#!/usr/imports/bin/perl
($user, $passwd, $uid, $gid, $quota, $comment, $gcos, $home, $shell) = 
	getpwnam($ARGV[0]);
umask(0077);		# Set umask for new files
$delivered = 0;		# Message has not yet been delivered
$errno = 0;		# Delivery error
$errmsg = '';		# Delivery error message

## These are customizable variables
# The perl package that parses headers and such (this should not change)
$AUDIT_PACKAGE =	"$home/bin/audit.pl";
# The file containing the list of "friends"
$FRIENDS =		"$home/MailFriends";
# The command to print a message
$PRINT_CMD =		"/usr/local/bin/imprint -q imagen13 -n -J -h 'E-mail for Dr. Rosenfeld'";
# Directory where mail gets saved
$MAILDIR =		"$home/Mail";

if (! -e "$AUDIT_PACKAGE") {	&abort();}
require "$AUDIT_PACKAGE" ||	&abort();

# If we get this far, then the audit package has been found
&initialize();

##### Beginning of the rules (the interesting part)

#
# If the message was sent to >= 10 addresses, it qualifies as
# a mailing list message
#
if (@to + @cc >= 10)
{
	$delivered = &append_to_file("$MAILDIR/mailing-lists");
}

#
# If the message was Cc-ed to Azriel, ...
#
if (!$delivered &&
    grep(/^(cvl\.)?($user|azriel|rosenfeld)\b/i, @cc))
{
	if ($from =~ /^ar\b/)
	{
		#
		# if Azriel sent it, print it (and keep an emergency
		# backup copy).
		#
		$delivered = &printit() &&
			&append_to_file("$MAILDIR/from_ar");
	} else {
		#
		# otherwise, just save it under "cc"
		#
		$delivered = &append_to_file("$MAILDIR/cc");
	}
}

#
# If the mail was sent to a mailing list, and not to Azriel directly,
# put it in an appropriate mailbox.
#
if ( !$delivered &&
     !grep(/^(cvl\.)?($user|azriel|rosenfeld)\b/i, @to))
{
#	# Extract the mailing list name.
#	($mailinglist = $to[0]) =~ s/^([\w-]+).*/$1/;
#	if ($mailinglist =~ /^\s*$/)
#	{
#		# Paranoid case
#		$mailinglist = "Unknown";
#	}
#	$delivered = &append_to_file("$MAILDIR/lists/$mailinglist");

	$delivered = &append_to_file("$MAILDIR/mailing-lists");
}

#
# If the mail was sent from anywhere at umd.edu, print it out.
# This would be any host @.*.umd.edu, or anything without a domain.
#
if (!$delivered &&
    (($from =~ /umd\.edu$/i) || ($from =~ /^[\w-]+$/)))
{
	$delivered = &printit() &&
		&append_to_file("$MAILDIR/from_umd");
}

#
# If it's from a VIP and addressed to Azriel personally,
# print it out.
#
if (!$delivered)
{
	&read_friends("$FRIENDS");	# Put list of friends in @friends
	for (@friends)
	{
		next unless $from =~ /$_/i;

		# Yup, it comes from a friend, all right
		if (grep(/^(cvl\.)?($user|azriel|rosenfeld)\b/i, @to, @cc))
		{
			# And it's addressed to Azriel personally. Print it.

			$delivered = &printit() &&
				&append_to_file("$MAILDIR/from_friend");
		}
		last;
	}
}

#
# If none of the above, then save as unwanted mail
#
if (!$delivered)
{
	open(MAIL,">>$MAILDIR/junkmail") || do {
		$errno = $!+0;
		$errmsg = "Can't process unwanted mail: $!";
		$delivered = -1;
		&die_cleanly();
	};
	print MAIL "$header$body\n";
	close(MAIL);
}
print STDERR "$errmsg\n";
exit(0);

