#ifndef MULTI_BODY_TREE_CREATOR_HPP_
#define MULTI_BODY_TREE_CREATOR_HPP_

#include <string>
#include <vector>
#include "BulletInverseDynamics/IDConfig.hpp"
#include "BulletInverseDynamics/IDMath.hpp"
#include "BulletInverseDynamics/MultiBodyTree.hpp"
#include "MultiBodyNameMap.hpp"

namespace btInverseDynamics {
/// Interface class for initializing a MultiBodyTree instance.
/// Data to be provided is modeled on the URDF specification.
/// The user can derive from this class in order to programmatically
/// initialize a system.
class MultiBodyTreeCreator {
public:
    /// the dtor
    virtual ~MultiBodyTreeCreator() {}
    /// Get the number of bodies in the system
    /// @param num_bodies write number of bodies here
    /// @return 0 on success, -1 on error
    virtual int getNumBodies(int* num_bodies) const = 0;
    /// Interface for accessing link mass properties.
    /// For detailed description of data, @sa MultiBodyTree::addBody
    /// \copydoc MultiBodyTree::addBody
    virtual int getBody(const int body_index, int* parent_index, JointType* joint_type,
                        vec3* parent_r_parent_body_ref, mat33* body_T_parent_ref,
                        vec3* body_axis_of_motion, idScalar* mass, vec3* body_r_body_com,
                        mat33* body_I_body, int* user_int, void** user_ptr) const = 0;
    /// @return a pointer to a name mapping utility class, or 0x0 if not available
    virtual const MultiBodyNameMap* getNameMap() const {return 0x0;}
};

/// Create a multibody object.
/// @param creator an object implementing the MultiBodyTreeCreator interface
///        that returns data defining the system
/// @return A pointer to an allocated multibodytree instance, or
///         0x0 if an error occured.
MultiBodyTree* CreateMultiBodyTree(const MultiBodyTreeCreator& creator);
}

// does urdf have gravity direction ??

#endif  // MULTI_BODY_TREE_CREATOR_HPP_