#!/usr/bin/env perl

use strict;

use Getopt::Std;

my %opts;
my $FileToHandle;

getopts('o:', \%opts);

my $k = 0;

sub ParseEmail {

	my $FileToProcess = $_[0];
		
	my @mailBoundaries=();
	
	my $myLine = 0;
	my $recentBlank = 1;
	my $previousBlank = 1;

	# First pass to find out where to split the file...
	
	open (FILETOREAD, $FileToProcess) or die "Can't open $FileToProcess: $!\n";

	while (<FILETOREAD>) {
	
		if (/^$/) { 
			
			$recentBlank = $myLine+1;
			
			print "Recent Blank: $recentBlank\n";
		}

		if (/^From: / && $previousBlank != $recentBlank) { 
			
			push(@mailBoundaries, $previousBlank);
			$previousBlank = $recentBlank;
			print "PreviousBlank: $previousBlank\n";
		}

		if (eof && $previousBlank == 1) {
		
			push(@mailBoundaries, $previousBlank);
			push(@mailBoundaries, $myLine+1);
		
		} 
		
		elsif (eof && $previousBlank != 1) {
		
			push(@mailBoundaries, $myLine+1);
			
		}
		
		$myLine+=1;
		print "My Line: $myLine\n";
	}

	close (FILETOREAD);

	# Second pass to subset the file
	
	my $i = 0;
	
	while ($i <= ($#mailBoundaries - 1)) {
		$k+=1;
		my $j = 0;
		
		open (FILETOREAD, $FileToProcess) or die "Can't open $FileToProcess: $!\n";
		
			while (<FILETOREAD>) {

				$j+=1;
			
				if ($j >= @mailBoundaries[$i] && $j <= @mailBoundaries[$i+1]) {
				
										my $FileNameToWrite = $opts{'o'} . "_" . sprintf("%06d", $k);

					print "Mail Boundaries:";
					print map { "$_ \n" } @mailBoundaries;
					print "\n";
					print "I am going to print lines @mailBoundaries[$i] to @mailBoundaries[$i+1] from $FileToProcess to $FileNameToWrite.\n";

					open (FILETOWRITE, ">>$FileNameToWrite") or die "Can't open $FileToProcess: $!\n";
					
					print FILETOWRITE $_;
								
				}
				
			}
		
		close (FILETOREAD);
					
	$i+=1;
	
	}
		
}

foreach $FileToHandle (map { glob } @ARGV) {
	ParseEmail($FileToHandle);
}