Multi options filters, fixes #231 (#262)

* OWNED environment variable for Mullvad
* CSV are now accepted for all servers filtering environment variables

internal/params/nordvpn.go

@@ -1,23 +1,37 @@
 package params
 
 import (
+	"fmt"
+	"strconv"
+
 	"github.com/qdm12/gluetun/internal/constants"
-	libparams "github.com/qdm12/golibs/params"
 )
 
-// GetNordvpnRegion obtains the region (country) for the NordVPN server from the
+// GetNordvpnRegions obtains the regions (countries) for the NordVPN server from the
 // environment variable REGION
-func (r *reader) GetNordvpnRegion() (region string, err error) {
+func (r *reader) GetNordvpnRegions() (regions []string, err error) {
 	choices := append(constants.NordvpnRegionChoices(), "")
-	return r.envParams.GetValueIfInside("REGION", choices)
+	return r.envParams.GetCSVInPossibilities("REGION", choices)
 }
 
-// GetNordvpnRegion obtains the server number (optional) for the NordVPN server from the
+// GetNordvpnRegion obtains the server numbers (optional) for the NordVPN servers from the
 // environment variable SERVER_NUMBER
-func (r *reader) GetNordvpnNumber() (number uint16, err error) {
-	n, err := r.envParams.GetEnvIntRange("SERVER_NUMBER", 0, 65535, libparams.Default("0"))
-	if err != nil {
-		return 0, err
+func (r *reader) GetNordvpnNumbers() (numbers []uint16, err error) {
+	possibilities := make([]string, 65536)
+	for i := range possibilities {
+		possibilities[i] = fmt.Sprintf("%d", i)
 	}
-	return uint16(n), nil
+	values, err := r.envParams.GetCSVInPossibilities("SERVER_NUMBER", possibilities)
+	if err != nil {
+		return nil, err
+	}
+	numbers = make([]uint16, len(values))
+	for i := range values {
+		n, err := strconv.Atoi(values[i])
+		if err != nil {
+			return nil, err
+		}
+		numbers[i] = uint16(n)
+	}
+	return numbers, nil
 }