+# Copyright (C) 2016 all contributors <meta@public-inbox.org>
+# License: AGPL-3.0+ <https://www.gnu.org/licenses/agpl-3.0.txt>
+#
+# Atom body stream for which yields getline+close methods
+package PublicInbox::WwwAtomStream;
+use strict;
+use warnings;
+
+# FIXME: locale-independence:
+use POSIX qw(strftime);
+use Date::Parse qw(strptime);
+
+use PublicInbox::Address;
+use PublicInbox::Hval qw(ascii_html);
+use PublicInbox::MID qw/mid_clean mid2path mid_escape/;
+
+# called by PSGI server after getline:
+sub close {}
+
+sub new {
+ my ($class, $ctx, $cb) = @_;
+ $ctx->{emit_header} = 1;
+ $ctx->{feed_base_url} = $ctx->{-inbox}->base_url($ctx->{env});
+ bless { cb => $cb || *close, ctx => $ctx }, $class;
+}
+
+sub response {
+ my ($class, $ctx, $code, $cb) = @_;
+ [ $code, [ 'Content-Type', 'application/atom+xml' ],
+ $class->new($ctx, $cb) ]
+}
+
+# called once for each message by PSGI server
+sub getline {
+ my ($self) = @_;
+ if (my $middle = $self->{cb}) {
+ my $mime = $middle->();
+ return feed_entry($self, $mime) if $mime;
+ }
+ delete $self->{cb} ? '</feed>' : undef;
+}
+
+# private
+
+sub title_tag {
+ my ($title) = @_;
+ $title =~ tr/\t\n / /s; # squeeze spaces
+ # try to avoid the type attribute in title:
+ $title = ascii_html($title);
+ my $type = index($title, '&') >= 0 ? "\ntype=\"html\"" : '';
+ "<title$type>$title</title>";
+}
+
+sub atom_header {
+ my ($ctx, $title) = @_;
+ my $ibx = $ctx->{-inbox};
+ my $base_url = $ctx->{feed_base_url};
+ my $search_q = $ctx->{search_query};
+ my $self_url = $base_url;
+ my $mid = $ctx->{mid};
+ if (defined $mid) { # per-thread
+ $self_url .= mid_escape($mid).'/t.atom';
+ } elsif (defined $search_q) {
+ my $query = $search_q->{'q'};
+ $title = title_tag("$query - search results");
+ $base_url .= '?' . $search_q->qs_html(x => undef);
+ $self_url .= '?' . $search_q->qs_html;
+ } else {
+ $title = title_tag($ibx->description);
+ $self_url .= 'new.atom';
+ }
+ my $mtime = (stat($ibx->{mainrepo}))[9] || time;
+
+ qq(<?xml version="1.0" encoding="us-ascii"?>\n) .
+ qq{<feed\nxmlns="http://www.w3.org/2005/Atom">} .
+ qq{$title} .
+ qq(<link\nrel="alternate"\ntype="text/html") .
+ qq(\nhref="$base_url"/>) .
+ qq(<link\nrel="self"\nhref="$self_url"/>) .
+ qq(<id>mailto:$ibx->{-primary_address}</id>) .
+ feed_updated(gmtime($mtime));
+}
+
+# returns undef or string
+sub feed_entry {
+ my ($self, $mime) = @_;
+ my $ctx = $self->{ctx};
+ my $hdr = $mime->header_obj;
+ my $mid = mid_clean($hdr->header_raw('Message-ID'));
+
+ my $uuid = mid2path($mid);
+ $uuid =~ tr!/!!d;
+ my $h = '[a-f0-9]';
+ my (@uuid5) = ($uuid =~ m!\A($h{8})($h{4})($h{4})($h{4})($h{12})!o);
+ $uuid = 'urn:uuid:' . join('-', @uuid5);
+
+ $mid = PublicInbox::Hval->new_msgid($mid);
+ my $href = $ctx->{feed_base_url} . $mid->{href}. '/';
+
+ my $date = $hdr->header('Date');
+ my @t = eval { strptime($date) } if defined $date;
+ @t = gmtime(time) unless scalar @t;
+ my $updated = feed_updated(@t);
+
+ my $title = $hdr->header('Subject');
+ $title = '(no subject)' unless defined $title && $title ne '';
+ $title = title_tag($title);
+
+ my $from = $hdr->header('From') or return;
+ my ($email) = PublicInbox::Address::emails($from);
+ my $name = join(', ',PublicInbox::Address::names($from));
+ $name = ascii_html($name);
+ $email = ascii_html($email);
+
+ my $s = '';
+ if (delete $ctx->{emit_header}) {
+ $s .= atom_header($ctx, $title);
+ }
+ $s .= "<entry><author><name>$name</name><email>$email</email>" .
+ "</author>$title$updated" .
+ qq{<content\ntype="xhtml">} .
+ qq{<div\nxmlns="http://www.w3.org/1999/xhtml">} .
+ qq(<pre\nstyle="white-space:pre-wrap">) .
+ PublicInbox::View::multipart_text_as_html($mime, $href) .
+ '</pre>' .
+ qq!</div></content><link\nhref="$href"/>!.
+ "<id>$uuid</id></entry>";
+}
+
+sub feed_updated {
+ '<updated>' . strftime('%Y-%m-%dT%H:%M:%SZ', @_) . '</updated>';
+}
+
+1;