package ingest

import (
	"context"
	"fmt"
	"log"
	"net"
	"strings"
	"time"

	"git.apinb.com/ops/logs/internal/config"
	"github.com/gosnmp/gosnmp"
)

func StartTrapUDP(ctx context.Context) error {
	addr := strings.TrimSpace(config.Spec.Ingest.TrapListenAddr)
	if addr == "" {
		return nil
	}
	tl := gosnmp.NewTrapListener()
	tl.OnNewTrap = func(pkt *gosnmp.SnmpPacket, u *net.UDPAddr) {
		if u == nil || pkt == nil {
			return
		}
		ua := *u
		Global.HandleTrap(&ua, pkt)
		markWorkerSucceeded("trap_udp")
	}
	tl.Params = gosnmp.Default
	tl.Params.Logger = gosnmp.NewLogger(log.Default())
	started := make(chan error, 1)
	startWorker("trap_udp", func() error {
		go func() {
			<-ctx.Done()
			tl.Close()
		}()
		err := tl.Listen(addr)
		if ctx.Err() != nil {
			return nil
		}
		return err
	})
	go func() {
		select {
		case <-tl.Listening():
			started <- nil
		case <-ctx.Done():
			started <- ctx.Err()
		case <-time.After(5 * time.Second):
			tl.Close()
			started <- fmt.Errorf("Trap UDP 监听 %s 启动超时", addr)
		}
	}()
	if err := <-started; err != nil {
		return err
	}
	return nil
}