// Compile with, for example:
//
// Linux:
//
// g++ -Wall -g -o rigol2dat rigol2dat.C
//
// Mingw cross compile:
//
// i586-mingw32msvc-g++ rigol2dat.C -o rigol2dat.exe


#include <stdio.h>
#include <stdint.h>
#include <string.h>
#include <string>

using namespace std;

#define MAX_PTS 524288*2

int main(int argc, char **argv)
{
  uint32_t npts;
  uint64_t time_scale;
  int64_t time_delay;
  uint8_t ch1rec;
  uint8_t ch2rec;

  uint32_t ch1sc;
  int16_t ch1pos;
  uint32_t ch2sc;
  int16_t ch2pos;
  
  uint8_t data[MAX_PTS]; // biggest size from our rigol
  
  int nread;
  
  // Stuff in real units

  double trace_length_sec;
  double ch1sc_v;
  double ch1pos_v;
  double ch2sc_v;
  double ch2pos_v;

  char filename[1024];
  strncpy(filename, argv[1], 1024);
  char basename[1024];
  strcpy(basename, filename);
  char *p = strchr(basename, '.');
  *p = 0;
  string outname;

  FILE *fp = fopen(argv[1], "r");
  FILE *out;

  fseek(fp, 28, SEEK_SET);
  fread(&npts, sizeof(npts), 1, fp);
  fprintf(stderr, "npts: %d\n", npts);
  if (npts > MAX_PTS)
    { fprintf(stderr, "Too many points: %d > %d!\n", npts, MAX_PTS); exit(-1); }

  fseek(fp, 84, SEEK_SET);
  fread(&time_scale, sizeof(time_scale), 1, fp);
  fprintf(stderr, "time_scale: %lld ps = %e s\n", time_scale, 1.0*time_scale/1e12);

  // The next int64
  //fseek(fp, 84, SEEK_SET);
  fread(&time_delay, sizeof(time_delay), 1, fp);
  fprintf(stderr, "time_delay: %lld ps = %e s\n", time_delay, 1.0*time_scale/1e12);
  
  fseek(fp, 49, SEEK_SET);
  fread(&ch1rec, sizeof(ch1rec), 1, fp);
  fprintf(stderr, "ch1rec: %d\n", ch1rec);

  fseek(fp, 73, SEEK_SET);
  fread(&ch2rec, sizeof(ch2rec), 1, fp);
  fprintf(stderr, "ch2rec: %d\n", ch2rec);

  fseek(fp, 36, SEEK_SET);
  fread(&ch1sc, sizeof(ch1sc), 1, fp);
  fprintf(stderr, "ch1sc: %d\n", ch1sc);

  fseek(fp, 40, SEEK_SET);
  fread(&ch1pos, sizeof(ch1pos), 1, fp);
  fprintf(stderr, "ch1pos: %d\n", ch1pos);

  fseek(fp, 60, SEEK_SET);
  fread(&ch2sc, sizeof(ch2sc), 1, fp);
  fprintf(stderr, "ch2sc: %d\n", ch2sc);

  fseek(fp, 64, SEEK_SET);
  fread(&ch2pos, sizeof(ch2pos), 1, fp);
  fprintf(stderr, "ch2pos: %d\n", ch2pos);

  // Now get things in real units

  ch1sc_v = 1e-6*ch1sc;
  ch1pos_v = 1.0*ch1pos*ch1sc_v;

  ch2sc_v = 1e-6*ch2sc;
  ch2pos_v = 1.0*ch2pos*ch2sc_v;
  
  trace_length_sec = 1.0*time_scale/1e12 * 12;

  fprintf(stderr, "\nReal units:\n\n"
	  "ch1sc_v: %e\n"
	  "ch1pos_v: %e\n"
	  "ch2sc_v: %e\n"
	  "ch2pos_v: %e\n"
	  "trace_sec: %e\n",
	  ch1sc_v, ch1pos_v,
	  ch2sc_v, ch2pos_v,
	  trace_length_sec);

  if (ch1rec)
    {
      outname = basename;
      outname += ".1.dat";
      out = fopen(outname.c_str(), "w");

      fseek(fp, 272, SEEK_SET);
      nread = fread(data, sizeof(data[0]), npts, fp);
      if (nread != npts)
	{ fprintf(stderr, "Short read: nread %d is not same as npts %d", nread, npts); exit(-1); }

      for (int i=0; i<npts; i++)
	fprintf(out, "%e %e\n", 
		trace_length_sec*i/(npts-1), 
		ch1sc_v*(100.0-data[i]+1)/25.0-ch1pos_v);
      
      fclose(out);
    }

  if (ch2rec)
    {
      outname = basename;
      outname += ".2.dat";
      out = fopen(outname.c_str(), "w");

      fseek(fp, 272+npts, SEEK_SET);
      nread = fread(data, sizeof(data[0]), npts, fp);
      if (nread != npts)
	{ fprintf(stderr, "Short read: nread %d is not same as npts %d", nread, npts); exit(-1); }     

      for (int i=0; i<npts; i++)
	fprintf(out, "%e %e\n", 
		trace_length_sec*i/(npts-1), 
		ch2sc_v*(100.0-data[i])/25.0-ch2pos_v);
      
      fclose(out);
    }
  
  fclose(fp);
}