// 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_BOOTSTRAP_HPP_
#define CHAISCRIPT_BOOTSTRAP_HPP_

#include "dispatchkit.hpp"
#include "dynamic_object.hpp"
#include "register_function.hpp"
#include "operators.hpp"
#include "boxed_number.hpp"
#include <sstream>
#include <type_traits>

namespace chaiscript 
{
  /// \brief Classes and functions useful for bootstrapping of ChaiScript and adding of new types
  namespace bootstrap
  {
    namespace detail
    {
      /// \brief Constructs a new POD value object from a Boxed_Number
      /// \param[in] v Boxed_Number to copy into the new object
      /// \returns The newly created object.
      template<typename P1>
      std::shared_ptr<P1> construct_pod(Boxed_Number v)
      {
        std::shared_ptr<P1> p(new P1());
        Boxed_Value bv(p);
        Boxed_Number nb(bv);
        nb = v;
        return p;
      }
    }

    /// \brief Adds a copy constructor for the given type to the given Model
    /// \param[in] type The name of the type. The copy constructor will be named "type".
    /// \param[in,out] m The Module to add the copy constructor to
    /// \tparam T The type to add a copy constructor for
    /// \returns The passed in ModulePtr, or the newly constructed one if the default param is used
    template<typename T>
    ModulePtr copy_constructor(const std::string &type, ModulePtr m = ModulePtr(new Module()))
    {
      m->add(constructor<T (const T &)>(), type);
      return m;
    }

    /// \brief Add all comparison operators for the templated type. Used during bootstrap, also available to users.
    /// \tparam T Type to create comparison operators for
    /// \param[in,out] m module to add comparison operators to
    /// \returns the passed in ModulePtr or the newly constructed one if the default params are used.
    template<typename T>
    ModulePtr opers_comparison(ModulePtr m = ModulePtr(new Module()))
    {
      operators::equal<T>(m);
      operators::greater_than<T>(m);
      operators::greater_than_equal<T>(m);
      operators::less_than<T>(m);
      operators::less_than_equal<T>(m);
      operators::not_equal<T>(m);
      return m;
    }



    /// \brief Adds default and copy constructors for the given type
    /// \param[in] type The name of the type to add the constructors for.
    /// \param[in,out] m The Module to add the basic constructors to
    /// \tparam T Type to generate basic constructors for
    /// \returns The passed in ModulePtr, or the newly constructed one if the default param is used
    /// \sa copy_constructor
    /// \sa constructor
    template<typename T>
    ModulePtr basic_constructors(const std::string &type, ModulePtr m = ModulePtr(new Module()))
    {
      m->add(constructor<T ()>(), type);
      copy_constructor<T>(type, m);
      return m;
    }

    /// \brief Adds a constructor for a POD type 
    /// \tparam T The type to add the constructor for
    /// \param[in] type The name of the type
    /// \param[in,out] m The Module to add the constructor to
    template<typename T>
    ModulePtr construct_pod(const std::string &type, ModulePtr m = ModulePtr(new Module()))
    {
      m->add(fun(&detail::construct_pod<T>), type);
      return m;
    }


    /**
    * to_string function for internal use. Uses ostream operator<<
    */
    template<typename Input>
    std::string to_string(Input i)
    {
      std::stringstream ss;
      ss << i;
      return ss.str();
    }


    /**
    * Internal function for converting from a string to a value
    * uses ostream operator >> to perform the conversion
    */
    template<typename Input>
    Input parse_string(const std::string &i)
    {
      std::stringstream ss(i);
      Input t;
      ss >> t;
      return t;
    }



    /**
    * Add all common functions for a POD type. All operators, and
    * common conversions
    */
    template<typename T>
    ModulePtr bootstrap_pod_type(const std::string &name, ModulePtr m = ModulePtr(new Module()))
    {
      m->add(user_type<T>(), name);
      m->add(constructor<T ()>(), name);
      construct_pod<T>(name, m);

      m->add(fun(&to_string<T>), "to_string");
      m->add(fun(&parse_string<T>), "to_" + name);
      return m;
    }


    /**
    * "clone" function for a shared_ptr type. This is used in the case
    * where you do not want to make a deep copy of an object during cloning
    * but want to instead maintain the shared_ptr. It is needed internally
    * for handling of Proxy_Function object (that is,
    * function variables.
    */
    template<typename Type>
    std::shared_ptr<Type> shared_ptr_clone(const std::shared_ptr<Type> &p)
    {
      return p;
    }

