#include "stdio.h"
#include "stdlib.h"
#include "math.h"
#include "string.h"

/*
	Convert sphere model from PyMol to WRL
	And create a geom as well.
	Not a general converter, highly specialised to this limited variety of PovRay file
*/

#define MIN(x,y) (x < y ? x : y)
#define MAX(x,y) (x > y ? x : y)
#define TRUE  1
#define FALSE 0

typedef struct {
	double x,y,z;
} XYZ;
typedef struct {
   double r,g,b;
} COLOUR;
typedef struct {
	XYZ p;
	double r;
	COLOUR c;
} SPHERE;

void WRLHeader(FILE *,char *,double);
void WRLSphere(FILE *,XYZ,double,COLOUR);
int ReadUntil(FILE *,int,char *);

int main(int argc,char **argv)
{
	int i;
	SPHERE *spheres = NULL;
	int nspheres = 0;
	double scale = 1;
	char fname[128];
	char aline[1024],skip[256];
	COLOUR c,red = {1,0,0};
	XYZ p;
	double r;
	FILE *fptr;
	XYZ themin = {1e32,1e32,1e32}, themax = {-1e32,-1e32,-1e32},themid;
	double rmin = 1e32,rmax = -1e32;

	// Command line
	if (argc < 2) {
		fprintf(stderr,"Usage: %s [options] povfilename\n",argv[0]);
		fprintf(stderr,"Options:\n");
		fprintf(stderr,"    -s n    scale factor\n");
		exit(-1);
	}
	for (i=1;i<argc;i++) {
		if (strcmp(argv[i],"-s") == 0)
			scale = atof(argv[i+1]);
	}
	strcpy(fname,argv[argc-1]);

	// Read sphere data
	fprintf(stderr,"Processing file \"%s\"\n",fname);
	if ((fptr = fopen(fname,"r")) == NULL) {
		fprintf(stderr,"Failed to open input file \"%s\"\n",fname);
		exit(-1);
	}
	while (ReadUntil(fptr,'\n',aline)) {

		// Remove characters we don't want
		for (i=0;i<strlen(aline);i++) {
			if (aline[i] == '{' || aline[i] == '<' || aline[i] == ',')
				aline[i] = ' ';
         if (aline[i] == '}' || aline[i] == '>')
            aline[i] = ' ';
		}

		// Detect sphere lines
		if (strstr(aline,"sphere") != NULL) {
			if (sscanf(aline,"%s %lf %lf %lf %lf",skip,&p.x,&p.y,&p.z,&r) != 5) {
				fprintf(stderr,"Unexpected sphere line encountered\n");
				exit(-1);
			}
			spheres = realloc(spheres,(nspheres+1)*sizeof(SPHERE));
			spheres[nspheres].p = p;
			spheres[nspheres].r = r;
			spheres[nspheres].c = red;
			nspheres++;
		}

      // Detect pigment lines
      if (strstr(aline,"pigment") != NULL) {
         if (sscanf(aline,"%s %s %s %lf %lf %lf",skip,skip,skip,&c.r,&c.g,&c.b) != 6) {
            fprintf(stderr,"Unexpected pigment line encountered\n");
            exit(-1);
         }
			if (nspheres > 0)
         	spheres[nspheres-1].c = c;
      }
	}
	fclose(fptr);
	fprintf(stderr,"Found %d spheres\n",nspheres);
   for (i=0;i<nspheres;i++) {
      themin.x = MIN(themin.x,spheres[i].p.x);
      themin.y = MIN(themin.y,spheres[i].p.y);
      themin.z = MIN(themin.z,spheres[i].p.z);
      themax.x = MAX(themax.x,spheres[i].p.x);
      themax.y = MAX(themax.y,spheres[i].p.y);
      themax.z = MAX(themax.z,spheres[i].p.z);
      rmin = MIN(rmin,spheres[i].r);
      rmax = MAX(rmax,spheres[i].r);
   }
   fprintf(stderr,"Model dimensions\n");
   fprintf(stderr,"   %g < x < %g\n",themin.x,themax.x);
   fprintf(stderr,"   %g < y < %g\n",themin.y,themax.y);
   fprintf(stderr,"   %g < z < %g\n",themin.z,themax.z);
   fprintf(stderr,"   %g < r < %g\n",rmin,rmax);

	// Center on origin
	themid.x = (themin.x + themax.x) / 2;
   themid.y = (themin.y + themax.y) / 2;
   themid.z = (themin.z + themax.z) / 2;
   for (i=0;i<nspheres;i++) {
      spheres[i].p.x -= themid.x;
      spheres[i].p.y -= themid.y;
      spheres[i].p.z -= themid.z;
	}

	// Scale
	for (i=0;i<nspheres;i++) {
		spheres[i].p.x *= scale;
      spheres[i].p.y *= scale;
      spheres[i].p.z *= scale;
      spheres[i].r *= scale;
	}

