#! /usr/bin/env perl

#    Program: send_local_smtp
#    Description
#      Transport. Sends the report by e-mail through the local mail system, by
#      piping a complete message to the sendmail-compatible program (sendmail,
#      msmtp, postfix, exim, FreeBSD's sendmail or dma). No credentials are
#      needed or read; the local MTA is responsible for authentication.
#      Needs nothing beyond core Perl.
#
#      Parameters: mailTo (required), mailFrom, mailCC, mailBCC, mailSubject,
#      attachment (path of a file to attach), sendmailPath (default: searched for).
#      Recipient lists may be separated by commas, semicolons or spaces.
#
#      Returns 1 on success. Anything else is a failure:
#        2 - mailTo missing
#        3 - no sendmail program found
#        4 - could not start sendmail, or attachment unreadable
#        100 + n - sendmail exited with status n
#
#    Revision History
#      2026-10-27 Claude v1.0.0 Bug 213: new, replaces the need for sendEmail.pl

use warnings;
use strict;

our $VERSION = '1.0.0';

# helper names are prefixed because transports are all loaded into package main

sub sendLocal_clean {
   my $value = shift;
   $value = '' unless defined $value;
   $value =~ s/[\r\n]+/ /g; # a value must never be able to add a header
   return $value;
}

sub sendLocal_list {
   my $value = shift;
   return grep { length } split /[\s,;]+/, ( defined $value ? $value : '' );
}

# builds the complete message (headers, blank line, body). Bcc is deliberately
# not a header; the caller puts bcc recipients on the envelope only.
sub sendLocal_buildMessage {
   my ( $parameters, $report ) = @_;
   my @headers;
   push @headers, 'From: ' . sendLocal_clean( $$parameters{'mailFrom'} ) if $$parameters{'mailFrom'};
   push @headers, 'To: ' . join( ', ', sendLocal_list( $$parameters{'mailTo'} ) );
   push @headers, 'Cc: ' . join( ', ', sendLocal_list( $$parameters{'mailCC'} ) ) if $$parameters{'mailCC'};
   push @headers, 'Subject: ' . sendLocal_clean( $$parameters{'mailSubject'} || 'sysinfo-client report' );
   push @headers, 'Date: ' . do { my @t = gmtime; sprintf( '%s, %02d %s %04d %02d:%02d:%02d +0000',
      (qw(Sun Mon Tue Wed Thu Fri Sat))[$t[6]], $t[3], (qw(Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec))[$t[4]],
      $t[5] + 1900, $t[2], $t[1], $t[0] ) };
   push @headers, 'MIME-Version: 1.0';

   my $attachment = $$parameters{'attachment'};
   if ( $attachment ) {
      open my $in, '<:raw', $attachment or return ( undef, "cannot read attachment $attachment: $!" );
      local $/;
      my $data = <$in>;
      close $in;
      require MIME::Base64;
      ( my $name = $attachment ) =~ s{.*/}{};
      $name =~ s/[^\w.\-]/_/g;
      my $boundary = '=_sysinfo_' . time . '_' . $$;
      push @headers, qq{Content-Type: multipart/mixed; boundary="$boundary"};
      my $body = "--$boundary\nContent-Type: text/plain; charset=UTF-8\nContent-Transfer-Encoding: 8bit\n\n$report\n"
         . "--$boundary\nContent-Type: application/octet-stream; name=\"$name\"\n"
         . "Content-Transfer-Encoding: base64\nContent-Disposition: attachment; filename=\"$name\"\n\n"
         . MIME::Base64::encode_base64( $data ) . "--$boundary--\n";
      return ( join( "\n", @headers ) . "\n\n" . $body, '' );
   }
   push @headers, 'Content-Type: text/plain; charset=UTF-8', 'Content-Transfer-Encoding: 8bit';
   return ( join( "\n", @headers ) . "\n\n" . $report, '' );
}

sub sendLocal_findSendmail {
   my $parameters = shift;
   return $$parameters{'sendmailPath'} if $$parameters{'sendmailPath'};
   foreach my $path ( qw( /usr/sbin/sendmail /usr/lib/sendmail /usr/local/sbin/sendmail /usr/bin/sendmail /usr/local/bin/sendmail ) ) {
      return $path if -x $path;
   }
   return;
}

sub doit {
   my ( $parameters, $report ) = @_;
   my @to = sendLocal_list( $$parameters{'mailTo'} );
   unless ( @to ) {
      print "send_local_smtp: mailTo not defined\n";
      return 2;
   }
   my $sendmail = sendLocal_findSendmail( $parameters );
   unless ( $sendmail && -x $sendmail ) {
      print "send_local_smtp: no sendmail program found\n";
      return 3;
   }
   my ( $message, $error ) = sendLocal_buildMessage( $parameters, $report );
   unless ( defined $message ) {
      print "send_local_smtp: $error\n";
      return 4;
   }
   my @recipients = ( @to, sendLocal_list( $$parameters{'mailCC'} ), sendLocal_list( $$parameters{'mailBCC'} ) );
   my @command = ( $sendmail, '-i' );
   push @command, '-f', sendLocal_clean( $$parameters{'mailFrom'} ) if $$parameters{'mailFrom'};
   push @command, '--', @recipients;
   # list form: no shell, so no quoting problems or injection
   open my $pipe, '|-', @command or do {
      print "send_local_smtp: could not start $sendmail: $!\n";
      return 4;
   };
   binmode $pipe; # message is already UTF-8 bytes
   print {$pipe} $message;
   return 1 if close $pipe;
   my $status = $? >> 8;
   print "send_local_smtp: $sendmail exited with status $status\n";
   return 100 + $status; # never 1, which would read as success
}

1;