# Copyrights 2001-2022 by [Mark Overmeer <markov@cpan.org>].
#  For other contributors see ChangeLog.
# See the manual pages for details on the licensing terms.
# Pod stripped from pm file by OODoc 2.03.
# This code is part of distribution Mail-Message.  Meta-POD processed with
# OODoc into POD and HTML manual-pages.  See README.md
# Copyright Mark Overmeer.  Licensed under the same terms as Perl itself.

package Mail::Message::Field::Full;
use vars '$VERSION';
$VERSION = '3.012';

use base 'Mail::Message::Field';

use strict;
use warnings;
use utf8;

use Encode ();
use MIME::QuotedPrint ();
use Storable 'dclone';

use Mail::Message::Field::Addresses;
use Mail::Message::Field::AuthResults;
#use Mail::Message::Field::AuthRecChain;
use Mail::Message::Field::Date;
use Mail::Message::Field::DKIM;
use Mail::Message::Field::Structured;
use Mail::Message::Field::Unstructured;
use Mail::Message::Field::URIs;

my $atext = q[a-zA-Z0-9!#\$%&'*+\-\/=?^_`{|}~];  # from RFC
my $atext_ill = q/\[\]/;     # illegal, but still used (esp spam)


use overload '""' => sub { shift->decodedBody };

#------------------------------------------


my %implementation;

BEGIN {
   $implementation{$_} = 'Addresses'
      for qw/from to sender cc bcc reply-to envelope-to
         resent-from resent-to resent-cc resent-bcc resent-reply-to
         resent-sender
         x-beenthere errors-to mail-follow-up x-loop delivered-to
         original-sender x-original-sender/;
   $implementation{$_} = 'URIs'
      for qw/list-help list-post list-subscribe list-unsubscribe
         list-archive list-owner/;
   $implementation{$_} = 'Structured'
      for qw/content-disposition content-type content-id/;
   $implementation{$_} = 'Date'
      for qw/date resent-date/;
   $implementation{$_} = 'AuthResults'
      for qw/authentication-results/;
   $implementation{$_} = 'DKIM'
      for qw/dkim-signature/;
#  $implementation{$_} = 'AuthRecChain'
#     for qw/arc-authentication-results arc-message-signature arc-seal/;
}

sub new($;$$@)
{   my $class  = shift;
    my $name   = shift;
    my $body   = @_ % 2 ? shift : undef;
    my %args   = @_;

    $body      = delete $args{body} if defined $args{body};
    unless(defined $body)
    {   (my $n, $body) = split /\s*\:\s*/s, $name, 2;
        $name = $n if defined $body;
    }
   
    return $class->SUPER::new(%args, name => $name, body => $body)
        if $class ne __PACKAGE__;

    # Look for best class to suit this field
    my $myclass = 'Mail::Message::Field::'
      . ($implementation{lc $name} || 'Unstructured');

    $myclass->SUPER::new(%args, name => $name, body => $body);
}

sub init($)
{   my ($self, $args) = @_;

    $self->SUPER::init($args);
    $self->{MMFF_name} = $args->{name};
    my $body           = $args->{body};

       if(!defined $body || !length $body || ref $body) { ; } # no body yet
    elsif(index($body, "\n") >= 0)
         { $self->foldedBody($body) }        # body is already folded
    else { $self->unfoldedBody($body) }      # body must be folded

    $self;
}

sub clone() { dclone(shift) }
sub name()  { lc shift->{MMFF_name}}
sub Name()  { shift->{MMFF_name}}

sub folded()
{   my $self = shift;
    return $self->{MMFF_name}.':'.$self->foldedBody
        unless wantarray;

    my @lines = $self->foldedBody;
    my $first = $self->{MMFF_name}. ':'. shift @lines;
    ($first, @lines);
}

sub unfoldedBody($;$)
{   my ($self, $body) = (shift, shift);

    if(defined $body)
    {    $self->foldedBody(scalar $self->fold($self->{MMFF_name}, $body));
         return $body;
    }

    $body = $self->foldedBody;
    $body =~ s/^ //;

