#include <fstream>
#include <TH1F.h>
#include <TCanvas.h>
#include <TROOT.h>

//#define PEDESTAL_RUN 1
//#define HTRACE_IF_OVER 50
//#define RATE_TOO_HIGH 3

void viewer(char *filename)
{
   ifstream datafile(filename,std::ios::in);
   if (!datafile.is_open()) {
      std::cerr << "Error in viewer -- unable to open input file "
                << filename << std::endl;
      return;
   }
   TH1F *hamp = gROOT->FindObject("hamp");
   if (hamp == 0) {
      hamp = new TH1F("hamp","peak height maximum",500,0,500);
   }
   TH1F *hampa = gROOT->FindObject("hampa");
   if (hampa == 0) {
      hampa = new TH1F("hampa","peak height average",500,0,500);
   }
   TH1F *hampe = gROOT->FindObject("hampe");
   if (hampe == 0) {
      hampe = new TH1F("hampe","even channels",500,0,500);
   }
   TH1F *hampo = gROOT->FindObject("hampo");
   if (hampo == 0) {
      hampo = new TH1F("hampo","odd channels",500,0,500);
   }
   int count=0;
   int drop_count=0;
   int event_time_sec=0;
   int events_per_sec=0;
   int events_this_sec=0;
   while (!datafile.eof()) {
      int reclen;
      datafile.read((char*)&reclen,4);
      short int data[1000000];
      datafile.read((char*)&data,reclen*2);
      if (!datafile.good() || reclen < 100) {
         break;
      }

#if RATE_TOO_HIGH
      if (data[1] == event_time_sec) {
         ++events_this_sec;
      }
      else {
         events_per_sec = events_this_sec;
         events_this_sec = 1;
         event_time_sec = data[1];
      }
      if (events_per_sec >= RATE_TOO_HIGH ||
          events_this_sec >= RATE_TOO_HIGH)
      {
         ++drop_count;
         if (drop_count/1000*1000 == drop_count) {
            std::cout << "trace " << drop_count << " dropped for excess rate"
                      << std::endl;
         }
         continue;
      }
#endif

      count++;
      if (count/1000*1000 == count) {
         std::cout << "trace " << count << " found: "
                   << reclen << " samples recorded"
                   << std::endl;
      }

      int window = 24;

#if PEDESTAL_RUN
      int i0 = window+4; // this starts at window 1
      int iend = reclen-window-2;
#else
      int i0 = 110; // this finds the trigger channel
      int iend = 110; // this restricts analysis to the trigger window
#endif

      while (i0 <= iend) {
         float vbase=0;
         float vbase0=0;
         float vbase1=0;
         float vmin=999;
         float vpeak=0;
         for (int i=0; i<window; ++i) {
            vbase += data[i+i0-window];
            if ((i+i0)/2*2 == i+i0) {
               vbase0 += data[i+i0-window];
            }
            else {
               vbase1 += data[i+i0-window];
            }
            if (data[i+i0] < vmin && i+i0+2 < reclen) {
               vmin = data[i+i0];
               vpeak = data[i+i0-1]+data[i+i0]+data[i+i0+1]+data[i+i0+2];
               vpeak /= 4;
            }
         }
         vbase /= window;
         vbase0 /= window/2.;
         vbase1 /= window/2.;
         hamp->Fill(vbase-vmin);
         hampa->Fill(vbase-vpeak);
         hampe->Fill(vbase0);
         hampo->Fill(vbase1);
         i0 += window;

#ifdef HTRACE_IF_OVER
         if (vbase-vpeak > HTRACE_IF_OVER) {
            char name[10];
            char title[20];
            sprintf(name,"e%d",count);
            sprintf(title,"event %d",count);
            TH1F *htrace = new TH1F(name,title,reclen,0,reclen);
            for (int ibin=1; ibin<=reclen; ++ibin) {
               if (ibin > 4) {
                  htrace->SetBinContent(ibin,double(data[ibin]));
               }
               else {
                  htrace->SetBinContent(ibin,0);
               }
            }
            TCanvas *c1 = gROOT->FindObject("c1");
            if (c1 == 0) {
               c1 = new TCanvas("c1","c1",0,0,500,500);
            }
            htrace->Draw();
            c1->Update();
std::cout << "vbase,vpeak,i0,reclen=" << vbase << "," << vpeak << "," << i0 << "," << reclen << std::endl;
         }
#endif

      }
   }
}