package grpc

import (
	"fmt"
	"log"
	"net"
	"sync"

	"google.golang.org/grpc"
	"google.golang.org/grpc/reflection"
)

type GrpcService interface {
	Register(srv *grpc.Server)
}

type Config struct {
	Address string
	Port    int
	AppName string
	Opts    []grpc.ServerOption
}

var rpc *grpc.Server
var conf *Config

func Init(config *Config) *grpc.Server {
	if config == nil {
		config = &Config{
			Address: "0.0.0.0",
			Port:    0,
			AppName: "unknown",
			Opts:    []grpc.ServerOption{grpc.MaxRecvMsgSize(1024 * 1024), grpc.MaxSendMsgSize(1024 * 1024)},
		}
	}
	conf = config

	if rpc == nil {
		rpc = grpc.NewServer(conf.Opts...)
	}
	return rpc
}

func IPAddress() string {
	return conf.Address
}

func Port() int {
	return conf.Port
}

func Start() {
	//注册反射 用于grpcurl调试
	reflection.Register(rpc)
	wg := sync.WaitGroup{}
	wg.Add(1)
	// grpc服务启动
	go func() {
		addr, err := net.ResolveTCPAddr("tcp", fmt.Sprintf("%s:%d", conf.Address, conf.Port))
		if err != nil {
			log.Fatal("net.ResolveTCPAddr", err)
		}
		lis, err := net.ListenTCP("tcp", addr)
		if err != nil {
			log.Fatal("fail to open port: ", err)
		}
		defer lis.Close()
		conf.Port = lis.Addr().(*net.TCPAddr).Port
		wg.Done()
		log.Printf("starting grpc service on %s:%d", addr.IP, conf.Port)
		err = rpc.Serve(lis)
		if err != nil {
			log.Fatal("fail to open microservice: ", err)
		}
	}()
	wg.Wait()
}