// This file is distributed under the BSD License.
// See "license.txt" for details.
// Copyright 2009-2011, Jonathan Turner (jonathan@emptycrate.com)
// and Jason Turner (jason@emptycrate.com)
// http://www.chaiscript.com

#ifndef CHAISCRIPT_BOXED_NUMERIC_HPP_
#define CHAISCRIPT_BOXED_NUMERIC_HPP_

#include "type_info.hpp"
#include "boxed_value.hpp"
#include "boxed_cast_helper.hpp"
#include <boost/any.hpp>
#include <boost/cstdint.hpp>
#include <boost/integer_traits.hpp>

namespace chaiscript 
{
 
  /// \brief Represents any numeric type, generically. Used internally for generic operations between POD values
  class Boxed_Numeric
  {
    private:
      template<typename T, bool Const>
      struct choose_const 
      {
        typedef T& type;
      };

      template<typename T>
        struct choose_const<T, true>
        {
          typedef const T& type;
        };

      template<typename O, typename T>
        struct lhs_type
        {
          typedef typename choose_const<T, O::lhs_const>::type type;
        };

      struct equals
      {
        static const bool lhs_const = true;
        template<typename T, typename U>
        static bool go(const T &t, const U &u) { return t == u; }
      };

      struct add
      {
        static const bool lhs_const = true;
        template<typename T, typename U>
        static  Boxed_Value go(const T &t, const U &u) { return const_var(t + u); }
      };

      struct subtract
      {
        static const bool lhs_const = true;
        template<typename T, typename U>
        static  Boxed_Value go(const T &t, const U &u) { return const_var(t - u); }
      };

      struct multiply 
      {
        static const bool lhs_const = true;
        template<typename T, typename U>
        static  Boxed_Value go(const T &t, const U &u) { return const_var(t * u); }
      };

      struct divide 
      {
        static const bool lhs_const = true;
        template<typename T, typename U>
        static  Boxed_Value go(const T &t, const U &u) { return const_var(t / u); }
      };

      struct assign_product
      {
        static const bool lhs_const = false;
        template<typename T, typename U>
        static  Boxed_Value go(T &t, const U &u) { return var(&(t *= u)); }
      };

      struct assign_quotient
      {
        static const bool lhs_const = false;
        template<typename T, typename U>
        static  Boxed_Value go(T &t, const U &u) { return var(&(t /= u)); }
      };

      struct assign_sum
      {
        static const bool lhs_const = false;
        template<typename T, typename U>
        static  Boxed_Value go(T &t, const U &u) { return var(&(t += u)); }
      };

      struct assign_difference
      {
        static const bool lhs_const = false;
        template<typename T, typename U>
        static  Boxed_Value go(T &t, const U &u) { return var(&(t -= u)); }
      };

      struct pre_increment
      {
        static const bool lhs_const = false;
        template<typename T, typename U>
          static Boxed_Value go(T &t, const U) { return var(&++t); }
      };

      struct pre_decrement
      {
        static const bool lhs_const = false;

        template<typename U>
        static Boxed_Value go(boost::reference_wrapper<bool>, const U) { std::cout<< "why where?"<< std::endl; throw boost::bad_any_cast(); }

        template<typename T, typename U>
          static Boxed_Value go(T &t, const U) { return var(&--t); }
      };

      template<typename Ret, typename O, typename L>
        static Ret oper_lhs(L l, const Boxed_Numeric &r)
        {
          const Type_Info &inp_ = r.bv.get_type_info();

