#pragma once

#include <QVariant>
#include <QList>

#include <vector>

namespace caf
{

template <typename T> class PdmDataValueField;
class PdmOptionItemInfo;
class PdmObjectHandle;

//==================================================================================================
/// A proxy class that implements the Gui interface of fields
///
/// This class collects methods that need specialization when introducing a new type in a PdmField.
/// Having those methods in a separate class makes it possible to "partially specialize" the methods
/// for container classes etc. since partial specialization of template functions is not C++ as of yet.
///
/// When introducing a new type in a PdmField, you might need to implement a (partial)specialization 
/// of this class.
//==================================================================================================

template <typename T>
class PdmUiFieldSpecialization
{
public:
    /// Convert the field value into a QVariant
    static QVariant convert(const T& value)
    {
        return QVariant::fromValue(value);
    }

    /// Set the field value from a QVariant
    static void setFromVariant(const QVariant& variantValue, T& value)
    {
        value = variantValue.value<T>();
    }

    /// Check equality between QVariants that carries a Field Value. 
    /// The == operator will normally work, but does not support custom types in the QVariant 
    /// See http://qt-project.org/doc/qt-4.8/qvariant.html#operator-eq-eq-64
    /// This is needed for the lookup regarding OptionValues
    static bool isEqual(const QVariant& variantValue, const QVariant& variantValue2)
    {
        return variantValue == variantValue2; 
    }

    /// Methods to get a list of options for a field, specialized for AppEnum
    static QList<PdmOptionItemInfo> valueOptions( bool* useOptionsOnly, const T& )
    {
        return QList<PdmOptionItemInfo>();
    }

    /// Methods to retrieve the possible PdmObject pointed to by a field
    static void childObjects(const PdmDataValueField<T>& , std::vector<PdmObjectHandle*>* )    
    { }
  
};
} // End of namespace caf

#include "cafInternalPdmFieldTypeSpecializations.h"