    /**
     * Specific version of shared_ptr_clone just for Proxy_Functions
     */
    template<typename Type>
    std::shared_ptr<typename std::remove_const<Type>::type> 
        shared_ptr_unconst_clone(const std::shared_ptr<typename std::add_const<Type>::type> &p)
    {
      return std::const_pointer_cast<typename std::remove_const<Type>::type>(p);
    }



    /**
    * Assignment function for shared_ptr objects, does not perform a copy of the
    * object pointed to, instead maintains the shared_ptr concept.
    * Similar to shared_ptr_clone. Used for Proxy_Function.
    */
    template<typename Type>
    Boxed_Value ptr_assign(Boxed_Value lhs, const std::shared_ptr<Type> &rhs)
    {
      if (lhs.is_undef() 
          || (!lhs.get_type_info().is_const() && lhs.get_type_info().bare_equal(chaiscript::detail::Get_Type_Info<Type>::get())))
      {
        lhs.assign(Boxed_Value(rhs));
        return lhs;
      } else {
        throw exception::bad_boxed_cast("type mismatch in pointer assignment");
      }
    }

    /**
    * Class consisting of only static functions. All default bootstrapping occurs
    * from this class.
    */
    class Bootstrap
    {
    private:
      /**
      * Function allowing for assignment of an unknown type to any other value
      */
      static Boxed_Value unknown_assign(Boxed_Value lhs, Boxed_Value rhs)
      {
        if (lhs.is_undef())
        {
          return (lhs.assign(rhs));
        } else {
          throw exception::bad_boxed_cast("boxed_value has a set type already");
        }
      }

      static void print(const std::string &s)
      {
        std::cout << s;
      }

      static void println(const std::string &s)
      {
        std::cout << s << std::endl;
      }


      /**
      * Add all arithmetic operators for PODs
      */
      static void opers_arithmetic_pod(ModulePtr m = ModulePtr(new Module()))
      {
        m->add(fun(&Boxed_Number::equals), "==");
        m->add(fun(&Boxed_Number::less_than), "<");
        m->add(fun(&Boxed_Number::greater_than), ">");
        m->add(fun(&Boxed_Number::greater_than_equal), ">=");
        m->add(fun(&Boxed_Number::less_than_equal), "<=");
        m->add(fun(&Boxed_Number::not_equal), "!=");

        m->add(fun(&Boxed_Number::pre_decrement), "--");
        m->add(fun(&Boxed_Number::pre_increment), "++");
        m->add(fun(&Boxed_Number::sum), "+");
        m->add(fun(&Boxed_Number::unary_plus), "+");
        m->add(fun(&Boxed_Number::unary_minus), "-");
        m->add(fun(&Boxed_Number::difference), "-");
        m->add(fun(&Boxed_Number::assign_bitwise_and), "&=");
        m->add(fun(&Boxed_Number::assign), "=");
        m->add(fun(&Boxed_Number::assign_bitwise_or), "|=");
        m->add(fun(&Boxed_Number::assign_bitwise_xor), "^=");
        m->add(fun(&Boxed_Number::assign_remainder), "%=");
        m->add(fun(&Boxed_Number::assign_shift_left), "<<=");
        m->add(fun(&Boxed_Number::assign_shift_right), ">>=");
        m->add(fun(&Boxed_Number::bitwise_and), "&");
        m->add(fun(&Boxed_Number::bitwise_complement), "~");
        m->add(fun(&Boxed_Number::bitwise_xor), "^");
        m->add(fun(&Boxed_Number::bitwise_or), "|");
        m->add(fun(&Boxed_Number::assign_product), "*=");
        m->add(fun(&Boxed_Number::assign_quotient), "/=");
        m->add(fun(&Boxed_Number::assign_sum), "+=");
        m->add(fun(&Boxed_Number::assign_difference), "-=");
        m->add(fun(&Boxed_Number::quotient), "/");
        m->add(fun(&Boxed_Number::shift_left), "<<");
        m->add(fun(&Boxed_Number::product), "*");
        m->add(fun(&Boxed_Number::remainder), "%");
        m->add(fun(&Boxed_Number::shift_right), ">>");


     }

      /**
      * Create a bound function object. The first param is the function to bind
      * the remaining parameters are the args to bind into the
      * result
      */
      static Boxed_Value bind_function(const std::vector<Boxed_Value> &params)
      {
        if (params.size() < 2)
        {
          throw exception::arity_error(static_cast<int>(params.size()), 2);
        }

        Const_Proxy_Function f = boxed_cast<Const_Proxy_Function>(params[0]);

        return Boxed_Value(Const_Proxy_Function(new dispatch::Bound_Function(f,
          std::vector<Boxed_Value>(params.begin() + 1, params.end()))));
      }

