chore(validation): uniformize server filters build

internal/configuration/settings/serverselection.go

@@ -144,82 +144,82 @@ func getLocationFilterChoices(vpnServiceProvider string, ss *ServerSelection,
 	case providers.Custom:
 	case providers.Cyberghost:
 		servers := allServers.GetCyberghost()
-		countryChoices = validation.CyberghostCountryChoices(servers)
-		hostnameChoices = validation.CyberghostHostnameChoices(servers)
+		countryChoices = validation.ExtractCountries(servers)
+		hostnameChoices = validation.ExtractHostnames(servers)
 	case providers.Expressvpn:
 		servers := allServers.GetExpressvpn()
-		countryChoices = validation.ExpressvpnCountriesChoices(servers)
-		cityChoices = validation.ExpressvpnCityChoices(servers)
-		hostnameChoices = validation.ExpressvpnHostnameChoices(servers)
+		countryChoices = validation.ExtractCountries(servers)
+		cityChoices = validation.ExtractCities(servers)
+		hostnameChoices = validation.ExtractHostnames(servers)
 	case providers.Fastestvpn:
 		servers := allServers.GetFastestvpn()
-		countryChoices = validation.FastestvpnCountriesChoices(servers)
-		hostnameChoices = validation.FastestvpnHostnameChoices(servers)
+		countryChoices = validation.ExtractCountries(servers)
+		hostnameChoices = validation.ExtractHostnames(servers)
 	case providers.HideMyAss:
 		servers := allServers.GetHideMyAss()
-		countryChoices = validation.HideMyAssCountryChoices(servers)
-		regionChoices = validation.HideMyAssRegionChoices(servers)
-		cityChoices = validation.HideMyAssCityChoices(servers)
-		hostnameChoices = validation.HideMyAssHostnameChoices(servers)
+		countryChoices = validation.ExtractCountries(servers)
+		regionChoices = validation.ExtractRegions(servers)
+		cityChoices = validation.ExtractCities(servers)
+		hostnameChoices = validation.ExtractHostnames(servers)
 	case providers.Ipvanish:
 		servers := allServers.GetIpvanish()
-		countryChoices = validation.IpvanishCountryChoices(servers)
-		cityChoices = validation.IpvanishCityChoices(servers)
-		hostnameChoices = validation.IpvanishHostnameChoices(servers)
+		countryChoices = validation.ExtractCountries(servers)
+		cityChoices = validation.ExtractCities(servers)
+		hostnameChoices = validation.ExtractHostnames(servers)
 	case providers.Ivpn:
 		servers := allServers.GetIvpn()
-		countryChoices = validation.IvpnCountryChoices(servers)
-		cityChoices = validation.IvpnCityChoices(servers)
-		ispChoices = validation.IvpnISPChoices(servers)
-		hostnameChoices = validation.IvpnHostnameChoices(servers)
+		countryChoices = validation.ExtractCountries(servers)
+		cityChoices = validation.ExtractCities(servers)
+		ispChoices = validation.ExtractISPs(servers)
+		hostnameChoices = validation.ExtractHostnames(servers)
 	case providers.Mullvad:
 		servers := allServers.GetMullvad()
-		countryChoices = validation.MullvadCountryChoices(servers)
-		cityChoices = validation.MullvadCityChoices(servers)
-		ispChoices = validation.MullvadISPChoices(servers)
-		hostnameChoices = validation.MullvadHostnameChoices(servers)
+		countryChoices = validation.ExtractCountries(servers)
+		cityChoices = validation.ExtractCities(servers)
+		ispChoices = validation.ExtractISPs(servers)
+		hostnameChoices = validation.ExtractHostnames(servers)
 	case providers.Nordvpn:
 		servers := allServers.GetNordvpn()
-		regionChoices = validation.NordvpnRegionChoices(servers)
-		hostnameChoices = validation.NordvpnHostnameChoices(servers)
+		regionChoices = validation.ExtractRegions(servers)
+		hostnameChoices = validation.ExtractHostnames(servers)
 	case providers.Perfectprivacy:
 		servers := allServers.GetPerfectprivacy()
-		cityChoices = validation.PerfectprivacyCityChoices(servers)
+		cityChoices = validation.ExtractCities(servers)
 	case providers.Privado:
 		servers := allServers.GetPrivado()
-		countryChoices = validation.PrivadoCountryChoices(servers)
-		regionChoices = validation.PrivadoRegionChoices(servers)
-		cityChoices = validation.PrivadoCityChoices(servers)
-		hostnameChoices = validation.PrivadoHostnameChoices(servers)
+		countryChoices = validation.ExtractCountries(servers)
+		regionChoices = validation.ExtractRegions(servers)
+		cityChoices = validation.ExtractCities(servers)
+		hostnameChoices = validation.ExtractHostnames(servers)
 	case providers.PrivateInternetAccess:
 		servers := allServers.GetPia()
-		regionChoices = validation.PIAGeoChoices(servers)
-		hostnameChoices = validation.PIAHostnameChoices(servers)
-		nameChoices = validation.PIANameChoices(servers)