	# remove FWS, also required within quoted strings.
    $body =~ s/\r?\n\s?/ /g;
    $body =~ s/ +$//;
    $body;
}

sub foldedBody($)
{   my ($self, $body) = @_;

    if(@_==2)
    {    $self->parse($body);
         $body =~ s/^\s*/ /m;
         $self->{MMFF_body} = $body;
    }
    elsif(defined($body = $self->{MMFF_body})) { ; }
    else
    {   # Create a new folded body from the parts.
        $self->{MMFF_body} = $body
           = $self->fold($self->{MMFF_name}, $self->produceBody);
    }

    wantarray ? (split /^/, $body) : $body;
}

#------------------------------------------


sub from($@)
{   my ($class, $field) = (shift, shift);
    defined $field ?  $class->new($field->Name, $field->foldedBody, @_) : ();
}

#------------------------------------------


sub decodedBody()
{   my $self = shift;
    $self->decode($self->unfoldedBody, @_);
}

#------------------------------------------


sub createComment($@)
{   my ($thing, $comment) = (shift, shift);

    $comment = $thing->encode($comment, @_)
        if @_; # encoding required...

    # Correct dangling parenthesis
    local $_ = $comment;               # work with a copy
    s#\\[()]#xx#g;                     # remove escaped parens
    s#[^()]#x#g;                       # remove other chars
    while( s#\(([^()]*)\)#x$1x# ) {;}  # remove pairs of parens

    substr($comment, CORE::length($_), 0, '\\')
        while s#[()][^()]*$##;         # add escape before remaining parens

    $comment =~ s#\\+$##;              # backslash at end confuses
    "($comment)";
}


sub createPhrase($)
{   my $self = shift;
    local $_ = shift;

    # I do not case whether it gets a but sloppy in the header string,
    # as long as it is functionally correct: no folding inside phrase
    # quotes.
    return $_ = $self->encode($_, @_, force => 1)
        if length $_ > 50;

    $_ =  $self->encode($_, @_)
        if @_;  # encoding required...

    if( m/[^$atext]/ )
    {   s#\\#\\\\#g;
        s#"#\\"#g;
        $_ = qq["$_"];
    }

    $_;
}


sub beautify() { shift }

#------------------------------------------


sub _mime_word($$) { "$_[0]$_[1]?=" }
sub _encode_b($)   { MIME::Base64::encode_base64(shift, '')  }

sub _encode_q($)   # RFC2047 sections 4.2 and 5
{   my $chunk = shift;
    $chunk =~ s#([^a-zA-Z0-9!*+/=_ -])#sprintf "=%02X", ord $1#ge;
    $chunk =~ s#([_\?,"])#sprintf "=%02X", ord $1#ge;
    $chunk =~ s/ /_/g;     # special case for =? ?= use
    $chunk;
}

sub encode($@)
{   my ($self, $utf8, %args) = @_;

    my ($charset, $lang, $encoding);

    if($charset = $args{charset})
    {   $self->log(WARNING => "Illegal character in charset '$charset'")
            if $charset =~ m/[\x00-\ ()<>@,;:"\/[\]?.=\\]/;
    }
    else { $charset = 'us-ascii' }

    if($lang = $args{language})
    {   $self->log(WARNING => "Illegal character in language '$lang'")
            if $lang =~ m/[\x00-\ ()<>@,;:"\/[\]?.=\\]/;
    }

    if($encoding = $args{encoding})
    {   unless($encoding =~ m/^[bBqQ]$/ )
        {   $self->log(WARNING => "Illegal encoding '$encoding', used 'q'");
            $encoding = 'q';
        }
    }
    else { $encoding = 'q' }

    my $name  = $args{name};
    my $lname = defined $name ? length($name)+1 : 0;

    return $utf8
        if lc($encoding) eq 'q'
        && length $utf8 < 70
        && ($utf8 =~ m/\A[\p{IsASCII}]+\z/ms && !$args{force});

    my $pre = '=?'. $charset. ($lang ? '*'.$lang : '') .'?'.$encoding.'?';

    my @result;
    if(lc($encoding) eq 'q')
    {   my $chunk  = '';
        my $llen = 73 - length($pre) - $lname;

