#!/usr/bin/perl
use strict;
use warnings;

#
# Makes and applies GTI file to RGS event files.
#
# Requirements:
#    0) must be in same directory as input event files. 
#    1) text file which lists the events files to process, one per line
#    For instance, to remove the section between 1.55e8 and 1.57e8 seconds: 
#         1.55e8 1.57e8 -
#    
#    To include the section between 1.64e8 and 1.68e8 seconds: 
#         1.64e8 1.68e8 + 
#

my $currDir;
chomp ($currDir = `pwd`);

my $r1_evt1 = "r1_evt1.fits";
my $r2_evt1 = "r2_evt1.fits";
my $unittype = 'N';
my $count = 0;
my $currLine;
my @numbers;
my $num;
my @files;
my $file;
my $r1_evt ;
my $r2_evt ;
my $inst;

my $process_r1 = 0;
my $process_r2 = 0;

# Set the environment variables.


my @res1;
my $baseDir;

if ($currDir =~ m/proc/) {
   @res1 = split(/proc/, $currDir);
   $baseDir = $res1[0];
}

if (-d $baseDir."ODF") {
   $ENV{SAS_ODFPATH} = $baseDir."ODF";
   my $sumsas = glob ($baseDir."ODF/*SUM.SAS");
   $ENV{SAS_ODF} = $sumsas;
   $ENV{SAS_CCF} = $baseDir."ODF/ccf.cif";
}
if (-d $baseDir."odf") {
   $ENV{SAS_ODFPATH} = $baseDir."odf";
   my $sumsas = glob ($baseDir."odf/*SUM.SAS");
   $ENV{SAS_ODF} = $sumsas;
   $ENV{SAS_CCF} = $baseDir."odf/ccf.cif";
}


#
# I assume SAS has been initialized. Continue merrily on.
#

print "Enter the name of the file with the times to be kept or removed. \n "; 
chomp (my $times_file= <> ) ;
$times_file = $currDir."/".$times_file;

print "What spectrum binning should I use? \n"; 
print "1 = lambda (default; use this if you want to combine the same orders from different RGSes.) \n"; 
print "2 = beta \n" ;
chomp (my $combine_test = <> );

if (($combine_test ne 1) and ($combine_test ne 2)) {
   print "Not expecting that! Stopping. \n ";
   exit;
}

my $spectrumbinning;

if ($combine_test eq 1) { 
   $spectrumbinning = 'lambda'; 
}
else {
   $spectrumbinning = 'beta'; 
}

my $counttimes = 0;
my $countlines = 0;
my @starttime;
my @endtime;
my $j=0;
my $filtset;

if (-e $times_file) {
   open(TIMES, "<", $times_file);
   while ($currLine = <TIMES>) {
   $countlines ++;
   @numbers = split (/\s/, $currLine);
   # count array elements to confirm the correct format and assign to variables
   if (@numbers != 3) {
      print "The input file does not have the correct format. \n";
      exit;
      }
   }
   close(TIMES);
} 
else {
   print "Can't find the times file! \n";
   exit;
}
if (! $countlines) {
   print "Times files is empty.\n";
   exit;
}

#
#   Make the GTI files and apply the GTI files.
#      

`gtibuild file=$times_file table=gti.fits`;

print "Processing... Please wait, this will take a while.\n ";

`rgsproc orders='1 2' auxgtitables=gti.fits bkgcorrect=no withmlambdacolumn=yes entrystage=3:filter finalstage=5:fluxing spectrumbinning=$spectrumbinning`; 

print "Done. \n";