package Sisimai::Lhost::Gmail;
use parent 'Sisimai::Lhost';
use feature ':5.10';
use strict;
use warnings;

state $Indicators = __PACKAGE__->INDICATORS;
state $ReBackbone = qr/^[ ]*-----[ ](?:Original[ ]message|Message[ ]header[ ]follows)[ ]-----/m;
state $StartingOf = {
    'message' => ['Delivery to the following recipient'],
    'error'   => ['The error that the other server returned was:'],
};
state $MarkingsOf = { 'start' => qr/Technical details of (?:permanent|temporary) failure:/ };
state $MessagesOf = {
    'expired' => [
        'DNS Error: Could not contact DNS servers',
        'Delivery to the following recipient has been delayed',
        'The recipient server did not accept our requests to connect',
    ],
    'hostunknown' => [
        'DNS Error: Domain name not found',
        'DNS Error: DNS server returned answer with no data',
    ],
};
state $StateTable = {
    # Technical details of permanent failure:
    # Google tried to deliver your message, but it was rejected by the recipient domain.
    # We recommend contacting the other email provider for further information about the
    # cause of this error. The error that the other server returned was:
    # 500 Remote server does not support TLS (state 6).
    '6'  => { 'command' => 'MAIL', 'reason' => 'systemerror' },

    # https://www.google.td/support/forum/p/gmail/thread?tid=08a60ebf5db24f7b&hl=en
    # Technical details of permanent failure:
    # Google tried to deliver your message, but it was rejected by the recipient domain.
    # We recommend contacting the other email provider for further information about the
    # cause of this error. The error that the other server returned was:
    # 535 SMTP AUTH failed with the remote server. (state 8).
    '8'  => { 'command' => 'AUTH', 'reason' => 'systemerror' },

    # https://www.google.co.nz/support/forum/p/gmail/thread?tid=45208164dbca9d24&hl=en
    # Technical details of temporary failure:
    # Google tried to deliver your message, but it was rejected by the recipient domain.
    # We recommend contacting the other email provider for further information about the
    # cause of this error. The error that the other server returned was:
    # 454 454 TLS missing certificate: error:0200100D:system library:fopen:Permission denied (#4.3.0) (state 9).
    '9'  => { 'command' => 'AUTH', 'reason' => 'systemerror' },

    # https://www.google.com/support/forum/p/gmail/thread?tid=5cfab8c76ec88638&hl=en
    # Technical details of permanent failure:
    # Google tried to deliver your message, but it was rejected by the recipient domain.
    # We recommend contacting the other email provider for further information about the
    # cause of this error. The error that the other server returned was:
    # 500 Remote server does not support SMTP Authenticated Relay (state 12).
    '12' => { 'command' => 'AUTH', 'reason' => 'relayingdenied' },

    # Technical details of permanent failure:
    # Google tried to deliver your message, but it was rejected by the recipient domain.
    # We recommend contacting the other email provider for further information about the
    # cause of this error. The error that the other server returned was:
    # 550 550 5.7.1 <****@gmail.com>... Access denied (state 13).
    '13' => { 'command' => 'EHLO', 'reason' => 'blocked' },

    # Technical details of permanent failure:
    # Google tried to deliver your message, but it was rejected by the recipient domain.
    # We recommend contacting the other email provider for further information about the
    # cause of this error. The error that the other server returned was:
    # 550 550 5.1.1 <******@*********.**>... User Unknown (state 14).
    # 550 550 5.2.2 <*****@****.**>... Mailbox Full (state 14).
    #
    '14' => { 'command' => 'RCPT', 'reason' => 'userunknown' },

    # https://www.google.cz/support/forum/p/gmail/thread?tid=7090cbfd111a24f9&hl=en
    # Technical details of permanent failure:
    # Google tried to deliver your message, but it was rejected by the recipient domain.
    # We recommend contacting the other email provider for further information about the
    # cause of this error. The error that the other server returned was:
    # 550 550 5.7.1 SPF unauthorized mail is prohibited. (state 15).
    # 554 554 Error: no valid recipients (state 15).
    '15' => { 'command' => 'DATA', 'reason' => 'filtered' },

