Remove useless fields from paymentDraft

At first i thought i would need to keep the second query of draftPayment
in newBookingCart, its caller, and i added these fields to pass back
the parsed or retrieved values, but when i could move that query within
draftPayment i forgot to remove them.

pkg/booking/cart.go

@@ -25,15 +25,10 @@ type cartLine struct {
 }
 
 type paymentDraft struct {
-	ArrivalDate        time.Time
-	DepartureDate      time.Time
 	NumAdults          int
 	NumTeenagers       int
 	NumChildren        int
 	NumDogs            int
-	ZonePreferences    string
-	ACSICard           bool
-	PaymentID          int
 	NumNights          int
 	Nights             string
 	Adults             string
@@ -55,24 +50,24 @@ type paymentOption struct {
 }
 
 func draftPayment(ctx context.Context, conn *database.Conn, f *bookingForm, campsiteType string) (*paymentDraft, error) {
-	var err error
 	if f.Dates == nil {
 		return nil, nil
 	}
 
-	draft := &paymentDraft{}
-	draft.ArrivalDate, err = time.Parse(database.ISODateFormat, f.Dates.ArrivalDate.Val)
-	if err != nil {
-		return nil, nil
-	}
-	draft.DepartureDate, err = time.Parse(database.ISODateFormat, f.Dates.DepartureDate.Val)
-	if err != nil {
-		return nil, nil
-	}
-
 	if f.Guests == nil {
 		return nil, nil
 	}
+
+	arrivalDate, err := time.Parse(database.ISODateFormat, f.Dates.ArrivalDate.Val)
+	if err != nil {
+		return nil, nil
+	}
+	departureDate, err := time.Parse(database.ISODateFormat, f.Dates.DepartureDate.Val)
+	if err != nil {
+		return nil, nil
+	}
+
+	draft := &paymentDraft{}
 	draft.NumAdults, err = strconv.Atoi(f.Guests.NumberAdults.Val)
 	if err != nil {
 		return nil, nil
@@ -92,12 +87,14 @@ func draftPayment(ctx context.Context, conn *database.Conn, f *bookingForm, camp
 		}
 	}
 
+	var zonePreferences string
 	if f.Options != nil && f.Options.ZonePreferences != nil {
-		draft.ZonePreferences = f.Options.ZonePreferences.Val
+		zonePreferences = f.Options.ZonePreferences.Val
 	}
 
+	var acsiCard bool
 	if f.Guests.ACSICard != nil {
-		draft.ACSICard = f.Guests.ACSICard.Checked
+		acsiCard = f.Guests.ACSICard.Checked
 	}
 
 	optionMap := make(map[int]*campsiteTypeOption)
@@ -135,20 +132,21 @@ func draftPayment(ctx context.Context, conn *database.Conn, f *bookingForm, camp
 			join currency using (currency_code)
 `,
 		database.ZeroNullUUID(f.PaymentSlug.Val),
-		draft.ArrivalDate,
+		arrivalDate,
-		draft.DepartureDate,
+		departureDate,
 		campsiteType,
 		draft.NumAdults,
 		draft.NumTeenagers,
 		draft.NumChildren,
 		draft.NumDogs,
-		draft.ZonePreferences,
+		zonePreferences,
-		draft.ACSICard,
+		acsiCard,
 		database.OptionUnitsArray(optionUnits),
 	)
+	var paymentID int
 	if err = row.Scan(
 		&f.PaymentSlug.Val,
-		&draft.PaymentID,
+		&paymentID,
 		&draft.NumNights,
 		&draft.Nights,
 		&draft.Adults,
@@ -175,7 +173,7 @@ func draftPayment(ctx context.Context, conn *database.Conn, f *bookingForm, camp
 		   join currency using (currency_code)
 		where payment_id = $1
 		order by campsite_type_option_id
-`, draft.PaymentID)
+`, paymentID)
 	if err != nil {
 		return nil, err
 	}