validator.h

/*
    Evocosm is a C++ framework for implementing evolutionary algorithms.

    Copyright 2011 Scott Robert Ladd. All rights reserved.

    Evocosm is user-supported open source software. Its continued development is dependent
    on financial support from the community. You can provide funding by visiting the Evocosm
    website at:

        http://www.coyotegulch.com

    You may license Evocosm in one of two fashions:

    1) Simplified BSD License (FreeBSD License)

    Redistribution and use in source and binary forms, with or without modification, are
    permitted provided that the following conditions are met:

    1.  Redistributions of source code must retain the above copyright notice, this list of
        conditions and the following disclaimer.

    2.  Redistributions in binary form must reproduce the above copyright notice, this list
        of conditions and the following disclaimer in the documentation and/or other materials
        provided with the distribution.

    THIS SOFTWARE IS PROVIDED BY SCOTT ROBERT LADD ``AS IS'' AND ANY EXPRESS OR IMPLIED
    WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
    FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL SCOTT ROBERT LADD OR
    CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
    CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
    SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
    ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
    NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
    ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

    The views and conclusions contained in the software and documentation are those of the
    authors and should not be interpreted as representing official policies, either expressed
    or implied, of Scott Robert Ladd.

    2) Closed-Source Proprietary License

    If your project is a closed-source or proprietary project, the Simplified BSD License may
    not be appropriate or desirable. In such cases, contact the Evocosm copyright holder to
    arrange your purchase of an appropriate license.

    The author can be contacted at:

          scott.ladd@coyotegulch.com
          scott.ladd@gmail.com
          http:www.coyotegulch.com
*/

#if !defined(LIBEVOCOSM_VALIDATOR_H)
#define LIBEVOCOSM_VALIDATOR_H

#include <sstream>
#include <stdexcept>
#include <typeinfo>

namespace libevocosm
{
    using std::stringstream;
    using std::string;
    using std::runtime_error;


    template <typename Type>
    class validation_error : public runtime_error
    {
    private:
        static string build_error_string(const Type & object,
                                         const string & details)
        {
            stringstream message;

            message << "validation error: "
                    << typeid(object).name() << " " << object
                    << details;

            return message.str();
        }

    public:

        validation_error(const Type & object,
                         const string & details = string())
            : runtime_error(build_error_string(object,details))
        {
            // nada
        }
    };


    template <typename Type>
    void validate_equals(const Type & object,
                         const Type & constraint,
                         const string & message = string())
    {
        if (object != constraint)
        {
            stringstream details;
            details << " must equal " << constraint << " " << message;
            throw validation_error<Type>(object,details.str());
        }
    }


    template <typename Type>
    void validate_not(const Type & object,
                      const Type & constraint,
                      const string & message = string())
    {
        if (object == constraint)
        {
            stringstream details;
            details << " must not equal " << constraint << " " << message;
            throw validation_error<Type>(object,details.str());
        }
    }


    template <typename Type>
    void validate_less(const Type & object,
                      const Type & constraint,
                      const string & message = string())
    {
        if (object >= constraint)
        {
            stringstream details;
            details << " must be less than " << constraint << " " << message;
            throw validation_error<Type>(object,details.str());
        }
    }


    template <typename Type>
    void validate_less_eq(const Type & object,
                          const Type & constraint,
                          const string & message = string())
    {
        if (object > constraint)
        {
            stringstream details;
            details << " must be less than " << constraint << " " << message;
            throw validation_error<Type>(object,details.str());
        }
    }


    template <typename Type>
    void validate_greater(const Type & object,
                      const Type & constraint,
                      const string & message = string())
    {
        if (object <= constraint)
        {
            stringstream details;
            details << " must be greater than " << constraint << " " << message;
            throw validation_error<Type>(object,details.str());
        }
    }


    template <typename Type>
    void validate_greater_eq(const Type & object,
                      const Type & constraint,
                      const string & message = string())
    {
        if (object < constraint)
        {
            stringstream details;
            details << " must be greater than " << constraint << " " << message;
            throw validation_error<Type>(object,details.str());
        }
    }


