//-*- mode: c++ -*-
#ifndef DATETIME_TEST_H_
#define DATETIME_TEST_H_

#include <cxxtest/TestSuite.h>

#include "DateTime.h"

static const double TEST_EPSILON = 1e-12;

class DateTimeTest : public CxxTest::TestSuite
{
 public:
  void testDefaultConstructor( void )
    {
      // A DateTime object initialized with no paramaters should set the MJD to 0
      DateTime epoch;
      TS_ASSERT_DELTA( epoch.getMJD(), 0.0, TEST_EPSILON);
    }

  void testMJDConstructor( void )
    {
      // A DateTime object initialized with an MJD specified should set the MJD...
      DateTime valentinesDay2008(54510.0);

      TS_ASSERT_EQUALS(valentinesDay2008.getMJD(), 54510.0);
    }

  void testYMDHMSConstructor( void )
    {
      DateTime valentinesDay2008((unsigned int) 2008,  // year
				 (unsigned int) 2,     // month
				 (unsigned int) 14,    // day 
				 (unsigned int) 0,     // hour
				 (unsigned int) 0,     // minute
				 (double) 0.0);        // second

      TS_ASSERT_EQUALS(valentinesDay2008.getMJD(), 54510.0);
    }

  void testSetMJD( void )
    {
      DateTime epochToValentinesDay2008(12345.6789);
      epochToValentinesDay2008.setMJD(54510.0);

      TS_ASSERT_EQUALS( epochToValentinesDay2008.getMJD(), 54510.0);
    }


  /** 
   * Why does testIncrement exist?
   *
   *  There once was bug (fixed in r1659) where the LFM would perform an
   *  operation (eg. file I/O or exchange data with MIX/RCM) one
   *  second earlier than it should've.  This is particularly annoying
   *  because some assumptions were made about file names.  The code
   *  would occasionally die when reading a file named
   *  
   *       1995-03-21T04-51-59Z.hdf
   * 
   *  instead of 
   * 
   *       1995-03-21T04-52-00Z.hdf
   *
   *  This test makes sure that incrementing the time (and comparing
   *  with ">=") will not have this "off by 1" error.
   */
  void testGreatOrEqual( void )
    {
      const float dt = 0.04007064;      

      DateTime start(1995, 03, 21, 11, 0, 0);
      DateTime stop(1995, 03, 21, 12, 0, 0);

      DateTime next = start;
      int iStep = 0;
      start.incrementSeconds(60.0*iStep);
      DateTime current = start;

      //cout << numeric_limits<double>::epsilon();

      while (current < stop){
	if (current >= next){
	  next = start;
	  next.incrementSeconds(60.0*iStep++);
	  TS_ASSERT_DELTA(int(current.getSecond()), 0.0, 1e-1);
	  //cout << current.getDateTimeString() << endl;
	}
	current.incrementSeconds(dt);
      }      

    }

  void testSmallSecondResolution( void )
    {
      // Make sure that the modified julian date can capture resolution to the nearest second

      // 1 second
      DateTime TT1 = DateTime(1.0/(24.0*60.0*60.0));
      // 2 seconds
      DateTime TT2 = DateTime(2.0/(24.0*60.0*60.0));
      // 3 seconds
      DateTime TT3 = DateTime(3.0/(24.0*60.0*60.0));

      //std::cout << std::endl << std::setprecision(50) << std::fixed;
      //std::cout << "\t" << 1.0/(24.0*60.0*60.0) << std::endl;
      //std::cout << (int) TT1.getSeconds() << "\t" << TT1.getMJD() << std::endl;
      //std::cout << (int) TT2.getSeconds() << "\t" << TT2.getMJD() << std::endl;
      //std::cout << (int) TT3.getSeconds() << "\t" << TT3.getMJD() << std::endl;

      TS_ASSERT_DELTA( TT1.getSeconds(), 1, TEST_EPSILON);
      TS_ASSERT_DELTA( TT2.getSeconds(), 2, TEST_EPSILON);
      TS_ASSERT_DELTA( TT3.getSeconds(), 3, TEST_EPSILON);
    }

  void testLargeSecondResolution( void )
    {
      // Check that MJD to YYYY-MM-DD HH:MM:SS obtains the correct number of seconds
      // Ensures that a bug found by Slava using the TT1,TT2,TT3 DateTimes obtains the correct number of elapsed seconds.

      // [2008-01-01] @ 04:00:02 
      DateTime TT1 = DateTime(54466.166689814817800652235746400000);
      // 59.6 seconds:           (0.000689814817800652235746400000)

      // [2008-01-01] @ 04:00:04 
      DateTime TT2 = DateTime(54466.166712962964083999395370500000);
      //61.6 seconds:            (0.000712962964083999395370500000)

      // [2008-01-01] @ 04:00:06 
      DateTime TT3 = DateTime(54466.166736111110367346554994600000);
      // 63.5999999 seconds:     (0.000736111110367346554994600000)
      
      //std::cout << std::endl << std::setprecision(50) << std::fixed;
      //std::cout << "\t" << 1.0/(24.0*60.0*60.0) << std::endl;
      //std::cout << (int) TT1.getSeconds() << "\t" << TT1.getMJD() << std::endl;
      //std::cout << (int) TT2.getSeconds() << "\t" << TT2.getMJD() << std::endl;
      //std::cout << (int) TT3.getSeconds() << "\t" << TT3.getMJD() << std::endl;

