view: implement quote folding and flesh out tests

Unfortunately, quoting is often excessive, so hide multi-line quotes
by default and provide anchored links to full messages instead.

2 files changed, 109 insertions, 9 deletions

diff --git a/lib/PublicInbox/View.pm b/lib/PublicInbox/View.pm
index 08849a92..3d3b6b5e 100644
--- a/lib/PublicInbox/View.pm
+++ b/lib/PublicInbox/View.pm
@@ -9,17 +9,17 @@ use Encode::MIME::Header;
 
 # only one public function:
 sub as_html {
-        my ($class, $mime) = @_;
+        my ($class, $mime, $full_pfx) = @_;
 
         headers_to_html_header($mime) .
-                multipart_text_as_html($mime) .
+                multipart_text_as_html($mime, $full_pfx) .
                 "</pre>\n";
 }
 
 # only private functions below.
 
 sub multipart_text_as_html {
-        my ($mime) = @_;
+        my ($mime, $full_pfx) = @_;
         my $rv = "";
         my $part_nr = 0;
 
@@ -33,15 +33,19 @@ sub multipart_text_as_html {
                         my $fn = $part->filename;
 
                         if ($part_nr > 0) {
-                                defined($fn) or $fn = "part #$part_nr";
+                                defined($fn) or $fn = "part #" . ($part_nr + 1);
                                 $rv .= add_filename_line($fn);
                         }
 
-                        # n.b. $part->body should already be decoded if text
-                        $rv .= escapeHTML($part->body);
+                        if (defined $full_pfx) {
+                                $rv .= add_text_body_short($part, $part_nr,
+                                                        $full_pfx);
+                        } else {
+                                $rv .= add_text_body_full($part, $part_nr);
+                        }
                         $rv .= "\n" unless $rv =~ /\n\z/s;
                 } else {
-                        $rv .= "-- part #$part_nr ";
+                        $rv .= "-- part #" . ($part_nr + 1) . " ";
                         $rv .= escapeHTML($part_type);
                         $rv .= " skipped\n";
                 }
@@ -60,6 +64,49 @@ sub add_filename_line {
         "$pad " . escapeHTML($fn) . " $pad\n";
 }
 
+sub add_text_body_short {
+        my ($part, $part_nr, $full_pfx) = @_;
+        my $n = 0;
+        my $s = escapeHTML($part->body);
+        $s =~ s!^((?:(?:&gt;[^\n]+)\n)+)!
+                my $cur = $1;
+                my @lines = split(/\n/, $cur);
+                if (@lines > 1) {
+                        # show a short snippet of quoted text
+                        $cur = join(' ', @lines);
+                        $cur =~ s/&gt; ?//g;
+
+                        my @sum = split(/\s+/, $cur);
+                        $cur = '';
+                        do {
+                                $cur .= shift(@sum) . ' ';
+                        } while (@sum && length($cur) < 68);
+                        $cur=~ s/ \z/ .../;
+                        "&gt; &lt;<a href=${full_pfx}#q${part_nr}_" . $n++ .
+                                ">$cur<\/a>&gt;";
+                } else {
+                        $cur;
+                }
+        !emg;
+        $s;
+}
+
+sub add_text_body_full {
+        my ($part, $part_nr) = @_;
+        my $n = 0;
+        my $s = escapeHTML($part->body);
+        $s =~ s!^((?:(?:&gt;[^\n]+)\n)+)!
+                my $cur = $1;
+                my @lines = split(/\n/, $cur);
+                if (@lines > 1) {
+                        "<a name=q${part_nr}_" . $n++ . ">$cur</a>";
+                } else {
+                        $cur;
+                }
+        !emg;
+        $s;
+}
+
 sub trim_message_id {
         my ($mid) = @_;
         $mid =~ tr/<>//d;
diff --git a/t/view.t b/t/view.t
index df79bd49..fbdbd884 100644
--- a/t/view.t
+++ b/t/view.t
@@ -8,6 +8,17 @@ use PublicInbox::View;
 
 # plain text
 {
+        my $body = <<EOF;
+So and so wrote:
+> keep this inline
+
+OK
+
+> Long and wordy reply goes here and it is split across multiple lines.
+> We generate links to a separate full page where quoted-text is inline.
+
+hello world
+EOF
         my $s = Email::Simple->create(
                 header => [
                         From => 'a@example.com',
@@ -16,7 +27,7 @@ use PublicInbox::View;
                         'Message-ID' => '<hello@example.com>',
                         Subject => 'this is a subject',
                 ],
-                body => "hello world\n",
+                body => $body,
         );
         $s = Email::MIME->new($s->as_string);
         my $html = PublicInbox::View->as_html($s);
@@ -24,6 +35,18 @@ use PublicInbox::View;
         # ghetto
         like($html, qr/<a href="?hello%40/s, "MID link present");
         like($html, qr/hello world\b/, "body present");
+        like($html, qr/&gt; keep this inline/, "short quoted text is inline");
+        like($html, qr/<a name=[^>]+>&gt; Long and wordy/,
+                "long quoted text is anchored");
+
+        # short page
+        my $pfx = "http://example.com/test/full";
+        my $short = PublicInbox::View->as_html($s, $pfx);
+        like($short, qr/\n&gt; keep this inline/,
+                "short quoted text is inline");
+        like($short, qr/<a href=\Q$pfx\E#[^>]+>Long and wordy/,
+                "long quoted text is made into a link");
+        ok(length($short) < length($html), "short page is shorter");
 }
 
 # multipart crap
@@ -49,7 +72,37 @@ use PublicInbox::View;
         );
 
         my $html = PublicInbox::View->as_html($mime);
-        print $html;
+        like($html, qr/hi\n-+ part #2 -+\nbye\n/, "multipart split");
+}
+
+# multipart email with attached patch
+{
+        my $parts = [
+                Email::MIME->create(
+                        attributes => { content_type => 'text/plain', },
+                        body => 'hi, see attached patch',
+                ),
+                Email::MIME->create(
+                        attributes => {
+                                content_type => 'text/plain',
+                                filename => "foo.patch",
+                        },
+                        body => "--- a/file\n+++ b/file\n" .
+                                "@@ -49, 7 +49,34 @@\n",
+                ),
+        ];
+        my $mime = Email::MIME->create(
+                header_str => [
+                        From => 'a@example.com',
+                        Subject => '[PATCH] asdf',
+                        'Message-ID' => '<patch@example.com>',
+                        ],
+                parts => $parts,
+        );
+
+        my $html = PublicInbox::View->as_html($mime);
+        like($html, qr!see attached patch\n-+ foo\.patch -+\n--- a/file\n!,
+                "parts split with filename");
 }
 
 done_testing();