/*
 * 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 _GAZEBO_WORLD_HH_
#define _GAZEBO_WORLD_HH_

#ifdef _WIN32
// Ensure that Winsock2.h is included before Windows.h, which can get
// pulled in by anybody (e.g., Boost).
#include <Winsock2.h>
#endif

#include <vector>
#include <list>
#include <set>
#include <deque>
#include <string>
#include <boost/thread.hpp>
#include <boost/enable_shared_from_this.hpp>
#include <boost/shared_ptr.hpp>

#include <sdf/sdf.hh>

#include "gazebo/transport/TransportTypes.hh"

#include "gazebo/msgs/msgs.hh"

#include "gazebo/common/CommonTypes.hh"
#include "gazebo/common/UpdateInfo.hh"
#include "gazebo/common/Event.hh"

#include "gazebo/physics/Base.hh"
#include "gazebo/physics/PhysicsTypes.hh"
#include "gazebo/physics/WorldState.hh"
#include "gazebo/util/system.hh"

// Added by zhangshuai based on zenglei 2019.03.19 ----Begin
/// add for Tcp communication
#include "gazebo/physics/TcpCommunication.hh"
// Added by zhangshuai based on zenglei 2019.03.19 ----End

// Added by zhangshuai 2019.04.01 ----Begin
#include "gazebo/physics/Distribution.hh"
// Added by zhangshuai 2019.04.01 ----End

namespace gazebo
{
namespace physics
{
/// Forward declare private data class.
class WorldPrivate;

// struct CommunicationData;
// class TcpServer;
// class TcpClient;

/// \addtogroup gazebo_physics
/// \{

/// \class World World.hh physics/physics.hh
/// \brief The world provides access to all other object within a simulated
/// environment.
///
/// The World is the container for all models and their components
/// (links, joints, sensors, plugins, etc), and WorldPlugin instances.
/// Many core function are also handled in the World, including physics
/// update, model updates, and message processing.
class GZ_PHYSICS_VISIBLE World : public boost::enable_shared_from_this<World>
{
  /// \brief Constructor.
  /// Constructor for the World. Must specify a unique name.
  /// \param[in] _name Name of the world.
public:
  explicit World(const std::string &_name = "");

  /// \brief Destructor.
public:
  ~World();

  /// \brief Load the world using SDF parameters.
  /// Load a world from and SDF pointer.
  /// \param[in] _sdf SDF parameters.
public:
  void Load(sdf::ElementPtr _sdf);

  /// \brief Save a world to a file.
  /// Save the current world and its state to a file.
  /// \param[in] _filename Name of the file to save into.
public:
  void Save(const std::string &_filename);

  /// \brief Initialize the world.
  /// This is called after Load.
public:
  void Init();

  /// \brief Run the world in a thread.
  /// Run the update loop.
  /// \param[in] _iterations Run for this many iterations, then stop.
  /// A value of zero disables run stop.
public:
  void Run(unsigned int _iterations = 0);

  /// \brief Return the running state of the world.
  /// \return True if the world is running.
public:
  bool GetRunning() const;

  /// \brief Stop the world.
  /// Stop the update loop.
public:
  void Stop();

  /// \brief Finalize the world.
  /// Call this function to tear-down the world.
public:
  void Fini();

  /// \brief Remove all entities from the world.
  /// This function has delayed effect. Models are cleared at the end
  /// of the current update iteration.
public:
  void Clear();

  /// \brief Get the name of the world.
  /// \return The name of the world.
public:
  std::string GetName() const;

  /// \brief Return the physics engine.
  /// Get a pointer to the physics engine used by the world.
  /// \return Pointer to the physics engine.
public:
  PhysicsEnginePtr GetPhysicsEngine() const;

  /// \brief Return the preset manager.
  /// \return Pointer to the preset manager.
public:
  PresetManagerPtr GetPresetManager() const;

  /// \brief Return the spherical coordinates converter.
  /// \return Pointer to the spherical coordinates converter.
public:
  common::SphericalCoordinatesPtr GetSphericalCoordinates() const;

  /// \brief Return the gravity vector.
  /// \return The gravity vector.
public:
  ignition::math::Vector3d Gravity() const;

  /// \brief Set the gravity vector.
  /// \param[in] _gravity New gravity vector.
public:
  void SetGravity(const ignition::math::Vector3d &_gravity);

  /// \brief Set the gravity sdf value.
  /// \param[in] _gravity New gravity vector.
public:
  void SetGravitySDF(const ignition::math::Vector3d &_gravity);

