package nmdata

import (
	"net"
	"net/netip"
	"slices"
	"time"
)

const (
	peerCapabilitySourcePrefixes int32 = 1
	peerCapabilityIPv6Overlay    int32 = 2
)

// Peer is the slim twin of peer.Peer.
type Peer struct {
	ID                     string
	Key                    string
	SSHKey                 string
	DNSLabel               string
	UserID                 string
	SSHEnabled             bool
	LoginExpirationEnabled bool
	LastLogin              *time.Time
	IP                     netip.Addr
	IPv6                   netip.Addr
	Meta                   PeerSystemMeta
	Location               PeerLocation
}

// PeerSystemMeta is the slim twin of peer.PeerSystemMeta.
type PeerSystemMeta struct {
	WtVersion        string
	GoOS             string
	OSVersion        string
	KernelVersion    string
	NetworkAddresses []NetworkAddress
	Files            []File
	Capabilities     []int32
	Flags            Flags
}

// Flags is the slim twin of peer.Flags.
type Flags struct {
	ServerSSHAllowed bool
	DisableIPv6      bool
}

// NetworkAddress is the slim twin of peer.NetworkAddress.
type NetworkAddress struct {
	NetIP netip.Prefix
}

// File is the slim twin of peer.File.
type File struct {
	Path             string
	ProcessIsRunning bool
}

// PeerLocation is the slim twin of peer.Location.
type PeerLocation struct {
	CountryCode  string
	CityName     string
	ConnectionIP net.IP
}

func (p *Peer) HasCapability(capability int32) bool {
	return slices.Contains(p.Meta.Capabilities, capability)
}

func (p *Peer) SupportsIPv6() bool {
	return !p.Meta.Flags.DisableIPv6 && p.HasCapability(peerCapabilityIPv6Overlay)
}

func (p *Peer) SupportsSourcePrefixes() bool {
	return p.HasCapability(peerCapabilitySourcePrefixes)
}

func (p *Peer) AddedWithSSOLogin() bool {
	return p.UserID != ""
}

func (p *Peer) FQDN(dnsDomain string) string {
	if dnsDomain == "" {
		return ""
	}
	return p.DNSLabel + "." + dnsDomain
}

func (p *Peer) GetLastLogin() time.Time {
	if p.LastLogin != nil {
		return *p.LastLogin
	}
	return time.Time{}
}

func (p *Peer) LoginExpired(expiresIn time.Duration) (bool, time.Duration) {
	if !p.AddedWithSSOLogin() || !p.LoginExpirationEnabled {
		return false, 0
	}
	expiresAt := p.GetLastLogin().Add(expiresIn)
	now := time.Now()
	timeLeft := expiresAt.Sub(now)
	return timeLeft <= 0, timeLeft
}