package module

import (
	"fmt"
	"gitee.com/fpy-go/plugin/pkg/extend/model"
	gplugin "github.com/hashicorp/go-plugin"
	"net/rpc"
	"os"
	"time"
)

var parentPid int

func init() {
	parentPid = os.Getppid()
}

// Notice 通知服务插件接口
type Notice interface {
	Info() model.PluginInfo
	Send(data []byte) model.JsonRes
}

// NoticeRPC 基于RPC实现
type NoticeRPC struct {
	Client *rpc.Client
}

func (g *NoticeRPC) Info() model.PluginInfo {
	var resp model.PluginInfo
	err := g.Client.Call("Plugin.Info", new(interface{}), &resp)
	if err != nil {
		panic(err)
	}
	return resp
}
func (g *NoticeRPC) Send(data []byte) model.JsonRes {
	var resp model.JsonRes
	err := g.Client.Call("Plugin.Send", data, &resp)
	if err != nil {
		panic(err)
	}

	return resp
}

// NoticeRPCServer  GreeterRPC的RPC服务器，符合 net/rpc的要求
type NoticeRPCServer struct {
	Impl Notice
}

func (s *NoticeRPCServer) Info(args interface{}, resp *model.PluginInfo) error {
	*resp = s.Impl.Info()
	return nil
}
func (s *NoticeRPCServer) Send(data []byte, resp *model.JsonRes) error {
	*resp = s.Impl.Send(data)
	return nil
}

// NoticePlugin 插件的虚拟实现。用于PluginMap的插件接口。在运行时，来自插件实现的实际实现会覆盖
type NoticePlugin struct{}

// Server 此方法由插件进程延迟的调用
func (NoticePlugin) Server(*gplugin.MuxBroker) (interface{}, error) {
	checkParentAlive()
	return &NoticeRPCServer{}, nil
}

// Client 此方法由宿主进程调用
func (NoticePlugin) Client(b *gplugin.MuxBroker, c *rpc.Client) (interface{}, error) {
	return &NoticeRPC{Client: c}, nil
}

// checkParentAlive 检查父进程(也就是 client )是否退出，如果退出了，自己也需要退出。
func checkParentAlive() {
	go func() {
		for {
			if parentPid == 1 || os.Getppid() != parentPid {
				fmt.Println("parent no alive, exit")
				os.Exit(0)
			}
			_, err := os.FindProcess(parentPid)
			if err != nil {
				fmt.Println("parent no alive, exit")
				os.Exit(0)
			}

			time.Sleep(5 * time.Second)
		}
	}()
}