+		regionChoices = validation.ExtractRegions(servers)
+		hostnameChoices = validation.ExtractHostnames(servers)
+		nameChoices = validation.ExtractServerNames(servers)
 	case providers.Privatevpn:
 		servers := allServers.GetPrivatevpn()
-		countryChoices = validation.PrivatevpnCountryChoices(servers)
-		cityChoices = validation.PrivatevpnCityChoices(servers)
-		hostnameChoices = validation.PrivatevpnHostnameChoices(servers)
+		countryChoices = validation.ExtractCountries(servers)
+		cityChoices = validation.ExtractCities(servers)
+		hostnameChoices = validation.ExtractHostnames(servers)
 	case providers.Protonvpn:
 		servers := allServers.GetProtonvpn()
-		countryChoices = validation.ProtonvpnCountryChoices(servers)
-		regionChoices = validation.ProtonvpnRegionChoices(servers)
-		cityChoices = validation.ProtonvpnCityChoices(servers)
-		nameChoices = validation.ProtonvpnNameChoices(servers)
-		hostnameChoices = validation.ProtonvpnHostnameChoices(servers)
+		countryChoices = validation.ExtractCountries(servers)
+		regionChoices = validation.ExtractRegions(servers)
+		cityChoices = validation.ExtractCities(servers)
+		nameChoices = validation.ExtractServerNames(servers)
+		hostnameChoices = validation.ExtractHostnames(servers)
 	case providers.Purevpn:
 		servers := allServers.GetPurevpn()
-		countryChoices = validation.PurevpnCountryChoices(servers)
-		regionChoices = validation.PurevpnRegionChoices(servers)
-		cityChoices = validation.PurevpnCityChoices(servers)
-		hostnameChoices = validation.PurevpnHostnameChoices(servers)
+		countryChoices = validation.ExtractCountries(servers)
+		regionChoices = validation.ExtractRegions(servers)
+		cityChoices = validation.ExtractCities(servers)
+		hostnameChoices = validation.ExtractHostnames(servers)
 	case providers.Surfshark:
 		servers := allServers.GetSurfshark()
-		countryChoices = validation.SurfsharkCountryChoices(servers)
-		cityChoices = validation.SurfsharkCityChoices(servers)
-		hostnameChoices = validation.SurfsharkHostnameChoices(servers)
-		regionChoices = validation.SurfsharkRegionChoices(servers)
+		countryChoices = validation.ExtractCountries(servers)
+		cityChoices = validation.ExtractCities(servers)
+		hostnameChoices = validation.ExtractHostnames(servers)
+		regionChoices = validation.ExtractRegions(servers)
 		// TODO v4 remove
 		regionChoices = append(regionChoices, validation.SurfsharkRetroLocChoices()...)
 		if err := helpers.AreAllOneOf(ss.Regions, regionChoices); err != nil {
@@ -230,26 +230,26 @@ func getLocationFilterChoices(vpnServiceProvider string, ss *ServerSelection,
 		*ss = surfsharkRetroRegion(*ss)
 	case providers.Torguard:
 		servers := allServers.GetTorguard()
-		countryChoices = validation.TorguardCountryChoices(servers)
-		cityChoices = validation.TorguardCityChoices(servers)
-		hostnameChoices = validation.TorguardHostnameChoices(servers)
+		countryChoices = validation.ExtractCountries(servers)
+		cityChoices = validation.ExtractCities(servers)
+		hostnameChoices = validation.ExtractHostnames(servers)
 	case providers.VPNUnlimited:
 		servers := allServers.GetVPNUnlimited()
-		countryChoices = validation.VPNUnlimitedCountryChoices(servers)
-		cityChoices = validation.VPNUnlimitedCityChoices(servers)
-		hostnameChoices = validation.VPNUnlimitedHostnameChoices(servers)
+		countryChoices = validation.ExtractCountries(servers)
+		cityChoices = validation.ExtractCities(servers)
+		hostnameChoices = validation.ExtractHostnames(servers)
 	case providers.Vyprvpn:
 		servers := allServers.GetVyprvpn()
-		regionChoices = validation.VyprvpnRegionChoices(servers)
+		regionChoices = validation.ExtractRegions(servers)
 	case providers.Wevpn:
 		servers := allServers.GetWevpn()
-		cityChoices = validation.WevpnCityChoices(servers)
-		hostnameChoices = validation.WevpnHostnameChoices(servers)
+		cityChoices = validation.ExtractCities(servers)
+		hostnameChoices = validation.ExtractHostnames(servers)
 	case providers.Windscribe:
 		servers := allServers.GetWindscribe()
-		regionChoices = validation.WindscribeRegionChoices(servers)
-		cityChoices = validation.WindscribeCityChoices(servers)
-		hostnameChoices = validation.WindscribeHostnameChoices(servers)
+		regionChoices = validation.ExtractRegions(servers)
+		cityChoices = validation.ExtractCities(servers)
+		hostnameChoices = validation.ExtractHostnames(servers)
 	default:
 		return nil, nil, nil, nil, nil, nil, fmt.Errorf("%w: %s", ErrVPNProviderNameNotValid, vpnServiceProvider)
 	}