  /// \brief Return the magnetic field vector.
  /// \return The magnetic field vector.
public:
  virtual ignition::math::Vector3d MagneticField() const;

  /// \brief Set the magnetic field vector.
  /// \param[in] _mag New magnetic field vector.
public:
  void SetMagneticField(const ignition::math::Vector3d &_mag);

  /// \brief Get the number of models.
  /// \return The number of models in the World.
public:
  unsigned int GetModelCount() const;

  /// \brief Get a model based on an index.
  /// Get a Model using an index, where index must be greater than zero
  /// and less than World::GetModelCount()
  /// \param[in] _index The index of the model [0..GetModelCount)
  /// \return A pointer to the Model. NULL if _index is invalid.
public:
  ModelPtr GetModel(unsigned int _index) const;

  /// \brief Get a list of all the models.
  /// \return A list of all the Models in the world.
public:
  Model_V GetModels() const;

  /// \brief Get the number of lights.
  /// \return The number of lights in the World.
public:
  unsigned int LightCount() const;

  /// \brief Get a list of all the lights.
  /// \return A list of all the Lights in the world.
public:
  Light_V Lights() const;

  /// \brief Reset with options.
  /// The _type parameter specifies which type of eneities to reset. See
  /// Base::EntityType.
  /// \param[in] _type The type of reset.
public:
  void ResetEntities(Base::EntityType _type = Base::BASE);

  /// \brief Reset simulation time back to zero.
public:
  void ResetTime();

  /// \brief Reset time and model poses, configurations in simulation.
public:
  void Reset();

  /// \brief Print Entity tree.
  /// Prints alls the entities to stdout.
public:
  void PrintEntityTree();

  /// \brief Get the world simulation time, note if you want the PC
  /// wall clock call common::Time::GetWallTime.
  /// \return The current simulation time
public:
  common::Time GetSimTime() const;

  /// \brief Set the sim time.
  /// \param[in] _t The new simulation time
public:
  void SetSimTime(const common::Time &_t);

  /// \brief Get the amount of time simulation has been paused.
  /// \return The pause time.
public:
  common::Time GetPauseTime() const;

  /// \brief Get the wall time simulation was started..
  /// \return The start time.
public:
  common::Time GetStartTime() const;

  /// \brief Get the real time (elapsed time).
  /// \return The real time.
public:
  common::Time GetRealTime() const;

  /// \brief Returns the state of the simulation true if paused.
  /// \return True if paused.
public:
  bool IsPaused() const;

  /// \brief Set whether the simulation is paused.
  /// \param[in] _p True pauses the simulation. False runs the simulation.
public:
  void SetPaused(bool _p);

  /// \brief Get an element by name.
  /// Searches the list of entities, and return a pointer to the model
  /// with a matching _name.
  /// \param[in] _name The name of the Model to find.
  /// \return A pointer to the entity, or NULL if no entity was found.
public:
  BasePtr GetByName(const std::string &_name);

  /// \brief Get a model by name.
  /// This function is the same as GetByName, but limits the search to
  /// only models.
  /// \param[in] _name The name of the Model to find.
  /// \return A pointer to the Model, or NULL if no model was found.
public:
  ModelPtr GetModel(const std::string &_name);

  /// \brief Get a light by name.
  /// This function is the same as GetByName, but limits the search to
  /// only lights.
  /// \param[in] _name The name of the Light to find.
  /// \return A pointer to the Light, or NULL if no light was found.
public:
  LightPtr Light(const std::string &_name);

  /// \brief Get a pointer to an Entity based on a name.
  /// This function is the same as GetByName, but limits the search to
  /// only Entities.
  /// \param[in] _name The name of the Entity to find.
  /// \return A pointer to the Entity, or NULL if no Entity was found.
public:
  EntityPtr GetEntity(const std::string &_name);

  /// \brief Get the nearest model below and not encapsulating a point.
  /// Only objects below the start point can be returned. Any object
  /// that encapsulates the start point can not be returned from this
  /// function.
  /// This function makes use of World::GetEntityBelowPoint.
  /// \param[in] _pt The 3D point to search below.
  /// \return A pointer to nearest Model, NULL if none is found.
public:
  ModelPtr GetModelBelowPoint(const math::Vector3 &_pt);

  /// \brief Get the nearest entity below a point.
  /// Projects a Ray down (-Z axis) starting at the given point. The
  /// first entity hit by the Ray is returned.
  /// \param[in] _pt The 3D point to search below
  /// \return A pointer to nearest Entity, NULL if none is found.
public:
  EntityPtr GetEntityBelowPoint(const math::Vector3 &_pt);

