//          Copyright Joakim Karlsson & Kim Gräsman 2010-2012.
// 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)

#ifndef SNOWHOUSE_STARTSWITHCONSTRAINT_H
#define SNOWHOUSE_STARTSWITHCONSTRAINT_H

#include "expressions/expression.h"

namespace snowhouse
{
    template <typename ExpectedType>
    struct StartsWithConstraint : Expression<StartsWithConstraint<ExpectedType>>
    {
        StartsWithConstraint(const ExpectedType& expected): m_expected(expected)
        {
        }

        bool operator()(const std::string& actual) const
        {
            return actual.find(m_expected) == 0;
        }

        ExpectedType m_expected;
    };

    template <typename ExpectedType>
    inline StartsWithConstraint<ExpectedType> StartsWith(
        const ExpectedType& expected)
    {
        return StartsWithConstraint<ExpectedType>(expected);
    }

    inline StartsWithConstraint<std::string> StartsWith(const char* expected)
    {
        return StartsWithConstraint<std::string>(expected);
    }

    template <typename ExpectedType>
    struct Stringizer<StartsWithConstraint<ExpectedType>>
    {
        static std::string ToString(
            const StartsWithConstraint<ExpectedType>& constraint)
        {
            std::ostringstream builder;
            builder << "starts with "
                    << snowhouse::Stringize(constraint.m_expected);

            return builder.str();
        }
    };
}

#endif