internal/configuration/settings/validation/cyberghost.go

@@ -1,21 +0,0 @@
-package validation
-
-import (
-	"github.com/qdm12/gluetun/internal/models"
-)
-
-func CyberghostCountryChoices(servers []models.Server) (choices []string) {
-	choices = make([]string, len(servers))
-	for i := range servers {
-		choices[i] = servers[i].Country
-	}
-	return makeUnique(choices)
-}
-
-func CyberghostHostnameChoices(servers []models.Server) (choices []string) {
-	choices = make([]string, len(servers))
-	for i := range servers {
-		choices[i] = servers[i].Hostname
-	}
-	return makeUnique(choices)
-}

internal/configuration/settings/validation/expressvpn.go

@@ -1,29 +0,0 @@
-package validation
-
-import (
-	"github.com/qdm12/gluetun/internal/models"
-)
-
-func ExpressvpnCountriesChoices(servers []models.Server) (choices []string) {
-	choices = make([]string, len(servers))
-	for i := range servers {
-		choices[i] = servers[i].Country
-	}
-	return makeUnique(choices)
-}
-
-func ExpressvpnCityChoices(servers []models.Server) (choices []string) {
-	choices = make([]string, len(servers))
-	for i := range servers {
-		choices[i] = servers[i].City
-	}
-	return makeUnique(choices)
-}
-
-func ExpressvpnHostnameChoices(servers []models.Server) (choices []string) {
-	choices = make([]string, len(servers))
-	for i := range servers {
-		choices[i] = servers[i].Hostname
-	}
-	return makeUnique(choices)
-}

internal/configuration/settings/validation/fastestvpn.go

@@ -1,21 +0,0 @@
-package validation
-
-import (
-	"github.com/qdm12/gluetun/internal/models"
-)
-
-func FastestvpnCountriesChoices(servers []models.Server) (choices []string) {
-	choices = make([]string, len(servers))
-	for i := range servers {
-		choices[i] = servers[i].Country
-	}
-	return makeUnique(choices)
-}
-
-func FastestvpnHostnameChoices(servers []models.Server) (choices []string) {
-	choices = make([]string, len(servers))
-	for i := range servers {
-		choices[i] = servers[i].Hostname
-	}
-	return makeUnique(choices)
-}