  /// \brief Set the current world state.
  /// \param _state The state to set the World to.
public:
  void SetState(const WorldState &_state);

  /// \brief Insert a model from an SDF file.
  /// Spawns a model into the world base on and SDF file.
  /// \param[in] _sdfFilename The name of the SDF file (including path).
public:
  void InsertModelFile(const std::string &_sdfFilename);

  /// \brief Insert a model from an SDF string.
  /// Spawns a model into the world base on and SDF string.
  /// \param[in] _sdfString A string containing valid SDF markup.
public:
  void InsertModelString(const std::string &_sdfString);

  /// \brief Insert a model using SDF.
  /// Spawns a model into the world base on and SDF object.
  /// \param[in] _sdf A reference to an SDF object.
public:
  void InsertModelSDF(const sdf::SDF &_sdf);

  /// \brief Return a version of the name with "<world_name>::" removed
  /// \param[in] _name Usually the name of an entity.
  /// \return The stripped world name.
public:
  std::string StripWorldName(const std::string &_name) const;

  /// \brief Enable all links in all the models.
  /// Enable is a physics concept. Enabling means that the physics
  /// engine should update an entity.
public:
  void EnableAllModels();

  /// \brief Disable all links in all the models.
  /// Disable is a physics concept. Disabling means that the physics
  /// engine should not update an entity.
public:
  void DisableAllModels();

  /// \brief Step the world forward in time.
  /// \param[in] _steps The number of steps the World should take.
public:
  void Step(unsigned int _steps);

  /// \brief Load a plugin
  /// \param[in] _filename The filename of the plugin.
  /// \param[in] _name A unique name for the plugin.
  /// \param[in] _sdf The SDF to pass into the plugin.
public:
  void LoadPlugin(const std::string &_filename,
                  const std::string &_name,
                  sdf::ElementPtr _sdf);

  /// \brief Remove a running plugin.
  /// \param[in] _name The unique name of the plugin to remove.
public:
  void RemovePlugin(const std::string &_name);

  /// \brief Get the set world pose mutex.
  /// \return Pointer to the mutex.
public:
  boost::mutex *GetSetWorldPoseMutex() const;

  /// \brief check if physics engine is enabled/disabled.
  /// \param True if the physics engine is enabled.
public:
  bool GetEnablePhysicsEngine();

  /// \brief enable/disable physics engine during World::Update.
  /// \param[in] _enable True to enable the physics engine.
public:
  void EnablePhysicsEngine(bool _enable);

  /// \brief Update the state SDF value from the current state.
public:
  void UpdateStateSDF();

  /// \brief Return true if the world has been loaded.
  /// \return True if World::Load has completed.
public:
  bool IsLoaded() const;

  /// \brief Remove all entities from the world. Implementation of
  /// World::Clear
public:
  void ClearModels();

  /// \brief Publish pose updates for a model.
  /// This list of models to publish is processed and cleared once every
  /// iteration.
  /// \param[in] _model Pointer to the model to publish.
public:
  void PublishModelPose(physics::ModelPtr _model);

  /// \brief Publish scale updates for a model.
  /// This list of models to publish is processed and cleared once every
  /// iteration.
  /// \param[in] _model Pointer to the model to publish.
public:
  void PublishModelScale(physics::ModelPtr _model);

  /// \brief Publish pose updates for a light.
  /// Adds light to a list of lights to publish, which is processed and
  /// cleared once every iteration.
  /// \param[in] _light Pointer to the light to publish.
public:
  void PublishLightPose(const physics::LightPtr _light);

  /// \brief Get the total number of iterations.
  /// \return Number of iterations that simulation has taken.
public:
  uint32_t GetIterations() const;

  /// \brief Get the current scene in message form.
  /// \return The scene state as a protobuf message.
public:
  msgs::Scene GetSceneMsg() const;

  /// \brief Run the world. This call blocks.
  /// Run the update loop.
  /// \param[in] _iterations Run for this many iterations, then stop.
  /// A value of zero disables run stop.
public:
  void RunBlocking(unsigned int _iterations = 0);

  /// \brief Remove a model. This function will block until
  /// the physics engine is not locked. The duration of the block
  /// is less than the time to complete a simulation iteration.
  /// \param[in] _model Pointer to a model to remove.
public:
  void RemoveModel(ModelPtr _model);

  /// \brief Remove a model by name. This function will block until
  /// the physics engine is not locked. The duration of the block
  /// is less than the time to complete a simulation iteration.
  /// \param[in] _name Name of the model to remove.
public:
  void RemoveModel(const std::string &_name);

