/* Distributed under the Apache License, Version 2.0.
   See accompanying NOTICE file for details.*/

#pragma once
#include "PulsePhysiologySystems.h"
#include "system/physiology/SEGastrointestinalSystem.h"
class SELiquidCompartment;
class SELiquidSubstanceQuantity;
class SEFluidCircuitPath;

/**
* @brief @copydoc Physiology_GastrointestinalSystemData
*/
class PULSE_DECL Gastrointestinal : public PulseGastrointestinalSystem
{
  friend class PulseController;
  friend class PBPulsePhysiology;//friend the serialization class
  friend class PulseEngineTest;
public:
  Gastrointestinal(PulseData& data);
  virtual ~Gastrointestinal();

  void Clear();

  // Set members to a stable homeostatic state
  void Initialize();
  // Set pointers and other member varialbes common to both homeostatic initialization and loading a state
  void SetUp();

  void AtSteadyState();
  void PreProcess();
  void Process(bool solve_and_transport = true);
  void PostProcess(bool solve_and_transport = true);

protected:
  void ComputeExposedModelParameters() override;

  void   DefaultNutritionRates(SENutrition& n);
  void   DigestStomachNutrients(double duration_s);
  double DigestNutrient(SEUnitScalar& totalAmt, SEUnitScalar& rate, bool mass, double duration_s);

  // Serializable member variables (Set in Initialize and in schema)  

  // Stateless member variable (Set in SetUp())
  SEFluidCircuitPath* m_GItoCVPath;
  SEScalarMassPerTime* m_CalciumDigestionRate;
  SEScalarVolumePerTime* m_WaterDigestionRate;

  SELiquidCompartment*       m_SmallIntestine;
  SELiquidSubstanceQuantity* m_SmallIntestineGlucose;
  SELiquidSubstanceQuantity* m_SmallIntestineTristearin;
  SELiquidSubstanceQuantity* m_SmallIntestineCalcium;
  SELiquidSubstanceQuantity* m_SmallIntestineSodium;
  SELiquidSubstanceQuantity* m_SmallIntestineUrea;
  SELiquidCompartment*       m_SmallIntestineChyme;

  bool   m_ConsumeRate; // Some substance digestion rates are specified by the user, some by configuration,
  //if the stomach runs out of a substance with a user provided rate, we invalidate the rate (true)
  //if the rate is a configuration rate, we don't want to invalidate it if we run out of the substance (false)
  double m_dT_s;

};
