package service

import (
	"fmt"
	"git.hlsq.asia/mmorpg/service-common/config"
	"git.hlsq.asia/mmorpg/service-common/discover"
	"git.hlsq.asia/mmorpg/service-common/log"
	"git.hlsq.asia/mmorpg/service-common/utils"
	"go.opentelemetry.io/contrib/instrumentation/google.golang.org/grpc/otelgrpc"
	"google.golang.org/grpc"
	"google.golang.org/grpc/health"
	"google.golang.org/grpc/health/grpc_health_v1"
	"google.golang.org/grpc/keepalive"
	"net"
	"sync"
	"time"
)

type IService interface {
	Init(ready *sync.WaitGroup)
	SetReady()
	Close()
}

type Base struct {
	Target                   string
	ServiceName              string
	SID                      int64
	Serve                    *grpc.Server
	Cfg                      *config.GrpcConfig
	OnCustomGrpcServerOption func() []grpc.ServerOption
	OnInit                   func(serve *grpc.Server)
	OnClose                  func()

	wg          *sync.WaitGroup
	healthcheck *health.Server
}

func (s *Base) Init(ready *sync.WaitGroup) {
	s.wg = &sync.WaitGroup{}
	s.wg.Add(1)
	s.SID = utils.SnowflakeInstance().Generate().Int64()
	go func() {
		defer s.wg.Done()
		defer s.OnClose()
		defer discover.UnRegisterGrpcServer(s.SID)

		// 监听端口
		lis, err := net.Listen("tcp", fmt.Sprintf(":%d", s.Cfg.Port))
		if err != nil {
			log.Errorf("%v ListenPort err: %v", s.Target, err)
			return
		}

		options := []grpc.ServerOption{
			grpc.ChainUnaryInterceptor(
				s.RecoveryInterceptor,
				s.LoggingInterceptor,
			),
			grpc.StatsHandler(otelgrpc.NewServerHandler()),
			grpc.KeepaliveEnforcementPolicy(keepalive.EnforcementPolicy{
				MinTime:             20 * time.Second,
				PermitWithoutStream: true,
			}),
		}
		options = append(options, s.OnCustomGrpcServerOption()...)
		s.Serve = grpc.NewServer(options...)
		s.OnInit(s.Serve)

		// 健康检查
		s.healthcheck = health.NewServer()
		s.healthcheck.SetServingStatus("", grpc_health_v1.HealthCheckResponse_NOT_SERVING)
		grpc_health_v1.RegisterHealthServer(s.Serve, s.healthcheck)

		// 服务注册
		if err = discover.RegisterGrpcServer(s.Target, s.SID, fmt.Sprintf("%v:%d", s.Cfg.Address, s.Cfg.Port), s.Cfg.TTL); err != nil {
			log.Errorf("%v RegisterGrpcServer err: %v", s.Target, err)
			return
		}
		// 准备好了
		ready.Done()
		if err = s.Serve.Serve(lis); err != nil {
			log.Errorf("%v Serve err: %v", s.Target, err)
			return
		}
		log.Infof("%v server stop.", s.Target)
	}()
}

func (s *Base) SetReady() {
	if s.healthcheck != nil {
		s.healthcheck.SetServingStatus("", grpc_health_v1.HealthCheckResponse_SERVING)
	}
}

func (s *Base) Close() {
	if s.healthcheck != nil {
		s.healthcheck.SetServingStatus("", grpc_health_v1.HealthCheckResponse_NOT_SERVING)
	}
	if s.Serve != nil {
		s.Serve.GracefulStop()
		s.wg.Wait()
	}
}