#include "type_hyd.h"
#include "varext.h"

extern int dcmp;
extern list_m_h *lmh_start;

void Get_Fmt(void)
{
fpos_t CurrPos;
short int min,len,year,hd_size;
main_head_o old_h;
main_head_3 mh3;
struct tm *tm3;


if ( (headfil=fopen(head_fil,"rb"))==NULL ){
   printf("could not open %s \n",head_fil);
   perror("");
   exit(0);
   }

CurrPos=4L;
fsetpos(headfil,&CurrPos);

for (min=1;min<1442;min++){
   if(fread(&CurrPos,4,1,headfil)!=1){
      if (feof) {
         printf("min=%d EOF .... ",min);
         exit(0);
         }
      printf("min=%d\n",min);
      printf("Could not read position from headfil !!!\n");
      perror("");
      exit(0);
      }
   }

if(fread(&oldlen,2,1,headfil)!=1){
   printf("timlist: Could not read oldlen from headfil !!!\n");
   perror("");
   exit(0);
   }

CurrPos=0L;
fsetpos(headfil,&CurrPos);
CurrPos=5770L;
fsetpos(headfil,&CurrPos);

while(1){
   if (fread(&len,2,1,headfil)!=1){
     if (feof) break;
     else perror ("gethyd02:");
     }

   if (len==(-1*SIZE_MAINH_O)){
     old_h.indic=len;
     if (fread(&old_h.len_prev,SIZE_MAINH_O-2,1,headfil)!=1){
       fprintf(stderr," could not read main header ! \n");
       perror("gethyd03:");
       exit(0);
       }
     memcpy(&main_h.indic,&old_h.indic,30);
     main_h.HBL=old_h.DELTA_H;
     main_h.HBR=old_h.DELTA_H;
     main_h.HFR=old_h.DELTA_H;
     memcpy(&main_h.gate1,&old_h.gate1,30);
     base_frequ=main_h.line_frequ;
     tm3=gmtime(&main_h.main_time);
   }

   else if (len==(-1*SIZE_MAINH_3)){
     main_h.indic=len;
     if (fread(&mh3.len_prev,SIZE_MAINH_3-2,1,headfil)!=1){
       fprintf(stderr," could not read main header ! \n");
       perror("gethyd03:");
       exit(0);
       }
     base_frequ=mh3.line_frequ;
     if ((base_frequ>34089)&&(base_frequ<34091)){
       base_frequ= (1193180./35.);
       }
     tm3=gmtime(&mh3.main_time);
     memcpy(&main_h.indic,&mh3.indic,42);
     main_h.mid_pix=256;
     memcpy(&main_h.gate1,&old_h.gate1,30);
     }

   else if (len==(-1*SIZE_MAINH_4)){
     main_h.indic=len;
     if (fread(&main_h.len_prev,SIZE_MAINH_4-2,1,headfil)!=1){
       fprintf(stderr," could not read main header ! \n");
       perror("gethyd03:");
       exit(0);
       }
     base_frequ=main_h.line_frequ;
     tm3=gmtime(&main_h.main_time);
     }

   year=1900+tm3->tm_year;
   hd_size=-1*len;

/*
   printf("file       = %s \n",argv[1]);
   printf("year       = %d \n",year);
   printf("SIZE_MAINH = %d \n",hd_size);
   printf("base_frequ = %lf \n",base_frequ);
   printf("oeu_nr     = %d \n",main_h.oeu_nr);
   printf("format     = %d \n",main_h.format);
   printf("dat_gen    = %d \n",main_h.dat_gen);
   printf("dat_rev    = %d \n",main_h.dat_rev);
*/

   fomt=0;
   if (year<=1995){
     size_mainh=SIZE_MAINH_O;
     size_pixh=SIZE_PIXH_O;
     fomt=1;
     }
   else{
     if (hd_size==64){
       fomt=2;
       size_mainh=hd_size;
       size_pixh=SIZE_PIXH_3;
       }

     if (hd_size==72){
       fomt=3;
       size_mainh=hd_size;
       size_pixh=SIZE_PIXH_3;
       }

     if (hd_size==74){
       fomt=4;
       size_mainh=hd_size;
       size_pixh=SIZE_PIXH_4;
       }
     }

   if (!fomt){
     printf("could not determine data format \n");
     exit(0);
     }

   }


 
rewind(headfil);
}