feat: add comments

internal/service/notification_service.go

@@ -35,6 +35,8 @@ const (
 	NotifFollowAccepted = "follow_accepted"
 	NotifPostLike       = "post_like"
 	NotifPostMention    = "post_mention"
+	NotifPostComment    = "post_comment"
+	NotifCommentReply   = "comment_reply"
 
 	// Reminder kinds are delivered live (email + push + a websocket toast)
 	// but NOT persisted — they're ephemeral nudges, not history.
@@ -48,7 +50,7 @@ const (
 // opt-outs map exactly), but the UI reads/writes whole categories.
 var PrefCategories = map[string][]string{
 	"follows":           {NotifFollowRequest, NotifFollowAccepted},
-	"post_interactions": {NotifPostLike, NotifPostMention},
+	"post_interactions": {NotifPostLike, NotifPostMention, NotifPostComment, NotifCommentReply},
 	"sadhna_reminders":  {NotifChantReminder, NotifQuoteReminder, NotifChantIncomplete},
 }
 
@@ -351,6 +353,59 @@ func (s *NotificationService) NotifyPostMention(ctx context.Context, mentionedID
 	})
 }
 
+// NotifyPostComment tells the post author that `commenterID` commented on
+// their post. NotifyCommentReply tells `recipientID` (the author of the
+// comment being replied to) that `replierID` replied. Both: persisted row +
+// realtime + Web Push, no email (comments are interactive, not digest-worthy).
+// Self-actions are skipped.
+func (s *NotificationService) NotifyPostComment(ctx context.Context, postID, authorID, commenterID string) {
+	s.notifyComment(ctx, NotifPostComment, postID, authorID, commenterID)
+}
+
+func (s *NotificationService) NotifyCommentReply(ctx context.Context, postID, recipientID, replierID string) {
+	s.notifyComment(ctx, NotifCommentReply, postID, recipientID, replierID)
+}
+
+func (s *NotificationService) notifyComment(ctx context.Context, kind, postID, recipientID, actorID string) {
+	if recipientID == "" || actorID == "" || recipientID == actorID {
+		return
+	}
+	off := s.disabledPrefs(ctx, recipientID)
+	if err := s.notifs.CreateComment(ctx, recipientID, actorID, postID, kind); err != nil {
+		s.logger.Warn("persist comment notification failed",
+			zap.String("recipient", recipientID), zap.String("kind", kind), zap.Error(err))
+	}
+	actorUser, _ := s.users.FindByID(ctx, actorID)
+	if !prefOff(off, kind, repository.ChannelInApp) {
+		s.publishRealtime(ctx, recipientID, kind, actorUser)
+	}
+
+	if s.push == nil || prefOff(off, kind, repository.ChannelPush) {
+		return
+	}
+	who := "Someone"
+	if actorUser != nil {
+		who = actorDisplay(actorUser)
+	}
+	// Tapping it opens the post (via its author's handle — the actor isn't the
+	// post owner on a reply). Falls back to the notification center.
+	url := s.frontendURL + "/notifications"
+	if h, err := s.notifs.PostAuthorHandle(ctx, postID); err == nil && h != "" {
+		url = s.frontendURL + "/u/" + h + "/posts#post-" + postID
+	}
+	title, body := "New comment", who+" commented on your post"
+	if kind == NotifCommentReply {
+		title, body = "New reply", who+" replied to your comment"
+	}
+	s.push.SendToUser(ctx, recipientID, PushPayload{
+		Title: title,
+		Body:  body,
+		URL:   url,
+		Icon:  s.iconURL(),
+		Tag:   kind + ":" + postID,
+	})
+}
+
 // likeMessage renders the aggregated like text: "X liked your post" or
 // "X and N others liked your post".
 func likeMessage(who string, count int) string {