#ifndef __JCOMPAREHISTOGRAMS__JTESTCHI2_2D__
#define __JCOMPAREHISTOGRAMS__JTESTCHI2_2D__

#include <istream>
#include <ostream>
#include "JCompareHistograms/JTest_t.hh"
#include "JCompareHistograms/JTestChi2_t.hh"


/**
 * \author rgruiz
 */
namespace JCOMPAREHISTOGRAMS {

  /**
   * Implementation of the Chi2 test for 2D histograms.\n
   * This class is derived from the abstract class JTest_t(). For a general description of the implementation of this and other tests derived from JTest_t(), see its documentation.\n
   * The parameter slice() can have the values x, X, y or Y. The histograms are sliced along the corresponding axis, and the JChi2Test() test is applied to each slice.\n 
   * The input parameter threshold(), is used to evaluate whether the test is passed or failed for each slice.\n
   * The evaluation is done by comparing the threshold() value with the result produced by JChi2Test(). The output of JChi2Test() is a p-value.\n 
   * The parameter threshold() should therefore be a real value between 0 and 1.
   */
  class JTestChi2_2D: 
    public JTest_t,
    public JTestChi2_t
  { 
  public:
  
    /**
     * Default constructor.
     */  
    JTestChi2_2D() :
      JTest_t("Chi2_2D", "p-Value(chi2)"),
      JTestChi2_t()
    {}
  
    /**
     * Read test parameters from input.
     *
     * \param  in            input stream
     * \return               input stream
     */
    std::istream& read(std::istream& in) override{ 
      return in >> threshold >> failuresThreshold >> slice >> options;
    };
  
    /**
     * Applies Chi2 test for two ROOT TH2 histograms.
     *
     * \param o1 First histogram
     * \param o2 Second histogram
     */
    void test(TObject* o1, TObject* o2) override{    

      using namespace std;
      using namespace JPP;
    
      if (!(dynamic_cast<TH2*>(o1) == NULL) && !(dynamic_cast<TH2*>(o2) == NULL)) {
	 	  
	TH2D* h1 = dynamic_cast<TH2D*>(o1);
	TH2D* h2 = dynamic_cast<TH2D*>(o2);

	if(slice == 'x' || slice == 'X' || slice == 'y' || slice == 'Y'){
	
	  JTestResult r = JChi2TestSlice(h1, h2, threshold, failuresThreshold, testName, resultType, options, slice);

	  results.push_back(r);
	
	} else {
	  ERROR ("Slice option should be: x, X, y or Y, and not " + slice);
	}
      
      } else if (!(dynamic_cast<TH1*>(o1) == NULL) && !(dynamic_cast<TH1*>(o2) == NULL)) {
	ERROR("For 1D histograms call JChi2_1D: " << o1->GetName() << endl);
      }
    };
  
  private:
    double      threshold;                         //!< threshold p-value to decide if test is passed.
    double      failuresThreshold;                 //!< threshold p-value to decide if test is passed.
    char        slice;                             //!< axis to slice.
    std::string options;                           //!< options for the ROOT chi2 test.
  };
}
  
#endif