use Mojo::Base -base;
use Mojo::Util qw(html_attr_unescape html_unescape xml_escape);
use Scalar::Util 'weaken';
has tree => sub { ['root'] };
has 'xml';
my $ATTR_RE = qr/
([^<>=\s\/]+|\/) # Key
(?:
\s*=\s*
(?s:(["'])(.*?)\g{-2}|([^>\s]*)) # Value
)?
\s*
/x;
my $TOKEN_RE = qr/
([^<]+)? # Text
(?:
<(?:
!(?:
DOCTYPE(
\s+\w+ # Doctype
(?:(?:\s+\w+)?(?:\s+(?:"[^"]*"|'[^']*'))+)? # External ID
(?:\s+\[.+?\])? # Int Subset
\s*)
|
--(.*?)--\s* # Comment
|
\[CDATA\[(.*?)\]\] # CDATA
)
|
\?(.*?)\? # Processing Instruction
|
\s*([^<>\s]+\s*(?:(?:$ATTR_RE){0,32766})*+) # Tag
)>
|
(<) # Runaway "<"
)??
/xis;
# HTML elements that only contain raw text
my %RAW = map { $_ => 1 } qw(script style);
# HTML elements that only contain raw text and entities
my %RCDATA = map { $_ => 1 } qw(title textarea);
# HTML elements with optional end tags
my %END = (body => 'head', optgroup => 'optgroup', option => 'option');
# HTML elements that break paragraphs
map { $END{$_} = 'p' } (
qw(address article aside blockquote details div dl fieldset figcaption),
qw(figure footer form h1 h2 h3 h4 h5 h6 header hgroup hr main menu nav ol p),
qw(pre section table ul)
);
# HTML table elements with optional end tags
my %TABLE = map { $_ => 1 } qw(colgroup tbody td tfoot th thead tr);
# HTML elements with optional end tags and scoping rules
my %CLOSE
= (li => [{li => 1}, {ul => 1, ol => 1}], tr => [{tr => 1}, {table => 1}]);
$CLOSE{$_} = [\%TABLE, {table => 1}] for qw(colgroup tbody tfoot thead);
$CLOSE{$_} = [{dd => 1, dt => 1}, {dl => 1}] for qw(dd dt);
$CLOSE{$_} = [{rp => 1, rt => 1}, {ruby => 1}] for qw(rp rt);
$CLOSE{$_} = [{th => 1, td => 1}, {table => 1}] for qw(td th);
# HTML elements without end tags
my %EMPTY = map { $_ => 1 } (
qw(area base br col embed hr img input keygen link menuitem meta param),
qw(source track wbr)
);
# HTML elements categorized as phrasing content (and obsolete inline elements)
my @PHRASING = (
qw(a abbr area audio b bdi bdo br button canvas cite code data datalist),
qw(del dfn em embed i iframe img input ins kbd keygen label link map mark),
qw(math meta meter noscript object output picture progress q ruby s samp),
qw(script select slot small span strong sub sup svg template textarea time u),
qw(var video wbr)
);
my @OBSOLETE = qw(acronym applet basefont big font strike tt);
my %PHRASING = map { $_ => 1 } @OBSOLETE, @PHRASING;
# HTML elements that don't get their self-closing flag acknowledged
my %BLOCK = map { $_ => 1 } (
qw(a address applet article aside b big blockquote body button caption),
qw(center code col colgroup dd details dialog dir div dl dt em fieldset),
qw(figcaption figure font footer form frameset h1 h2 h3 h4 h5 h6 head),
qw(header hgroup html i iframe li listing main marquee menu nav nobr),
qw(noembed noframes noscript object ol optgroup option p plaintext pre rp),
qw(rt s script section select small strike strong style summary table),
qw(tbody td template textarea tfoot th thead title tr tt u ul xmp)
);
sub parse {
my ($self, $html) = (shift, "$_[0]");
my $xml = $self->xml;
my $current = my $tree = ['root'];
while ($html =~ /\G$TOKEN_RE/gcso) {
my ($text, $doctype, $comment, $cdata, $pi, $tag, $runaway)
= ($1, $2, $3, $4, $5, $6, $11);
# Text (and runaway "<")
$text .= '<' if defined $runaway;
_node($current, 'text', html_unescape $text) if defined $text;
# Tag
if (defined $tag) {
# End
if ($tag =~ /^\/\s*(\S+)/) { _end($xml ? $1 : lc $1, $xml, \$current) }
# Start
elsif ($tag =~ m!^([^\s/]+)([\s\S]*)!) {
my ($start, $attr) = ($xml ? $1 : lc $1, $2);
# Attributes
my (%attrs, $closing);
while ($attr =~ /$ATTR_RE/go) {
my ($key, $value) = ($xml ? $1 : lc $1, $3 // $4);
# Empty tag
++$closing and next if $key eq '/';
$attrs{$key} = defined $value ? html_attr_unescape $value : $value;
}
# "image" is an alias for "img"
$start = 'img' if !$xml && $start eq 'image';
_start($start, \%attrs, $xml, \$current);
# Element without end tag (self-closing)
_end($start, $xml, \$current)
if !$xml && $EMPTY{$start} || ($xml || !$BLOCK{$start}) && $closing;
# Raw text elements
next if $xml || !$RAW{$start} && !$RCDATA{$start};
