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

# display current working directory
my $Current_Dir = getcwd; 
print STDOUT "the current directory is $Current_Dir\n";

# input files to work on
my $file_1 = "$ARGV[0]";
my $file_2 = "$ARGV[1]";
my $outfile = "outfile_$file_1";

# open files
open INFILE_1, '<', $file_1, or die "Can't open $file_1 : $!";
open INFILE_2, '<', $file_2, or die "Can't open ${file_2} : $!";
open OUTFILE, '>', $outfile, or die "Can't open $outfile : $!";

# print the title of the columns
my $titles_line = <INFILE_1>;
print OUTFILE $titles_line;

# create hash of aircraft specific data from file 2
my %aircraftID;
while (my $line_2 = <INFILE_2>){
  chomp($line_2);
  my @Elements_2 = split ';', $line_2;
  my $aircraft_id_2 = shift @Elements_2;
  $aircraftID{$aircraft_id_2} = \@Elements_2;
}
close INFILE_2;

# read each line of file1 and look for aircraft
while (my $line_1 = <INFILE_1>){
  chomp($line_1);
  my @Elements_1 = split ';', $line_1;
  my $aircraft_id_1 = $Elements_1[1];
  my $length_1 = @Elements_1;

  # monitor the process
  print STDOUT "the length is $length_1\n";  
  print STDOUT "The Table is @Elements_1\n";    
    
  # print the current line into the output file
  print OUTFILE "$line_1";

  # if the line contains an aircraft ID, search for its data in file 2
  if ($aircraft_id_1 && exists $aircraftID{$aircraft_id_1}) {
    print OUTFILE join(';',@{$aircraftID{$aircraft_id_1}}), "\n";
  } else { print OUTFILE (";" x (40-$length_1)), "\n" }
}

close INFILE_1;
close OUTFILE;
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