Property.hpp

/***************************************************************************
  tag: Peter Soetens  Mon Jan 19 14:11:19 CET 2004  Property.hpp

                        Property.hpp -  description
                           -------------------
    begin                : Mon January 19 2004
    copyright            : (C) 2004 Peter Soetens
    email                : peter.soetens@mech.kuleuven.ac.be

 ***************************************************************************
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#ifndef ORO_PROPERTY_HPP
#define ORO_PROPERTY_HPP

#include "rtt-config.h"
#include "base/PropertyBase.hpp"
#include "PropertyBag.hpp"
#include "internal/DataSources.hpp"
#include <boost/type_traits/remove_const.hpp>
#include <boost/call_traits.hpp>
#include "Logger.hpp"

#include <string>
#include <ostream>

#ifdef ORO_PRAGMA_INTERFACE
#pragma interface
#endif

namespace RTT
{
    template<typename T>
    class Property
        : public base::PropertyBase
    {
    public:
        typedef typename boost::remove_const<typename boost::remove_reference<T>::type>::type value_t;
        typedef typename boost::call_traits<value_t>::param_type param_t;
        typedef typename boost::call_traits<value_t>::reference reference_t;
        typedef typename boost::call_traits<value_t>::const_reference const_reference_t;
        typedef value_t DataSourceType;

        Property()
        {}

        explicit Property(const std::string& name)
            : base::PropertyBase(name,""), _value( new internal::ValueDataSource<value_t>() )
        {
        }

        Property(const std::string& name, const std::string& description, param_t value = value_t() )
            : base::PropertyBase(name, description), _value( new internal::ValueDataSource<value_t>( value ) )
        {
        }

        Property( const Property<T>& orig)
            : base::PropertyBase(orig.getName(), orig.getDescription()),
              _value( orig._value ? orig._value->clone() : 0 )
        {
            // need to do this on the clone() in order to have access to set()/rvalue() of the data source.
            if (_value)
                _value->evaluate();
        }

        Property( base::PropertyBase* source)
            : base::PropertyBase(source ? source->getName() : "", source ? source->getDescription() : ""),
              _value( source ? internal::AssignableDataSource<DataSourceType>::narrow(source->getDataSource().get() ) : 0 )
        {
            if ( source && ! _value ) {
                log(Error) <<"Can not initialize Property from "<<source->getName() <<": ";
                if ( source->getDataSource() )
                    log() << "incompatible type ( destination type: "<< getType() << ", source type: "<< source->getDataSource()->getTypeName() << ")."<<endlog();
                else
                    log() << "source Property was not ready."<<endlog();
            }
        }

        Property(const std::string& name, const std::string& description,
                 typename internal::AssignableDataSource<DataSourceType>::shared_ptr datasource )
            : base::PropertyBase(name, description), _value( datasource )
        {
            // need to do this on the datasource in order to have access to set()/rvalue() of the data source.
            if (_value)
                _value->evaluate();
        }

        Property<T>& operator=( param_t value )
        {
            _value->set( value );
            return *this;
        }

        Property<T>& operator=( base::PropertyBase* source )
        {
            if ( this == source )
                return *this;

            if ( source ) {
                this->setName( source->getName() );
                this->setDescription( source->getDescription() );
                typename internal::AssignableDataSource<DataSourceType>::shared_ptr vptr
                    = internal::AssignableDataSource<DataSourceType>::narrow(source->getDataSource().get() );
                if (vptr) {
                    _value = vptr;
                    return *this;
                }
            }
            // wrong assignment: mark not ready.
            this->setName( "" );
            this->setDescription( "" );
            _value = 0;
            return *this;
        }

        Property<T>& operator<<=(Property<T> &p)
        {
            this->update( p );
            return *this;
        }

        Property<T>& doc(const std::string& descr) {
            setDescription(descr);
            return *this;
        }

        operator value_t() const
        {
            return _value->get();
        }

        DataSourceType get() const
        {
            return _value->get();
        }

        reference_t set()
        {
            return _value->set();
        }

        void set(param_t v)
        {
            _value->set(v);
        }

        reference_t value()
        {
            return set();
        }

        const_reference_t rvalue() const
        {
            return _value->rvalue();
        }

        static Property<T>* narrow( base::PropertyBase* prop );

        virtual void identify( base::PropertyIntrospection* pi);

        virtual void identify( base::PropertyBagVisitor* pi);

        virtual bool update( const base::PropertyBase* other)
        {
            const Property<T>* origin = dynamic_cast< const Property<T>* >( other );
            if ( origin != 0 ) {
                return this->update( *origin );
            }
            return false;
        }

        virtual bool refresh( const base::PropertyBase* other)
        {
            const Property<T>* origin = dynamic_cast< const Property<T>* >( other );
            if ( origin != 0 && _value ) {
                return this->refresh( *origin );
            }
            return false;
        }

        virtual bool copy( const base::PropertyBase* other )
        {
            const Property<T>* origin = dynamic_cast< const Property<T>* >( other );
            if ( origin != 0 && _value ) {
                return this->copy( *origin );
            }
            return false;
        }

        bool copy( const Property<T>& orig)
        {
            if ( !ready() )
                return false;
            _description = orig.getDescription();
            _name = orig.getName();
            _value->set( orig.rvalue() );
            return true;
        }

        bool update( const Property<T>& orig)
        {
            if ( !ready() )
                return false;
            if ( _description.empty() )
                _description = orig.getDescription();
            _value->set( orig.rvalue() );
            return true;
        }

        bool refresh( const Property<T>& orig)
        {
            if ( !ready() )
                return false;
            _value->set( orig.rvalue() );
            return true;
        }

        virtual Property<T>* clone() const
        {
            return new Property<T>(*this);
        }

        virtual Property<T>* create() const
        {
            return new Property<T>( _name, _description, T() );
        }

        virtual base::DataSourceBase::shared_ptr getDataSource() const {
            return _value;
        }

        typename internal::AssignableDataSource<DataSourceType>::shared_ptr getAssignableDataSource() const {
            return _value;
        }

        virtual std::string getType() const {
            return internal::DataSource<T>::GetType();
        }

        virtual const types::TypeInfo* getTypeInfo() const {
            return internal::DataSource<T>::GetTypeInfo();
        }
    protected:
        typename internal::AssignableDataSource<DataSourceType>::shared_ptr _value;
    };


    template<>
    RTT_API bool Property<PropertyBag>::update( const Property<PropertyBag>& orig);

    template<>
    RTT_API bool Property<PropertyBag>::refresh( const Property<PropertyBag>& orig);

    template<>
    RTT_API bool Property<PropertyBag>::copy( const Property<PropertyBag>& orig);

    template<typename T>
    std::ostream& operator<<(std::ostream &os, Property<T> &p)
    {
#ifdef OS_HAVE_STREAMS
        os << p.getDataSource();
#endif
        return os;
    }

    template<class T>
    Property<T>* Property<T>::narrow( base::PropertyBase* prop ) {
        Property<T>* res = dynamic_cast<Property<T>*>( prop );
        return res;
    }
}

#include "base/PropertyIntrospection.hpp"

namespace RTT
{
    template< class T>
    void Property<T>::identify( base::PropertyIntrospection* pi)
    {
        pi->introspect( *this );
    }

    template< class T>
    void Property<T>::identify( base::PropertyBagVisitor* pi)
    {
        return base::PropertyBase::identify(pi);
    }

    template<>
    RTT_API void Property<PropertyBag>::identify( base::PropertyBagVisitor* pbi);
}

#endif