/*ParseBackgrd parse options for the BACKGROUND command */
#include <string.h>
#include "cddefines.h"
#include "physconst.h"
#include "incidspec.h"
#include "radius.h"
#include "bounds.h"
#include "powi.h"
#include "ffmtread.h"
#include "lgmatch.h"
#include "parse.h"

void ParseBackgrd(long int *nqh, 
  char *chCard,
  float *ar1)
{
	int lgEOL;
	long int i;
	double a, 
	  fac, 
	  rlogl, 
	  z;

#	ifdef DEBUG_FUN
	fputs( "<+>ParseBackgrd()\n", debug_fp );
#	endif

	/* check that stack of shape and luminosity specifications
	 * is parallel, stop if not - this happens is background comes
	 * BETWEEN another set of shape and luminosity commands */
	if( IncidSpec.nspec != *nqh )
	{
		fprintf( ioQQQ, " This command has come between a previous ordered pair of continuum shape and luminosity commands.\n Reorder the commands to complete each continuum specification before starting another.\n" );
		fprintf( ioQQQ, " Sorry.\n" );
		puts( "[Stop in ParseBackgrd]" );
		exit(1);
	}

	/* diffuse x-ray background from Ostriker and Ikeuchi Ap.J.L 268, L63.
	 * parameter on card is redshift, followed by optional J21 (ApJ 301, 522) */
	IncidSpec.nspec += 1;
	if( IncidSpec.nspec > LIMSPC )
	{
		fprintf( ioQQQ, " Too many continua entered; increase LIMSPC\n" );
		puts( "[Stop in ParseBackgrd]" );
		exit(1);
	}

	strcpy( spnorm.chSpType[IncidSpec.nspec-1], "POWER" );
	IncidSpec.slope[IncidSpec.nspec-1] = -1.f;
	IncidSpec.cutoff[0][IncidSpec.nspec-1] = 1e10;
	IncidSpec.cutoff[1][IncidSpec.nspec-1] = 0.;

	/* now generate equivalent of luminosity command
	 * enter phi(h), the number of h-ionizing photons/cm2 */
	*nqh += 1;
	if( *nqh > LIMSPC )
	{
		fprintf( ioQQQ, " Too many continua entered; increase LIMSPC\n" );
		puts( "[Stop in ParseBackgrd]" );
		exit(1);
	}

	strcpy( spnorm.chRSpec[*nqh-1], "SQCM" );
	strcpy( spnorm.chSpNorm[*nqh-1], "FLUX" );
	i = 5;

	/* this will be the redshift */
	z = FFmtRead(chCard,&i,76,&lgEOL);
	if( lgEOL )
	{
		z = 0.;
	}

	/* optional scale factor */
	fac = FFmtRead(chCard,&i,76,&lgEOL);
	if( lgEOL )
	{
		fac = 1.0;
	}

	/* this equation from Ostriker and Ikeuchi Ap.J.L 268, L63.
	 * this should be J_nu into 4\pi sr
	 * >>chng 96 july 23, from ostriker to vedel, et al mnras 271, 743. */
	IncidSpec.totpow[*nqh-1] = (float)(log10(PI4*fac*1.e-21/
		(1.+powi(5./(1.+z),4))));

	/* this is at 1 ryd for H
	 * range(nqh,1) = 1.
	 *chnage 96 dec 18, to H ioniz pot from 1 ryd */
	IncidSpec.range[0][*nqh-1] = (float)HIONPOT;

	/* add fireball unless NO FIREBALL in */
	if( !lgMatch("O FI",chCard) )
	{
		IncidSpec.nspec += 1;
		*nqh += 1;
		if( *nqh > LIMSPC )
		{
			fprintf( ioQQQ, " Too many continua entered; increase LIMSPC\n" );
			puts( "[Stop in ParseBackgrd]" );
			exit(1);
		}

		/* put in a black body */
		strcpy( spnorm.chSpType[IncidSpec.nspec-1], "BLACK" );
		IncidSpec.slope[IncidSpec.nspec-1] = (float)(2.756*(1. + z));
		IncidSpec.cutoff[0][IncidSpec.nspec-1] = 0.;
		IncidSpec.cutoff[1][IncidSpec.nspec-1] = 0.;
		strcpy( spnorm.chSpNorm[*nqh-1], "LUMI" );
		a = log10(IncidSpec.slope[IncidSpec.nspec-1]);
		rlogl = log10(2.99792e10*7.56464e-15) + 4.*a;
		strcpy( spnorm.chRSpec[*nqh-1], "SQCM" );
		IncidSpec.range[0][*nqh-1] = bounds.emm;
		IncidSpec.range[1][*nqh-1] = bounds.egamry;
		IncidSpec.totpow[*nqh-1] = (float)rlogl;
	}

	/* set radius to very large value if not already set */
	if( radius.Radius == 0. )
	{
		*ar1 = (float)radius.rdfalt;
		radius.Radius = pow(10.,*ar1);
	}

#	ifdef DEBUG_FUN
	fputs( " <->ParseBackgrd()\n", debug_fp );
#	endif
	return;
}