Add switches to keep announcements off a page or off post pages

Announcements showed on every public page. Now each page has a "Show
announcements on this page" checkbox (pages.show_notices, on by default)
that covers the page and its posts, and the Design tab's Content section
has "Show announcements on post pages" (theme.post_notices, on by default)
for bloggers who want notices only on listings, not while reading a post.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01Sd8UPWrvyYCLj97JexNw3A

1 files changed, 12 insertions, 0 deletions

diff --git a/internal/web/handlers_blog.go b/internal/web/handlers_blog.go
index c26adfa..c1afedb 100644
--- a/internal/web/handlers_blog.go
+++ b/internal/web/handlers_blog.go
@@ -63,6 +63,10 @@ func (s *Server) blogView(r *http.Request) (map[string]any, error) {
 	return v, nil
 }
 
+// noNotices stands in for the placed announcements on pages that hide them
+// (typed, so the layout's index lookups still work).
+var noNotices = map[string][]store.Section{}
+
 // pageNum reads the ?p= of a paginated listing (1 when absent or silly).
 func pageNum(r *http.Request) int {
 	n, _ := strconv.Atoi(r.URL.Query().Get("p"))
@@ -109,6 +113,9 @@ func (s *Server) renderPage(w http.ResponseWriter, r *http.Request, page *store.
 	last := (total + per - 1) / per
 	fillExcerpts(v["theme"].(Theme), posts)
 	v["page"], v["posts"], v["pageNum"], v["lastPage"] = page, posts, n, last
+	if !page.ShowNotices {
+		v["notices"] = noNotices
+	}
 	// The pager appends ?p=N to base: no trailing slash, which /{page} would not match.
 	v["base"] = "/" + page.Slug
 	if page.IsHome {
@@ -195,6 +202,11 @@ func (s *Server) handleBlogPost(w http.ResponseWriter, r *http.Request) {
 		return
 	}
 	v["page"], v["post"] = page, post
+	// A post shows the announcements only when its page does and the theme
+	// wants them on posts at all.
+	if !page.ShowNotices || !v["theme"].(Theme).PostNotices {
+		v["notices"] = noNotices
+	}
 	s.render(w, r, "blog/post.html", v)
 }