/** 
* @file testImageNetBinaryBruteForce.cpp
* @brief perform ImageNet tests with binary tasks for OCC
* @author Alexander Lütz
* @date 23-05-2012 (dd-mm-yyyy)

*/
#include "core/basics/Config.h"
#include "core/vector/SparseVectorT.h"

#include "vislearning/cbaselib/ClassificationResults.h"
#include "vislearning/baselib/ProgressBar.h"

#include "fast-hik/tools.h"
#include "fast-hik/MatFileIO.h"
#include "fast-hik/ImageNetData.h"

using namespace std;
using namespace NICE;
using namespace OBJREC;

double measureDistance ( const NICE::SparseVector & a, const NICE::SparseVector & b, const double & sigma = 2.0, const bool & verbose = false)
{
  double inner_sum(0.0);

  double s;
  double d;    
  
  //this is the first version, where we needed on average 0.017988 s for each test sample
//   std::set<int> set_a;
//   
//   
//   for ( NICE::SparseVector::const_iterator i = a.begin(); i != a.end(); i++ )
//   {
//     double u (i->second);
//     double v (b.get(i->first));
//     s = ( u + v );
//     if ( fabs(s) < 10e-6 ) continue;
//     d = u-v;
//     inner_sum += d*d;
//     set_a.insert(i->first);
//   }
//   
//   for ( NICE::SparseVector::const_iterator i = b.begin(); i != b.end(); i++ )
//   {
//     if (set_a.find(i->first) != set_a.end()) //already worked on in first loop
//       continue;
//     
//     double u (i->second);
//     if ( fabs(u) < 10e-6 ) continue;
//     inner_sum += u*u;
//   }
  
  
  //new version, where we needed on average 0.001707 s for each test sample
  NICE::SparseVector::const_iterator aIt = a.begin();
  NICE::SparseVector::const_iterator bIt = b.begin();
   
  while ( (aIt != a.end()) && (bIt != b.end()) )
  {
//     std::cerr << "a: " << aIt->first << " b: " << bIt->first << std::endl;
    if (aIt->first == bIt->first)
    {
      s  = ( aIt->second + bIt->second );
//       if (!  fabs(s) < 10e-6 ) //for numerical reasons
//       {
        d = ( aIt->second - bIt->second );      
        inner_sum += d * d;
//       }
      aIt++;
      bIt++;
    }
    else if ( aIt->first < bIt->first)
    {
//       if (! fabs(aIt->second) < 10e-6 )
//       {
        inner_sum += aIt->second * aIt->second;
//       }
      aIt++;      
    }
    else
    {
//       if (! fabs(bIt->second) < 10e-6 )
//       {
        inner_sum += bIt->second * bIt->second;
//       }
      bIt++;       
    }
  }
  
  //compute remaining values, if b reached the end but not a
  while (aIt != a.end())
  {
    inner_sum += aIt->second * aIt->second;
    aIt++; 
  }
  
  //compute remaining values, if a reached the end but not b
  while (bIt != b.end())
  {
    inner_sum += bIt->second * bIt->second;
    bIt++; 
  }  
  
  if (verbose)
    std::cerr << "inner_sum before /= (2.0*sigma*sigma) " << inner_sum << std::endl;

  inner_sum /= (2.0*sigma*sigma);
  
  if (verbose)
    std::cerr << "inner_sum after /= (2.0*sigma*sigma) " << inner_sum << std::endl;
  double expValue = exp(-inner_sum);
  if (verbose)
    std::cerr << "resulting expValue " << expValue << std::endl;

  return exp(-inner_sum); //expValue;
}


/** 
    test the basic functionality of fast-hik hyperparameter optimization 
*/
int main (int argc, char **argv)
{   
  std::set_terminate(__gnu_cxx::__verbose_terminate_handler);

  Config conf ( argc, argv );
  string resultsfile = conf.gS("main", "results", "results.txt" );
  int positiveClass = conf.gI("main", "positive_class");
  double noise = conf.gD("main", "noise", 0.01);
  double kernelSigma = conf.gD("main", "kernelSigma", 2.0);
  int nrOfExamplesPerClass = conf.gI("main", "nrOfExamplesPerClass", 50);
  nrOfExamplesPerClass = std::min(nrOfExamplesPerClass, 100); // we do not have more than 100 examples per class
  int nrOfClassesToConcidere = conf.gI("main", "nrOfClassesToConcidere", 1000);
  nrOfClassesToConcidere = std::min(nrOfClassesToConcidere, 1000); //we do not have more than 1000 classes

  std::cerr << "Positive class is " << positiveClass << std::endl;
  
  std::vector<SparseVector> trainingData;
  NICE::Vector y;
  
  std::cerr << "Reading ImageNet data ..." << std::endl;
  bool imageNetLocal = conf.gB("main", "imageNetLocal" , false);
  string imageNetPath;
  if (imageNetLocal)
    imageNetPath = "/users2/rodner/data/imagenet/devkit-1.0/";
  else
    imageNetPath = "/home/dbv/bilder/imagenet/devkit-1.0/";

