package randomness

import (
	"github.com/ethereum/go-ethereum/rpc"
	msg_pb "github.com/harmony-one/harmony/api/proto/message"
	"github.com/harmony-one/harmony/drand"
	"github.com/harmony-one/harmony/internal/utils"
)

// Service is the randomness generation service.
type Service struct {
	stopChan    chan struct{}
	stoppedChan chan struct{}
	DRand       *drand.DRand
	messageChan chan *msg_pb.Message
}

// New returns randomness generation service.
func New(dRand *drand.DRand) *Service {
	return &Service{DRand: dRand}
}

// StartService starts randomness generation service.
func (s *Service) StartService() {
	s.stopChan = make(chan struct{})
	s.stoppedChan = make(chan struct{})
	s.DRand.WaitForEpochBlock(s.DRand.ConfirmedBlockChannel, s.stopChan, s.stoppedChan)
}

// StopService stops randomness generation service.
func (s *Service) StopService() {
	utils.Logger().Info().Msg("Stopping random generation service")
	s.stopChan <- struct{}{}
	<-s.stoppedChan
	utils.Logger().Info().Msg("Random generation stopped")
}

// NotifyService notify service
func (s *Service) NotifyService(params map[string]interface{}) {
	return
}

// SetMessageChan sets up message channel to service.
func (s *Service) SetMessageChan(messageChan chan *msg_pb.Message) {
	s.messageChan = messageChan
}

// APIs for the services.
func (s *Service) APIs() []rpc.API {
	return nil
}