#!/usr/bin/perl -w empty.pl
# 	Stan Harle 
# 	stan@harle.net
#

use strict;

# Identify variables in advance (good practice!)
my ($location, $L, $el, $el2, @srtlist, @filelist, $filcheck);
my ($i, $p, $pre, $post, $strt, $ensr, $srtval, @filenames, $filenames);
my ($strt1, $ensr1);

# Input the test directory into variable $location
STARTING: 	print"Input the test directory\n";
		chomp($location = <STDIN>);

# Change directories to target directory
chdir $location || muckup();

# Read file list into directory variable @filelist
opendir (DIR, "$location");
@filelist = grep(!/^\.\.?$/, readdir (DIR));
closedir (DIR);

@srtlist =  sort  @filelist;
# Sort the values in the directory list array

# Enter starting number for search
	print"What number do you want to start from\?";
	chomp($strt = <STDIN>);
	$strt1 = $strt;

# Enter Ending number for sequence of sort
	print"What number do you want to end at\?";
	chomp($ensr = <STDIN>);
	$ensr1 = $ensr;

# Loop to fill array with 1s to block out unneeded values
	for ($p = 0; $p <= $strt; $p++) {
		$filenames[$p] = 1;
	}

# Loop to fill array with found and missing filenames
	for ($p = $strt; $p <= $ensr; $p++) {
# This prevents an uninitialized place in case of no find
		$filenames[$p] = 0;
		foreach (@srtlist) {
			if ((/$strt1/) || ( (/$p(?![0-9])/) && (substr($',0,1) !~/[0-9]/) && (substr($`,-1,1)!~/[0-9]/)) ) {
				$filenames[$p] = 1;
				$pre = $`;
				$post = $';
			}			
		}
	$strt1++;
	}

# Reinitialize $p and $i
$p=0;
$i=0;

# Print out names of missing files
	foreach (@filenames) {
		if ($_ eq 0) {
			print "$pre$p$post\n";
			$i++;		# $i is just a checker for no missing files, does nothing else
		}
		$p++;
	}


print "\nNo Missing Files\!\n" if ($i eq 0); 		# Check for no missing files

# Subroutine in case of user typos
sub muckup {
	print"$location doesn't work.\n\n Did you mistype\?\n\n";
	goto STARTING;
}