          if (inp_ == typeid(double))
          {
            return O::go(l, boxed_cast<const double &>(r.bv));
          } else if (inp_ == typeid(float)) {
            return O::go(l, boxed_cast<const float&>(r.bv));
          } else if (inp_ == typeid(bool)) {
            return O::go(l, boxed_cast<const bool&>(r.bv));
          } else if (inp_ == typeid(char)) {
            return O::go(l, boxed_cast<const char&>(r.bv));
          } else if (inp_ == typeid(int)) {
            return O::go(l, boxed_cast<const int&>(r.bv));
          } else if (inp_ == typeid(unsigned int)) {
            return O::go(l, boxed_cast<const unsigned int&>(r.bv));
          } else if (inp_ == typeid(long)) {
            return O::go(l, boxed_cast<const long&>(r.bv));
          } else if (inp_ == typeid(unsigned long)) {
            return O::go(l, boxed_cast<const unsigned long&>(r.bv));
          } else if (inp_ == typeid(boost::int8_t)) {
            return O::go(l, boxed_cast<const boost::int8_t &>(r.bv));
          } else if (inp_ == typeid(boost::int16_t)) {
            return O::go(l, boxed_cast<const boost::int16_t &>(r.bv));
          } else if (inp_ == typeid(boost::int32_t)) {
            return O::go(l, boxed_cast<const boost::int32_t &>(r.bv));
          } else if (inp_ == typeid(boost::int64_t)) {
            return O::go(l, boxed_cast<const boost::int64_t &>(r.bv));
          } else if (inp_ == typeid(boost::uint8_t)) {
            return O::go(l, boxed_cast<const boost::uint8_t &>(r.bv));
          } else if (inp_ == typeid(boost::uint16_t)) {
            return O::go(l, boxed_cast<const boost::uint16_t &>(r.bv));
          } else if (inp_ == typeid(boost::uint32_t)) {
            return O::go(l, boxed_cast<const boost::uint32_t &>(r.bv));
          } else {
            throw boost::bad_any_cast();
          }
        } 

      template<typename Ret, typename O>
        static Ret oper(const Boxed_Numeric &l, const Boxed_Numeric &r)
        {
          const Type_Info &inp_ = l.bv.get_type_info();

          if (inp_ == typeid(double))
          {
            return oper_lhs<Ret, O>(boxed_cast<typename lhs_type<O, double>::type>(l.bv), r);
          } else if (inp_ == typeid(float)) {
            return oper_lhs<Ret, O>(boxed_cast<typename lhs_type<O, float>::type>(l.bv), r);
          } else if (inp_ == typeid(bool)) {
            return oper_lhs<Ret, O>(boxed_cast<typename lhs_type<O, bool>::type>(l.bv), r);
          } else if (inp_ == typeid(char)) {
            return oper_lhs<Ret, O>(boxed_cast<typename lhs_type<O, char>::type>(l.bv), r);
          } else if (inp_ == typeid(int)) {
            return oper_lhs<Ret, O>(boxed_cast<typename lhs_type<O, int>::type>(l.bv), r);
          } else if (inp_ == typeid(unsigned int)) {
            return oper_lhs<Ret, O>(boxed_cast<typename lhs_type<O, unsigned int>::type>(l.bv), r);
          } else if (inp_ == typeid(long)) {
            return oper_lhs<Ret, O>(boxed_cast<typename lhs_type<O, long>::type>(l.bv), r);
          } else if (inp_ == typeid(unsigned long)) {
            return oper_lhs<Ret, O>(boxed_cast<typename lhs_type<O, unsigned long>::type>(l.bv), r);
          } else if (inp_ == typeid(boost::int8_t)) {
            return oper_lhs<Ret, O>(boxed_cast<typename lhs_type<O, boost::int8_t>::type>(l.bv), r);
          } else if (inp_ == typeid(boost::int16_t)) {
            return oper_lhs<Ret, O>(boxed_cast<typename lhs_type<O, boost::int32_t>::type>(l.bv), r);
          } else if (inp_ == typeid(boost::int32_t)) {
            return oper_lhs<Ret, O>(boxed_cast<typename lhs_type<O, boost::int32_t>::type>(l.bv), r);
          } else if (inp_ == typeid(boost::int64_t)) {
            return oper_lhs<Ret, O>(boxed_cast<typename lhs_type<O, boost::int64_t>::type>(l.bv), r);
          } else if (inp_ == typeid(boost::uint8_t)) {
            return oper_lhs<Ret, O>(boxed_cast<typename lhs_type<O, boost::uint8_t>::type>(l.bv), r);
          } else if (inp_ == typeid(boost::uint16_t)) {
            return oper_lhs<Ret, O>(boxed_cast<typename lhs_type<O, boost::uint16_t>::type>(l.bv), r);
          } else if (inp_ == typeid(boost::uint32_t)) {
            return oper_lhs<Ret, O>(boxed_cast<typename lhs_type<O, boost::uint32_t>::type>(l.bv), r);
          } else {
            throw boost::bad_any_cast();
          }
        };
      