    template <typename Type>
    void validate_range(const Type & object,
                        const Type & low_bound,
                        const Type & high_bound,
                        const string & message = string())
    {
        if ((object < low_bound) || (object > high_bound))
        {
            stringstream details;
            details << " must be between " << low_bound << " and "
                    << high_bound << " " << message;
            throw validation_error<Type>(object,details.str());
        }
    }


    template <typename Type, typename Predicate>
    void validate_with(const Type & object,
                       const Predicate & constraint,
                       const string & message = string())
    {
        if (!constraint(object))
        {
            stringstream details;
            details << " failed test " << typeid(constraint).name() << " " << message;
            throw validation_error<Type>(object,details.str());
        }
    }


    template <typename Type>
    void enforce_lower_limit(Type & object,
                             const Type & low_value)
    {
        if (object < low_value)
            object = low_value;
    }


    template <typename Type>
    void enforce_upper_limit(Type & object,
                            const Type & high_value)
    {
        if (object > high_value)
            object = high_value;
    }


    template <typename Type>
    void enforce_index(Type & object,
                        const Type & array_length)
    {
        if (object >= array_length)
            object = array_length - 1;

        if (object < 0)
            object = 0;
    }


    template <typename Type>
    void enforce_range(Type & object,
                       const Type & low_value,
                       const Type & high_value)
    {
        if (object < low_value)
            object = low_value;
        else if (object > high_value)
            object = high_value;
    }


    inline string build_location_string(const char * filename, long line_no)
    {
        stringstream text;
        text << "in " << filename << ", line " << line_no;
        return text.str();
    }
}

// These macros allow validation to be included on a per-compile basis, based on the settings
// of the DEBUG and NDEBUG preprocessor macros.
#if defined(_DEBUG) && !defined(NDEBUG)
#define LIBEVOCOSM_VALIDATE_EQUALS(object,constraint,details) libevocosm::validate_equals(object,constraint,details)
#define LIBEVOCOSM_VALIDATE_NOT(object,constraint,details) libevocosm::validate_not(object,constraint,details)
#define LIBEVOCOSM_VALIDATE_LESS(object,constraint,details) libevocosm::validate_less(object,constraint,details)
#define LIBEVOCOSM_VALIDATE_LESS_EQ(object,constraint,details) libevocosm::validate_less_eq(object,constraint,details)
#define LIBEVOCOSM_VALIDATE_GREATER(object,constraint,details) libevocosm::validate_greater(object,constraint,details)
#define LIBEVOCOSM_VALIDATE_GREATER_EQ(object,constraint,details) libevocosm::validate_greater_eq(object,constraint,details)
#define LIBEVOCOSM_VALIDATE_RANGE(object,low_bound,high_bound,details) libevocosm::validate_range(object,low_bound,high_bound,details)
#define LIBEVOCOSM_VALIDATE_WITH(object,constraint,details) libevocosm::validate_with(object,constraint,details)
#define LIBEVOCOSM_LOCATION libevocosm::build_location_string(__FILE__,__LINE__)
#else
#define LIBEVOCOSM_VALIDATE_EQUALS(object,constraint,details)
#define LIBEVOCOSM_VALIDATE_NOT(object,constraint,details)
#define LIBEVOCOSM_VALIDATE_LESS(object,constraint,details)
#define LIBEVOCOSM_VALIDATE_LESS_EQ(object,constraint,details)
#define LIBEVOCOSM_VALIDATE_GREATER(object,constraint,details)
#define LIBEVOCOSM_VALIDATE_GREATER_EQ(object,constraint,details)
#define LIBEVOCOSM_VALIDATE_RANGE(object,low_bound,high_bound,details)
#define LIBEVOCOSM_VALIDATE_WITH(object,constraint,details)
#define LIBEVOCOSM_LOCATION std::string()
#endif

#endif