internal/configuration/settings/validation/helpers.go

@@ -1,23 +0,0 @@
-package validation
-
-import "sort"
-
-func makeUnique(choices []string) (uniqueChoices []string) {
-	seen := make(map[string]struct{}, len(choices))
-	uniqueChoices = make([]string, 0, len(uniqueChoices))
-
-	for _, choice := range choices {
-		if _, ok := seen[choice]; ok {
-			continue
-		}
-		seen[choice] = struct{}{}
-
-		uniqueChoices = append(uniqueChoices, choice)
-	}
-
-	sort.Slice(uniqueChoices, func(i, j int) bool {
-		return uniqueChoices[i] < uniqueChoices[j]
-	})
-
-	return uniqueChoices
-}

internal/configuration/settings/validation/hidemyass.go

@@ -1,37 +0,0 @@
-package validation
-
-import (
-	"github.com/qdm12/gluetun/internal/models"
-)
-
-func HideMyAssCountryChoices(servers []models.Server) (choices []string) {
-	choices = make([]string, len(servers))
-	for i := range servers {
-		choices[i] = servers[i].Country
-	}
-	return makeUnique(choices)
-}
-
-func HideMyAssRegionChoices(servers []models.Server) (choices []string) {
-	choices = make([]string, len(servers))
-	for i := range servers {
-		choices[i] = servers[i].Region
-	}
-	return makeUnique(choices)
-}
-
-func HideMyAssCityChoices(servers []models.Server) (choices []string) {
-	choices = make([]string, len(servers))
-	for i := range servers {
-		choices[i] = servers[i].City
-	}
-	return makeUnique(choices)
-}
-
-func HideMyAssHostnameChoices(servers []models.Server) (choices []string) {
-	choices = make([]string, len(servers))
-	for i := range servers {
-		choices[i] = servers[i].Hostname
-	}
-	return makeUnique(choices)
-}

internal/configuration/settings/validation/ipvanish.go

@@ -1,29 +0,0 @@
-package validation
-
-import (
-	"github.com/qdm12/gluetun/internal/models"
-)
-
-func IpvanishCountryChoices(servers []models.Server) (choices []string) {
-	choices = make([]string, len(servers))
-	for i := range servers {
-		choices[i] = servers[i].Country
-	}
-	return makeUnique(choices)
-}
-
-func IpvanishCityChoices(servers []models.Server) (choices []string) {
-	choices = make([]string, len(servers))
-	for i := range servers {
-		choices[i] = servers[i].City
-	}
-	return makeUnique(choices)
-}
-
-func IpvanishHostnameChoices(servers []models.Server) (choices []string) {
-	choices = make([]string, len(servers))
-	for i := range servers {
-		choices[i] = servers[i].Hostname
-	}
-	return makeUnique(choices)
-}

internal/configuration/settings/validation/ivpn.go

@@ -1,37 +0,0 @@
-package validation
-
-import (
-	"github.com/qdm12/gluetun/internal/models"
-)
-
-func IvpnCountryChoices(servers []models.Server) (choices []string) {
-	choices = make([]string, len(servers))
-	for i := range servers {
-		choices[i] = servers[i].Country
-	}
-	return makeUnique(choices)
-}
-
-func IvpnCityChoices(servers []models.Server) (choices []string) {
-	choices = make([]string, len(servers))
-	for i := range servers {
-		choices[i] = servers[i].City
-	}
-	return makeUnique(choices)
-}
-
-func IvpnISPChoices(servers []models.Server) (choices []string) {
-	choices = make([]string, len(servers))
-	for i := range servers {
-		choices[i] = servers[i].ISP
-	}
-	return makeUnique(choices)
-}
-
-func IvpnHostnameChoices(servers []models.Server) (choices []string) {
-	choices = make([]string, len(servers))
-	for i := range servers {
-		choices[i] = servers[i].Hostname
-	}
-	return makeUnique(choices)
-}