    public:
      Boxed_Numeric(const Boxed_Value &v)
        : bv(v), d(0), i(0), isfloat(false)
      {
        const Type_Info &inp_ = v.get_type_info();

        if (!inp_.is_arithmetic())
        {
          throw boost::bad_any_cast();
        }

        if (inp_ == typeid(double))
        {
          d = boxed_cast<double>(v);
          isfloat = true;
        } else if (inp_ == typeid(float)) {
          d = boxed_cast<float>(v);
          isfloat = true;
        } else if (inp_ == typeid(bool)) {
          i = boxed_cast<bool>(v);
        } else if (inp_ == typeid(char)) {
          i = boxed_cast<char>(v);
        } else if (inp_ == typeid(int)) {
          i = boxed_cast<int>(v);
        } else if (inp_ == typeid(unsigned int)) {
          i = boxed_cast<unsigned int>(v);
        } else if (inp_ == typeid(long)) {
          i = boxed_cast<long>(v);
        } else if (inp_ == typeid(unsigned long)) {
          i = boxed_cast<unsigned long>(v);
        } else if (inp_ == typeid(boost::int8_t)) {
          i = boxed_cast<boost::int8_t>(v);
        } else if (inp_ == typeid(boost::int16_t)) {
          i = boxed_cast<boost::int16_t>(v);
        } else if (inp_ == typeid(boost::int32_t)) {
          i = boxed_cast<boost::int32_t>(v);
        } else if (inp_ == typeid(boost::int64_t)) {
          i = boxed_cast<boost::int64_t>(v);
        } else if (inp_ == typeid(boost::uint8_t)) {
          i = boxed_cast<boost::uint8_t>(v);
        } else if (inp_ == typeid(boost::uint16_t)) {
          i = boxed_cast<boost::uint16_t>(v);
        } else if (inp_ == typeid(boost::uint32_t)) {
          i = boxed_cast<boost::uint32_t>(v);
        } else {
          throw boost::bad_any_cast();
        }
      }

      bool operator==(const Boxed_Numeric &r) const
      {
        return oper<bool, equals>(*this, r);
      }

      bool operator<(const Boxed_Numeric &r) const
      {
        return ((isfloat)?d:i) < ((r.isfloat)?r.d:r.i);
      }

      bool operator>(const Boxed_Numeric &r) const
      {
        return ((isfloat)?d:i) > ((r.isfloat)?r.d:r.i);
      }

      bool operator>=(const Boxed_Numeric &r) const
      {
        return ((isfloat)?d:i) >= ((r.isfloat)?r.d:r.i);
      }

      bool operator<=(const Boxed_Numeric &r) const
      {
        return ((isfloat)?d:i) <= ((r.isfloat)?r.d:r.i);
      }

      bool operator!=(const Boxed_Numeric &r) const
      {
        return ((isfloat)?d:i) != ((r.isfloat)?r.d:r.i);
      }

      Boxed_Value operator--() const
      {
        return oper<Boxed_Value, pre_decrement>(*this, var(0));
      }

      Boxed_Value operator++() const
      {
        return oper<Boxed_Value, pre_increment>(*this, var(0));
      }