##### End of rules (this is where the support functions begin)

# read_friends
# This file reads the file given as argument, converts each one into
# a matchable pattern, 
sub read_friends
{
	local($fname) = @_;

	if (!open(FRIENDS, "$fname"))
	{
		# Error case: assume there are no friends :-(
		@friends = ();
		return;
	}

	while (<FRIENDS>)
	{
		s/#.*//;		# Remove comments
		chop;			# Remove trailing <CR>
		s/\./\\./g;		# Escape .s since it's a regexp
		s/\@/\\@/g;		# ...and @s
		s/\+/\\+/g;		# ...and +s
		s/\*/[^.]+/g;		# ...and replace * with [^.]+
		tr/A-Z/a-z/;		# Lowercase it all
		s/\s//g;		# Remove whitespace
		next unless /./;	# Ignore empty lines
		push(@friends,$_);
	}
}

# printit
# Make a hardcopy of the message
sub printit
{
	local(@msg);
	local($") = "\n";
	local($*) = 1;

	$= = 49;
#	open(PRINTER, ">>$home/WouldHaveBeenPrinted.log") || do {
	open(PRINTER, "|$PRINT_CMD") || do {
		$errno = $!+0;
		$errmsg = "Can't append to $home/WouldHaveBeenPrinted.log: $!";
		$delivered = -1;
		return 0;
	};

	# If the message is < 2 pages, print it out. Otherwise,
	# print only the first page.
	@msg = split(/\n/,$header.$body);
	for ($i = 0; $i <= $#msg; $i++)
	{
		if ($msg[$i] =~ /^(.{78})/)
		{
			splice(@msg,$i,1,$1,$');
		}
	}
	if ($#msg <= 2 * $=)
	{
		$" = "\n";
		print PRINTER "@msg\n\n";
	} else {
		splice(@msg,$=-1);
		print PRINTER "@msg\n[Rest of message deleted to conserve paper]\n\n";
	}
	close(PRINTER);

	return 1;
}

# append_to_file
# Append the message to a file. Returns 1 if successful, 0 otherwise.
sub append_to_file
{
	local($fname) = @_;

	open(FOLDER,">>$fname") || do {
		$errno = $!+0;
		$errmsg = "Can't append to $fname: $!";
		$delivered = -1;
		return 0;
	};
	print FOLDER "$header$body\n";
	close(FOLDER);

	return 1;
}

# abort
# This function is sort of an equivalent to 'panic()': if the
# audit stuff can't be found, it saves incoming mail to the
# user's mailbox.
#
sub abort
{
	open(MAIL, ">>/usr/spool/mail/$user") ||
	open(MAIL, ">>$home/mbox") ||
	open(MAIL, "| /usr/ucb/Mail -s 'Forwarded mail for Dr. Rosenfeld' postmaster'") ||
	die("Reality has failed. Dying");

	$/ = '';
	$_ = <>;
	print MAIL;	# Write the message header
	$/ = "\n";

	print MAIL <<_EndOfPrologue_;

***** This message could not be delivered normally. Please check
***** .forward, $0, mail and perl setups, and the general
***** structure of reality.
***** Error: $errno -- $errmsg

_EndOfPrologue_
	while(<>)
	{
		print MAIL;	# Write the message body
	}
	close(MAIL);
}

# die_cleanly
# This is very similar to abort(), but is called after the message
# has been &initialize-d.
#
sub die_cleanly
{
	open(MAIL, ">>/usr/spool/mail/$user") ||
	open(MAIL, ">>$home/mbox") ||
	open(MAIL, "| /usr/ucb/Mail -s 'Forwarded mail for Dr. Rosenfeld' postmaster'") ||
	die("Reality has failed. Dying");

	print MAIL "$header\n";	# Write the message header

	print MAIL <<_EndOfPrologue_;

***** This message could not be delivered normally. Please check
***** .forward, $0, mail and perl setups, and the general
***** structure of reality.
***** Error: $errno -- $errmsg

_EndOfPrologue_

	print MAIL "$body\n";	# Write the message body
	close(MAIL);
}