/**
 * File: behaviorInteractWithFaces.h
 *
 * Author: Brad Neuman
 * Created: 2016-08-22
 *
 * Description: Turn towards a face and "interact" with it, which for now just means drive towards it and
 *              track it for a while.
 *
 * NOTE: This behavior shares a name with an older "interact with faces" behavior, but has been re-written
 * since then
 *
 * Copyright: Anki, Inc. 2016
 *
 **/

#ifndef __Cozmo_Basestation_Behaviors_BehaviorInteractWithFaces_H__
#define __Cozmo_Basestation_Behaviors_BehaviorInteractWithFaces_H__

#include "engine/aiComponent/behaviorComponent/behaviors/iCozmoBehavior.h"
#include "util/cladHelpers/cladFromJSONHelpers.h"
#include "engine/smartFaceId.h"
#include "coretech/common/engine/robotTimeStamp.h"
#include "coretech/vision/engine/faceIdTypes.h"

#include <string>
#include <unordered_map>

namespace Anki {

namespace Vision {
class TrackedFace;
}

namespace Vector {

namespace ExternalInterface {
struct RobotObservedFace;
struct RobotDeletedFace;
struct RobotChangedObservedFaceID;
}

class BehaviorInteractWithFaces : public ICozmoBehavior
{
protected:
    
  // Enforce creation through BehaviorFactory
  friend class BehaviorFactory;
  BehaviorInteractWithFaces(const Json::Value& config);
    
public:

  virtual bool WantsToBeActivatedBehavior() const override;
    
protected:

  // - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
  // ICozmoBehavior API
  // - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
  virtual void GetBehaviorOperationModifiers(BehaviorOperationModifiers& modifiers) const override;
  virtual void GetBehaviorJsonKeys(std::set<const char*>& expectedKeys) const override;

  virtual void OnBehaviorActivated() override;
  virtual void BehaviorUpdate() override;
  virtual void OnBehaviorDeactivated() override;

  // - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
  // ICozmoBehavior API
  // - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -

private:
  using BaseClass = ICozmoBehavior;
  using Face = Vision::TrackedFace;

  struct InstanceConfig {
    InstanceConfig();
    float minTimeToTrackFaceLowerBound_s;
    float minTimeToTrackFaceUpperBound_s;

    float maxTimeToTrackFaceLowerBound_s;
    float maxTimeToTrackFaceUpperBound_s;

    float noEyeContactTimeout_s;
    float trackingTimeout_s;
    TimeStamp_t eyeContactWithinLast_ms;

    float minTrackingTiltAngle_deg;
    float minTrackingPanAngle_deg;

    float minClampPeriod_s;
    float maxClampPeriod_s;
    bool clampSmallAngles;
  };

  struct DynamicVariables {
    DynamicVariables();
    // ID of face we are currently interested in
    mutable SmartFaceID targetFace;
    // We only want to run for faces we've seen since the last time we ran, so keep track of the final timestamp
    // when the behavior finishes
    RobotTimeStamp_t lastImageTimestampWhileRunning;
    // In the face tracking stage the action will hang, so store a time at which we want to stop it (from within
    // Update)
    float trackFaceUntilTime_s;
  };

  InstanceConfig   _iConfig;
  DynamicVariables _dVars;

  void LoadConfig(const Json::Value& config);

  // sets the mutbale _dVars.targetFace to the face we want to interact with
  void SelectFaceToTrack() const;

  void TransitionToInitialReaction();
  void TransitionToGlancingDown();
  void TransitionToDrivingForward();
  void TransitionToTrackingFace();
  void TransitionToTriggerEmotionEvent();

  bool CanDriveIdealDistanceForward();
    
}; // BehaviorInteractWithFaces
  
} // namespace Vector
} // namespace Anki

#endif // __Cozmo_Basestation_Behaviors_BehaviorInteractWithFaces_H__