internal/configuration/settings/validation/mullvad.go

@@ -1,37 +0,0 @@
-package validation
-
-import (
-	"github.com/qdm12/gluetun/internal/models"
-)
-
-func MullvadCountryChoices(servers []models.Server) (choices []string) {
-	choices = make([]string, len(servers))
-	for i := range servers {
-		choices[i] = servers[i].Country
-	}
-	return makeUnique(choices)
-}
-
-func MullvadCityChoices(servers []models.Server) (choices []string) {
-	choices = make([]string, len(servers))
-	for i := range servers {
-		choices[i] = servers[i].City
-	}
-	return makeUnique(choices)
-}
-
-func MullvadHostnameChoices(servers []models.Server) (choices []string) {
-	choices = make([]string, len(servers))
-	for i := range servers {
-		choices[i] = servers[i].Hostname
-	}
-	return makeUnique(choices)
-}
-
-func MullvadISPChoices(servers []models.Server) (choices []string) {
-	choices = make([]string, len(servers))
-	for i := range servers {
-		choices[i] = servers[i].ISP
-	}
-	return makeUnique(choices)
-}

internal/configuration/settings/validation/nordvpn.go

@@ -1,21 +0,0 @@
-package validation
-
-import (
-	"github.com/qdm12/gluetun/internal/models"
-)
-
-func NordvpnRegionChoices(servers []models.Server) (choices []string) {
-	choices = make([]string, len(servers))
-	for i := range servers {
-		choices[i] = servers[i].Region
-	}
-	return makeUnique(choices)
-}
-
-func NordvpnHostnameChoices(servers []models.Server) (choices []string) {
-	choices = make([]string, len(servers))
-	for i := range servers {
-		choices[i] = servers[i].Hostname
-	}
-	return makeUnique(choices)
-}

internal/configuration/settings/validation/perfectprivacy.go

@@ -1,13 +0,0 @@
-package validation
-
-import (
-	"github.com/qdm12/gluetun/internal/models"
-)
-
-func PerfectprivacyCityChoices(servers []models.Server) (choices []string) {
-	choices = make([]string, len(servers))
-	for i := range servers {
-		choices[i] = servers[i].City
-	}
-	return makeUnique(choices)
-}

internal/configuration/settings/validation/pia.go

@@ -1,29 +0,0 @@
-package validation
-
-import (
-	"github.com/qdm12/gluetun/internal/models"
-)
-
-func PIAGeoChoices(servers []models.Server) (choices []string) {
-	choices = make([]string, len(servers))
-	for i := range servers {
-		choices[i] = servers[i].Region
-	}
-	return makeUnique(choices)
-}
-
-func PIAHostnameChoices(servers []models.Server) (choices []string) {
-	choices = make([]string, len(servers))
-	for i := range servers {
-		choices[i] = servers[i].Hostname
-	}
-	return makeUnique(choices)
-}
-
-func PIANameChoices(servers []models.Server) (choices []string) { // TODO remove in v4
-	choices = make([]string, len(servers))
-	for i := range servers {
-		choices[i] = servers[i].ServerName
-	}
-	return makeUnique(choices)
-}

internal/configuration/settings/validation/privado.go

@@ -1,35 +0,0 @@
-package validation
-
-import "github.com/qdm12/gluetun/internal/models"
-
-func PrivadoCountryChoices(servers []models.Server) (choices []string) {
-	choices = make([]string, len(servers))
-	for i := range servers {
-		choices[i] = servers[i].Country
-	}
-	return makeUnique(choices)
-}
-
-func PrivadoRegionChoices(servers []models.Server) (choices []string) {
-	choices = make([]string, len(servers))
-	for i := range servers {
-		choices[i] = servers[i].Region
-	}
-	return makeUnique(choices)
-}
-
-func PrivadoCityChoices(servers []models.Server) (choices []string) {
-	choices = make([]string, len(servers))
-	for i := range servers {
-		choices[i] = servers[i].City
-	}
-	return makeUnique(choices)
-}
-
-func PrivadoHostnameChoices(servers []models.Server) (choices []string) {
-	choices = make([]string, len(servers))
-	for i := range servers {
-		choices[i] = servers[i].Hostname
-	}
-	return makeUnique(choices)
-}

