/*!\file InterpFromMesh2d.c
 * \brief: data interpolation from a list of (x,y,values) into mesh vertices
 
	InterpFromMesh2d.c

	usage:
	data_mesh=InterpFromMesh2d(index,x,y,data,x_mesh,y_mesh);
	
	where:

		input:
		x,y: coordinates of matrix data
		data - matrix holding the data to be interpolated onto the mesh.
		x_mesh,y_mesh: coordinates of the mesh vertices onto which we interpolate.
		
		output: 
		data_mesh:  vector of mesh interpolated data.

*/
	
#include "./InterpFromMesh2d.h"

void mexFunction( int nlhs, mxArray* plhs[], int nrhs, const mxArray* prhs[]) {

	/*input: */
	double* index_data=NULL;
	int     index_data_rows;
	int     dummy;

	double* x_data=NULL;
	int     x_data_rows;
	
	double* y_data=NULL;
	int     y_data_rows;

	double* data=NULL; 
	int     data_rows;
	int     data_cols;

	double* x_prime=NULL;
	double* y_prime=NULL;
	
	int     x_prime_rows;
	int     y_prime_rows;


	double* default_values=NULL;
	int     num_default_values=0;

	//contours
	mxArray*  matlabstructure=NULL;
	Contour** contours=NULL;
	int       numcontours;
	Contour*  contouri=NULL;
	int       i;

	/*Intermediary*/
	int nods_data;
	int nels_data;
	int nods_prime;

	/* output: */
	Vec  data_prime=NULL;

	/*Boot module: */
	MODULEBOOT();

	/*checks on arguments on the matlab side: */
	if(nlhs!=NLHS){
		InterpFromMesh2dUsage();
		_error_("InterpFromMeshToMesh2dUsage usage error");
	}
	if((nrhs!=6) && (nrhs!=7) && (nrhs!=8)){
		InterpFromMesh2dUsage();
		_error_("InterpFromMeshToMesh2dUsage usage error");
	}

	/*Input datasets: */
	FetchMatlabData(&index_data,&index_data_rows,&dummy,INDEXHANDLE);
	FetchMatlabData(&x_data,&x_data_rows,NULL,XHANDLE);
	FetchMatlabData(&y_data,&y_data_rows,NULL,YHANDLE);
	FetchMatlabData(&data,&data_rows,&data_cols,DATAHANDLE);
	FetchMatlabData(&x_prime,&x_prime_rows,NULL,XPRIMEHANDLE);
	FetchMatlabData(&y_prime,&y_prime_rows,NULL,YPRIMEHANDLE);

	if(nrhs>=7){
		/*default values: */
		FetchMatlabData(&default_values,&num_default_values,DEFAULTHANDLE);
	}
	else{
		default_values=NULL;
		num_default_values=0;
	}

	if(nrhs>=8){
		
		/*Call expread on filename to build a contour array in the matlab workspace: */
		mexCallMATLAB( 1, &matlabstructure, 1, (mxArray**)&FILENAME, "expread");

		/*contours: */
		numcontours=mxGetNumberOfElements(matlabstructure);
		contours=(Contour**)xmalloc(numcontours*sizeof(Contour*));
		for(i=0;i<numcontours;i++){
			//allocate
			contouri=(Contour*)xmalloc(sizeof(Contour));
			//retrieve dimension of this contour.
			contouri->nods=(int)mxGetScalar(mxGetField(matlabstructure,i,"nods"));
			//set pointers.
			contouri->x=mxGetPr(mxGetField(matlabstructure,i,"x"));
			contouri->y=mxGetPr(mxGetField(matlabstructure,i,"y"));
			*(contours+i)=contouri;
		}

		/* Debugging of contours :{{{1*/
		/*for(i=0;i<numcontours;i++){
		  printf("\nContour echo: contour number  %i / %i\n",i+1,numcontours);
		  contouri=*(contours+i);
		  printf("   Number of vertices %i\n",contouri->nods);
		  for (j=0;j<contouri->nods;j++){
		  printf("   %lf %lf\n",*(contouri->x+j),*(contouri->y+j));
		  }
		  }*/
		/*}}}*/
	}
	else{
		numcontours=0;
		contours=NULL;
	}


	/*some checks*/
	if (x_data_rows!=y_data_rows){
		_error_("vectors x and y should have the same length!");
	}
	if (x_prime_rows!=y_prime_rows){
		_error_("vectors x_prime and y_prime should have the same length!");
	}
	
	/*get number of elements and number of nodes in the data*/
	nels_data=index_data_rows;
	nods_data=x_data_rows;
	nods_prime=x_prime_rows;

	/* Run core computations: */
	InterpFromMesh2dx(&data_prime,index_data,x_data,y_data,nods_data,nels_data,data,data_rows,x_prime,y_prime,nods_prime,default_values,num_default_values,contours,numcontours);

	/*Write data: */
	WriteMatlabData(DATAPRIME,data_prime);

	/*end module: */
	MODULEEND();
}

void InterpFromMesh2dUsage(void)
{
	_printf_(true,"   usage:\n");
	_printf_(true,"         data_prime=InterpFromMesh2d(index,x,y,data,x_prime,y_prime);\n\n");
	_printf_(true,"      or data_prime=InterpFromMesh2d(index,x,y,data,x_prime,y_prime,default_value);\n\n");
	_printf_(true,"      or data_prime=InterpFromMesh2d(index,x,y,data,x_prime,y_prime,default_value,contourname);\n\n");
	_printf_(true,"   where:\n");
	_printf_(true,"      x,y: coordinates of the nodes where data is defined\n");
	_printf_(true,"      index: index of the mesh where data is defined\n");
	_printf_(true,"      data - vector holding the data to be interpolated onto the points.\n");
	_printf_(true,"      x_prime,y_prime: coordinates of the mesh vertices onto which we interpolate.\n");
	_printf_(true,"      default_value: a scalar or vector of size length(x_prime).\n");
	_printf_(true,"      contourname: linear interpolation will happen on all x_interp,y_interp inside the contour, default value will be adopted on the rest of the mesh.\n");
	_printf_(true,"      data_prime:  vector of prime interpolated data.\n");
	_printf_(true,"\n");
}