#include "stressThreads.h"

ClassImp(stressThreads);



TFile**   stressThreads::files=NULL;
TTree**   stressThreads::trees=NULL;
int*      stressThreads::thedata=NULL;
int**     stressThreads::threadInstructions=NULL;
int       stressThreads::loopsPerThread=0;
TThread** stressThreads::threads=NULL;

stressThreads::stressThreads(int nThreads, int loopsPerThread_){
   
   loopsPerThread = loopsPerThread_;
   
   files = new TFile*[nThreads];
   trees = new TTree*[nThreads];
   thedata = new int[nThreads];
   threads = new TThread*[nThreads];
   threadInstructions = new int*[nThreads];
   
   
   // create the files, trees, threads etc
   for (int i=0; i<nThreads; i++){
      files[i] = new TFile(Form("file_%d.root", i),"recreate");
      trees[i] = new TTree(Form("tree_%d", i),Form("tree_%d", i)) ;
      trees[i]->SetDirectory(files[i]);
      trees[i]->Branch("data", &(thedata[i]), "data/I");
      // trees[i]->SetAutoSave(10000);
      threadInstructions[i] = new int[1];
      threadInstructions[i][0] = i;// just the thread index
      threads[i] = new TThread(Form("thread_%d", i), loop, (void*)threadInstructions[i]);
   }
   
   // Make sure the meta is correctly set before starting the threads.
   TFile *tempFile = TFile::Open("/var/tmp/mytemp.root","RECREATE");
   TTree *tempTree = new TTree("temp","temp");
   int val = 0;
   tempTree->Branch("data",&val);
   tempTree->Fill();
   tempTree->Write();
   tempFile->Write();
   delete tempFile;
   gSystem->Unlink("/var/tmp/mytemp.root");
   gDirectory = 0;
   
   cout<<"running"<<endl;
   for (int i=0; i<nThreads; i++)
      threads[i]->Run();
   
   for (int i=0; i<nThreads; i++)
      threads[i]->Join();
   for (int i=0; i<nThreads; i++) {
      files[i]->cd();
      files[i]->Write();
      delete files[i];
   }
   cout<<"done"<<endl;
}


// this function gets multithreaded
void* stressThreads::loop(void* p){
   int* instruction = (int*)p;
   int threadIndex = instruction[0];
   
   // simple loop to fill the tree
   for (int i=0; i<loopsPerThread; i++){
      thedata[threadIndex]=0;
      trees[threadIndex]->Fill();
   }
   
   //write and close
   //trees[threadIndex]->AutoSave("flushbaskets");
   
   return 0;
}