      /**
      * Returns true if a call can be made that consists of the first parameter
      * (the function) with the remaining parameters as its arguments.
      */
      static Boxed_Value call_exists(const std::vector<Boxed_Value> &params)
      {
        if (params.size() < 1)
        {
          throw exception::arity_error(static_cast<int>(params.size()), 1);
        }

        Const_Proxy_Function f = boxed_cast<Const_Proxy_Function>(params[0]);

        return Boxed_Value(f->call_match(std::vector<Boxed_Value>(params.begin() + 1, params.end())));
      }

      static bool has_guard(const Const_Proxy_Function &t_pf)
      {
        auto pf = std::dynamic_pointer_cast<const dispatch::Dynamic_Proxy_Function>(t_pf);
        if (pf)
        {
          return bool(pf->get_guard());
        } else {
          return false;
        }
      }

      static Const_Proxy_Function get_guard(const Const_Proxy_Function &t_pf)
      {
        auto pf = std::dynamic_pointer_cast<const dispatch::Dynamic_Proxy_Function>(t_pf);
        if (pf)
        {
          if (pf->get_guard())
          {
            return pf->get_guard();
          } else {
            throw std::runtime_error("Function does not have a guard");
          }
        } else {
          throw std::runtime_error("Function does not have a guard");
        }
      }

      static void throw_exception(const Boxed_Value &bv) {
        throw bv;
      }
      
      static std::shared_ptr<chaiscript::detail::Dispatch_Engine> bootstrap2(
          std::shared_ptr<chaiscript::detail::Dispatch_Engine> e 
             = std::shared_ptr<chaiscript::detail::Dispatch_Engine> (new chaiscript::detail::Dispatch_Engine()))
      {
        e->add(user_type<void>(), "void");
        return e;
      }

      static std::string what(const std::exception &e)
      {
        return e.what();
      }

      /**
       * Boolean specialization of internal to_string function 
       */
      static std::string bool_to_string(bool b)
      {
        if (b)
        {
          return "true";
        } else {
          return "false";
        }
      }

      template<typename FunctionType>
        static std::vector<Boxed_Value> do_return_boxed_value_vector(FunctionType f,
            const dispatch::Proxy_Function_Base *b)
        {
          auto v = (b->*f)();
 
          std::vector<Boxed_Value> vbv;

          for (const auto &o: v)
          {
            vbv.push_back(const_var(o));
          }

          return vbv;
        }

      template<typename Function>
      static std::function<std::vector<Boxed_Value> (const dispatch::Proxy_Function_Base*)> return_boxed_value_vector(const Function &f)
      {
        return std::bind(&do_return_boxed_value_vector<Function>, f, std::placeholders::_1);
      }

    public:
      /// \brief perform all common bootstrap functions for std::string, void and POD types
      /// \param[in,out] m Module to add bootstrapped functions to
      /// \returns passed in ModulePtr, or newly created one if default argument is used
      static ModulePtr bootstrap(ModulePtr m = ModulePtr(new Module()))
      {
        m->add(user_type<void>(), "void");
        m->add(user_type<bool>(), "bool");
        m->add(user_type<Boxed_Value>(), "Object");
        m->add(user_type<Boxed_Number>(), "Number");
        m->add(user_type<Proxy_Function>(), "Function");
        m->add(user_type<std::exception>(), "exception");

        m->add(fun(&dispatch::Proxy_Function_Base::get_arity), "get_arity");
        m->add(fun(&dispatch::Proxy_Function_Base::annotation), "get_annotation");
        m->add(fun(&dispatch::Proxy_Function_Base::operator()), "call");
        m->add(fun(&dispatch::Proxy_Function_Base::operator==), "==");

        
        m->add(fun(return_boxed_value_vector(&dispatch::Proxy_Function_Base::get_param_types)), "get_param_types");
        m->add(fun(return_boxed_value_vector(&dispatch::Proxy_Function_Base::get_contained_functions)), "get_contained_functions");


        m->add(user_type<std::runtime_error>(), "runtime_error");
        m->add(chaiscript::base_class<std::exception, std::runtime_error>());
 

        m->add(constructor<std::runtime_error (const std::string &)>(), "runtime_error");
        m->add(fun(std::function<std::string (const std::runtime_error &)>(&what)), "what");     