    # https://www.google.com/support/forum/p/Google%20Apps/thread?tid=0aac163bc9c65d8e&hl=en
    # Technical details of permanent failure:
    # Google tried to deliver your message, but it was rejected by the recipient domain.
    # We recommend contacting the other email provider for further information about the
    # cause of this error. The error that the other server returned was:
    # 550 550 <****@***.**> No such user here (state 17).
    # 550 550 #5.1.0 Address rejected ***@***.*** (state 17).
    '17' => { 'command' => 'DATA', 'reason' => 'filtered' },

    # Technical details of permanent failure:
    # Google tried to deliver your message, but it was rejected by the recipient domain.
    # We recommend contacting the other email provider for further information about the
    # cause of this error. The error that the other server returned was:
    # 550 550 Unknown user *****@***.**.*** (state 18).
    '18' => { 'command' => 'DATA', 'reason' => 'filtered' },
};

sub description { 'Gmail: https://mail.google.com' }
sub make {
    # Detect an error from Gmail
    # @param    [Hash] mhead    Message headers of a bounce email
    # @param    [String] mbody  Message body of a bounce email
    # @return   [Hash]          Bounce data list and message/rfc822 part
    # @return   [Undef]         failed to parse or the arguments are missing
    # @since v4.0.0
    my $class = shift;
    my $mhead = shift // return undef;
    my $mbody = shift // return undef;

    # Google Mail
    # From: Mail Delivery Subsystem <mailer-daemon@googlemail.com>
    # Received: from vw-in-f109.1e100.net [74.125.113.109] by ...
    #
    # * Check the body part
    #   This is an automatically generated Delivery Status Notification
    #   Delivery to the following recipient failed permanently:
    #
    #        recipient-address-here@example.jp
    #
    #   Technical details of permanent failure:
    #   Google tried to deliver your message, but it was rejected by the
    #   recipient domain. We recommend contacting the other email provider
    #   for further information about the cause of this error. The error
    #   that the other server returned was:
    #   550 550 <recipient-address-heare@example.jp>: User unknown (state 14).
    #
    #   -- OR --
    #   THIS IS A WARNING MESSAGE ONLY.
    #
    #   YOU DO NOT NEED TO RESEND YOUR MESSAGE.
    #
    #   Delivery to the following recipient has been delayed:
    #
    #        mailboxfull@example.jp
    #
    #   Message will be retried for 2 more day(s)
    #
    #   Technical details of temporary failure:
    #   Google tried to deliver your message, but it was rejected by the recipient
    #   domain. We recommend contacting the other email provider for further infor-
    #   mation about the cause of this error. The error that the other server re-
    #   turned was: 450 450 4.2.2 <mailboxfull@example.jp>... Mailbox Full (state 14).
    #
    #   -- OR --
    #
    #   Delivery to the following recipient failed permanently:
    #
    #        userunknown@example.jp
    #
    #   Technical details of permanent failure:=20
    #   Google tried to deliver your message, but it was rejected by the server for=
    #    the recipient domain example.jp by mx.example.jp. [192.0.2.59].
    #
    #   The error that the other server returned was:
    #   550 5.1.1 <userunknown@example.jp>... User Unknown
    #
    return undef unless rindex($mhead->{'from'}, '<mailer-daemon@googlemail.com>') > -1;
    return undef unless index($mhead->{'subject'}, 'Delivery Status Notification') > -1;

    my $dscontents = [__PACKAGE__->DELIVERYSTATUS];
    my $emailsteak = Sisimai::RFC5322->fillet($mbody, $ReBackbone);
    my $readcursor = 0;     # (Integer) Points the current cursor position
    my $recipients = 0;     # (Integer) The number of 'Final-Recipient' header
    my $v = undef;

    for my $e ( split("\n", $emailsteak->[0]) ) {
        # Read error messages and delivery status lines from the head of the email
        # to the previous line of the beginning of the original message.
        unless( $readcursor ) {
            # Beginning of the bounce message or message/delivery-status part
            $readcursor |= $Indicators->{'deliverystatus'} if index($e, $StartingOf->{'message'}->[0]) == 0;
        }
        next unless $readcursor & $Indicators->{'deliverystatus'};
        next unless length $e;