  /// \brief Reset the velocity, acceleration, force and torque of
  /// all child models.
public:
  void ResetPhysicsStates();

  /// \internal
  /// \brief Inform the World that an Entity has moved. The Entity
  /// is added to a list that will be processed by the World.
  /// Only a physics engine implementation should call this function.
  /// If you are unsure whether you should use this function, do not.
  /// \param[in] _entity Entity that has moved.
public:
  void _AddDirty(Entity *_entity);

  /// \brief Get whether sensors have been initialized.
  /// \return True if sensors have been initialized.
public:
  bool SensorsInitialized() const;

  /// \internal
  /// \brief Set whether sensors have been initialized. This should only
  /// be called by SensorManager.
  /// \param[in] _init True if sensors have been initialized.
public:
  void _SetSensorsInitialized(const bool _init);

  /// \brief Get a model name which doesn't overlap with any existing
  /// models, by appending numbers to the given name. If _name is already,
  /// unique, the returned value is the same.
  /// \param[in] _name Desired model name.
  /// \return Unique model name.
public:
  std::string UniqueModelName(const std::string &_name);

  /// \cond
  /// This is an internal function.
  /// \brief Get a model by id.
  /// Each Entity has a unique ID, this function finds a Model with
  /// a passed in _id.
  /// \param[in] _id The id of the Model
  /// \return A pointer to the model, or NULL if no Model was found.
private:
  ModelPtr GetModelById(unsigned int _id);
  /// \endcond

  /// \brief Load all plugins.
  ///
  /// Load all plugins specified in the SDF for the model.
private:
  void LoadPlugins();

  /// \brief Create and load all entities.
  /// \param[in] _sdf SDF element.
  /// \param[in] _parent Parent of the model to load.
private:
  void LoadEntities(sdf::ElementPtr _sdf, BasePtr _parent);

  /// \brief Load a model.
  /// \param[in] _sdf SDF element containing the Model description.
  /// \param[in] _parent Parent of the model.
  /// \return Pointer to the newly created Model.
private:
  ModelPtr LoadModel(sdf::ElementPtr _sdf, BasePtr _parent);

  /// \brief Load a light.
  /// \param[in] _sdf SDF element containing the Light description.
  /// \param[in] _parent Parent of the light.
  /// \return Pointer to the newly created Light.
public:
  LightPtr LoadLight(const sdf::ElementPtr &_sdf,
                     const BasePtr &_parent);

  /// \brief Load an actor.
  /// \param[in] _sdf SDF element containing the Actor description.
  /// \param[in] _parent Parent of the Actor.
  /// \return Pointer to the newly created Actor.
private:
  ActorPtr LoadActor(sdf::ElementPtr _sdf, BasePtr _parent);

  /// \brief Load a road.
  /// \param[in] _sdf SDF element containing the Road description.
  /// \param[in] _parent Parent of the Road.
  /// \return Pointer to the newly created Road.
private:
  RoadPtr LoadRoad(sdf::ElementPtr _sdf, BasePtr _parent);

  /// \brief Function to run physics. Used by physicsThread.
private:
  void RunLoop();

  /// \brief Step the world once.
private:
  void Step();

  /// \brief Step the world once by reading from a log file.
private:
  void LogStep();

  /// \brief Update the world.
private:
  void Update();

  /// \brief Pause callback.
  /// \param[in] _p True if paused.
private:
  void OnPause(bool _p);

  /// \brief Step callback.
private:
  void OnStep();

  /// \brief Called when a world control message is received.
  /// \param[in] _data The world control message.
private:
  void OnControl(ConstWorldControlPtr &_data);

  /// \brief Called when log playback control message is received.
  /// \param[in] _data The log playback control message.
private:
  void OnPlaybackControl(ConstLogPlaybackControlPtr &_data);

  /// \brief Called when a request message is received.
  /// \param[in] _msg The request message.
private:
  void OnRequest(ConstRequestPtr &_msg);

  /// \brief Construct a scene message from the known world state
  /// \param[out] _scene Scene message to build.
  /// \param[in] _entity Pointer to entity from which to build the scene
  /// message.
private:
  void BuildSceneMsg(msgs::Scene &_scene, BasePtr _entity);

  /// \brief Logs joint information.
  /// \param[in] _msg Incoming joint message.
private:
  void JointLog(ConstJointPtr &_msg);

