// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.

package ipset

import (
	"errors"
	"fmt"
	"net/netip"
)

type IPSet struct {
	V4Name string
	V6Name string
	Prefix string
	Deps   NetlinkIpsetDeps
}

const (
	V4Name = "%s-v4"
	V6Name = "%s-v6"
)

func (s *Singleton[T]) GetNonBlocking() *T {
	select {
	case <-s.set:
		return s.v
	default:
		return nil
	}
}

// IsSet will return whether the singleton has been set.
func (s *Singleton[T]) IsSet() bool {
	select {
	case <-s.set:
		return true
	default:
		return false
	}
}

// Set the value and unblock all Get requests.

			continue
		}

		var isSet bool
		for _, userMetadataPrefix := range userMetadataKeyPrefixes {
			if !stringsHasPrefixFold(k, userMetadataPrefix) {
				continue
			}
			w.Header()[strings.ToLower(k)] = []string{v}
			isSet = true
			break
		}

		if !isSet {
			w.Header().Set(k, v)
		}
	}

	var start, rangeLen int64

    }

    val bit = 1 shl id
    set = set or bit
    values[id] = value
    return this
  }

  /** Returns true if a value has been assigned for the setting `id`. */
  fun isSet(id: Int): Boolean {
    val bit = 1 shl id
    return set and bit != 0
  }

  /** Returns the value for the setting `id`, or 0 if unset. */
  operator fun get(id: Int): Int = values[id]

	err := netlink.IpsetFlush(name)
	if err != nil {
		return fmt.Errorf("failed to flush ipset %s: %w", name, err)
	}
	return nil
}

// Alpine and some distros struggles with this - ipset CLI utilities support this, but
// the kernel can be out of sync with the CLI utility, leading to errors like:
//
// ipset v7.10: Argument `comment' is supported in the kernel module of the set type hash:ip

	}
	sort.Slice(clusters, func(i, j int) bool {
		iDirection, iSubset, iName, iPort := safelyParseSubsetKey(clusters[i].Name)
		jDirection, jSubset, jName, jPort := safelyParseSubsetKey(clusters[j].Name)
		if iName == jName {
			if iSubset == jSubset {
				if iPort == jPort {
					return iDirection < jDirection
				}
				return iPort < jPort
			}
			return iSubset < jSubset
		}
		return iName < jName
	})

	}
	return w.Flush()
}

func configSource(flag string, v env.VariableInfo) string {
	// Environment variables have high precedence in Viper
	if v.IsSet() {
		return "$" + v.GetName()
	}

	if viper.InConfig(flag) {
		return root.IstioConfig
	}

	return "default"

	sort.Slice(endpoints, func(i, j int) bool {
		iDirection, iSubset, iName, iPort := safelyParseSubsetKey(endpoints[i].ClusterName)
		jDirection, jSubset, jName, jPort := safelyParseSubsetKey(endpoints[j].ClusterName)
		if iName == jName {
			if iSubset == jSubset {
				if iPort == jPort {
					return iDirection < jDirection
				}
				return iPort < jPort
			}
			return iSubset < jSubset
		}
		return iName < jName
	})

import assertk.assertions.isFalse
import assertk.assertions.isTrue
import org.junit.jupiter.api.Test

class SettingsTest {
  @Test
  fun unsetField() {
    val settings = Settings()
    assertThat(settings.isSet(Settings.MAX_CONCURRENT_STREAMS)).isFalse()
    assertThat(settings.getMaxConcurrentStreams()).isEqualTo(Int.MAX_VALUE)
  }

  @Test
  fun setFields() {
    val settings = Settings()

func (set TargetIDSet) Union(sset TargetIDSet) TargetIDSet {
	nset := set.Clone()

	for k := range sset {
		nset.add(k)
	}

	return nset
}

// Difference - returns difference with given set as new set.
func (set TargetIDSet) Difference(sset TargetIDSet) TargetIDSet {
	nset := NewTargetIDSet()
	for k := range set {
		if _, ok := sset[k]; !ok {
			nset.add(k)
		}
	}

	return nset