// Copyright  (C)  2007  Ruben Smits <ruben dot smits at intermodalics dot eu>

// Version: 1.0
// Author: Ruben Smits <ruben dot smits at intermodalics dot eu>
// Maintainer: Ruben Smits <ruben dot smits at intermodalics dot eu>
// URL: http://www.orocos.org/kdl

// This library is free software; you can redistribute it and/or
// modify it under the terms of the GNU Lesser General Public
// License as published by the Free Software Foundation; either
// version 2.1 of the License, or (at your option) any later version.

// This library is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
// Lesser General Public License for more details.

// You should have received a copy of the GNU Lesser General Public
// License along with this library; if not, write to the Free Software
// Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA


#ifndef KDL_SEGMENT_HPP
#define KDL_SEGMENT_HPP

#include "frames.hpp"
#include "rigidbodyinertia.hpp"
#include "joint.hpp"
#include <vector>

namespace KDL {

    /**
	  * \brief This class encapsulates a simple segment, that is a "rigid
	  * body" (i.e., a frame and a rigid body inertia) with a joint and with
	  * "handles", root and tip to connect to other segments.
     *
     * A simple segment is described by the following properties :
     *      - Joint
     *      - Rigid Body Inertia: of the rigid body part of the Segment
     *      - Offset from the end of the joint to the tip of the segment:
     *        the joint is located at the root of the segment.
     *
     * @ingroup KinematicFamily
     */
    class Segment {
        friend class Chain;
    private:
        std::string name;
        Joint joint;
        RigidBodyInertia I;
        Frame f_tip;

    public:
        /**
         * Constructor of the segment
         *
         * @param name name of the segment
         * @param joint joint of the segment, default:
         * Joint(Joint::Fixed)
         * @param f_tip frame from the end of the joint to the tip of
         * the segment, default: Frame::Identity()
         * @param M rigid body inertia of the segment, default: Inertia::Zero()
         */
        explicit Segment(const std::string& name, const Joint& joint=Joint(Joint::Fixed), const Frame& f_tip=Frame::Identity(),const RigidBodyInertia& I = RigidBodyInertia::Zero());
        /**
         * Constructor of the segment
         *
         * @param joint joint of the segment, default:
         * Joint(Joint::Fixed)
         * @param f_tip frame from the end of the joint to the tip of
         * the segment, default: Frame::Identity()
         * @param M rigid body inertia of the segment, default: Inertia::Zero()
         */
        explicit Segment(const Joint& joint=Joint(Joint::Fixed), const Frame& f_tip=Frame::Identity(),const RigidBodyInertia& I = RigidBodyInertia::Zero());
        Segment(const Segment& in);
        Segment& operator=(const Segment& arg);

        virtual ~Segment();

        /**
         * Request the pose of the segment, given the joint position q.
         *
         * @param q 1D position of the joint
         *
         * @return pose from the root to the tip of the segment
         */
        Frame pose(const double& q)const;
        /**
         * Request the 6D-velocity of the tip of the segment, given
         * the joint position q and the joint velocity qdot.
         *
         * @param q 1D position of the joint
         * @param qdot 1D velocity of the joint
         *
         * @return 6D-velocity of the tip of the segment, expressed
         *in the base-frame of the segment(root) and with the tip of
         *the segment as reference point.
         */
        Twist twist(const double& q,const double& qdot)const;

        /**
         * Request the name of the segment
         *
         *
         * @return const reference to the name of the segment
         */
        const std::string& getName()const
        {
            return name;
        }
        /**
         * Request the joint of the segment
         *
         *
         * @return const reference to the joint of the segment
         */
        const Joint& getJoint()const
        {
            return joint;
        }
        /**
         * Request the inertia of the segment
         *
         *
         * @return const reference to the inertia of the segment
         */
        const RigidBodyInertia& getInertia()const
        {
            return I;
        }
        /**
         * Request the inertia of the segment
         *
         *
         * @return const reference to the inertia of the segment
         */
        void setInertia(const RigidBodyInertia& Iin)
        {
            this->I=Iin;
        }

        /**
         * Request the pose from the joint end to the tip of the
         *segment.
         *
         * @return the original parent end - segment end pose.
         */
        Frame getFrameToTip()const
        {

            return joint.pose(0)*f_tip;
        }

        /**
         * Set the pose from the joint end to the tip of the
         * segment.
         *
         * @param f_tip_new pose from the joint end to the tip of the segment
         */
        void setFrameToTip(const Frame& f_tip_new);

        /**
         * Request the pose from the end of the joint to the tip of the segment
         * at joint position 0.
         * 
         * @return const reference to the pose from the end of the joint to the tip of the segment
         * at joint position 0
         */
        const Frame& getFrameToTipZero() const
        {
            return f_tip;
        }
    };
}//end of namespace KDL

#endif