	// Report final size
	themin.x = spheres[0].p.x;
   themin.y = spheres[0].p.y;
   themin.z = spheres[0].p.z;
   themax.x = spheres[0].p.x;
   themax.y = spheres[0].p.y;
   themax.z = spheres[0].p.z;
	rmin = spheres[0].r;
	rmax = spheres[0].r;
	for (i=1;i<nspheres;i++) {
		themin.x = MIN(themin.x,spheres[i].p.x);
      themin.y = MIN(themin.y,spheres[i].p.y);
      themin.z = MIN(themin.z,spheres[i].p.z);
      themax.x = MAX(themax.x,spheres[i].p.x);
      themax.y = MAX(themax.y,spheres[i].p.y);
      themax.z = MAX(themax.z,spheres[i].p.z);
		rmin = MIN(rmin,spheres[i].r);
      rmax = MAX(rmax,spheres[i].r);
	}
	fprintf(stderr,"Final dimensions\n");
	fprintf(stderr,"   %g < x < %g\n",themin.x,themax.x);
   fprintf(stderr,"   %g < y < %g\n",themin.y,themax.y);
   fprintf(stderr,"   %g < z < %g\n",themin.z,themax.z);
   fprintf(stderr,"   %g < r < %g\n",rmin,rmax);

   // Export as wrl
	for (i=0;i<strlen(fname);i++)
		if (fname[i] == '.')
			fname[i] = '\0';
	strcat(fname,".wrl");
	if ((fptr = fopen(fname,"w")) == NULL) {
		fprintf(stderr,"Failed to open outout file \"%s\"\n",fname);
		exit(-1);
	}
   WRLHeader(fptr,argv[0],sqrt(themax.x*themax.x+themax.y*themax.y+themax.z*themax.z));
	for (i=0;i<nspheres;i++) {
		WRLSphere(fptr,spheres[i].p,spheres[i].r,spheres[i].c);
	}
	fclose(fptr);

   // Export as geom
   for (i=0;i<strlen(fname);i++)
      if (fname[i] == '.')
         fname[i] = '\0';
   strcat(fname,".geom");
   if ((fptr = fopen(fname,"w")) == NULL) {
      fprintf(stderr,"Failed to open outout file \"%s\"\n",fname);
      exit(-1);
   }
   for (i=0;i<nspheres;i++) {
      fprintf(fptr,"s %g %g %g %g %g %g %g\n",
			spheres[i].p.x,spheres[i].p.y,spheres[i].p.z,spheres[i].r,
			spheres[i].c.r,spheres[i].c.g,spheres[i].c.b);
   }
   fclose(fptr);

	exit(0);
}

void WRLSphere(FILE *fptr,XYZ p,double r,COLOUR c)
{
   fprintf(fptr,"Transform {\n");
   fprintf(fptr," translation %g,%g,%g\n",p.x,p.y,p.z);
   fprintf(fptr," children [\n");
   fprintf(fptr,"  Shape {\n");
   fprintf(fptr,"   appearance Appearance {\n");
   fprintf(fptr,"    material Material {\n");
   fprintf(fptr,"     diffuseColor %g %g %g\n",c.r,c.g,c.b);
   fprintf(fptr,"    }\n");
   fprintf(fptr,"   }\n");
   fprintf(fptr,"   geometry Sphere {\n");
   fprintf(fptr,"    radius %g\n",r);
   fprintf(fptr,"   }\n");
   fprintf(fptr,"  }\n");
   fprintf(fptr," ]\n");
   fprintf(fptr,"}\n");
}

/*
   WRL header
   Assume the object is at the origin
*/
void WRLHeader(FILE *fptr,char *comment,double dist)
{
   fprintf(fptr,"#VRML V2.0 utf8\n");

   fprintf(fptr,"WorldInfo {\n");
   fprintf(fptr," title \"%s\"\n",comment);
   fprintf(fptr," info [ \"By Paul Bourke\" ]\n");
   fprintf(fptr,"}\n");

   fprintf(fptr,"NavigationInfo {\n");
   fprintf(fptr," type [\"EXAMINE\",\"ANY\"]\n");
   fprintf(fptr," headlight TRUE\n");
   fprintf(fptr," visibilityLimit 0.0\n");
   fprintf(fptr," speed 1.0\n");
   fprintf(fptr,"}\n");

   fprintf(fptr,"DEF DefaultView Viewpoint {\n");
   fprintf(fptr," position 0 0 %g\n",dist);
   fprintf(fptr," description \"Default view\"\n");
   fprintf(fptr," fieldOfView %g\n",M_PI/4);
   fprintf(fptr,"}\n");
}

/*
  Read until a particular character is encountered
*/
int ReadUntil(FILE *fptr,int find,char *s)
{
  int c,i = 0;

  i = 0;
  s[i] = 0;
  while ((c = fgetc(fptr)) != find && c != EOF) {
    s[i] = c;
    i++;
    s[i] = '\0';
  }

  if (c == EOF)
    return(FALSE);
  return(TRUE);
}