#ifndef BOOST_MATH_POLICY_HPP
#define BOOST_MATH_POLICY_HPP

#define BOOST_PARAMETER_MAX_ARITY 15

#include <boost/parameter.hpp>
#include <boost/mpl/list.hpp>
#include <boost/mpl/contains.hpp>

namespace boost{ namespace math{ namespace policy{

//
// Define macros for our default policies, if they're not defined already:
//
#ifndef BOOST_MATH_DOMAIN_ERROR_POLICY
#define BOOST_MATH_DOMAIN_ERROR_POLICY throw_on_error
#endif
#ifndef BOOST_MATH_POLE_ERROR_POLICY
#define BOOST_MATH_POLE_ERROR_POLICY throw_on_error
#endif
#ifndef BOOST_MATH_OVERFLOW_ERROR_POLICY
#define BOOST_MATH_OVERFLOW_ERROR_POLICY throw_on_error
#endif
#ifndef BOOST_MATH_EVALUATION_ERROR_POLICY
#define BOOST_MATH_EVALUATION_ERROR_POLICY throw_on_error
#endif
#ifndef BOOST_MATH_UNDERFLOW_ERROR_POLICY
#define BOOST_MATH_UNDERFLOW_ERROR_POLICY ignor_error
#endif
#ifndef BOOST_MATH_DENORM_ERROR_POLICY
#define BOOST_MATH_DENORM_ERROR_POLICY ignor_error
#endif
#ifndef BOOST_MATH_DIGITS10_POLICY
#define BOOST_MATH_DIGITS10_POLICY -1
#endif
#ifndef BOOST_MATH_PROMOTE_FLOAT_POLICY
#define BOOST_MATH_PROMOTE_FLOAT_POLICY true
#endif
#ifndef BOOST_MATH_PROMOTE_DOUBLE_POLICY
#define BOOST_MATH_PROMOTE_DOUBLE_POLICY true
#endif
#ifndef BOOST_MATH_DISCRETE_QUANTILE_POLICY
#define BOOST_MATH_DISCRETE_QUANTILE_POLICY integer_outside
#endif

#if !defined(__BORLANDC__)
#define BOOST_MATH_META_INT(type, name)\
   template <type N> struct name : public boost::mpl::int_<N>{};\
   namespace detail{\
   template <class T> struct is_##name##_imp\
   {\
      template <type N> static char test(const name<N>&);\
      static double test(...);\
      BOOST_STATIC_CONSTANT(bool, value = sizeof(test(T())) == 1);\
   };\
   }\
   template <class T> struct is_##name : public boost::mpl::bool_<detail::is_##name##_imp<T>::value>{};

#define BOOST_MATH_META_BOOL(name)\
   template <bool N> struct name : public boost::mpl::bool_<N>{};\
   namespace detail{\
   template <class T> struct is_##name##_imp\
   {\
      template <bool N> static char test(const name<N>&);\
      static double test(...);\
      BOOST_STATIC_CONSTANT(bool, value = sizeof(test(T())) == 1);\
   };\
   }\
   template <class T> struct is_##name : public boost::mpl::bool_<detail::is_##name##_imp<T>::value>{};
#else
#define BOOST_MATH_META_INT(Type, name)\
   template <Type N> struct name : public boost::mpl::int_<N>{};\
   namespace detail{\
   template <class T> struct is_##name##_tester\
   {\
      template <bool N> static char test(const name<N>&);\
      static double test(...);\
   };\
   template <class T> struct is_##name##_imp\
   {\
      static T inst;\
      BOOST_STATIC_CONSTANT(bool, value = sizeof(detail::is_##name##_tester<T>::test(inst)) == 1);\
   };\
   }\
   template <class T> struct is_##name : public boost::mpl::bool_<detail::is_##name##_imp<T>::value>\
   {\
      template <class U, class V> struct apply{ typedef is_##name<U> type; };\
   };

