Astro::FITS::HdrTrans::UKIRT - Base class for translation of UKIRT instruments

  use Astro::FITS::HdrTrans::UKIRT;

 $Id$

package Astro::FITS::HdrTrans::UKIRT;

use 5.006;
use warnings;
use strict;
use Carp;

# inherit from the JAC translation class.
use base qw/ Astro::FITS::HdrTrans::JAC /;

use vars qw/ $VERSION /;

$VERSION = "1.50";

# In each class we have three sets of data.
#   - constant mappings
#   - unit mappings
#   - complex mappings

# For a constant mapping, there is no FITS header, just a generic
# header that is constant.
my %CONST_MAP = (
                 COORDINATE_UNITS    => 'degrees',
                );

# Unit mapping implies that the value propogates directly
# to the output with only a keyword name change.
my %UNIT_MAP = (
                AIRMASS_END          => "AMEND",
                AIRMASS_START        => "AMSTART",
                DEC_BASE             => "DECBASE",
                DETECTOR_INDEX       => "DINDEX", # Needs subheader
                DR_GROUP             => "GRPNUM",
                EQUINOX              => "EQUINOX",
                FILTER               => "FILTER",
                INSTRUMENT           => "INSTRUME",
                NUMBER_OF_EXPOSURES  => "NEXP",
                NUMBER_OF_OFFSETS    => "NOFFSETS",
                OBJECT               => "OBJECT",
                OBSERVATION_NUMBER   => "OBSNUM",
                OBSERVATION_TYPE     => "OBSTYPE",
                PROJECT              => "PROJECT",
                STANDARD             => "STANDARD",
                WAVEPLATE_ANGLE      => "WPLANGLE",
                X_APERTURE           => "APER_X",
                X_DIM                => "DCOLUMNS",
                X_LOWER_BOUND        => "RDOUT_X1",
                X_UPPER_BOUND        => "RDOUT_X2",
                Y_APERTURE           => "APER_Y",
                Y_DIM                => "DROWS",
                Y_LOWER_BOUND        => "RDOUT_Y1",
                Y_UPPER_BOUND        => "RDOUT_Y2"
               );

# Create the translation methods.
__PACKAGE__->_generate_lookup_methods( \%CONST_MAP, \%UNIT_MAP );

sub can_translate {
  my $self = shift;
  my $FITS_headers = shift;

  if ( exists $FITS_headers->{TELESCOP} &&
       $FITS_headers->{TELESCOP} =~ /UKIRT/ &&
       exists $FITS_headers->{FILENAME} &&
       exists $FITS_headers->{RAJ2000}) {
    return 0;
  }
  return $self->SUPER::can_translate( $FITS_headers );
}

sub to_COORDINATE_TYPE {
  my $self = shift;
  my $FITS_headers = shift;
  my $return;
  if ( exists( $FITS_headers->{EQUINOX} ) ) {
    if ( $FITS_headers->{EQUINOX} =~ /1950/ ) {
      $return = "B1950";
    } elsif ( $FITS_headers->{EQUINOX} =~ /2000/ ) {
      $return = "J2000";
    }
  }
  return $return;
}

sub from_COORDINATE_TYPE {
  return ();
}

sub to_RA_BASE {
  my $self = shift;
  my $FITS_headers = shift;
  my $return;
  if ( exists($FITS_headers->{RABASE} ) ) {
    $return = $FITS_headers->{RABASE} * 15;
  }
  return $return;
}

sub from_RA_BASE {
  my $self = shift;
  my $generic_headers = shift;
  my %return_hash;
  if ( exists( $generic_headers->{RA_BASE} ) &&
       defined( $generic_headers->{RA_BASE} ) ) {
    $return_hash{'RABASE'} = $generic_headers->{RA_BASE} / 15;
  }
  return %return_hash;
}

sub to_TELESCOPE {
  return "UKIRT";
}

sub from_TELESCOPE {
  my %return_hash = ( TELESCOP => 'UKIRT' );
  return %return_hash;
}

sub _parse_date_info {
  my $self = shift;
  my ($iso, $yyyymmdd, $utdechour) = @_;

  # If we do not have an ISO string, form one.
  if ( !defined $iso ) {

    # Convert the decimal hours to hms.
    my $uthour = int( $utdechour );
    my $utminute = int( ( $utdechour - $uthour ) * 60 );
    my $utsecond = int( ( ( ( $utdechour - $uthour ) * 60 ) - $utminute ) * 60 );
    if ( !defined( $yyyymmdd ) ) {
      $yyyymmdd = 19700101;
    }
    $iso = sprintf( "%04d-%02d-%02dT%02d:%02d:%02s",
                    substr( $yyyymmdd, 0, 4 ),
                    substr( $yyyymmdd, 4, 2 ),
                    substr( $yyyymmdd, 6, 2 ),
                    $uthour, $utminute, $utsecond);
  }
  return $self->_parse_iso_date( $iso );
}

1;