#!/usr/bin/perl -w

use File::Copy;

my($input_file1) = $ARGV[0];
my($input_file2) = $ARGV[1];
my($output_file) = $ARGV[2];

if ( !defined($input_file1) || !defined($input_file2) || !defined($output_file) ) {
	print "Error: usage: mergefiles input_file1 input_file2 output_file\n";
}
else {
	# -----Backup the input files in case of error-----
	copy( $input_file1, $input_file1 . ".bak" ) or
		die "Could not backup file 1 $input_file1 to $input_file1.bak: $!\n";
	copy( $input_file2, $input_file2 . ".bak" ) or
		die "Could not backup file 2 $input_file2 to $input_file2.bak: $!\n";

	# -----Attempt to open all of the files-----
	open( INFILE1, $input_file1 ) || die( "Could not read input file 1 ($input_file1): $!" );
	open( INFILE2, $input_file2 ) || die( "Could not read input file 2 ($input_file2): $!" );
	open( OUTPUT, "> " . $output_file ) || die( "Could not open output file ($output_file): $!" );

	# -----Read input_file2 into an array so that (later) we can do a binary search-----
	@input2 = <INFILE2>;

	while (;INFILE1>) {
		my $line = $_;
		chomp($line);

		# -----A line starting with a '2' is a header and is left unchanged
		if ( $line !~ m/^2/ ) {

			foreach $line2 (@input2) {
				$date = substr( $line, 6, 6 );
				$number_dialed = substr( $line, 29, 10 );

				if ( index( $line2, $date ) != -1 and index( $line2, $number_dialed ) != -1 ) {
					$record_type = substr( $line, 5, 2 );
					$term_id = substr( $line2, 39, 1);

					# -----From File2-----
					$carrier_info = substr( $line2, 44, 5 );
					$destination_number = substr( $line2, 122, 10 );

					$connect_time = substr( $line, 54, 6 );
					$from_RAO = substr( $line, 71, 3 );
					$indicator100 = substr( $line, 99, 1 );
					$CABS_RAO = substr( $line, 109, 3 );
					$settlement = substr( $line, 148, 1 );
					$send_to_OCN = substr( $line, 186, 4 );

					$record_type = "xx";
					$from_RAO = "xxx";
					$indicator100 = "x";
					$CABS_RAO = "xxx";
					$settlement = "x";
					$send_to_OCN = "xxxx";
					
					# -----Generate the output string-----
					$output_line = substr( $line, 0, 4 ) . $record_type . $date . substr( $line, 12, 17 )
						. $number_dialed . $term_id . substr( $line, 40, 4 )
						. $carrier_info . substr( $line, 49, 5 )
						. $connect_time . substr( $line, 60, 11 )
						. $from_RAO . substr( $line, 74, 25 )
						. $indicator100 . substr( $line, 100, 9 )
						. $CABS_RAO . substr( $line, 112, 10 )
						. $destination_number . substr( $line, 132, 16 )
						. $settlement . substr( $line, 149, 37 )
						. $send_to_OCN . substr( $line, 190, 20 ) . "\n";

					print OUTPUT $output_line;

					# -----If we have found the line, we want to exit the loop-----
					last;
				}
			}
		}
		else {
			print OUTPUT $line . "\n";
		}
	}

	# -----Close all of the files-----
	close( INFILE1 );
	close( INFILE2 );
	close( OUTPUT );
}