#define BOOST_MATH_META_BOOL(name)\
   template <bool N> struct name : public boost::mpl::bool_<N>{};\
   namespace detail{\
   template <class T> struct is_##name##_tester\
   {\
      template <bool N> static char test(const name<N>&);\
      static double test(...);\
   };\
   template <class T> struct is_##name##_imp\
   {\
      static T inst;\
      BOOST_STATIC_CONSTANT(bool, value = sizeof(detail::is_##name##_tester<T>::test(inst)) == 1);\
   };\
   }\
   template <class T> struct is_##name : public boost::mpl::bool_<detail::is_##name##_imp<T>::value>\
   {\
      template <class U, class V> struct apply{ typedef is_##name<U> type;  };\
   };
#endif
//
// Begin by defining policy types for error handling:
//
enum error_policy_type
{
   throw_on_error = 0,
   errno_on_error = 1,
   ignor_error = 2,
   user_error = 3
};

BOOST_MATH_META_INT(error_policy_type, domain_error)
BOOST_MATH_META_INT(error_policy_type, pole_error)
BOOST_MATH_META_INT(error_policy_type, overflow_error)
BOOST_MATH_META_INT(error_policy_type, underflow_error)
BOOST_MATH_META_INT(error_policy_type, denorm_error)
BOOST_MATH_META_INT(error_policy_type, evaluation_error)

//
// Policy types for internal promotion:
//
BOOST_MATH_META_BOOL(promote_float);
BOOST_MATH_META_BOOL(promote_double);
//
// Policy types for discrete quantiles:
//
enum discrete_quantile_policy_type
{
   real,
   integer_outside,
   integer_inside,
   integer_below,
   integer_above
};

BOOST_MATH_META_INT(discrete_quantile_policy_type, discrete_quantile);
//
// Precision:
//
BOOST_MATH_META_INT(int, digits10);
BOOST_MATH_META_INT(int, digits2);
//
// Define the names for each possible policy:
//
#define BOOST_MATH_PARAMETER(name)\
   BOOST_PARAMETER_TEMPLATE_KEYWORD(name##_name)\
   BOOST_PARAMETER_NAME(name##_name)
//
// Error handlers:
//
BOOST_MATH_PARAMETER(domain_error)
BOOST_MATH_PARAMETER(pole_error)
BOOST_MATH_PARAMETER(overflow_error)
BOOST_MATH_PARAMETER(underflow_error)
BOOST_MATH_PARAMETER(denorm_error)
BOOST_MATH_PARAMETER(evaluation_error)
//
// Precision:
//
BOOST_MATH_PARAMETER(digits10)
BOOST_MATH_PARAMETER(digits2)
//
// Internal promotion:
//
BOOST_MATH_PARAMETER(promote_float)
BOOST_MATH_PARAMETER(promote_double)
//
// Discrete quantile handling:
//
BOOST_MATH_PARAMETER(discrete_quantile)

namespace detail{
//
// Trait to work out bits precision from digits10 and digits2:
//
template <class Digits10, class Digits2>
struct precision
{
   //
   // Now work out the precision:
   //
   typedef digits2<((Digits10::value + 1) * 1000L) / 301L> digits2_type;
public:
#ifdef __BORLANDC__
   typedef typename mpl::if_c<
      (Digits2::value > ::boost::math::policy::detail::precision<Digits10,Digits2>::digits2_type::value),
      Digits2, digits2_type>::type type;
#else
   typedef typename mpl::if_c<
      (Digits2::value > digits2_type::value),
      Digits2, digits2_type>::type type;
#endif
};

}

//
// Define template signature complete with error checking of types:
//
using boost::mpl::_;
typedef parameter::parameters<
   parameter::optional<parameter::deduced<tag::domain_error_name>, is_domain_error<mpl::_> >
   , parameter::optional<parameter::deduced<tag::pole_error_name>, is_pole_error<mpl::_> >
   , parameter::optional<parameter::deduced<tag::overflow_error_name>, is_overflow_error<mpl::_> >
   , parameter::optional<parameter::deduced<tag::underflow_error_name>, is_underflow_error<mpl::_> >
   , parameter::optional<parameter::deduced<tag::denorm_error_name>, is_denorm_error<mpl::_> >
   , parameter::optional<parameter::deduced<tag::evaluation_error_name>, is_evaluation_error<mpl::_> >
   , parameter::optional<parameter::deduced<tag::digits10_name>, is_digits10<mpl::_> >
   , parameter::optional<parameter::deduced<tag::digits2_name>, is_digits2<mpl::_> >
   , parameter::optional<parameter::deduced<tag::promote_float_name>, is_promote_float<mpl::_> >
   , parameter::optional<parameter::deduced<tag::promote_double_name>, is_promote_double<mpl::_> >
   , parameter::optional<parameter::deduced<tag::discrete_quantile_name>, is_discrete_quantile<mpl::_> >
> policy_signature;

