#ifndef ARABICA_XPATHIC_XPATH_ARITHMETIC_HPP
#define ARABICA_XPATHIC_XPATH_ARITHMETIC_HPP

#include "xpath_value.hpp"

namespace Arabica
{
namespace XPath
{
namespace impl
{

template<class string_type, class string_adaptor>
class PlusOperator : private BinaryExpression<string_type, string_adaptor>, 
                     public XPathExpression<string_type, string_adaptor>
{
  typedef BinaryExpression<string_type, string_adaptor> baseT;
public:
  PlusOperator(XPathExpression<string_type, string_adaptor>* lhs, XPathExpression<string_type, string_adaptor>* rhs) : 
      BinaryExpression<string_type, string_adaptor>(lhs, rhs) { }

  virtual XPathValue<string_type, string_adaptor> evaluate(const DOM::Node<string_type, string_adaptor>& context, 
                                              const ExecutionContext<string_type, string_adaptor>& executionContext) const 
  {
    return NumericValue<string_type, string_adaptor>::createValue(baseT::lhs()->evaluateAsNumber(context, executionContext) + baseT::rhs()->evaluateAsNumber(context, executionContext));
  } // evaluate
}; // class PlusOperator

template<class string_type, class string_adaptor>
class MinusOperator : private BinaryExpression<string_type, string_adaptor>, 
                      public XPathExpression<string_type, string_adaptor>
{
  typedef BinaryExpression<string_type, string_adaptor> baseT;
public:
  MinusOperator(XPathExpression<string_type, string_adaptor>* lhs, XPathExpression<string_type, string_adaptor>* rhs) : 
      BinaryExpression<string_type, string_adaptor>(lhs, rhs) { }

  virtual XPathValue<string_type, string_adaptor> evaluate(const DOM::Node<string_type, string_adaptor>& context, 
                                              const ExecutionContext<string_type, string_adaptor>& executionContext) const
  {
    return NumericValue<string_type, string_adaptor>::createValue(baseT::lhs()->evaluateAsNumber(context, executionContext) - baseT::rhs()->evaluateAsNumber(context, executionContext));
  } // evaluate
}; // class MinusOperator

template<class string_type, class string_adaptor>
class MultiplyOperator : private BinaryExpression<string_type, string_adaptor>, 
                         public XPathExpression<string_type, string_adaptor>
{
  typedef BinaryExpression<string_type, string_adaptor> baseT;
public:
  MultiplyOperator(XPathExpression<string_type, string_adaptor>* lhs, XPathExpression<string_type, string_adaptor>* rhs) :
      BinaryExpression<string_type, string_adaptor>(lhs, rhs) { }

  virtual XPathValue<string_type, string_adaptor> evaluate(const DOM::Node<string_type, string_adaptor>& context, 
                                              const ExecutionContext<string_type, string_adaptor>& executionContext) const
  {
    return NumericValue<string_type, string_adaptor>::createValue(baseT::lhs()->evaluateAsNumber(context, executionContext) * baseT::rhs()->evaluateAsNumber(context, executionContext));
  } // evaluate
}; // class MultiplyOperator

template<class string_type, class string_adaptor>
class DivideOperator : private BinaryExpression<string_type, string_adaptor>, 
                       public XPathExpression<string_type, string_adaptor>
{
  typedef BinaryExpression<string_type, string_adaptor> baseT;
public:
  DivideOperator(XPathExpression<string_type, string_adaptor>* lhs, XPathExpression<string_type, string_adaptor>* rhs) :
      BinaryExpression<string_type, string_adaptor>(lhs, rhs) { }

  virtual XPathValue<string_type, string_adaptor> evaluate(const DOM::Node<string_type, string_adaptor>& context, 
                                              const ExecutionContext<string_type, string_adaptor>& executionContext) const
  {
    return NumericValue<string_type, string_adaptor>::createValue(baseT::lhs()->evaluateAsNumber(context, executionContext) / baseT::rhs()->evaluateAsNumber(context, executionContext));
  } // evaluate
}; // class DivideOperator

template<class string_type, class string_adaptor>
class ModOperator : private BinaryExpression<string_type, string_adaptor>, 
                    public XPathExpression<string_type, string_adaptor>
{
  typedef BinaryExpression<string_type, string_adaptor> baseT;
public:
  ModOperator(XPathExpression<string_type, string_adaptor>* lhs, XPathExpression<string_type, string_adaptor>* rhs) :
      BinaryExpression<string_type, string_adaptor>(lhs, rhs) { }

  virtual XPathValue<string_type, string_adaptor> evaluate(const DOM::Node<string_type, string_adaptor>& context, 
                                              const ExecutionContext<string_type, string_adaptor>& executionContext) const
  {
    double l = baseT::lhs()->evaluateAsNumber(context, executionContext);
    double r = baseT::rhs()->evaluateAsNumber(context, executionContext);

    if(isNaN(l) || isNaN(r))
      return NumericValue<string_type, string_adaptor>::createValue(NaN);
    return NumericValue<string_type, string_adaptor>::createValue(static_cast<long>(l) % static_cast<long>(r));
  } // evaluate
}; // class ModOperator

template<class string_type, class string_adaptor>
class UnaryNegative : private UnaryExpression<string_type, string_adaptor>, 
                      public XPathExpression<string_type, string_adaptor>
{
  typedef UnaryExpression<string_type, string_adaptor> baseT;
public:
  UnaryNegative(XPathExpression<string_type, string_adaptor>* expr) :
      UnaryExpression<string_type, string_adaptor>(expr) { }

  virtual XPathValue<string_type, string_adaptor> evaluate(const DOM::Node<string_type, string_adaptor>& context, 
                                              const ExecutionContext<string_type, string_adaptor>& executionContext) const
  {
    return NumericValue<string_type, string_adaptor>::createValue(-baseT::expr()->evaluate(context, executionContext).asNumber());
  } // evaluate
}; // class UnaryNegative

} // namespace impl
} // namespace XPath
} // namespace Arabica

#endif