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.

1 files changed, 54 insertions, 7 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;