$INBOX/_/text/color/ and sample user-side CSS

Since we now support more CSS classes for coloring,
give this feature more visibility.

1 files changed, 35 insertions, 0 deletions

diff --git a/lib/PublicInbox/WwwText.pm b/lib/PublicInbox/WwwText.pm
index b5874cf6..d3413ad7 100644
--- a/lib/PublicInbox/WwwText.pm
+++ b/lib/PublicInbox/WwwText.pm
@@ -88,9 +88,44 @@ sub _srch_prefix ($$) {
         1;
 }
 
+sub _colors_help ($$) {
+        my ($ctx, $txt) = @_;
+        my $ibx = $ctx->{-inbox};
+        my $base_url = $ibx->base_url($ctx->{env});
+        $$txt .= "color customization for $base_url\n";
+        $$txt .= <<EOF;
+
+public-inbox provides a stable set of CSS classes for users to
+customize colors for highlighting diffs and code.
+
+Users of browsers such as dillo, Firefox, or some browser
+extensions may start by downloading the following sample CSS file
+to control the colors they see:
+
+        ${base_url}userContent.css
+
+CSS classes
+-----------
+
+           span.q - quoted text in email messages
+
+For diff highlighting, we try to match class names with those
+used by cgit: https://git.zx2c4.com/cgit/
+
+         span.add - diff post-image lines
+
+         span.del - diff pre-image lines
+
+        span.head - diff header (metainformation)
+
+        span.hunk - diff hunk-header
+
+EOF
+}
 
 sub _default_text ($$$) {
         my ($ctx, $key, $txt) = @_;
+        return _colors_help($ctx, $txt) if $key eq 'color';
         return if $key ne 'help'; # TODO more keys?
 
         my $ibx = $ctx->{-inbox};