/* +------------------------------------------------------------------------+
   |                     Mobile Robot Programming Toolkit (MRPT)            |
   |                          https://www.mrpt.org/                         |
   |                                                                        |
   | Copyright (c) 2005-2024, Individual contributors, see AUTHORS file     |
   | See: https://www.mrpt.org/Authors - All rights reserved.               |
   | Released under BSD License. See: https://www.mrpt.org/License          |
   +------------------------------------------------------------------------+ */
#pragma once

#include <mrpt/config/CConfigFileBase.h>
#include <mrpt/math/TPoint2D.h>
#include <mrpt/nav/holonomic/ClearanceDiagram.h>
#include <mrpt/nav/tpspace/CParameterizedTrajectoryGenerator.h>
#include <mrpt/serialization/CSerializable.h>
#include <mrpt/typemeta/TEnumType.h>

#include "CHolonomicLogFileRecord.h"

namespace mrpt::nav
{
/** \addtogroup nav_holo Holonomic navigation methods
 * \ingroup mrpt_nav_grp
 * @{ */

/** A base class for holonomic reactive navigation methods.
 *  \sa CHolonomicVFF,CHolonomicND,CHolonomicFullEval, CReactiveNavigationSystem
 */
class CAbstractHolonomicReactiveMethod : public mrpt::serialization::CSerializable
{
  DEFINE_VIRTUAL_SERIALIZABLE(CAbstractHolonomicReactiveMethod, mrpt::nav)
 public:
  /** Input parameters for CAbstractHolonomicReactiveMethod::navigate() */
  struct NavInput
  {
    /** Distance to obstacles in polar coordinates, relative to the robot.
     * First index refers to -PI direction, and last one to +PI direction.
     * Distances can be dealed as "meters", although when used inside the
     * PTG-based navigation system, they are "pseudometers", normalized to
     * the range [0,1].
     */
    std::vector<double> obstacles;
    /** Relative location (x,y) of target point(s). In the same units than
     * `obstacles`. If many, last targets have higher priority. */
    std::vector<mrpt::math::TPoint2D> targets;
    /** Maximum robot speed, in the same units than `obstacles`, per second.
     */
    double maxRobotSpeed{1.0};
    /** Maximum expected value to be found in `obstacles`. Typically, values
     * in `obstacles` larger or equal to this value mean there is no visible
     * obstacle in that direction. */
    double maxObstacleDist{1.0};
    /** The computed clearance for each direction (optional in some
     * implementations). Leave to default (NULL) if not needed. */
    const mrpt::nav::ClearanceDiagram* clearance{nullptr};

    NavInput();
  };

  /** Output for CAbstractHolonomicReactiveMethod::navigate() */
  struct NavOutput
  {
    /** The desired motion direction, in the range [-PI, PI] */
    double desiredDirection{0};
    /** The desired motion speed in that direction, from 0 up to
     * NavInput::maxRobotSpeed */
    double desiredSpeed{0};

    /** The navigation method will create a log record and store it here via
     * a smart pointer. Input value is ignored. */
    CHolonomicLogFileRecord::Ptr logRecord;

    NavOutput();
  };

  static CAbstractHolonomicReactiveMethod::Ptr Factory(const std::string& className) noexcept;

  /** Invokes the holonomic navigation algorithm itself. See the description
   * of the input/output structures for details on each parameter. */
  virtual void navigate(const NavInput& ni, NavOutput& no) = 0;

  /** ctor */
  CAbstractHolonomicReactiveMethod(const std::string& defaultCfgSectionName);
  /** virtual dtor */
  ~CAbstractHolonomicReactiveMethod() override;

  /** Initialize the parameters of the navigator, reading from the default
   * section name (see derived classes) or the one set via
   * setConfigFileSectionName() */
  virtual void initialize(const mrpt::config::CConfigFileBase& c) = 0;
  /** saves all available parameters, in a forma loadable by `initialize()` */
  virtual void saveConfigFile(mrpt::config::CConfigFileBase& c) const = 0;
  /** Defines the name of the section used in initialize() */
  void setConfigFileSectionName(const std::string& sectName);
  /** Gets the name of the section used in initialize() */
  std::string getConfigFileSectionName() const;

  /** Returns the actual value of this parameter [m], as set via the children
   * class options structure. \sa setTargetApproachSlowDownDistance() */
  virtual double getTargetApproachSlowDownDistance() const = 0;
  /** Sets the actual value of this parameter [m]. \sa
   * getTargetApproachSlowDownDistance() */
  virtual void setTargetApproachSlowDownDistance(const double dist) = 0;

  /** Class factory from class name, e.g. `"CHolonomicVFF"`, etc.
   * \exception std::logic_error On invalid or missing parameters. */
  static CAbstractHolonomicReactiveMethod* Create(const std::string& className) noexcept;

  /** Optionally, sets the associated PTG, just in case a derived class
   * requires this info (not required for methods where the robot kinematics
   * are totally abstracted) */
  void setAssociatedPTG(mrpt::nav::CParameterizedTrajectoryGenerator* ptg);
  /** Returns the pointer set by setAssociatedPTG() */
  mrpt::nav::CParameterizedTrajectoryGenerator* getAssociatedPTG() const;

  void enableApproachTargetSlowDown(bool enable) { m_enableApproachTargetSlowDown = enable; }

 protected:
  /** If applicable, this will contain the argument of the most recent call to
   * setAssociatedPTG() */
  mrpt::nav::CParameterizedTrajectoryGenerator* m_associatedPTG;
  /** Whether to decrease speed when approaching target */
  bool m_enableApproachTargetSlowDown;

 private:
  /** used in setConfigFileSectionName(), initialize() */
  std::string m_cfgSectionName;
};
/** @} */
}  // namespace mrpt::nav