        while(length(my $chr = substr($utf8, 0, 1, '')))
        {   $chr  = _encode_q Encode::encode($charset, $chr, 0);
            if(bytes::length($chunk) + bytes::length($chr) > $llen)
            {   push @result, _mime_word($pre, $chunk);
                $chunk = '';
                $llen = 73 - length $pre;
            }
            $chunk .= $chr;
        }
        push @result, _mime_word($pre, $chunk)
            if length($chunk);
    }
    else
    {    my $chunk  = '';
         my $llen = int((73 - length($pre) - $lname) / 4) * 3;
         while(length(my $chr = substr($utf8, 0, 1, '')))
         {   my $chr = Encode::encode($charset, $chr, 0);
             if(bytes::length($chunk) + bytes::length($chr) > $llen)
             {   push @result, _mime_word($pre, _encode_b($chunk));
                 $chunk = '';
                 $llen  = int((73 - length $pre) / 4) * 3;
             }
             $chunk .= $chr;
        }
        push @result, _mime_word($pre, _encode_b($chunk))
            if length $chunk;
    }

    join ' ', @result;
}


sub _decoder($$$)
{   my ($charset, $encoding, $encoded) = @_;
    $charset   =~ s/\*[^*]+$//;   # language component not used
    my $to_utf8 = Encode::find_encoding($charset || 'us-ascii');
    $to_utf8 or return $encoded;

    my $decoded;
    if($encoding !~ /\S/)
    {   $decoded = $encoded;
    }
    elsif(lc($encoding) eq 'q')
    {   # Quoted-printable encoded
        $encoded =~ s/_/ /g;   # specific to mime-fields
        $decoded = MIME::QuotedPrint::decode_qp($encoded);
    }
    elsif(lc($encoding) eq 'b')
    {   # Base64 encoded
        require MIME::Base64;
        $decoded = MIME::Base64::decode_base64($encoded);
    }
    else
    {   # unknown encodings ignored
        return $encoded;
    }

    $to_utf8->decode($decoded, Encode::FB_DEFAULT);  # error-chars -> '?'
}

sub decode($@)
{   my $thing   = shift;
    my @encoded = split /(\=\?[^?\s]*\?[bqBQ]?\?[^?]*\?\=)/, shift;
    @encoded or return '';

    my %args    = @_;

    my $is_text = defined $args{is_text} ? $args{is_text} : 1;
    my @decoded = shift @encoded;

    while(@encoded)
    {   shift(@encoded) =~ /\=\?([^?\s]*)\?([^?\s]*)\?([^?]*)\?\=/;
        push @decoded, _decoder $1, $2, $3;

        @encoded or last;

        # in text, blanks between encoding must be removed, but otherwise kept
        if($is_text && $encoded[0] !~ m/\S/) { shift @encoded }
        else { push @decoded, shift @encoded }
    }

    join '', @decoded;
}

#------------------------------------------


sub parse($) { shift }


sub consumePhrase($)
{   my ($thing, $string) = @_;

    my $phrase;
    if($string =~ s/^\s*\" ((?:[^"\r\n\\]*|\\.)*) (?:\"|\s*$)//x )
    {   ($phrase = $1) =~ s/\\\"/"/g;
    }
    elsif($string =~ s/^\s*((?:\=\?.*\?\=|[${atext}${atext_ill}\ \t.])+)//o )
    {   ($phrase = $1) =~ s/\s+$//;
        CORE::length($phrase) or undef $phrase;
    }
        
      defined $phrase
    ? ($thing->decode($phrase), $string)
    : (undef, $string);
}


sub consumeComment($)
{   my ($thing, $string) = @_;

    return (undef, $string)
        unless $string =~ s/^\s*\(((?:[^)\\]+|\\.)*)\)//;

    my $comment = $1;
    while(1)
    {   (my $count = $comment) =~ s/\\./xx/g;

        last if $count =~ tr/(//  ==  $count =~ tr/)//;

        return (undef, $_[1])
            unless $string =~ s/^((?:[^)\\]+|\\.)*)\)//;

        $comment .= ')'.$1;
    }

    $comment =~ s/\\([()])/$1/g;
    ($comment, $string);
}


sub consumeDotAtom($)
{   my ($self, $string) = @_;
    my ($atom, $comment);

    while(1)
    {   (my $c, $string) = $self->consumeComment($string);
        if(defined $c) { $comment .= $c; next }

        last unless $string =~ s/^\s*([$atext]+(?:\.[$atext]+)*)//o;

        $atom .= $1;
    }

    ($atom, $string, $comment);
}


sub produceBody() { $_[0]->{MMFF_body} }

#------------------------------------------



1;