      TS_ASSERT_DELTA( TT1.getSeconds(), 2, TEST_EPSILON);
      TS_ASSERT_DELTA( TT2.getSeconds(), 4, TEST_EPSILON);
      TS_ASSERT_DELTA( TT3.getSeconds(), 6, TEST_EPSILON);
    }

  void testSetYMDHMS( void )
    {
      DateTime epochToValentinesDay2008(12345.6789);

      epochToValentinesDay2008.setYear(2008);
      epochToValentinesDay2008.setMonth(2);
      epochToValentinesDay2008.setDay(14);
      epochToValentinesDay2008.setHours(0);
      epochToValentinesDay2008.setMinutes(0);
      epochToValentinesDay2008.setSeconds(0.0);      

      TS_ASSERT_EQUALS( epochToValentinesDay2008.getMJD(), 54510.0);
    }
  
  void testGetYear( void )
    {
      DateTime date(54510.0);
      
      TS_ASSERT_EQUALS( date.getYear(), 2008);
    }

  void testGetMonth( void )
    {
      DateTime date(54510.0);
      
      TS_ASSERT_EQUALS( date.getMonth(), 2);
    }

  void testGetDay( void )
    {
      DateTime date(54510.0);
      
      TS_ASSERT_EQUALS( date.getDay(), 14);
    }

  void testGetHours( void )
    {
      DateTime date(54510.0);
      
      TS_ASSERT_EQUALS( date.getHours(), 0);
    }

  void testGetMinutes( void )
    {
      DateTime date(54510.0);
      
      TS_ASSERT_EQUALS( date.getMinutes(), 0);
    }

  void testGetSeconds( void )
    {
      DateTime date(54510.0);
      
      TS_ASSERT_EQUALS( date.getSeconds(), 0);
    }
  
  void testIncrementMJD( void )
    {
      DateTime date(0.0);
      date.incrementMJD(100.123);
      
      TS_ASSERT_EQUALS( date.getMJD(), 100.123 );
    }

  void testIncrementYear( void )
    {
      DateTime date((unsigned int) 1492,  // year
		    (unsigned int) 10,     // month
		    (unsigned int) 12,    // day 
		    (unsigned int) 12,     // hour
		    (unsigned int) 0,     // minute
		    (double) 0.0);        // second

      date.incrementYear(516);
      
      TS_ASSERT_EQUALS( date.getYear(), 2008 );
    }

  void testIncrementMonth( void )
    {
      DateTime date((unsigned int) 1492,  // year
		    (unsigned int) 10,     // month
		    (unsigned int) 12,    // day 
		    (unsigned int) 12,     // hour
		    (unsigned int) 0,     // minute
		    (double) 0.0);        // second

      date.incrementMonth(4);
      
      TS_ASSERT_EQUALS( date.getYear(), 1493 );
      TS_ASSERT_EQUALS( date.getMonth(), 2 );
    }

  void testIncrementDay( void )
    {
      DateTime date((unsigned int) 1492,  // year
		    (unsigned int) 10,     // month
		    (unsigned int) 12,    // day 
		    (unsigned int) 12,     // hour
		    (unsigned int) 0,     // minute
		    (double) 0.0);        // second

      date.incrementDay(4);
      
      TS_ASSERT_EQUALS( date.getDay(), 16 );
    }

  void testIncrementHours( void )
    {
      DateTime date((unsigned int) 1492,  // year
		    (unsigned int) 10,     // month
		    (unsigned int) 12,    // day 
		    (unsigned int) 12,     // hour
		    (unsigned int) 0,     // minute
		    (double) 0.0);        // second

      date.incrementHours(50);
      
      TS_ASSERT_EQUALS( date.getDay(), 14 );
      TS_ASSERT_EQUALS( date.getHours(), 14 );
    }

  void testIncrementMinutes( void )
    {
      DateTime date((unsigned int) 1492,  // year
		    (unsigned int) 10,     // month
		    (unsigned int) 12,    // day 
		    (unsigned int) 12,     // hour
		    (unsigned int) 0,     // minute
		    (double) 0.0);        // second

      date.incrementMinutes(65);
      
      TS_ASSERT_EQUALS( date.getHours(), 13 );
      TS_ASSERT_EQUALS( date.getMinutes(), 5 );
    }

  void testIncrementSeconds( void )
    {
      DateTime date((unsigned int) 1492,  // year
		    (unsigned int) 10,     // month
		    (unsigned int) 12,    // day 
		    (unsigned int) 12,     // hour
		    (unsigned int) 0,     // minute
		    (double) 0.0);        // second

      TS_ASSERT_DELTA( date.getMJD(), -133704.5000, 1e-4 );
      date.incrementSeconds(65.5);
      TS_ASSERT_DELTA( date.getMJD(), -133704.4992419, 1e-4 );
      
      TS_ASSERT_EQUALS( date.getMinutes(), 1 );
      TS_ASSERT_EQUALS( date.getSeconds(), 5.5 );
    }

  void testGetDayOfYear( void )
    {
      DateTime date((unsigned int) 2007,  // year
		    (unsigned int) 3,     // month
		    (unsigned int) 1,    // day 
		    (unsigned int) 0,     // hour
		    (unsigned int) 0,     // minute
		    (double) 0.0);        // second

      TS_ASSERT_EQUALS( date.getDayOfYear(), 60);

      // Verify that it works for leap years:
      DateTime date_leap_year((unsigned int) 2008,  // year
			      (unsigned int) 3,     // month
			      (unsigned int) 1,    // day 
			      (unsigned int) 0,     // hour
			      (unsigned int) 0,     // minute
			      (double) 0.0);        // second

      TS_ASSERT_EQUALS( date_leap_year.getDayOfYear(), 61);
    }
};

#endif /*DATETIME_TEST_H_*/