      Boxed_Value operator+(const Boxed_Numeric &r) const
      {
        return oper<Boxed_Value, add>(*this, r);
      }

      Boxed_Value operator-(const Boxed_Numeric &r) const
      {
        return oper<Boxed_Value, subtract>(*this, r);
      }

      Boxed_Value operator&(const Boxed_Numeric &r) const
      {
        if (!isfloat && !r.isfloat)
        {
          return Boxed_Value(i & r.i);
        }

        throw exception::bad_boxed_cast("& only valid for integer types");
      }

      Boxed_Value operator^(const Boxed_Numeric &r) const
      {
        if (!isfloat && !r.isfloat)
        {
          return Boxed_Value(i ^ r.i);
        }

        throw exception::bad_boxed_cast("^ only valid for integer types");
      }

      Boxed_Value operator|(const Boxed_Numeric &r) const
      {
        if (!isfloat && !r.isfloat)
        {
          return Boxed_Value(i | r.i);
        }

        throw exception::bad_boxed_cast("| only valid for integer types");
      }

      Boxed_Value operator*=(const Boxed_Numeric &r) const
      {
        return oper<Boxed_Value, assign_product>(*this, r);
      }
      Boxed_Value operator/=(const Boxed_Numeric &r) const
      {
        return oper<Boxed_Value, assign_quotient>(*this, r);
      }
      Boxed_Value operator+=(const Boxed_Numeric &r) const
      {
        return oper<Boxed_Value, assign_sum>(*this, r);
      }
      Boxed_Value operator-=(const Boxed_Numeric &r) const
      {
        return oper<Boxed_Value, assign_difference>(*this, r);
      }

      Boxed_Value operator/(const Boxed_Numeric &r) const
      {
        return oper<Boxed_Value, divide>(*this, r);
      }

      Boxed_Value operator<<(const Boxed_Numeric &r) const
      {
        if (!isfloat && !r.isfloat)
        {
          return smart_size(i << r.i);
        }

        throw exception::bad_boxed_cast("<< only valid for integer types");
      }


      Boxed_Value operator*(const Boxed_Numeric &r) const
      {
        return oper<Boxed_Value, multiply>(*this, r);
      }


      Boxed_Value operator%(const Boxed_Numeric &r) const
      {
        if (!isfloat && !r.isfloat)
        {
          return smart_size(i % r.i);
        }

        throw exception::bad_boxed_cast("% only valid for integer types");
      }

      Boxed_Value operator>>(const Boxed_Numeric &r) const
      {
        if (!isfloat && !r.isfloat)
        {
          return smart_size(i >> r.i);
        }

        throw exception::bad_boxed_cast(">> only valid for integer types");
      }

      Boxed_Value smart_size(boost::int64_t t_i) const
      {
        if (t_i < boost::integer_traits<int>::const_min
            || t_i > boost::integer_traits<int>::const_max)
        {
          return Boxed_Value(t_i);
        } else {
          return Boxed_Value(static_cast<int>(t_i));
        }
      }


      Boxed_Value bv;
      double d;
      boost::int64_t i;

      bool isfloat;
  };

  namespace detail
  {
    /**
     * Cast_Helper for converting from Boxed_Value to Boxed_Numeric
     */
    template<>
      struct Cast_Helper<Boxed_Numeric>
      {
        typedef Boxed_Numeric Result_Type;

        static Result_Type cast(const Boxed_Value &ob)
        {
          return Boxed_Numeric(ob);
        }
      };

    /**
     * Cast_Helper for converting from Boxed_Value to Boxed_Numeric
     */
    template<>
      struct Cast_Helper<const Boxed_Numeric &> : Cast_Helper<Boxed_Numeric>
      {
      };
      
    /**
     * Cast_Helper for converting from Boxed_Value to Boxed_Numeric
     */
    template<>
      struct Cast_Helper<const Boxed_Numeric> : Cast_Helper<Boxed_Numeric>
      {
      };  
  }
  
}



#endif