Public rank change log: sa_rank_log, written on rank changes, listed on the Staff page

internal/web/public.go

@@ -208,6 +208,39 @@ func (s *Server) publicStaff(w http.ResponseWriter, r *http.Request) {
 	writeJSON(w, http.StatusOK, map[string]any{"groups": groups, "staffOnline": s.serverView(x, st).StaffOnline})
 }
 
+type rankChangeView struct {
+	store.RankChange
+	Old *rankView `json:"old,omitempty"`
+	New *rankView `json:"new,omitempty"`
+}
+
+// publicRankChanges is the promotions and demotions list, with each rank's label and colour.
+func (s *Server) publicRankChanges(w http.ResponseWriter, r *http.Request) {
+	lim, off, num := page(r)
+	items, total, err := s.st.RankChanges(r.Context(), lim, off)
+	if err != nil {
+		internal(w, r, err)
+		return
+	}
+	x, err := s.staffIdx(r.Context())
+	if err != nil {
+		internal(w, r, err)
+		return
+	}
+	view := func(g string) *rankView {
+		if g == "" {
+			return nil
+		}
+		rk := s.site.rank(g, x.groupIndex(g))
+		return &rankView{Name: g, Label: rk.Label, Color: rk.Color, Supporter: rk.Supporter}
+	}
+	out := make([]rankChangeView, 0, len(items))
+	for _, c := range items {
+		out = append(out, rankChangeView{RankChange: c, Old: view(c.OldRank), New: view(c.NewRank)})
+	}
+	writeJSON(w, http.StatusOK, newList(out, total, num))
+}
+
 func (s *Server) publicPlayer(w http.ResponseWriter, r *http.Request) {
 	steamid := r.PathValue("steamid")
 	if !steam.ValidID(steamid) {