//
// Now define the policy type with enough arguments to handle all
// the policies:
//
template <class A1 = parameter::void_, 
          class A2 = parameter::void_, 
          class A3 = parameter::void_,
          class A4 = parameter::void_,
          class A5 = parameter::void_,
          class A6 = parameter::void_,
          class A7 = parameter::void_,
          class A8 = parameter::void_,
          class A9 = parameter::void_,
          class A10 = parameter::void_,
          class A11 = parameter::void_>
struct policy
{
   typedef policy_signature::bind<A1,A2,A3,A4,A5,A6,A7,A8,A9,A10,A11, parameter::void_, parameter::void_, parameter::void_, parameter::void_> bound_type;
   typedef typename bound_type::type args;

   typedef typename boost::parameter::binding<
      args, tag::domain_error_name, domain_error<BOOST_MATH_DOMAIN_ERROR_POLICY> >::type domain_error_type;
   typedef typename boost::parameter::binding<
      args, tag::pole_error_name, pole_error<BOOST_MATH_POLE_ERROR_POLICY> >::type pole_error_type;
   typedef typename boost::parameter::binding<
      args, tag::overflow_error_name, overflow_error<BOOST_MATH_OVERFLOW_ERROR_POLICY> >::type overflow_error_type;
   typedef typename boost::parameter::binding<
      args, tag::underflow_error_name, underflow_error<BOOST_MATH_UNDERFLOW_ERROR_POLICY> >::type underflow_error_type;
   typedef typename boost::parameter::binding<
      args, tag::denorm_error_name, denorm_error<BOOST_MATH_DENORM_ERROR_POLICY> >::type denorm_error_type;
   typedef typename boost::parameter::binding<
      args, tag::evaluation_error_name, evaluation_error<BOOST_MATH_EVALUATION_ERROR_POLICY> >::type evaluation_error_type;
private:
   //
   // Now work out the precision:
   //
   typedef typename boost::parameter::binding<
      args, tag::digits10_name, digits10<BOOST_MATH_DIGITS10_POLICY> >::type digits10_type;
   typedef typename boost::parameter::binding<
      args, tag::digits2_name, digits2<-1> >::type bits_precision_type;
public:
   typedef typename detail::precision<digits10_type, bits_precision_type>::type precision_type;
   //
   // Internal promotion:
   //
   typedef typename boost::parameter::binding<
      args, tag::promote_float_name, mpl::bool_<BOOST_MATH_PROMOTE_FLOAT_POLICY> >::type float_promote_type;
   typedef typename boost::parameter::binding<
      args, tag::promote_double_name, mpl::bool_<BOOST_MATH_PROMOTE_DOUBLE_POLICY> >::type double_promote_type;
   //
   // Discrete quantiles:
   //
   typedef typename boost::parameter::binding<
      args, tag::discrete_quantile_name, discrete_quantile<BOOST_MATH_DISCRETE_QUANTILE_POLICY> >::type discrete_quantile_type;
};

