_cast<const CLASS&>(*this));

R_xlen_t n = XLENGTH(attrs);

for (R_xlen_t i = 0; i < n; i++) {

v.push_back(std::string(CHAR(STRING_ELT(attrs, i))));

}

#else

SEXP attrs = ATTRIB( static_cast<const CLASS&>(*this) );

while( attrs != R_NilValue ){

v.push_back( std::string(CHAR(PRINTNAME(TAG(attrs)))) ) ;

attrs = CDR( attrs ) ;

}

#endif

return v;

}

bool hasAttribute(const std::string& attr) const {

#if R_VERSION >= R_Version(4, 6, 0)

return R_hasAttrib(static_cast<const CLASS&>(*this), Rf_install(attr.c_str()));

#else

return static_cast<const CLASS&>(*this).attr(attr) != R_NilValue;

#endif

}

} ;

}

#endif