#! /usr1/local/bin/perl5 
$version ="1.10";
$date  ="2001-06-25";
$author = "kaa";

# This script checks the observation date of the input event file, finds
# the correct gain correction file, then runs acis_process_events. If a
# third argument is given it is used as a gain file and overrides any
# other choices.


# Get and parse the command line option 
    if ($ARGV[0]=~/-(\S+)/){
	$option=$1;
	if($option=~/h/){$help =1;}
	shift(@ARGV);
    }

if($help){
    print "\n acisgaincorr version $version $date $author\n\n";
    print "usage: acisgaincorr [-h] input_event_file output_event_file gain_file\n\n";
    print "This script checks the observation date of the input event file,\n";
    print "uses that to find the correct gain file, then corrects the gain\n";
    print "and writes to the output event file. This requires CIAO to be\n";
    print "set up and runs the tool acis_process_events. If a third argument\n";
    print "is given this is taken as the name of a gain file. In this case\n";
    print "gain correction is always performed.\n\n";
    exit(0);
}

# Check that CIAO is really set up

if($ENV{'ASCDS_BIN'} !~/\S/) 
{
    print "\n You need to set up CIAO to use this script.\n\n";
    exit(0);
}

# and we also need HEASOFT...

if($ENV{'LHEASOFT'} !~/\S/) 
{
    print "\n You need to set up HEASOFT to use this script.\n\n";
    exit(0);
}

# Check that the user gave the correct number of arguments.

if(@ARGV != 2 && @ARGV != 3)
{
    print "\n usage : acisgaincorr [-h] input_event_file output_event_file gain_file\n";
    print " type acisgaincorr -h to get more information\n\n";
    exit(0);
}

$infile  = $ARGV[0];
$outfile = $ARGV[1];
if(@ARGV == 3) {
    $gainfile = $ARGV[2];
} else {
    $gainfile = 'none';
}

# If the gainfile has not been input then find out what it should be and
# whether gain correction is required.

if ($gainfile eq 'none') {

# First read the DATE-OBS keyword from the input file to find the observation
# date

   $command = "fkeypar $infile DATE-OBS\n";
   system($command);
   $obsdate = `pget fkeypar value`;
   $year  = substr($obsdate,1,4);
   $month = substr($obsdate,6,2);
   $day   = substr($obsdate,9,2);

   print "\n","Observation performed on ",$month,"/",$day,"/",$year,"\n";

# The following somewhat messy code decides which gain file to use.

   if($year > 2000) {

     print "Detector temperature is -120 C\n";
     $gainfile = 'acisD2000-08-12gainN0003.fits';

   } elsif($year == 2000) {

     if( ($month == 1 && $day > 29) || $month < 7 || ($month == 7 && $day < 4) ) {
        print "Detector temperature is -120 C\n";
        $gainfile = 'acisD2000-01-29gainN0003.fits';
     } elsif ( ($month == 7 && $day >= 4) && ($month == 7 && $dat < 6) ) {
        print "Detector temperature is -120 C\n";
        $gainfile = 'acisD2000-07-04gainN0003.fits';
     } elsif ( ($month == 7 && $day >= 6) || ($month == 8 && $dat < 12) ) {
        print "Detector temperature is -120 C\n";
        $gainfile = 'acisD2000-07-06gainN0003.fits';
     } elsif ( ($month == 8 && $day >= 12) || $month > 8 ) {
        print "Detector temperature is -120 C\n";
        $gainfile = 'acisD2000-08-12gainN0003.fits';
     } else {
        print "Detector temperature is -110 C\n";
        $gainfile = 'acisD1999-09-16gainN0004.fits';
     }

   } elsif($year == 1999) {

     if ( ($month == 9 && $day > 16) || $month > 10 ) {
        print "Detector temperature is -110 C\n";
        $gainfile = 'acisD1999-09-16gainN0004.fits';
     } elsif ( ($month == 8 && $day > 23) || ($month == 9 && $day <= 16) ) {
        print "Detector temperature is -100 C and CTI is changing rapidly\n";
        $gainfile = 'acisD1999-08-13gainN0002.fits';
     } elsif ( $month == 8 && $day > 11 && $day <= 23 ) {
        print "Detector temperature is -100 C\n";
        $gainfile = 'acisD1999-08-13gainN0002.fits';
     } else {
        print "Detector temperature is -90 C\n";
        $gainfile = 'acisD1999-07-22gainN0002.fits';
     }

   }     

# Read the event extension to find the gain file actually used in processing

   $command = "fkeypar $infile GAINFILE\n";
   system($command);
   $gainfile_used = `pget fkeypar value`;
   $gainfile_used =~ tr/'\n//d;

   if ( substr($gainfile_used,length($gainfile_used)-length($gainfile)) eq $gainfile ) {
       print "Gain file used in processing is current - correction not required\n";
      exit(0);

   } else {

       print "Gain file used in processing was ", $gainfile_used,"\n";
       print "Correcting to use ", $gainfile, "\n";

   }

# Get the location of the Chandra data and put together the full path for
# the gain file. At the moment this is hardwired to the CALDB area but should
# really use quzcif to find the correct directory.

   $caldir = $ENV{'CALDB'} . "/data/chandra/acis/bcf/gain/";
   $gainfile = $caldir . $gainfile;

}

# Now find out what mode the data were acquired in so we can set the eventdef
# correctly.

$command = "fkeypar $infile READMODE\n";
system($command);
$readmode = `pget fkeypar value`;
$readmode =~ tr/a-z/A-Z/;
$readmode =~ tr/ '\n//d;
$command = "fkeypar $infile DATAMODE\n";
system($command);
$datamode = `pget fkeypar value`;
$datamode =~ tr/a-z/A-Z/;
$datamode =~ tr/ '\n//d;

if ( $readmode eq "TIMED" ) {

    if ( $datamode eq "FAINT" || $datamode eq "VFAINT" ) {

       $eventdef = "{d:time,s:ccd_id,s:node_id,i:expno,s:chip,s:tdet,d:det,d:sky,s:phas,l:pha,f:energy,l:pi,s:fltgrade,s:grade,x:status}";

    } elsif ( $datamode eq "GRADED" ) {

       $eventdef = "{d:time,s:ccd_id,s:node_id,i:expno,s:chip,s:tdet,d:det,d:sky,s:corn_pha,l:pha,f:energy,l:pi,s:fltgrade,s:grade,x:status}";

    } else {

       print $datamode," is not a recognized value of TIMED DATAMODE\n";
       exit(0);

    }

} elsif ( $readmode eq "CONTINUOUS" ) {

    if ( $datamode eq "3X3" ) {

	$eventdef = "{d:time,s:ccd_id,s:node_id,i:expno,s:chip,s:tdet,d:det,d:sky,s:phas,l:pha,f:energy,l:pi,s:fltgrade,s:grade, x:status}";

    } elsif ( $datamode eq "33GRADED" ) {

	$eventdef = "{d:time,s:ccd_id,s:node_id,i:expno,s:chip,s:tdet,d:det,d:sky,l:pha,f:energy,l:pi,s:fltgrade,s:grade,x:status}";

    } else {

       print $datamode," is not a recognized value of CONTINUOUS DATAMODE\n";
       exit(0);

    }

} else {

    print $readmode," is not a recognized value of READMODE\n";
    exit(0);

}

# Now put together the acis_process_events command.

$command = "acis_process_events gainfile=$gainfile eventdef=\"$eventdef\" doevtgrade=no stop=none infile=$infile outfile=$outfile acaofffile = NONE alignmentfile = NONE verbose=0";

# and run it...

print "\n",$command,"\n";
system($command);