template <class args>
struct make_policy_result
{
private:
   typedef typename boost::parameter::value_type<
      args, tag::domain_error_name, domain_error<BOOST_MATH_DOMAIN_ERROR_POLICY> >::type domain_error_type;
   typedef typename boost::parameter::value_type<
      args, tag::pole_error_name, pole_error<BOOST_MATH_POLE_ERROR_POLICY> >::type pole_error_type;
   typedef typename boost::parameter::value_type<
      args, tag::overflow_error_name, overflow_error<BOOST_MATH_OVERFLOW_ERROR_POLICY> >::type overflow_error_type;
   typedef typename boost::parameter::value_type<
      args, tag::underflow_error_name, underflow_error<BOOST_MATH_UNDERFLOW_ERROR_POLICY> >::type underflow_error_type;
   typedef typename boost::parameter::value_type<
      args, tag::denorm_error_name, denorm_error<BOOST_MATH_DENORM_ERROR_POLICY> >::type denorm_error_type;
   typedef typename boost::parameter::value_type<
      args, tag::evaluation_error_name, evaluation_error<BOOST_MATH_EVALUATION_ERROR_POLICY> >::type evaluation_error_type;
   //
   // Now work out the precision:
   //
   typedef typename boost::parameter::value_type<
      args, tag::digits10_name, digits10<BOOST_MATH_DIGITS10_POLICY> >::type digits10_type;
   typedef typename boost::parameter::value_type<
      args, tag::digits2_name, digits2<-1> >::type bits_precision_type;
   typedef typename detail::precision<digits10_type, bits_precision_type>::type precision_type;
   //
   // Internal promotion:
   //
   typedef typename boost::parameter::value_type<
      args, tag::promote_float_name, promote_float<BOOST_MATH_PROMOTE_FLOAT_POLICY> >::type float_promote_type;
   typedef typename boost::parameter::value_type<
      args, tag::promote_double_name, promote_double<BOOST_MATH_PROMOTE_DOUBLE_POLICY> >::type double_promote_type;
   //
   // Discrete quantiles:
   //
   typedef typename boost::parameter::value_type<
      args, tag::discrete_quantile_name, discrete_quantile<BOOST_MATH_DISCRETE_QUANTILE_POLICY> >::type discrete_quantile_type;
public:
   typedef policy<
      domain_error_type,
      pole_error_type,
      overflow_error_type,
      underflow_error_type,
      denorm_error_type,
      evaluation_error_type,
      precision_type,
      float_promote_type,
      double_promote_type,
      discrete_quantile_type > type;
};

BOOST_PARAMETER_FUNCTION(
      // 1. parenthesized return type:
      (typename make_policy_result<Args>::type),
      // 2. name of the function template:
      make_policy,
      // 3. namespace of tag types:
      tag,
      // All parameters are deduced based on their type:
      (deduced
         //    optional parameters, with defaults:
         (optional              
            (domain_error_name, *(is_domain_error<mpl::_>), domain_error<BOOST_MATH_DOMAIN_ERROR_POLICY>())
            (pole_error_name, *(is_pole_error<mpl::_>), pole_error<BOOST_MATH_POLE_ERROR_POLICY>())
            (overflow_error_name, *(is_overflow_error<mpl::_>), overflow_error<BOOST_MATH_OVERFLOW_ERROR_POLICY>())
            (underflow_error_name, *(is_underflow_error<mpl::_>), underflow_error<BOOST_MATH_UNDERFLOW_ERROR_POLICY>())
            (denorm_error_name, *(is_denorm_error<mpl::_>), denorm_error<BOOST_MATH_DENORM_ERROR_POLICY>())
            (evaluation_error_name, *(is_evaluation_error<mpl::_>), evaluation_error<BOOST_MATH_EVALUATION_ERROR_POLICY>())
            (digits10_name, *(is_digits10<mpl::_>), digits10<BOOST_MATH_DIGITS10_POLICY>())
            (digits2_name, *(is_digits2<mpl::_>), digits2<-1>())
            (promote_float_name, *(is_promote_float<mpl::_>), promote_float<BOOST_MATH_PROMOTE_FLOAT_POLICY>())
            (promote_double_name, *(is_promote_double<mpl::_>), promote_double<BOOST_MATH_PROMOTE_DOUBLE_POLICY>())
            (discrete_quantile_name, *(is_discrete_quantile<mpl::_>), discrete_quantile<BOOST_MATH_DISCRETE_QUANTILE_POLICY>())
          )
      )
  )
  {
     return typename make_policy_result<Args>::type();
  }