internal/configuration/settings/validation/privatevpn.go

@@ -1,27 +0,0 @@
-package validation
-
-import "github.com/qdm12/gluetun/internal/models"
-
-func PrivatevpnCountryChoices(servers []models.Server) (choices []string) {
-	choices = make([]string, len(servers))
-	for i := range servers {
-		choices[i] = servers[i].Country
-	}
-	return makeUnique(choices)
-}
-
-func PrivatevpnCityChoices(servers []models.Server) (choices []string) {
-	choices = make([]string, len(servers))
-	for i := range servers {
-		choices[i] = servers[i].City
-	}
-	return makeUnique(choices)
-}
-
-func PrivatevpnHostnameChoices(servers []models.Server) (choices []string) {
-	choices = make([]string, len(servers))
-	for i := range servers {
-		choices[i] = servers[i].Hostname
-	}
-	return makeUnique(choices)
-}

internal/configuration/settings/validation/protonvpn.go

@@ -1,43 +0,0 @@
-package validation
-
-import "github.com/qdm12/gluetun/internal/models"
-
-func ProtonvpnCountryChoices(servers []models.Server) (choices []string) {
-	choices = make([]string, len(servers))
-	for i := range servers {
-		choices[i] = servers[i].Country
-	}
-	return makeUnique(choices)
-}
-
-func ProtonvpnRegionChoices(servers []models.Server) (choices []string) {
-	choices = make([]string, len(servers))
-	for i := range servers {
-		choices[i] = servers[i].Region
-	}
-	return makeUnique(choices)
-}
-
-func ProtonvpnCityChoices(servers []models.Server) (choices []string) {
-	choices = make([]string, len(servers))
-	for i := range servers {
-		choices[i] = servers[i].City
-	}
-	return makeUnique(choices)
-}
-
-func ProtonvpnNameChoices(servers []models.Server) (choices []string) {
-	choices = make([]string, len(servers))
-	for i := range servers {
-		choices[i] = servers[i].ServerName
-	}
-	return makeUnique(choices)
-}
-
-func ProtonvpnHostnameChoices(servers []models.Server) (choices []string) {
-	choices = make([]string, len(servers))
-	for i := range servers {
-		choices[i] = servers[i].Hostname
-	}
-	return makeUnique(choices)
-}

internal/configuration/settings/validation/purevpn.go

@@ -1,35 +0,0 @@
-package validation
-
-import "github.com/qdm12/gluetun/internal/models"
-
-func PurevpnRegionChoices(servers []models.Server) (choices []string) {
-	choices = make([]string, len(servers))
-	for i := range servers {
-		choices[i] = servers[i].Region
-	}
-	return makeUnique(choices)
-}
-
-func PurevpnCountryChoices(servers []models.Server) (choices []string) {
-	choices = make([]string, len(servers))
-	for i := range servers {
-		choices[i] = servers[i].Country
-	}
-	return makeUnique(choices)
-}
-
-func PurevpnCityChoices(servers []models.Server) (choices []string) {
-	choices = make([]string, len(servers))
-	for i := range servers {
-		choices[i] = servers[i].City
-	}
-	return makeUnique(choices)
-}
-
-func PurevpnHostnameChoices(servers []models.Server) (choices []string) {
-	choices = make([]string, len(servers))
-	for i := range servers {
-		choices[i] = servers[i].Hostname
-	}
-	return makeUnique(choices)
-}