        # Technical details of permanent failure:=20
        # Google tried to deliver your message, but it was rejected by the recipient =
        # domain. We recommend contacting the other email provider for further inform=
        # ation about the cause of this error. The error that the other server return=
        # ed was: 554 554 5.7.0 Header error (state 18).
        #
        # -- OR --
        #
        # Technical details of permanent failure:=20
        # Google tried to deliver your message, but it was rejected by the server for=
        # the recipient domain example.jp by mx.example.jp. [192.0.2.49].
        #
        # The error that the other server returned was:
        # 550 5.1.1 <userunknown@example.jp>... User Unknown
        #
        $v = $dscontents->[-1];

        if( $e =~ /\A[ \t]+([^ ]+[@][^ ]+)\z/ ) {
            # kijitora@example.jp: 550 5.2.2 <kijitora@example>... Mailbox Full
            if( $v->{'recipient'} ) {
                # There are multiple recipient addresses in the message body.
                push @$dscontents, __PACKAGE__->DELIVERYSTATUS;
                $v = $dscontents->[-1];
            }

            my $r = Sisimai::Address->s3s4($1);
            next unless Sisimai::RFC5322->is_emailaddress($r);
            $v->{'recipient'} = $r;
            $recipients++;

        } else {
            $v->{'diagnosis'} .= $e.' ';
        }
    }
    return undef unless $recipients;

    for my $e ( @$dscontents ) {
        $e->{'diagnosis'} = Sisimai::String->sweep($e->{'diagnosis'});

        unless( $e->{'rhost'} ) {
            # Get the value of remote host
            if( $e->{'diagnosis'} =~ /[ \t]+by[ \t]+([^ ]+)[.][ \t]+\[(\d+[.]\d+[.]\d+[.]\d+)\][.]/ ) {
                # Google tried to deliver your message, but it was rejected by # the server
                # for the recipient domain example.jp by mx.example.jp. [192.0.2.153].
                my $hostname = $1;
                my $ipv4addr = $2;
                if( $hostname =~ /[-0-9a-zA-Z]+[.][a-zA-Z]+\z/ ) {
                    # Maybe valid hostname
                    $e->{'rhost'} = $hostname;
                } else {
                    # Use IP address instead
                    $e->{'rhost'} = $ipv4addr;
                }
            }
        }

        my $statecode0 = $e->{'diagnosis'} =~ /[(]state[ ](\d+)[)][.]/ ? $1 : 0;
        if( exists $StateTable->{ $statecode0 } ) {
            # (state *)
            $e->{'reason'}  = $StateTable->{ $statecode0 }->{'reason'};
            $e->{'command'} = $StateTable->{ $statecode0 }->{'command'};
        } else {
            # No state code
            SESSION: for my $r ( keys %$MessagesOf ) {
                # Verify each regular expression of session errors
                next unless grep { index($e->{'diagnosis'}, $_) > -1 } @{ $MessagesOf->{ $r } };
                $e->{'reason'} = $r;
                last;
            }
        }
        next unless $e->{'reason'};

        # Set pseudo status code and override bounce reason
        $e->{'status'} = Sisimai::SMTP::Status->find($e->{'diagnosis'}) || '';
        next unless $e->{'status'} =~ /\A[45][.][1-7][.][1-9]\z/;
        $e->{'reason'} = Sisimai::SMTP::Status->name($e->{'status'}) || '';
    }
    return { 'ds' => $dscontents, 'rfc822' => $emailsteak->[1] };
}

1;
__END__

=encoding utf-8

=head1 NAME

Sisimai::Lhost::Gmail - bounce mail parser class for C<Gmail>.

=head1 SYNOPSIS

    use Sisimai::Lhost::Gmail;

=head1 DESCRIPTION

Sisimai::Lhost::Gmail parses a bounce email which created by C<Gmail>.
Methods in the module are called from only Sisimai::Message.

=head1 CLASS METHODS

=head2 C<B<description()>>

C<description()> returns description string of this module.

    print Sisimai::Lhost::Gmail->description;

=head2 C<B<make(I<header data>, I<reference to body string>)>>

C<make()> method parses a bounced email and return results as a array reference.
See Sisimai::Message for more details.

=head1 AUTHOR

azumakuniyuki

=head1 COPYRIGHT

Copyright (C) 2014-2020 azumakuniyuki, All rights reserved.

=head1 LICENSE

This software is distributed under The BSD 2-Clause License.

=cut
