#!/usr/bin/env perl
# +-======-+ 
#  Copyright (c) 2003-2018 United States Government as represented by 
#  the Admistrator of the National Aeronautics and Space Administration.  
#  All Rights Reserved.
#  
#  THIS OPEN  SOURCE  AGREEMENT  ("AGREEMENT") DEFINES  THE  RIGHTS  OF USE,
#  REPRODUCTION,  DISTRIBUTION,  MODIFICATION AND REDISTRIBUTION OF CERTAIN 
#  COMPUTER SOFTWARE ORIGINALLY RELEASED BY THE UNITED STATES GOVERNMENT AS 
#  REPRESENTED BY THE GOVERNMENT AGENCY LISTED BELOW ("GOVERNMENT AGENCY").  
#  THE UNITED STATES GOVERNMENT, AS REPRESENTED BY GOVERNMENT AGENCY, IS AN 
#  INTENDED  THIRD-PARTY  BENEFICIARY  OF  ALL  SUBSEQUENT DISTRIBUTIONS OR 
#  REDISTRIBUTIONS  OF THE  SUBJECT  SOFTWARE.  ANYONE WHO USES, REPRODUCES, 
#  DISTRIBUTES, MODIFIES  OR REDISTRIBUTES THE SUBJECT SOFTWARE, AS DEFINED 
#  HEREIN, OR ANY PART THEREOF,  IS,  BY THAT ACTION, ACCEPTING IN FULL THE 
#  RESPONSIBILITIES AND OBLIGATIONS CONTAINED IN THIS AGREEMENT.
#  
#  Government Agency: National Aeronautics and Space Administration
#  Government Agency Original Software Designation: GSC-15354-1
#  Government Agency Original Software Title:  GEOS-5 GCM Modeling Software
#  User Registration Requested.  Please Visit http://opensource.gsfc.nasa.gov
#  Government Agency Point of Contact for Original Software:  
#  			Dale Hithon, SRA Assistant, (301) 286-2691
#  
# +-======-+ 
#--------------------------------------------------
#
# Purpose: verify that all entries in obs-sys-rc 
#          exist; flag data not found and, optionally,
#          touch to create a zero-length file.
#
# Usage:
#
#  verify_obsys.pl [options] obsys.rc
#
# !REVISION HISTORY:
#
#   18Nov2013 Todling  Initial code
#
#--------------------------------------------------
use Env;                 # make env vars readily available
use File::Basename;      # for basename(), dirname()
use File::Copy "cp";     # for cp()
use Getopt::Long;        # load module with GetOptions function
use Shell qw(cat cut wc); # shell commands
use Time::Local;         # time functions
use FindBin;             # so we can find where this script resides
use lib ( "$FindBin::Bin" );
use POSIX qw(strftime);
use Manipulate_time;

#use strict;
#use warnings;

# Main ...
#{

my($oclass,@obsclass,$obsysrc);
my(%flags);

# FVROOT is where the binaries have been installed
# ------------------------------------------------
#$fvroot  = dirname($FindBin::Bin);
#$fvroot  =~ s|/u/.realmounts/share|/share|;   # for portability across
                                              # NAS machines

# Initialize variables
# --------------------
  init();

  foreach $oclass ( @obsclass ) {
     chomp($oclass);
     process_class ($oclass);
  }

#}
#.........................................................
sub init {

   GetOptions ( "debug",
                "touch",
                "h" );

   if ( $#ARGV  <  0 || $opt_h ) {
     print STDERR " Improper input parameters ; see usage:\n";
     usage();
   } else {              # required command line args
     $obsysrc = $ARGV[0];
   }

   if ($ENV{OBSCLASS} ) {
      $obsclass = $ENV{OBSCLASS};
      @obsclass = split(/,/, $obsclass);
   } else {
      @obsclass = (`grep BEGIN $obsysrc | grep -v "#" | cut -d" " -f2`);
   }

   if($opt_touch) {
      $do_touch = 1;
   } else {
      $do_touch = 0; 
   }

}
#.........................................................
sub process_class {

my($class) = @_;

my($nc,$nlines,$first);

