package main

import (
	"encoding/json"
	"flag"
	"fmt"
	"github.com/prometheus-community/pro-bing"
	"math"
	"time"
)

var (
	Waybar              = flag.Bool("waybar", false, "output waybar json format")
	PingCount           = flag.Int("count", 3, "how many pings to average")
	PingInterval        = flag.Int("i", 5, "ping interval")
	PingWarningLimit    = flag.Int("warn", 50, "ping warning limit")
	PingCritLimit       = flag.Int("crit", 100, "ping critical limit")
	PacketLossWarnLimit = flag.Int("pwarn", 10, "package-loss warning limit")
	PacketLossCritLimit = flag.Int("pcrit", 25, "package-loss critical limit")
	Host                = flag.String("host", "google.com", "host to ping")
)

type WaybarOut struct {
	Class string `json:"class"`
	Text  string `json:"text"`
}

func formatLine(stats *probing.Statistics) {
	if stats.PacketLoss >= 100.0 {
		// fontawesome/forkawesome doesn't have the fitting icon...
		// so this is the utf-8 icon/emoji
		fmt.Println("%{F#ff7070}🚫")
		return
	}

	var rttColor string
	var packetColor string

	switch {
	case stats.AvgRtt.Milliseconds() < 50:
		rttColor = "%{F-}"
	case stats.AvgRtt.Milliseconds() < 100:
		rttColor = "%{F#e87205}"
	default:
		rttColor = "%{F#d60606}"
	}

	switch {
	case stats.PacketLoss == 0:
		packetColor = "%{F-}"
	case stats.PacketLoss < 10:
		packetColor = "%{F#f9dd04}"
	case stats.PacketLoss < 25:
		packetColor = "%{F#e87205}"
	default:
		packetColor = "%{F#d60606}"
	}

	fmt.Printf("%s%dms %%{F-}| %s%d%%\n", rttColor, stats.AvgRtt.Milliseconds(), packetColor, int(math.Round(stats.PacketLoss)))
}

func formatLineWaybar(stats *probing.Statistics) {
	res := new(WaybarOut)

	res.Text = fmt.Sprintf("\uE4E2 %dms \uF1B2 %d%%", int(stats.AvgRtt.Milliseconds()), int(math.Round(stats.PacketLoss)))
	res.Class = "good"

	switch {
	case int(math.Round(stats.PacketLoss)) >= *PacketLossWarnLimit || int(stats.AvgRtt.Milliseconds()) >= *PingWarningLimit:
		res.Class = "warning"
	case int(math.Round(stats.PacketLoss)) >= *PacketLossCritLimit || int(stats.AvgRtt.Milliseconds()) >= *PingCritLimit:
		res.Class = "critical"
	}

	jOut, err := json.Marshal(res)
	if err != nil {
		return
	}

	fmt.Println(string(jOut))
}

func main() {
	flag.Parse()

	for {
		time.Sleep(time.Duration(*PingInterval) * time.Second)

		pinger, err := probing.NewPinger(*Host)
		if err != nil {
			fmt.Println(err)
			continue
		}
		pinger.Count = *PingCount
		if *Waybar {
			pinger.OnFinish = formatLineWaybar
		} else {
			pinger.OnFinish = formatLine
		}

		if pinger.Run() != nil {
			fmt.Println(err)
			continue
		}
	}
}