internal/configuration/settings/validation/servers.go

@@ -0,0 +1,111 @@
+package validation
+
+import (
+	"sort"
+
+	"github.com/qdm12/gluetun/internal/models"
+)
+
+func sortedInsert(ss []string, s string) []string {
+	i := sort.SearchStrings(ss, s)
+	ss = append(ss, "")
+	copy(ss[i+1:], ss[i:])
+	ss[i] = s
+	return ss
+}
+
+func ExtractCountries(servers []models.Server) (values []string) {
+	seen := make(map[string]struct{}, len(servers))
+	values = make([]string, 0, len(servers))
+	for _, server := range servers {
+		value := server.Country
+		_, alreadySeen := seen[value]
+		if alreadySeen {
+			continue
+		}
+		seen[value] = struct{}{}
+
+		values = sortedInsert(values, value)
+	}
+	return values
+}
+
+func ExtractRegions(servers []models.Server) (values []string) {
+	seen := make(map[string]struct{}, len(servers))
+	values = make([]string, 0, len(servers))
+	for _, server := range servers {
+		value := server.Region
+		_, alreadySeen := seen[value]
+		if alreadySeen {
+			continue
+		}
+		seen[value] = struct{}{}
+
+		values = sortedInsert(values, value)
+	}
+	return values
+}
+
+func ExtractCities(servers []models.Server) (values []string) {
+	seen := make(map[string]struct{}, len(servers))
+	values = make([]string, 0, len(servers))
+	for _, server := range servers {
+		value := server.City
+		_, alreadySeen := seen[value]
+		if alreadySeen {
+			continue
+		}
+		seen[value] = struct{}{}
+
+		values = sortedInsert(values, value)
+	}
+	return values
+}
+
+func ExtractISPs(servers []models.Server) (values []string) {
+	seen := make(map[string]struct{}, len(servers))
+	values = make([]string, 0, len(servers))
+	for _, server := range servers {
+		value := server.ISP
+		_, alreadySeen := seen[value]
+		if alreadySeen {
+			continue
+		}
+		seen[value] = struct{}{}
+
+		values = sortedInsert(values, value)
+	}
+	return values
+}
+
+func ExtractServerNames(servers []models.Server) (values []string) {
+	seen := make(map[string]struct{}, len(servers))
+	values = make([]string, 0, len(servers))
+	for _, server := range servers {
+		value := server.ServerName
+		_, alreadySeen := seen[value]
+		if alreadySeen {
+			continue
+		}
+		seen[value] = struct{}{}
+
+		values = sortedInsert(values, value)
+	}
+	return values
+}
+
+func ExtractHostnames(servers []models.Server) (values []string) {
+	seen := make(map[string]struct{}, len(servers))
+	values = make([]string, 0, len(servers))
+	for _, server := range servers {
+		value := server.Hostname
+		_, alreadySeen := seen[value]
+		if alreadySeen {
+			continue
+		}
+		seen[value] = struct{}{}
+
+		values = sortedInsert(values, value)
+	}
+	return values
+}

internal/configuration/settings/validation/surfshark.go

@@ -1,44 +1,9 @@
 package validation
 
 import (
-	"sort"
-
 	"github.com/qdm12/gluetun/internal/constants"
-	"github.com/qdm12/gluetun/internal/models"
 )
 
-func SurfsharkRegionChoices(servers []models.Server) (choices []string) {
-	choices = make([]string, len(servers))
-	for i := range servers {
-		choices[i] = servers[i].Region
-	}
-	return makeUnique(choices)
-}
-
-func SurfsharkCountryChoices(servers []models.Server) (choices []string) {
-	choices = make([]string, len(servers))
-	for i := range servers {
-		choices[i] = servers[i].Country
-	}
-	return makeUnique(choices)
-}
-
-func SurfsharkCityChoices(servers []models.Server) (choices []string) {
-	choices = make([]string, len(servers))
-	for i := range servers {
-		choices[i] = servers[i].City
-	}
-	return makeUnique(choices)
-}
-
-func SurfsharkHostnameChoices(servers []models.Server) (choices []string) {
-	choices = make([]string, len(servers))
-	for i := range servers {
-		choices[i] = servers[i].Hostname
-	}
-	return makeUnique(choices)
-}
-
 // TODO remove in v4.
 func SurfsharkRetroLocChoices() (choices []string) {
 	locationData := constants.SurfsharkLocationData()
@@ -49,12 +14,8 @@ func SurfsharkRetroLocChoices() (choices []string) {
 			continue
 		}
 		seen[data.RetroLoc] = struct{}{}
-		choices = append(choices, data.RetroLoc)
+		choices = sortedInsert(choices, data.RetroLoc)
 	}
 