$nlines = `wc -l < $obsysrc`;
open my $info, $obsysrc or die "Could not open $obsysrc: $!";

$nc = 0;
while( my $line = <$info>)  {   
    $first = substr($line, 0, 1); 
    if ( $first eq "#" ) { next };
    if ($nc > 0 || $line =~ $class) {
        # at this point we are dealing with a single table
        $nc++;
        if ($line !~ "BEGIN" & $line !~ "END" ) {
           handle_entry($line);
        }
        if ($line =~ "END") {$nc = 0}; 
    }
    last if $. == $nlines;
}
close $info;

}
#.......................................
sub handle_entry{
# this handles a single line within a class of a typical obsys.rc file
    my($entry) = @_;
    my(@tokens,$beg_date,$end_date,$extra,@aux,$freq);
    my($nymdb,$hhb,$nymde,$hhe,$freq_sc,$filetmpl);
    # get begin and end times of data availability
    @tokens = split(/-/, $entry); # separate first date string
    $beg_date = $tokens[0];
    $extra    = $tokens[1];
    @tokens = split(/\s+/, $extra); # separate second date string
    $end_date = $tokens[0];
    $extra    = $tokens[1];
    $nymdb = `echo $beg_date | cut -c1-8`; chomp($nymdb);
    $hhb   = `echo $beg_date | cut -c10-11`; chomp($hhb);
    $nymde = `echo $end_date | cut -c1-8`; chomp($nymde);
    $hhe   = `echo $end_date | cut -c10-11`; chomp($hhe);
    # get frequency of data in archive
    @tokens = split(/\s+/, $extra); # separate second date string
    $freq   = $tokens[0]; chomp($freq);
    $extra  = $tokens[1];
    if ($freq eq "120000") {
        $freq_sc = 12 * 3600;
    } else {
        $freq_sc =  6 * 3600;
    }
    # get file name (remove dirac or machine location from file path)
    @tokens = split(/\s+/, $entry);
    if ($tokens[3] =~ ":" ) {
        @aux = split(/:/, $tokens[3]);
        $filetmpl = $aux[1];
    } else {
        $filetmpl = $tokens[3];
    }
    # get today's date and make sure end-date is no larger than that
    my $today_date = strftime "%Y%m%d", localtime;
    if($nymde > $today_date) {$nymde = $today_date; $hhe = sprintf "%02d", 0;};

    # verify data in archive ...
    do_verify($nymdb,$hhb,$nymde,$hhe,$freq_sc,$filetmpl);
}
#.......................................
sub do_verify{
    my($nymdb,$hhb,$nymde,$hhe,$freq_sc,$filetmpl) = @_;
    my($filename,$nymd,$nhms);

    $nymd = $nymdb;
    $nhms = "${hhb}0000";

    $done=0;
    while ( ! $done ) {
       $filename = token_resolve($filetmpl,$nymd,$nhms);
       chomp($filename);
       if (! -e "$filename" ) {
          if ( $do_touch ) {
            print "touch $filename \n";
          } else {
            print "Missing File: $filename \n";
          }
       }
       ( $nymd, $nhms ) = tick ($nymd, $nhms, $freq_sc);
       if( $nymd > $nymde ) {$done = 1};
    }
}

#.......................................
sub usage {

   print <<"EOF";

NAME
     verify_obsys.pl - check files in obsys-rc and take action if requested

SYNOPSIS

     verify_obsys.pl [options] obsys.rc

DESCRIPTION

     Given observation classes defined in OBSCLASS env variable
     verify that data in that class do exist in the archive. Prints
     out data files when not found in archive and optionally it produces
     a list of touch commands for all missing files - user paste list
     a touch files if desired.

    Optinal Arguents:

    -h      help (echoes this usage)
    -touch  produces a list of touch commands for all missing files

    Optional Env Vars:
      OBSCLASS  - set of obsclasses as defined in main ADAS, e.g.,
                  "ncep_prep_bufr,tcvitals" (default: all classes in rc file)

EOF

  exit(1);
}