feat: check staged default hours in all booking creation paths

Integrate getClosingTimeForDate into AdminReserveSlotHandler, CreateBookingHandler, AdminRescheduleBookingHandler, and AdminCreateBookingForUserHandler. Rejects bookings when the staged schedule marks a day as closed (00:00).

backend/handlers/bookings/admin_reserve.go

@@ -119,16 +119,18 @@ func AdminReserveSlotHandler(w http.ResponseWriter, r *http.Request) {
 		localStart := req.StartTime.In(londonLocation)
 		// DB uses 0=Monday..6=Sunday; Go uses 0=Sunday..6=Saturday. Convert.
 		weekday := int((localStart.Weekday() + 6) % 7)
-		var closeStr string
-		if err := db.Conn.QueryRow(r.Context(), `SELECT end_time FROM working_hours WHERE weekday = $1`, weekday).Scan(&closeStr); err != nil {
-			if errors.Is(err, pgx.ErrNoRows) {
-				http.Error(w, "Not open on this day", http.StatusBadRequest)
-				return
-			}
+
+		closeStr, err := getClosingTimeForDate(r.Context(), db.Conn, weekday, localStart)
+		if err != nil {
 			log.Printf("Failed to get hours: %v", err)
 			http.Error(w, "Could not verify hours", http.StatusInternalServerError)
 			return
 		}
+		// 00:00 means the day is closed under the staged schedule — reject outright
+		if closeStr == "00:00" || closeStr == "00:00:00" {
+			http.Error(w, "Not open on this day", http.StatusBadRequest)
+			return
+		}
 
 		localEndLondon := localStart.Add(time.Duration(svcDuration) * time.Minute).In(londonLocation)
 		if err := checkClosingHours(localEndLondon, closeStr); err != nil {

backend/handlers/bookings/bookings.go

@@ -2197,12 +2197,17 @@ func CreateBookingHandler(w http.ResponseWriter, r *http.Request) {
 	localStart := req.StartTime.In(londonLocation)
 	// DB uses 0=Monday..6=Sunday; Go uses 0=Sunday..6=Saturday. Convert.
 	weekday := int((localStart.Weekday() + 6) % 7)
-	var closeStr string
-	if err := db.Conn.QueryRow(r.Context(), `SELECT end_time FROM working_hours WHERE weekday = $1`, weekday).Scan(&closeStr); err != nil {
+
+	closeStr, err := getClosingTimeForDate(r.Context(), db.Conn, weekday, localStart)
+	if err != nil {
 		log.Printf("Failed to get hours: %v", err)
 		http.Error(w, "Could not verify hours", http.StatusInternalServerError)
 		return
 	}
+	if closeStr == "00:00" || closeStr == "00:00:00" {
+		http.Error(w, "Not open on this day", http.StatusBadRequest)
+		return
+	}
 
 	endTime := req.StartTime.Add(time.Duration(svcDuration) * time.Minute)
 	localEndLondon := localStart.Add(time.Duration(svcDuration) * time.Minute).In(londonLocation)
@@ -4287,6 +4292,11 @@ func AdminRescheduleBookingHandler(w http.ResponseWriter, r *http.Request) {
 		http.Error(w, "Cannot reschedule to a closed day", http.StatusBadRequest)
 		return
 	}
+	// Also check the day isn't closed under a staged default hours change
+	if closeStr, err := getClosingTimeForDate(r.Context(), tx, weekday, localStart); err == nil && (closeStr == "00:00" || closeStr == "00:00:00") {
+		http.Error(w, "This day will be closed under the upcoming schedule change", http.StatusBadRequest)
+		return
+	}
 	if _, evictErr := EvictPendingReleaseOverlapping(r.Context(), tx, req.StartTime, newEndTime); evictErr != nil {
 		log.Printf("Failed to evict pending_release bookings on reschedule: %v", evictErr)
 		http.Error(w, "Internal server error", http.StatusInternalServerError)

backend/handlers/bookings/manage.go

@@ -643,6 +643,14 @@ func AdminCreateBookingForUserHandler(w http.ResponseWriter, r *http.Request) {
 			http.Error(w, "Cannot book during holiday hours when the salon is closed", http.StatusConflict)
 			return
 		}
+
+		// Also check if the day is closed under a staged default hours change
+		// whose effective_date has been reached.
+		closeStr, err := getClosingTimeForDate(r.Context(), db.Conn, weekday, localStart)
+		if err == nil && (closeStr == "00:00" || closeStr == "00:00:00") {
+			http.Error(w, "Not open on this day under upcoming schedule change", http.StatusConflict)
+			return
+		}
 	}
 
 	// Check for overlapping confirmed/in_progress/completed bookings