/*
 * Copyright (C) 2012 Open Source Robotics Foundation
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 *
*/
#ifndef GZ_MATH_ROTATIONSPLINE_HH_
#define GZ_MATH_ROTATIONSPLINE_HH_

#include <gz/math/Quaternion.hh>
#include <gz/math/config.hh>
#include <gz/utils/ImplPtr.hh>

namespace gz::math
{
  // Inline bracket to help doxygen filtering.
  inline namespace GZ_MATH_VERSION_NAMESPACE {
  /// \class RotationSpline RotationSpline.hh gz/math/RotationSpline.hh
  /// \brief Spline for rotations
  class GZ_MATH_VISIBLE  RotationSpline
  {
    /// \brief Constructor. Sets the autoCalc to true
    public: RotationSpline();

    /// \brief Adds a control point to the end of the spline.
    /// \param[in] _p control point
    public: void AddPoint(const Quaterniond &_p);

    /// \brief Gets the detail of one of the control points of the spline.
    /// \param[in] _index the index of the control point. _index is
    /// clamped to [0, PointCount()-1].
    /// \remarks This point must already exist in the spline.
    /// \return The quaternion at the specified point.
    /// If there are no points, then a Quaterniond with a value of
    /// [INF, INF, INF, INF] is returned.
    public: const Quaterniond &Point(const unsigned int _index) const;

    /// \brief Gets the number of control points in the spline.
    /// \return the count
    public: unsigned int PointCount() const;

    /// \brief Clears all the points in the spline.
    public: void Clear();

    /// \brief Updates a single point in the spline.
    /// \remarks This point must already exist in the spline.
    /// \param[in] _index index
    /// \param[in] _value the new control point value
    /// \return True on success, false if _index is larger or equal than
    /// PointCount().
    public: bool UpdatePoint(const unsigned int _index,
                             const Quaterniond &_value);

    /// \brief Returns an interpolated point based on a parametric
    ///        value over the whole series.
    /// \remarks Given a t value between 0 and 1 representing the
    ///          parametric distance along the whole length of the spline,
    ///          this method returns an interpolated point.
    /// \param[in] _t Parametric value.
    /// \param[in] _useShortestPath Defines if rotation should take the
    ///        shortest possible path
    /// \return The rotation, or [INF, INF, INF, INF] on error. Use
    /// Quateriond::IsFinite() to check for an error
    public: Quaterniond Interpolate(double _t,
                                    const bool _useShortestPath = true);

    /// \brief Interpolates a single segment of the spline
    ///        given a parametric value.
    /// \param[in] _fromIndex The point index to treat as t = 0.
    ///        _fromIndex + 1 is deemed to be t = 1
    /// \param[in] _t Parametric value
    /// \param[in] _useShortestPath Defines if rotation should take the
    ///         shortest possible path
    /// \return the rotation, or [INF, INF, INF, INF] on error. Use
    /// Quateriond::IsFinite() to check for an error
    public: Quaterniond Interpolate(const unsigned int _fromIndex,
                const double _t, const bool _useShortestPath = true);

    /// \brief Tells the spline whether it should automatically calculate
    ///        tangents on demand as points are added.
    /// \remarks The spline calculates tangents at each point automatically
    ///          based on the input points.  Normally it does this every
    ///          time a point changes. However, if you have a lot of points
    ///          to add in one go, you probably don't want to incur this
    ///          overhead and would prefer to defer the calculation until
    ///          you are finished setting all the points. You can do this
    ///          by calling this method with a parameter of 'false'. Just
    ///          remember to manually call the recalcTangents method when
    ///          you are done.
    /// \param[in] _autoCalc If true, tangents are calculated for you
    /// whenever a point changes. If false, you must call reclacTangents to
    /// recalculate them when it best suits.
    public: void AutoCalculate(bool _autoCalc);

    /// \brief Recalculates the tangents associated with this spline.
    /// \remarks If you tell the spline not to update on demand by calling
    /// setAutoCalculate(false) then you must call this after
    /// completing your updates to the spline points.
    public: void RecalcTangents();

    /// \brief Private data pointer
    GZ_UTILS_IMPL_PTR(dataPtr)
  };
  }  // namespace GZ_MATH_VERSION_NAMESPACE
}  // namespace gz::math
#endif  // GZ_MATH_ROTATIONSPLINE_HH_
