// g2o - General Graph Optimization
// Copyright (C) 2011 R. Kuemmerle, G. Grisetti, W. Burgard
// All rights reserved.
//
// Redistribution and use in source and binary forms, with or without
// modification, are permitted provided that the following conditions are
// met:
//
// * Redistributions of source code must retain the above copyright notice,
//   this list of conditions and the following disclaimer.
// * Redistributions in binary form must reproduce the above copyright
//   notice, this list of conditions and the following disclaimer in the
//   documentation and/or other materials provided with the distribution.
//
// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS
// IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
// TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A
// PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
// HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED
// TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
// PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
// LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
// NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
// SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

#ifndef G2O_SIMULATOR_H
#define G2O_SIMULATOR_H

#include <map>
#include <vector>

#include "g2o_tutorial_slam2d_api.h"
#include "se2.h"

namespace g2o {
namespace tutorial {

class G2O_TUTORIAL_SLAM2D_API Simulator {
 public:
  enum G2O_TUTORIAL_SLAM2D_API MotionType { MO_LEFT, MO_RIGHT, MO_NUM_ELEMS };

  /**
   * \brief simulated landmark
   */
  struct G2O_TUTORIAL_SLAM2D_API Landmark {
    EIGEN_MAKE_ALIGNED_OPERATOR_NEW;
    int id;
    Eigen::Vector2d truePose;
    Eigen::Vector2d simulatedPose;
    std::vector<int> seenBy;
    Landmark() : id(-1) {}
  };
  using LandmarkVector = std::vector<Landmark>;
  using LandmarkPtrVector = std::vector<Landmark*>;

  /**
   * simulated pose of the robot
   */
  struct G2O_TUTORIAL_SLAM2D_API GridPose {
    EIGEN_MAKE_ALIGNED_OPERATOR_NEW;
    int id;
    SE2 truePose;
    SE2 simulatorPose;
    LandmarkPtrVector landmarks;  ///< the landmarks observed by this node
  };
  using PosesVector = std::vector<GridPose>;

  /**
   * \brief odometry constraint
   */
  struct G2O_TUTORIAL_SLAM2D_API GridEdge {
    int from;
    int to;
    SE2 trueTransf;
    SE2 simulatorTransf;
    Eigen::Matrix3d information;
    EIGEN_MAKE_ALIGNED_OPERATOR_NEW;
  };
  using GridEdgeVector = std::vector<GridEdge>;

  struct G2O_TUTORIAL_SLAM2D_API LandmarkEdge {
    int from;
    int to;
    Eigen::Vector2d trueMeas;
    Eigen::Vector2d simulatorMeas;
    Eigen::Matrix2d information;
    EIGEN_MAKE_ALIGNED_OPERATOR_NEW;
  };
  using LandmarkEdgeVector = std::vector<LandmarkEdge>;

 public:
  Simulator();
  ~Simulator();

  void simulate(int numPoses, const SE2& sensorOffset = SE2());

  const PosesVector& poses() const { return _poses; }
  const LandmarkVector& landmarks() const { return _landmarks; }
  const GridEdgeVector& odometry() const { return _odometry; }
  const LandmarkEdgeVector& landmarkObservations() const {
    return _landmarkObservations;
  }

 protected:
  PosesVector _poses;
  LandmarkVector _landmarks;
  GridEdgeVector _odometry;
  LandmarkEdgeVector _landmarkObservations;

  GridPose generateNewPose(const GridPose& prev, const SE2& trueMotion,
                           const Eigen::Vector2d& transNoise, double rotNoise);
  SE2 getMotion(int motionDirection, double stepLen);
  SE2 sampleTransformation(const SE2& trueMotion_,
                           const Eigen::Vector2d& transNoise, double rotNoise);
};

}  // namespace tutorial
}  // namespace g2o

#endif
