/*=============================================================================
    Copyright (c) 2001-2014 Joel de Guzman

    Distributed under the Boost Software License, Version 1.0. (See accompanying
    file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
=============================================================================*/
#if !defined(BOOST_SPIRIT_X3_EXPECT_MARCH_16_2012_1024PM)
#define BOOST_SPIRIT_X3_EXPECT_MARCH_16_2012_1024PM

#include <boost/spirit/home/x3/support/context.hpp>
#include <boost/spirit/home/x3/core/parser.hpp>
#include <boost/spirit/home/x3/core/detail/parse_into_container.hpp>

#include <boost/config.hpp> // for BOOST_SYMBOL_VISIBLE
#include <boost/throw_exception.hpp>
#include <stdexcept>

namespace boost {
namespace spirit {
namespace x3 {
template <typename Iterator>
struct BOOST_SYMBOL_VISIBLE expectation_failure : std::runtime_error
{
  public:

    expectation_failure(Iterator where, std::string const& which)
        : std::runtime_error("boost::spirit::x3::expectation_failure")
        , where_(where), which_(which)
    {}
    ~expectation_failure() {}

    std::string
    which() const
    {
        return which_;
    }
    Iterator const&
    where() const
    {
        return where_;
    }

  private:

    Iterator where_;
    std::string which_;
};

template <typename Subject>
struct expect_directive : unary_parser<Subject, expect_directive<Subject>>
{
    typedef unary_parser<Subject, expect_directive<Subject> > base_type;
    static bool const is_pass_through_unary = true;

    constexpr
    expect_directive(Subject const& subject)
        : base_type(subject) {}

    template <typename Iterator, typename Context
              , typename RContext, typename Attribute>
    bool
    parse(Iterator& first, Iterator const& last
          , Context const& context, RContext& rcontext, Attribute& attr) const
    {
        bool r = this->subject.parse(first, last, context, rcontext, attr);

        if (!r)
        {
            boost::throw_exception(
                expectation_failure<Iterator>(
                    first, what(this->subject)));
        }

        return r;
    }
};

struct expect_gen
{
    template <typename Subject>
    constexpr expect_directive<typename extension::as_parser<Subject>::value_type>
    operator[](Subject const& subject) const
    {
        return { as_parser(subject) };
    }
};

constexpr auto expect = expect_gen{};
}
}
}

namespace boost {
namespace spirit {
namespace x3 {
namespace detail {
// Special case handling for expect expressions.
template <typename Subject, typename Context, typename RContext>
struct parse_into_container_impl<expect_directive<Subject>, Context, RContext>
{
    template <typename Iterator, typename Attribute>
    static bool
    call(
        expect_directive<Subject> const& parser
    , Iterator& first, Iterator const& last
    , Context const& context, RContext& rcontext, Attribute& attr)
    {
        bool r = parse_into_container(
                     parser.subject, first, last, context, rcontext, attr);

        if (!r)
        {
            boost::throw_exception(
                expectation_failure<Iterator>(
                    first, what(parser.subject)));
        }

        return r;
    }
};
}
}
}
}

#endif
