const LockfilePath16x = "/run/xtables.lock"

const MinCheckVersion = "1.4.11"

const MinWait2Version = "1.4.22"

const MinWaitVersion = "1.4.20"

type Chain string

const (
	ChainPostrouting Chain = "POSTROUTING"
	ChainPrerouting  Chain = "PREROUTING"
	ChainOutput      Chain = "OUTPUT"
	ChainInput       Chain = "INPUT"
)

type FlushFlag bool

const FlushTables FlushFlag = true

const NoFlushTables FlushFlag = false

type Interface interface {
	// GetVersion returns the "X.Y.Z" version string for iptables.
	GetVersion() (string, error)
	// EnsureChain checks if the specified chain exists and, if not, creates it.  If the chain existed, return true.
	EnsureChain(table Table, chain Chain) (bool, error)
	// FlushChain clears the specified chain.  If the chain did not exist, return error.
	FlushChain(table Table, chain Chain) error
	// DeleteChain deletes the specified chain.  If the chain did not exist, return error.
	DeleteChain(table Table, chain Chain) error
	// EnsureRule checks if the specified rule is present and, if not, creates it.  If the rule existed, return true.
	EnsureRule(position RulePosition, table Table, chain Chain, args ...string) (bool, error)
	// DeleteRule checks if the specified rule is present and, if so, deletes it.
	DeleteRule(table Table, chain Chain, args ...string) error
	// IsIpv6 returns true if this is managing ipv6 tables
	IsIpv6() bool
	// SaveInto calls `iptables-save` for table and stores result in a given buffer.
	SaveInto(table Table, buffer *bytes.Buffer) error
	// Restore runs `iptables-restore` passing data through []byte.
	// table is the Table to restore
	// data should be formatted like the output of SaveInto()
	// flush sets the presence of the "--noflush" flag. see: FlushFlag
	// counters sets the "--counters" flag. see: RestoreCountersFlag
	Restore(table Table, data []byte, flush FlushFlag, counters RestoreCountersFlag) error
	// RestoreAll is the same as Restore except that no table is specified.
	RestoreAll(data []byte, flush FlushFlag, counters RestoreCountersFlag) error
	// AddReloadFunc adds a function to call on iptables reload
	AddReloadFunc(reloadFunc func())
	// Destroy cleans up resources used by the Interface
	Destroy()
}

type Protocol byte

const (
	ProtocolIpv4 Protocol = iota + 1
	ProtocolIpv6
)

type RestoreCountersFlag bool

const NoRestoreCounters RestoreCountersFlag = false

const RestoreCounters RestoreCountersFlag = true

type RulePosition string

const (
	Prepend RulePosition = "-I"
	Append  RulePosition = "-A"
)

type Table string

const (
	TableNAT    Table = "nat"
	TableFilter Table = "filter"
)