///////////////////////////////////////////////////////////////////////////////

// BSD 3-Clause License

//

// Copyright (C) 2021-2022, LAAS-CNRS, University of Edinburgh, INRIA

// Copyright note valid unless otherwise stated in individual files.

// All rights reserved.

///////////////////////////////////////////////////////////////////////////////

#ifndef CROCODDYL_MULTIBODY_RESIDUALS_PAIR_COLLISION_HPP_

#define CROCODDYL_MULTIBODY_RESIDUALS_PAIR_COLLISION_HPP_

#ifdef PINOCCHIO_WITH_HPP_FCL

#include <pinocchio/multibody/geometry.hpp>

#include "crocoddyl/core/residual-base.hpp"

#include "crocoddyl/multibody/data/multibody.hpp"

#include "crocoddyl/multibody/states/multibody.hpp"

namespace crocoddyl {

/**

 * @brief Pair collision residual

 *

 * This residual function defines the euclidean distance between a geometric

 * collision pair as \f$\mathbf{r}=\mathbf{p}_1-\mathbf{p}_2^*\f$, where

 * \f$\mathbf{p}_1,\mathbf{p}_2^*\in~\mathbb{R}^3\f$ are the nearest points on

 * each collision object with respect to the other object. One of the objects is

 * a body frame of the robot, the other is an external object. Note that for the

 * sake of fast computation, it is easier to define the collision objects as

 * inflated capsules. Note also that the dimension of the residual vector is

 * obtained from 3. Furthermore, the Jacobians of the residual function are

 * computed analytically.

 *

 * As described in `ResidualModelAbstractTpl()`, the residual value and its

 * Jacobians are calculated by `calc` and `calcDiff`, respectively.

 *

 * \sa `ResidualModelAbstractTpl`, `calc()`, `calcDiff()`, `createData()`

 */

template <typename _Scalar>

class ResidualModelPairCollisionTpl : public ResidualModelAbstractTpl<_Scalar> {

 public:

  typedef _Scalar Scalar;

  typedef MathBaseTpl<Scalar> MathBase;

  typedef ResidualModelAbstractTpl<Scalar> Base;

  typedef ResidualDataPairCollisionTpl<Scalar> Data;

  typedef ResidualDataAbstractTpl<Scalar> ResidualDataAbstract;

  typedef StateMultibodyTpl<Scalar> StateMultibody;

  typedef DataCollectorAbstractTpl<Scalar> DataCollectorAbstract;

  typedef pinocchio::GeometryModel GeometryModel;

  typedef typename MathBase::VectorXs VectorXs;

  typedef typename MathBase::MatrixXs MatrixXs;

  /**

   * @brief Initialize the pair collision residual model

   *

   * @param[in] state       State of the multibody system

   * @param[in] nu          Dimension of the control vector

   * @param[in] geom_model  Pinocchio geometry model containing the collision

   * pair

   * @param[in] pair_id     Index of the collision pair in the geometry model

   * @param[in] joint_id    Index of the nearest joint on which the collision

   * link is attached

   */

  ResidualModelPairCollisionTpl(boost::shared_ptr<StateMultibody> state,

                                const std::size_t nu,

                                boost::shared_ptr<GeometryModel> geom_model,

                                const pinocchio::PairIndex pair_id,

                                const pinocchio::JointIndex joint_id);

  virtual ~ResidualModelPairCollisionTpl();

  /**

   * @brief Compute the pair collision residual

   *

   * @param[in] data  Pair collision residual data

   * @param[in] x     State point \f$\mathbf{x}\in\mathbb{R}^{ndx}\f$

   * @param[in] u     Control input \f$\mathbf{u}\in\mathbb{R}^{nu}\f$

   */

  virtual void calc(const boost::shared_ptr<ResidualDataAbstract> &data,

                    const Eigen::Ref<const VectorXs> &x,

                    const Eigen::Ref<const VectorXs> &u);

  /**

   * @brief Compute the derivatives of the pair collision residual

   *

   * @param[in] data  Pair collision residual data

   * @param[in] x     State point \f$\mathbf{x}\in\mathbb{R}^{ndx}\f$

   * @param[in] u     Control input \f$\mathbf{u}\in\mathbb{R}^{nu}\f$

   */

  virtual void calcDiff(const boost::shared_ptr<ResidualDataAbstract> &data,

                        const Eigen::Ref<const VectorXs> &x,

                        const Eigen::Ref<const VectorXs> &u);

  virtual boost::shared_ptr<ResidualDataAbstract> createData(

      DataCollectorAbstract *const data);

  /**

   * @brief Return the Pinocchio geometry model

   */

  const pinocchio::GeometryModel &get_geometry() const;

  /**

   * @brief Return the reference collision pair id

   */

  pinocchio::PairIndex get_pair_id() const;

  /**

   * @brief Modify the reference collision pair id

   */

  void set_pair_id(const pinocchio::PairIndex pair_id);

 protected:

  using Base::nu_;

  using Base::state_;

  using Base::v_dependent_;

 private:

  typename StateMultibody::PinocchioModel

      pin_model_;  //!< Pinocchio model used for internal computations

  boost::shared_ptr<pinocchio::GeometryModel>

      geom_model_;  //!< Pinocchio geometry model containing collision pair

  pinocchio::PairIndex

      pair_id_;  //!< Index of the collision pair in geometry model

  pinocchio::JointIndex joint_id_;  //!< Index of joint on which the collision

                                    //!< body frame of the robot is attached

};

template <typename _Scalar>

struct ResidualDataPairCollisionTpl : public ResidualDataAbstractTpl<_Scalar> {

  typedef _Scalar Scalar;

  typedef MathBaseTpl<Scalar> MathBase;

  typedef ResidualDataAbstractTpl<Scalar> Base;

  typedef StateMultibodyTpl<Scalar> StateMultibody;

  typedef DataCollectorAbstractTpl<Scalar> DataCollectorAbstract;

  typedef typename MathBase::Matrix6xs Matrix6xs;

  typedef typename MathBase::Vector3s Vector3s;

  template <template <typename Scalar> class Model>

                               DataCollectorAbstract *const data)

      : Base(model, data),

        geometry(pinocchio::GeometryData(model->get_geometry())),

    // Check that proper shared data has been passed

          "Invalid argument: the shared data should be derived from "

          "DataCollectorActMultibodyTpl");

    }

    // Avoids data casting at runtime

  pinocchio::GeometryData geometry;       //!< Pinocchio geometry data

  pinocchio::DataTpl<Scalar> *pinocchio;  //!< Pinocchio data

  Matrix6xs J;                            //!< Jacobian at the collision joint

  Vector3s d;  //!< Vector from joint point to collision point in world frame

  using Base::r;

  using Base::Ru;

  using Base::Rx;

  using Base::shared;

};

}  // namespace crocoddyl

/* --- Details -------------------------------------------------------------- */

/* --- Details -------------------------------------------------------------- */

/* --- Details -------------------------------------------------------------- */

#include "crocoddyl/multibody/residuals/pair-collision.hxx"

#endif  // PINOCCHIO_WITH_HPP_FCL

#endif  // CROCODDYL_MULTIBODY_RESIDUALS_PAIR_COLLISION_HPP_