package common

import (
	peerpkg "github.com/kaspanet/kaspad/app/protocol/peer"
	routerpkg "github.com/kaspanet/kaspad/infrastructure/network/netadapter/router"
	"os"
	"sync"
	"time"

	"github.com/pkg/errors"
)

// DefaultTimeout is the default duration to wait for enqueuing/dequeuing
// to/from routes.
const DefaultTimeout = 120 * time.Second

// ErrPeerWithSameIDExists signifies that a peer with the same ID already exist.
var ErrPeerWithSameIDExists = errors.New("ready peer with the same ID already exists")

type flowExecuteFunc func(peer *peerpkg.Peer)

// Flow is a a data structure that is used in order to associate a p2p flow to some route in a router.
type Flow struct {
	Name        string
	ExecuteFunc flowExecuteFunc
}

// FlowInitializeFunc is a function that is used in order to initialize a flow
type FlowInitializeFunc func(route *routerpkg.Route, peer *peerpkg.Peer) error

var isDNSSeeder bool
var isDNSSeederOnce sync.Once

// IsDNSSeeder returns whether this node supports a DNS seeder. If this is the case, the node
// doesn't need to actually stay synced, and is mainly used for scanning the p2p network.
func IsDNSSeeder() bool {
	isDNSSeederOnce.Do(func() {
		isDNSSeederEnv := os.Getenv("DNSSEEDER")
		if isDNSSeederEnv != "" {
			isDNSSeeder = true
		}
	})
	return isDNSSeeder
}