# include <hstio.h>
# include "../acs.h"
# include "../acsinfo.h"


/* The science data and the error array values are multiplied by k;
   the data quality array is not modified.
*/

int multk1d (SingleGroupLine *a, float k) {

/* arguments:
SingleGroupLine *a   io: input data; output product
float k          	  i: multiply a by this constant
*/

	int i;
    int dimx;

	if (k == 1.)
	    return (0);
       
    /* science data */
	/* error array */
    dimx = a->sci.tot_nx;

    for (i = 0;  i < dimx;  i++) {
		a->sci.line[i] = k * a->sci.line[i];
		a->err.line[i] = k * a->err.line[i];
    }
    
	return (0);
}

int multkline (float *a, float k, int dimx) {

/* arguments:
float   *a              io: input data; output product
float   k            	 i: multiply a by this constant
int     dimx             i: size of array
*/
	int i;

	if (k == 1.)
	    return (0);

    for (i = 0;  i < dimx;  i++)
		a[i] = k * a[i];

	return (0);
}

/* This routine computes the average of the science data values
** from a single line of the image
** that are not flagged as bad by the data quality array.
*/

void AvgSciValLine (SingleGroupLine *y, short sdqflags,
		float *mean, float *weight) {

	double sum;
	int numgood;			/* number of good pixels */
	int i;
	short flagval;			/* data quality flag value */
    int dimx;

	numgood = 0;
	sum = 0.;
    dimx = y->sci.tot_nx;
    
	for (i = 0;  i < dimx;  i++) {
		flagval = y->dq.line[i];
		if ( ! (sdqflags & flagval) ) {
		    /* no serious flag bit set */
		    sum += y->sci.line[i];
		    numgood++;
		}
	}

	if (numgood > 0) {
	    *mean = sum / (double) numgood;
        *weight = (float) numgood / (float)y->sci.tot_nx;
	} else { 
	    *mean = 0.;
        *weight = 0.;
    }
}

void multgn1d (SingleGroupLine *a, int line, ACSInfo *acs, float *gain) {

/* arguments:
SingleGroupLine *a   io: input data; output product
int line			  i: line number of input line
AcsInfo *acs		  i: exptime and atodgain parameters
float *gain
*/
	int i;
	float k0,k;
    int dimx;

	/* Determine k */
	k0 = acs->exptime;
    k = 0;
    dimx = a->sci.tot_nx;
    
    /* Since both the science and error arrays operate on the 
        same line of data, we will combine them into one loop over
        X values.
    */
	/* science data and error array */
	if (line < acs->ampy ) {
        if (gain[AMP_C] > 0.) {
            k = k0 / gain[AMP_C];
        } else {
            k = 0.;
        } 
        /* This line has 2-AMP readout */
        /* Apply gain for first amp to first part of line */
        for (i = 0;  i < acs->ampx;  i++) {
			a->sci.line[i] = k * a->sci.line[i];
			a->err.line[i] = k * a->err.line[i];        
        }
        /* Apply gain for second amp over remainder of line...
            only if there is a second amp which needs applying.
            WJH 14 Apr 2000
        */
        if (acs->ampx < dimx) {
            k = k0 / gain[AMP_D];
            for (i = acs->ampx;  i < dimx;  i++) {
			    a->sci.line[i] = k * a->sci.line[i];
			    a->err.line[i] = k * a->err.line[i];        
            }
        }

    } else {
        if (gain[AMP_A] > 0.) {
            k = k0 / gain[AMP_A];
        } else {
            k = 0.;
        }
        /* This line has 2-AMP readout */
        /* Apply gain for first amp to first part of line */
        for (i = 0;  i < acs->ampx;  i++) {
			a->sci.line[i] = k * a->sci.line[i];
			a->err.line[i] = k * a->err.line[i];        
        }
        /* Apply gain for second amp over remainder of line... 
            only if there is a second amp which needs applying.
            WJH 14 Apr 2000
        */
        if (acs->ampx < dimx) {
            k = k0 / gain[AMP_B];
            for (i = acs->ampx;  i < dimx;  i++) {
			    a->sci.line[i] = k * a->sci.line[i];
			    a->err.line[i] = k * a->err.line[i];        
            }
        }
    }
}