next unless $html =~ m!\G(.*?)<\s*/\s*\Q$start\E\s*>!gcsi;
_node($current, 'raw', $RCDATA{$start} ? html_unescape $1 : $1);
_end($start, 0, \$current);
}
}
# DOCTYPE
elsif (defined $doctype) { _node($current, 'doctype', $doctype) }
# Comment
elsif (defined $comment) { _node($current, 'comment', $comment) }
# CDATA
elsif (defined $cdata) { _node($current, 'cdata', $cdata) }
# Processing instruction (try to detect XML)
elsif (defined $pi) {
$self->xml($xml = 1) if !exists $self->{xml} && $pi =~ /xml/i;
_node($current, 'pi', $pi);
}
}
return $self->tree($tree);
}
sub render { _render($_[0]->tree, $_[0]->xml) }
sub _end {
my ($end, $xml, $current) = @_;
# Search stack for start tag
my $next = $$current;
do {
# Ignore useless end tag
return if $next->[0] eq 'root';
# Right tag
return $$current = $next->[3] if $next->[1] eq $end;
# Phrasing content can only cross phrasing content
return if !$xml && $PHRASING{$end} && !$PHRASING{$next->[1]};
} while $next = $next->[3];
}
sub _node {
my ($current, $type, $content) = @_;
push @$current, my $new = [$type, $content, $current];
weaken $new->[2];
}
sub _render {
my ($tree, $xml) = @_;
# Text (escaped)
my $type = $tree->[0];
return xml_escape $tree->[1] if $type eq 'text';
# Raw text
return $tree->[1] if $type eq 'raw';
# DOCTYPE
return '<!DOCTYPE' . $tree->[1] . '>' if $type eq 'doctype';
# Comment
return '<!--' . $tree->[1] . '-->' if $type eq 'comment';
# CDATA
return '<![CDATA[' . $tree->[1] . ']]>' if $type eq 'cdata';
# Processing instruction
return '<?' . $tree->[1] . '?>' if $type eq 'pi';
# Root
return join '', map { _render($_, $xml) } @$tree[1 .. $#$tree]
if $type eq 'root';
# Start tag
my $tag = $tree->[1];
my $result = "<$tag";
# Attributes
for my $key (sort keys %{$tree->[2]}) {
my $value = $tree->[2]{$key};
$result .= $xml ? qq{ $key="$key"} : " $key" and next unless defined $value;
$result .= qq{ $key="} . xml_escape($value) . '"';
}
# No children
return $xml ? "$result />" : $EMPTY{$tag} ? "$result>" : "$result></$tag>"
unless $tree->[4];
# Children
no warnings 'recursion';
$result .= '>' . join '', map { _render($_, $xml) } @$tree[4 .. $#$tree];
# End tag
return "$result</$tag>";
}
sub _start {
my ($start, $attrs, $xml, $current) = @_;
# Autoclose optional HTML elements
if (!$xml && $$current->[0] ne 'root') {
if (my $end = $END{$start}) { _end($end, 0, $current) }
elsif (my $close = $CLOSE{$start}) {
my ($allowed, $scope) = @$close;
# Close allowed parent elements in scope
my $parent = $$current;
while ($parent->[0] ne 'root' && !$scope->{$parent->[1]}) {
_end($parent->[1], 0, $current) if $allowed->{$parent->[1]};
$parent = $parent->[3];
}
}
}
# New tag
push @$$current, my $new = ['tag', $start, $attrs, $$current];
weaken $new->[3];
$$current = $new;
}
1;
=encoding utf8
=head1 NAME
Mojo::DOM::HTML - HTML/XML engine
=head1 SYNOPSIS
use Mojo::DOM::HTML;
# Turn HTML into DOM tree
my $html = Mojo::DOM::HTML->new;
$html->parse('<div><p id="a">Test</p><p id="b">123</p></div>');
my $tree = $html->tree;
=head1 DESCRIPTION
L<Mojo::DOM::HTML> is the HTML/XML engine used by L<Mojo::DOM>, based on the
L<HTML Living Standard|https://html.spec.whatwg.org> and the
L<Extensible Markup Language (XML) 1.0|http://www.w3.org/TR/xml/>.
=head1 ATTRIBUTES
L<Mojo::DOM::HTML> implements the following attributes.
=head2 tree
my $tree = $html->tree;
$html = $html->tree(['root']);
Document Object Model. Note that this structure should only be used very
carefully since it is very dynamic.
=head2 xml
my $bool = $html->xml;
$html = $html->xml($bool);
Disable HTML semantics in parser and activate case-sensitivity, defaults to
auto-detection based on XML declarations.
=head1 METHODS
L<Mojo::DOM::HTML> inherits all methods from L<Mojo::Base> and implements the
following new ones.
=head2 parse
$html = $html->parse('<foo bar="baz">I ♥ Mojolicious!</foo>');
Parse HTML/XML fragment.
=head2 render
my $str = $html->render;
Render DOM to HTML/XML.
=head1 SEE ALSO
L<Mojolicious>, L<Mojolicious::Guides>, L<http://mojolicious.org>.
=cut