package dht

import (
	"magneticod/dht/mainline"
	"net"
	"github.com/bradfitz/iter"
)


type TrawlingManager struct {
	// private
	output chan mainline.TrawlingResult
	services []*mainline.TrawlingService
}


func NewTrawlingManager(mlAddrs []net.UDPAddr) *TrawlingManager {
	manager := new(TrawlingManager)
	manager.output = make(chan mainline.TrawlingResult)

	if mlAddrs != nil {
		for _, addr := range mlAddrs {
			manager.services = append(manager.services, mainline.NewTrawlingService(
				addr,
				mainline.TrawlingServiceEventHandlers{
					OnResult: manager.onResult,
				},
			))
		}
	} else {
		addr := net.UDPAddr{IP: []byte("\x00\x00\x00\x00"), Port: 0}
		for range iter.N(1) {
			manager.services = append(manager.services, mainline.NewTrawlingService(
				addr,
				mainline.TrawlingServiceEventHandlers{
					OnResult: manager.onResult,
				},
			))
		}
	}

	for _, service := range manager.services {
		service.Start()
	}

	return manager
}


func (m *TrawlingManager) onResult(res mainline.TrawlingResult) {
	m.output <- res
}


func (m *TrawlingManager) Output() <-chan mainline.TrawlingResult {
	return m.output
}


func (m *TrawlingManager) Terminate() {
	for _, service := range m.services {
		service.Terminate()
	}
}