#!/usr/bin/perl

#    NetUseMod is a program to moderate Usenet posts via web interface.
#    Copyright (C) 2024  Salahuddin <salahuddin@member.fsf.org>
#
#    This program is free software: you can redistribute it and/or modify
#    it under the terms of the GNU General Public License as published by
#    the Free Software Foundation, either version 3 of the License, or
#    (at your option) any later version.
#
#    This program is distributed in the hope that it will be useful,
#    but WITHOUT ANY WARRANTY; without even the implied warranty of
#    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
#    GNU General Public License for more details.
#
#    You should have received a copy of the GNU General Public License
#    along with this program.  If not, see <https://www.gnu.org/licenses/>.

use strict;
use warnings;

my $message_dir = 'YOUR_HOME_DIR/incoming_news/';
my $noreply_mail = 'no-reply@YOUR_DOMAIN';
my $send_rec_ack = 1;

sub saveIncomingMessage {
    my $dir_location       = shift;
    # $$ - The process number of the Perl running this script
    my $message_number     = time . $$;
    my $filename           = $dir_location . $message_number;
    my $incoming_message  = '';

    open(INCOMING_FILE, '>', $filename) or die $!;
    while (<>) {
	$incoming_message .= $_;
	print INCOMING_FILE;
	chop;
    }
    close(INCOMING_FILE);
    return $incoming_message;
}

sub parseFromAndSubject {
    my $message       = shift;
    my $from          = '';
    my $subject       = '';
    my @message_array = split(/\n/, $message);

    foreach(@message_array) {
	# first empty line
	if(/^$/) {
	    last;	    
	}
	if( /^From: / ) {
	    $from = $_;
	    $from=~ s/^From: //i;
	} elsif( /^Subject: / ) {
	    $subject = $_;
	    $subject =~ s/^Subject: //i;
	}
    }

    # trim                                                                                                                                                                                                        
    $from =~ s/^\s+|\s+$//g;
    $subject =~ s/^\s+|\s+$//g;
    return ($from, $subject);
}

sub sendReceiveAck {
    my ($from, $subject) = @_;
    system('echo "Submission received." | mail -s "Re: ' .  $subject . '" -r ' . $noreply_mail . ' \'' . $from . '\'');
}

# & needed to pass $_
my $incoming_message = &saveIncomingMessage($message_dir);
#print "incoming_message: \n" . $incoming_message . "\n";

if ($send_rec_ack eq 1) {
    my ($from, $subject) = parseFromAndSubject($incoming_message);
    # TODO: check return value
    sendReceiveAck($from, $subject);
}