//
// Define a functor that normalises a policy object, and also
// merges it with whatever additional properties we wish to
// override.  We use this to reduce code bloat by ensuring that
// two policy objects with the same policies installed, will 
// end up as the same type internally no matter how they were
// created.  Also lets us change some values: for example if
// promotion has already occured once, we don't want to allow it
// a second time.
//
typedef parameter::parameters<
   parameter::optional<parameter::deduced<tag::domain_error_name>, is_domain_error<mpl::_> >
   , parameter::optional<parameter::deduced<tag::pole_error_name>, is_pole_error<mpl::_> >
   , parameter::optional<parameter::deduced<tag::overflow_error_name>, is_overflow_error<mpl::_> >
   , parameter::optional<parameter::deduced<tag::underflow_error_name>, is_underflow_error<mpl::_> >
   , parameter::optional<parameter::deduced<tag::denorm_error_name>, is_denorm_error<mpl::_> >
   , parameter::optional<parameter::deduced<tag::evaluation_error_name>, is_evaluation_error<mpl::_> >
   , parameter::optional<parameter::deduced<tag::digits10_name>, is_digits10<mpl::_> >
   , parameter::optional<parameter::deduced<tag::digits2_name>, is_digits2<mpl::_> >
   , parameter::optional<parameter::deduced<tag::promote_float_name>, is_promote_float<mpl::_> >
   , parameter::optional<parameter::deduced<tag::promote_double_name>, is_promote_double<mpl::_> >
   , parameter::optional<parameter::deduced<tag::discrete_quantile_name>, is_discrete_quantile<mpl::_> >
> normalise_signature;

template <class Policy, 
          class A1 = parameter::void_, 
          class A2 = parameter::void_, 
          class A3 = parameter::void_,
          class A4 = parameter::void_,
          class A5 = parameter::void_,
          class A6 = parameter::void_,
          class A7 = parameter::void_,
          class A8 = parameter::void_,
          class A9 = parameter::void_,
          class A10 = parameter::void_,
          class A11 = parameter::void_>
struct normalise
{
private:
   typedef typename
      normalise_signature::bind<A1,A2,A3,A4,A5,A6,A7,A8,A9,A10,A11, parameter::void_, parameter::void_, parameter::void_, parameter::void_>::type args;

   typedef typename boost::parameter::binding<
      args, tag::domain_error_name, typename Policy::domain_error_type>::type domain_error_type;
   typedef typename boost::parameter::binding<
      args, tag::pole_error_name, typename Policy::pole_error_type>::type pole_error_type;
   typedef typename boost::parameter::binding<
      args, tag::overflow_error_name, typename Policy::overflow_error_type>::type overflow_error_type;
   typedef typename boost::parameter::binding<
      args, tag::underflow_error_name, typename Policy::underflow_error_type>::type underflow_error_type;
   typedef typename boost::parameter::binding<
      args, tag::denorm_error_name, typename Policy::denorm_error_type>::type denorm_error_type;
   typedef typename boost::parameter::binding<
      args, tag::evaluation_error_name, typename Policy::evaluation_error_type>::type evaluation_error_type;
   //
   // Now work out the precision:
   //
   typedef typename boost::parameter::binding<
      args, tag::digits10_name, digits10<-1> >::type digits10_type;
   typedef typename boost::parameter::binding<
      args, tag::digits2_name, typename Policy::precision_type>::type bits_precision_type;
   typedef typename detail::precision<digits10_type, bits_precision_type>::type precision_type;
   //
   // Internal promotion:
   //
   typedef typename boost::parameter::binding<
      args, tag::promote_float_name, typename Policy::promote_float_type >::type float_promote_type;
   typedef typename boost::parameter::binding<
      args, tag::promote_double_name, typename Policy::promote_double_type>::type double_promote_type;
   //
   // Discrete quantiles:
   //
   typedef typename boost::parameter::binding<
      args, tag::discrete_quantile_name, typename Policy::discrete_quantile_type>::type discrete_quantile_type;
public:
   typedef policy<
      domain_error_type,
      pole_error_type,
      overflow_error_type,
      underflow_error_type,
      denorm_error_type,
      evaluation_error_type,
      precision_type,
      float_promote_type,
      double_promote_type,
      discrete_quantile_type > type;
};

}}} // namespaces

#endif // BOOST_MATH_POLICY_HPP