  ImageNetData imageNetTrain ( imageNetPath + "demo/" );

  imageNetTrain.preloadData( "train", "training" );
  trainingData = imageNetTrain.getPreloadedData();
  y = imageNetTrain.getPreloadedLabels();
    
  std::cerr << "Reading of training data finished" << std::endl;
  std::cerr << "trainingData.size(): " << trainingData.size() << std::endl;
  std::cerr << "y.size(): " << y.size() << std::endl;
  
  std::cerr << "Reading ImageNet test data files (takes some seconds)..." << std::endl;
  ImageNetData imageNetTest ( imageNetPath + "demo/" );
  imageNetTest.preloadData ( "val", "testing" );
  imageNetTest.loadExternalLabels ( imageNetPath + "data/ILSVRC2010_validation_ground_truth.txt" );  
  
  double OverallPerformance(0.0);
  
  for (int cl = 0; cl < nrOfClassesToConcidere; cl++)
  {
    std::cerr << "run for class " << cl << std::endl;
    // ------------------------------ TRAINING ------------------------------
  
    NICE::Vector matrixDInv (nrOfExamplesPerClass, 0.0);
    //compute D 
    //start with adding some noise, if necessary
    if (noise != 0.0)
      matrixDInv.set(noise);
    else
      matrixDInv.set(0.0);
    
    std::cerr << "set matrixDInv to noise - now compute the scores for this special type of matrix" << std::endl;
    
    if ( cl == 0)
    {
      std::cerr << "print first training example of class zero: " << std::endl;
      trainingData[0] >> std::cerr;
    }
    
    //now sum up all entries of each row in the original kernel matrix
    double kernelScore(0.0);
    for (int i = cl*100; i < cl*100+nrOfExamplesPerClass; i++)
    {
//       if ( (i % 50) == 0)
        std::cerr << i << " / " << nrOfExamplesPerClass << std::endl;
      for (int j = i; j < cl*100+nrOfExamplesPerClass; j++)
      {
//         std::cerr <<  j << " / " << nrOfExamplesPerClass << std::endl;
        if ( (cl == 0) && (i == 0))
        {
          kernelScore = measureDistance(trainingData[i],trainingData[j], kernelSigma, true /*verbose*/);
        }
        else
          kernelScore = measureDistance(trainingData[i],trainingData[j], kernelSigma);
        if (kernelScore == 0.0) std::cerr << "score of zero for examples " << i << " and "  << j << std::endl;
        matrixDInv[i-cl*100] += kernelScore;
        if (i != j)
          matrixDInv[j-cl*100] += kernelScore; 
      }
    }  
    
    std::cerr << "invert the main diagonal" << std::endl;
    
    //compute its inverse
    for (int i = 0; i < nrOfExamplesPerClass; i++)
    {
      matrixDInv[i] = 1.0 / matrixDInv[i];
    }
    
    std::cerr << "resulting D-Vector (or matrix :) ) " << std::endl;
    std::cerr << matrixDInv << std::endl;
    
    std::cerr << "training done - now perform the evaluation" << std::endl;


    // ------------------------------ TESTING ------------------------------
   
    ClassificationResults results;
    std::cerr << "Classification step ... with " << imageNetTest.getNumPreloadedExamples() << " examples" << std::endl;
    ProgressBar pb;
    for ( uint i = 0 ; i < (uint)imageNetTest.getNumPreloadedExamples(); i++ )
    {
      pb.update ( imageNetTest.getNumPreloadedExamples() );

      const SparseVector & svec = imageNetTest.getPreloadedExample ( i );
//       SparseVector svec = imageNetTest.getPreloadedExample ( i );
      
      if ( i == 0)
      {
        std::cerr << "print first test example: " << std::endl;
        std::cerr << "this is of class " << (int)imageNetTest.getPreloadedLabel ( i ) << std::endl;
//         svec >> std::cerr; 
        svec.store(std::cerr);
      }      
      
      double kernelSelf (measureDistance(svec,svec, kernelSigma) ) ;
      NICE::Vector kernelVector (nrOfExamplesPerClass, 0.0);
      
      for (int j = 0; j < nrOfExamplesPerClass; j++)
      {
        kernelVector[j] = measureDistance(trainingData[j+cl*100],svec, kernelSigma);
      }
      
      if ( i == 0)
      {
        std::cerr << "print first kernel vector: " << kernelVector << std::endl;
      }
      
    
      NICE::Vector rightPart (nrOfExamplesPerClass);
      for (int j = 0; j < nrOfExamplesPerClass; j++)
      {
        rightPart[j] = kernelVector[j] * matrixDInv[j];
      }

      double uncertainty = kernelSelf - kernelVector.scalarProduct ( rightPart );
      
      FullVector scores ( 2 );
      scores[0] = 0.0;
      scores[1] = 1.0 - uncertainty;

      ClassificationResult r ( scores[1]<0.5 ? 0 : 1, scores );    
      
      // set ground truth label
      r.classno_groundtruth = (((int)imageNetTest.getPreloadedLabel ( i )) == positiveClass) ? 1 : 0;
      
//       std::cerr << "scores: " << std::endl;
//       scores >> std::cerr;
//       std::cerr << "gt: " <<  r.classno_groundtruth << " -- " << r.classno << std::endl;
      
      results.push_back ( r );
    }

//     std::cerr << "Writing results to " << resultsfile << std::endl;
//     results.writeWEKA ( resultsfile, 1 );
    double perfvalue = results.getBinaryClassPerformance( ClassificationResults::PERF_AUC );

    std::cerr << "Performance: " << perfvalue << std::endl;
    
    OverallPerformance += perfvalue;    
  }
  
  OverallPerformance /= nrOfClassesToConcidere;
  
  std::cerr << "overall performance: " << OverallPerformance << std::endl;
  
  return 0;
}