#pragma once

#include "Common.h"
#include "ParameterObject.h"
#include "FluidModel.h"
#include "BoundaryModel.h"
#include "Discregrid/discrete_grid.hpp"

namespace SPH
{
	/** \brief Base class for the simulation methods. 
	*/
	class TimeStep : public GenParam::ParameterObject
	{
	protected:
		/** Clear accelerations and add gravitation.
		*/
		void clearAccelerations(const unsigned int fluidModelIndex);

		virtual void initParameters();

		void approximateNormal(Discregrid::DiscreteGrid* map, const Eigen::Vector3d &x, Eigen::Vector3d &n, const unsigned int dim);
		void computeVolumeAndBoundaryX(const unsigned int fluidModelIndex, const unsigned int i, const Vector3r &xi);
		void computeVolumeAndBoundaryX();
		void computeDensityAndGradient(const unsigned int fluidModelIndex, const unsigned int i, const Vector3r &xi);
		void computeDensityAndGradient();

	public:
		TimeStep();
		virtual ~TimeStep(void);

		/** Determine densities of all fluid particles.
		*/
		void computeDensities(const unsigned int fluidModelIndex);

		/** returns the name of the method */
		virtual std::string getMethodName() = 0;
		virtual void step() = 0;
		virtual void reset();

		virtual void init();
		virtual void resize() = 0;

		virtual void emittedParticles(FluidModel *model, const unsigned int startIndex) {};

		/** Important: First call m_model->performNeighborhoodSearchSort()
			 * to call the z_sort of the neighborhood search.
			 */
		virtual void performNeighborhoodSearchSort() {};

		virtual void saveState(BinaryFileWriter &binWriter) {};
		virtual void loadState(BinaryFileReader &binReader) {};

		virtual int getNumIterations() = 0;

#ifdef USE_PERFORMANCE_OPTIMIZATION
		void precomputeValues();
#endif
	};
}