#include "cluster_reader.h"

int read_clusters(FILE* fp, int64_t n_clusters, Cluster* buf, int *n_left){
  printf("Item size: %lu n_clusters: %lld, n_left: %d\n", sizeof(Cluster), n_clusters,*n_left);
    int iframe=0, nph=*n_left;
    size_t n_read=0, nph_read=0, nn=*n_left, nr=0;
    //n_left=n_clusters;
    
    //read photons left from previous frame
    if (nph) {
	if (nph>n_clusters-nph_read)
	  nn=n_clusters-nph_read;
	else 
	  nn=nph;
	//printf("* %d %d %d %d\n",iframe,nph,nn,n_left);
      	nr += fread((void*)(buf+nph_read), sizeof(Cluster), nn, fp);
	n_read+=nr/sizeof(Cluster);
	nph_read+=nn;
	*n_left=nph-nn;
    } 
    if (nph_read<n_clusters) {
    //keep on reading frames and photons until reaching n_clusters
    while (fread(&iframe, sizeof(iframe), 1, fp)) {
      if (fread(&nph, sizeof(nph), 1, fp) ) {
	if (nph>n_clusters-nph_read)
	  nn=n_clusters-nph_read;
	else 
	  nn=nph;
	
	//printf("%d %d %d %d\n",iframe,nph,nr,n_left);
	nr += fread((void*)(buf+nph_read), sizeof(Cluster), nn, fp);
	//printf("%d %d %d %d\n",iframe,nph,nr,n_left);
	n_read+=nr;
	nph_read+=nn;
	*n_left=nph-nn;
      }
      if (nph_read>=n_clusters)
	break;
    }
    }
    // size_t n_read = fread(buf, sizeof(Cluster), n_clusters, fp);
    printf("Read: %zu items %zu left %d\n", nph_read, n_read,*n_left);
    return nph_read;
}