package traverse

import (
	"net"
	"strings"

	miekgdns "github.com/miekg/dns"
)

type ResolutionState int

const (
	StateUnresolved ResolutionState = iota
	StateResolving
	StateResolved
)

func (s ResolutionState) String() string {
	switch s {
	case StateUnresolved:
		return "unresolved"
	case StateResolving:
		return "resolving"
	case StateResolved:
		return "resolved"
	default:
		return "unknown"
	}
}

type Referral struct {
	Name     string
	Qtype    uint16
	Qclass   uint16
	Bailiwick string

	Addresses []net.IP
	State     ResolutionState

	NSName  string
	Parent  *Referral
	Depth   int
	Prob    float64
}

func NewReferral(name string, qtype uint16, bailiwick string, depth int, prob float64, parent *Referral) *Referral {
	return &Referral{
		Name:      miekgdns.Fqdn(strings.ToLower(name)),
		Qtype:     qtype,
		Qclass:    miekgdns.ClassINET,
		Bailiwick: miekgdns.Fqdn(strings.ToLower(bailiwick)),
		Depth:     depth,
		Prob:      prob,
		Parent:    parent,
		State:     StateUnresolved,
	}
}

func (r *Referral) InBailiwick(name string) bool {
	if r.Bailiwick == "" || r.Bailiwick == "." {
		return true
	}
	fqdn := miekgdns.Fqdn(strings.ToLower(name))
	return miekgdns.IsSubDomain(r.Bailiwick, fqdn)
}

func (r *Referral) HasAddresses() bool {
	return len(r.Addresses) > 0
}

func (r *Referral) SetAddresses(addrs []net.IP) {
	r.Addresses = addrs
	if len(addrs) > 0 {
		r.State = StateResolved
	} else {
		r.State = StateUnresolved
	}
}