-	sort.Slice(choices, func(i, j int) bool {
-		return choices[i] < choices[j]
-	})
-
 	return choices
 }

internal/configuration/settings/validation/torguard.go

@@ -1,29 +0,0 @@
-package validation
-
-import (
-	"github.com/qdm12/gluetun/internal/models"
-)
-
-func TorguardCountryChoices(servers []models.Server) (choices []string) {
-	choices = make([]string, len(servers))
-	for i := range servers {
-		choices[i] = servers[i].Country
-	}
-	return makeUnique(choices)
-}
-
-func TorguardCityChoices(servers []models.Server) (choices []string) {
-	choices = make([]string, len(servers))
-	for i := range servers {
-		choices[i] = servers[i].City
-	}
-	return makeUnique(choices)
-}
-
-func TorguardHostnameChoices(servers []models.Server) (choices []string) {
-	choices = make([]string, len(servers))
-	for i := range servers {
-		choices[i] = servers[i].Hostname
-	}
-	return makeUnique(choices)
-}

internal/configuration/settings/validation/vpnunlimited.go

@@ -1,29 +0,0 @@
-package validation
-
-import (
-	"github.com/qdm12/gluetun/internal/models"
-)
-
-func VPNUnlimitedCountryChoices(servers []models.Server) (choices []string) {
-	choices = make([]string, len(servers))
-	for i := range servers {
-		choices[i] = servers[i].Country
-	}
-	return makeUnique(choices)
-}
-
-func VPNUnlimitedCityChoices(servers []models.Server) (choices []string) {
-	choices = make([]string, len(servers))
-	for i := range servers {
-		choices[i] = servers[i].City
-	}
-	return makeUnique(choices)
-}
-
-func VPNUnlimitedHostnameChoices(servers []models.Server) (choices []string) {
-	choices = make([]string, len(servers))
-	for i := range servers {
-		choices[i] = servers[i].Hostname
-	}
-	return makeUnique(choices)
-}

internal/configuration/settings/validation/vyprvpn.go

@@ -1,13 +0,0 @@
-package validation
-
-import (
-	"github.com/qdm12/gluetun/internal/models"
-)
-
-func VyprvpnRegionChoices(servers []models.Server) (choices []string) {
-	choices = make([]string, len(servers))
-	for i := range servers {
-		choices[i] = servers[i].Region
-	}
-	return makeUnique(choices)
-}

internal/configuration/settings/validation/wevpn.go

@@ -1,19 +0,0 @@
-package validation
-
-import "github.com/qdm12/gluetun/internal/models"
-
-func WevpnCityChoices(servers []models.Server) (choices []string) {
-	choices = make([]string, len(servers))
-	for i := range servers {
-		choices[i] = servers[i].City
-	}
-	return makeUnique(choices)
-}
-
-func WevpnHostnameChoices(servers []models.Server) (choices []string) {
-	choices = make([]string, len(servers))
-	for i := range servers {
-		choices[i] = servers[i].Hostname
-	}
-	return makeUnique(choices)
-}

internal/configuration/settings/validation/windscribe.go

@@ -1,27 +0,0 @@
-package validation
-
-import "github.com/qdm12/gluetun/internal/models"
-
-func WindscribeRegionChoices(servers []models.Server) (choices []string) {
-	choices = make([]string, len(servers))
-	for i := range servers {
-		choices[i] = servers[i].Region
-	}
-	return makeUnique(choices)
-}
-
-func WindscribeCityChoices(servers []models.Server) (choices []string) {
-	choices = make([]string, len(servers))
-	for i := range servers {
-		choices[i] = servers[i].City
-	}
-	return makeUnique(choices)
-}
-
-func WindscribeHostnameChoices(servers []models.Server) (choices []string) {
-	choices = make([]string, len(servers))
-	for i := range servers {
-		choices[i] = servers[i].Hostname
-	}
-	return makeUnique(choices)
-}