single_input.h

// Description: Scalar input
// Documentation: input.txt

#ifndef PASTELSYS_SCALAR_INPUT_H
#define PASTELSYS_SCALAR_INPUT_H

#include "pastel/sys/input/input_concept.h"

namespace Pastel
{

    template <typename Type>
    class Scalar_Input
    {
    public:
        Scalar_Input()
        : data_()
        , n_(1)
        {
        }

        explicit Scalar_Input(Type data, integer n = 1)
        : data_(std::move(data))
        , n_(n)
        {
            PENSURE_OP(n, >=, 0);
        }

        integer nHint() const
        {
            return n_;
        }

        integer n() const
        {
            return nHint();
        }

        bool empty() const
        {
            return n_ == 0;
        }

        const Type& get() const
        {
            PENSURE(!empty());
            return data_;
        }

        const Type& operator[](integer i) const
        {
            PENSURE_OP(i, >=, 0);
            PENSURE_OP(i, <, n());
            return data_;
        }

        void pop()
        {
            PENSURE(!empty());
            --n_;
        }

    private:
        Type data_;
        integer n_;
    };

    template <typename Type>
    Scalar_Input<typename std::decay<Type>::type> scalarInput(Type&& that, integer n = 1)
    {
        return Scalar_Input<typename std::decay<Type>::type>(
            std::forward<Type>(that), n);
    }

}

#endif