  /// \brief Called when a factory message is received.
  /// \param[in] _data The factory message.
private:
  void OnFactoryMsg(ConstFactoryPtr &_data);

  /// \brief Called when a model message is received.
  /// \param[in] _msg The model message.
private:
  void OnModelMsg(ConstModelPtr &_msg);

  /// \brief TBB version of model updating.
private:
  void ModelUpdateTBB();

  /// \brief Single loop version of model updating.
private:
  void ModelUpdateSingleLoop();

  /// \brief Helper function to load a plugin from SDF.
  /// \param[in] _sdf SDF plugin description.
private:
  void LoadPlugin(sdf::ElementPtr _sdf);

  /// \brief Fills a model message with data from a model
  /// \param[out] _msg Model message to fill.
  /// \param[in] _model Pointer to the model to get the data from.
private:
  void FillModelMsg(msgs::Model &_msg, ModelPtr _model);

  /// \brief Process all received entity messages.
  /// Must only be called from the World::ProcessMessages function.
private:
  void ProcessEntityMsgs();

  /// \brief Process all received request messages.
  /// Must only be called from the World::ProcessMessages function.
private:
  void ProcessRequestMsgs();

  /// \brief Process all received factory messages.
  /// Must only be called from the World::ProcessMessages function.
private:
  void ProcessFactoryMsgs();

  /// \brief Process all received model messages.
  /// Must only be called from the World::ProcessMessages function.
private:
  void ProcessModelMsgs();

  /// \brief Process all received light factory messages.
  /// Must only be called from the World::ProcessMessages function.
private:
  void ProcessLightFactoryMsgs();

  /// \brief Process all received light modify messages.
  /// Must only be called from the World::ProcessMessages function.
private:
  void ProcessLightModifyMsgs();

  /// \brief Process all received log playback control messages.
  /// Must only be called from the World::ProcessMessages function.
private:
  void ProcessPlaybackControlMsgs();

  /// \brief Log callback. This is where we write out state info.
private:
  bool OnLog(std::ostringstream &_stream);

  /// \brief Save model resources while recording a log, such as meshes
  /// and textures.
private:
  void LogModelResources();

  /// \brief Process all incoming messages.
private:
  void ProcessMessages();

  /// \brief Publish the world stats message.
private:
  void PublishWorldStats();

  /// \brief Thread function for logging state data.
private:
  void LogWorker();

  /// \brief Callback when a light message is received.
  /// \param[in] _msg Pointer to the light message.
  /// \deprecated Topic ~/light deprecated.
  /// See OnLightFactoryMsg which subscribes to ~/factory/light and
  /// OnLightModifyMsg which subscribes to ~/light/modify
private:
  void OnLightMsg(ConstLightPtr &_msg);

  /// \brief Callback when a light message is received in the
  /// ~/factory/light topic.
  /// \param[in] _msg Pointer to the light message.
private:
  void OnLightFactoryMsg(ConstLightPtr &_msg);

  /// \brief Callback when a light message is received in the
  /// ~/light/modify topic.
  /// \param[in] _msg Pointer to the light message.
private:
  void OnLightModifyMsg(ConstLightPtr &_msg);

  /// \internal
  /// \brief Private data pointer.
private:
  WorldPrivate *dataPtr;

  /// Friend DARTLink so that it has access to dataPtr->dirtyPoses
private:
  friend class DARTLink;

  /// Friend SimbodyPhysics so that it has access to dataPtr->dirtyPoses
private:
  friend class SimbodyPhysics;

  // Added by zhangshuai based on zenglei 2019.03.19 ----Begin
  /// add for Tcp communication
private:
  TcpClient gazeboOne;

private:
  TcpServer gazeboZero;

  // private:
  //   std::string ip;

  // private:
  //   int type_; //0:server:gazeboZero; 1:client:gazeboOne;

private:
  int port;

private:
  int flag;

  // private:
  //   unsigned int simula_entity_num;

  // private:
  //   unsigned int shadow_entity_num;

private:
  CommunicationData infor[50];
  // Added by zhangshuai based on zenglei 2019.03.19 ----End

  // Added by zhangshuai 2019.04.01 ----Begin
  /// \brief the .
private:
  unsigned int gazeboLocalID;

  /// \brief the .
private:
  // Distribution_V distributions;
  DistributionPtr distribution;

public:
  DistributionPtr GetDistribution();

public:
  unsigned int GetGazeboLocalID();

public:
  unsigned int GetFlag();
  // Added by zhangshuai 2019.04.01 ----End
};
/// \}
} // namespace physics
} // namespace gazebo
#endif