#ifndef __CONFIG_CONFIGURATION_H__
#define __CONFIG_CONFIGURATION_H__
/*
 *******************************************************************************
 *                                   INCLUDE
 *******************************************************************************
 */
#include <iostream>
#include <map>
#include <unordered_set>
#include "Poco/Any.h"
#include "Poco/Exception.h"
#include "Poco/Format.h"


namespace Util
{
/*
 *******************************************************************************
 *                                CLASS DECLARE
 *******************************************************************************
 */
class Configuration
{
private:
    class Parameter
    {
    public:
        template <class T> T getValue()
        {
            return Poco::AnyCast<T>(_value);
        }

        void setValue(const Poco::Any& value)
        {
            this->_value = value;
        }

        void setChanged(bool changed)
        {
            this->_changed = changed;
        }

        bool getChanged()
        {
            return _changed;
        }

        bool empty()
        {
            return _value.empty();
        }

        Poco::Any& value()
        {
            return _value;
        }

    private:
        Poco::Any _value;
        bool      _changed;
    };

public:
    class ParameterNames: public std::unordered_set<std::string>
    {
    public:
        bool exists(std::string name) const;
    };

public:
    virtual ~Configuration();

    template <class T> Configuration& setParameter(const std::string& name, const T& value)
    {
        Parameter& parameter = _parameters[name];
        if (parameter.empty() || parameter.getValue<T>() != value)
        {
            parameter.setChanged(true);
            parameter.setValue(value);
        }

        return *this;
    }

    template <class T> T getParameter(const std::string& name)
    {
        return findParameter(name).getValue<T>();
    }

    bool isParameterChanged(const std::string& name)
    {
        return findParameter(name).getChanged();
    }

    void confirmParameterChanged(const std::string& name)
    {
        findParameter(name).setChanged(false);
    }

    void getChangedParameters(ParameterNames& names)
    {
        names.clear();
        for (auto& p : _parameters)
        {
            if (p.second.getChanged())
                names.insert(p.first);
        }
    }

    const std::string& name() const
    {
        return _name;
    }

    void copyTo(Configuration& other);

protected:
    void setName(std::string& name)
    {
        _name = name;
    }

    Parameter& findParameter(const std::string& name)
    {
        if (_parameters.find(name) == _parameters.end())
            throw Poco::NotFoundException(Poco::format("Can't find parameter: %s", name), -ENODATA);

        return _parameters[name];
    }

private:
    using Parameters = std::map<std::string, Parameter>;

    Parameters  _parameters;
    std::string _name;
};

}
#endif