        m->add(user_type<dispatch::Dynamic_Object>(), "Dynamic_Object");
        m->add(constructor<dispatch::Dynamic_Object (const std::string &)>(), "Dynamic_Object");
        m->add(fun(&dispatch::Dynamic_Object::get_type_name), "get_type_name");
        m->add(fun(&dispatch::Dynamic_Object::get_attrs), "get_attrs");
        m->add(fun(&dispatch::Dynamic_Object::get_attr), "get_attr");

        m->eval("def Dynamic_Object::clone() { auto &new_o = Dynamic_Object(this.get_type_name()); for_each(this.get_attrs(), bind(fun(new_o, x) { new_o.get_attr(x.first) = x.second; }, new_o, _) ); return new_o; }");

        m->add(fun(&has_guard), "has_guard");
        m->add(fun(&get_guard), "get_guard");

        m->add(fun(&Boxed_Value::is_undef), "is_var_undef");
        m->add(fun(&Boxed_Value::is_null), "is_var_null");
        m->add(fun(&Boxed_Value::is_const), "is_var_const");
        m->add(fun(&Boxed_Value::is_ref), "is_var_reference");
        m->add(fun(&Boxed_Value::is_pointer), "is_var_pointer");
        m->add(fun(&Boxed_Value::is_type), "is_type");

        m->add(fun(&Boxed_Value::get_type_info), "get_type_info");
        m->add(user_type<Type_Info>(), "Type_Info");


        operators::equal<Type_Info>(m);

        m->add(fun(&Type_Info::is_const), "is_type_const");
        m->add(fun(&Type_Info::is_reference), "is_type_reference");
        m->add(fun(&Type_Info::is_void), "is_type_void");
        m->add(fun(&Type_Info::is_undef), "is_type_undef");
        m->add(fun(&Type_Info::is_pointer), "is_type_pointer");
        m->add(fun(&Type_Info::name), "cpp_name");
        m->add(fun(&Type_Info::bare_name), "cpp_bare_name");
        m->add(fun(&Type_Info::bare_equal), "bare_equal");
        typedef bool (Type_Info::*typeinfocompare)(const Type_Info &) const;
        m->add(fun(typeinfocompare(&Type_Info::operator==)), "==");
        m->add(fun(&Type_Info::bare_equal), "bare_equal");


        basic_constructors<bool>("bool", m);
        operators::assign<bool>(m);
        operators::equal<bool>(m);

        m->add(fun(&to_string<const std::string &>), "internal_to_string");
        m->add(fun(&Bootstrap::bool_to_string), "internal_to_string");
        m->add(fun(&unknown_assign), "=");
        m->add(fun(&throw_exception), "throw");
        m->add(fun(&what), "what");

        bootstrap_pod_type<double>("double", m);
        bootstrap_pod_type<long double>("long_double", m);
        bootstrap_pod_type<float>("float", m);
        bootstrap_pod_type<int>("int", m);
        bootstrap_pod_type<unsigned int>("unsigned_int", m);
        bootstrap_pod_type<unsigned long>("unsigned_long", m);
        bootstrap_pod_type<size_t>("size_t", m);
        bootstrap_pod_type<char>("char", m);
        bootstrap_pod_type<std::int8_t>("int8_t", m);
        bootstrap_pod_type<std::int16_t>("int16_t", m);
        bootstrap_pod_type<std::int32_t>("int32_t", m);
        bootstrap_pod_type<std::int64_t>("int64_t", m);
        bootstrap_pod_type<std::uint8_t>("uint8_t", m);
        bootstrap_pod_type<std::uint16_t>("uint16_t", m);
        bootstrap_pod_type<std::uint32_t>("uint32_t", m);
        bootstrap_pod_type<std::uint64_t>("uint64_t", m);

        operators::logical_compliment<bool>(m);

        opers_arithmetic_pod(m);


        m->add(fun(&print), "print_string");
        m->add(fun(&println), "println_string");

        m->add(Proxy_Function(new dispatch::Dynamic_Proxy_Function(std::bind(&bind_function, std::placeholders::_1))), 
          "bind");

        m->add(fun(&shared_ptr_unconst_clone<dispatch::Proxy_Function_Base>), "clone");
        m->add(fun(&ptr_assign<std::remove_const<dispatch::Proxy_Function_Base>::type>), "=");
        m->add(fun(&ptr_assign<std::add_const<dispatch::Proxy_Function_Base>::type>), "=");

        m->add(Proxy_Function(new dispatch::Dynamic_Proxy_Function(std::bind(&call_exists, std::placeholders::_1))), 
          "call_exists");

        m->add(fun(&Boxed_Value::type_match), "type_match");

        return m;
      }
    };
  }
}

#endif