path: root/statusbar.go

package main

import (
	"fmt"
	"net"
	"syscall"
	"strings"
	"strconv"
	"os"
	"os/exec"
	"io/ioutil"
	"time"

	"github.com/BurntSushi/toml"
)

type MusicPlayer interface {
	nowPlaying() string
	status() int
}

type MPD struct{
	Host string
	Port int
}

type MOCP struct{}

type Config struct {
	Sections []string
	Delay int
	Separator string
	IP IPConfig
	Mounts MountConfig
	Music MusicConfig
	Clock ClockConfig
}

type IPConfig struct {
	Label string
	Interfaces []string
	IPv4Only bool `toml:"ipv4only"`
}

type MountConfig struct {
	Label string
	MountPoints []string `toml:"mountpoints"`
}

type MusicConfig struct {
	LabelPlaying string `toml:"labelplaying"`
	LabelPaused string `toml:"labelpaused"`
	LabelStopped string `toml:"labelstopped"`
	Type string
	Host string
	Port int
}

type ClockConfig struct {
	Label string
	Format string
}

func diskSizes(config MountConfig) string {
	var b strings.Builder
	var statfs syscall.Statfs_t
	const div = float64(1024 * 1024 * 1024)
	const unit = "G"
	sep := ""
	for _, mount := range config.MountPoints {
		b.WriteString(sep)
		err := syscall.Statfs(mount, &statfs)
		if err != nil {
			panic(err)
		}
		availBytes := float64(statfs.Bavail * uint64(statfs.Bsize))
		avail := strconv.FormatFloat(availBytes / div, 'f', 2, 64)
		b.WriteString(fmt.Sprintf("%v : %v %v", mount, avail, unit))
		sep = " "
	}
	return b.String()
}

func ips(config IPConfig) string {
	var b strings.Builder
	sep := ""
	for _, interfaceName := range config.Interfaces {
		b.WriteString(sep)
		b.WriteString(interfaceName)
		b.WriteString(": ")
		if len(config.Interfaces) > 1 {
			b.WriteString(" [")
		}
		b.WriteString(ip(interfaceName, config.IPv4Only))
		if len(config.Interfaces) > 1 {
			b.WriteString(" ]")
		}
		sep = " "
	}
	return b.String()
}

func ip(interfaceName string, IPv4Only bool) string {
	var b strings.Builder
	sep := ""
	in, err := net.InterfaceByName(interfaceName)
	if err != nil {
		panic(err)
	}
	addrs, err := in.Addrs()
	if err != nil {
		panic(err)
	}
	for _, addr := range addrs {
		var ip net.IP
		switch v := addr.(type) {
		case *net.IPAddr:
			ip = v.IP
		case *net.IPNet:
			ip = v.IP
		default:
		}
		if IPv4Only {
			if ip.To4() != nil {
				b.WriteString(sep)
				b.WriteString(ip.String())
				sep = " "
			}
		} else {
			b.WriteString(sep)
			b.WriteString(ip.String())
			sep = " "
		}
	}
	return b.String()
}

func clock(format string) string {
	t := time.Now()
	return t.Format(format)
}

func (mpd MPD) nowPlaying() string {
	cmd := exec.Command("mpc", "-h", mpd.Host, "-p", strconv.Itoa(mpd.Port), "current")
	out, err := cmd.Output()
	if err != nil {
		panic(err)
	}
	sOut := string(out)
	sOut = strings.ReplaceAll(sOut, "\n", "")
	return sOut
}

// Returns 0 if playing, 1 if paused and 2 otherwise
func (mpd MPD) status() int {
	cmd := exec.Command("mpc", "-h", mpd.Host, "-p", strconv.Itoa(mpd.Port), "status")
	out, err := cmd.Output()
	if err != nil {
		return -1
	}
	sOut := string(out)
	if strings.Contains(sOut, "playing") {
		return 0
	} else if strings.Contains(sOut, "paused") {
		return 1
	} else {
		return 2
	}
}

func (mocp MOCP) nowPlaying() string {
	cmd := exec.Command("mocp", "-Q", "%artist - %song")
	out, err := cmd.Output()
	if err != nil {
		panic(err)
	}
	sOut := string(out)
	sOut = strings.ReplaceAll(sOut, "\n", "")
	return sOut
}

// Returns 0 if playing, 1 if paused and 2 otherwise
func (mocp MOCP) status() int {
	cmd := exec.Command("mocp", "-i")
	out, err := cmd.Output()
	if err != nil {
		return -1
	}
	sOut := string(out)
	if strings.Contains(sOut, "PLAY") {
		return 0
	} else if strings.Contains(sOut, "PAUSE") {
		return 1
	} else {
		return 2
	}
}


func buildClock(config ClockConfig) string {
	var b strings.Builder
	b.WriteString(config.Label)
	b.WriteString(clock(config.Format))
	return b.String()
}

func buildIP(config IPConfig) string {
	var b strings.Builder
	b.WriteString(config.Label)
	b.WriteString("[ ")
	b.WriteString(ips(config))
	b.WriteString(" ]")
	return b.String()
}

func buildMounts(config MountConfig) string {
	var b strings.Builder
	b.WriteString(config.Label)
	b.WriteString("[ ")
	b.WriteString(diskSizes(config))
	b.WriteString(" ]")
	return b.String()
}

func buildMusic(config MusicConfig) string {
	var b strings.Builder
	var player MusicPlayer
	switch config.Type {
	case "mpd":
		host := config.Host
		if host == "" {
			host = "127.0.0.1"
		}
		port := config.Port
		if port == 0 {
			port = 6600
		}
		player = MPD{Host: host, Port: port}
	case "mocp":
		player = MOCP{}
	default:
	}
	exists := player != nil
	if !exists {
		return "Unknown music player type"
	}
	switch player.status() {
	case 0:
		b.WriteString(config.LabelPlaying)
	case 1:
		b.WriteString(config.LabelPaused)
	case 2:
		b.WriteString(config.LabelStopped)
	default:
		exists = false
	}
	if exists {
		b.WriteString(player.nowPlaying())
	}
	return b.String()
}

func main() {
	var configPath = "/etc/statusbar.conf"
	var content []byte
	var err error
	if _, err := os.Stat(configPath); err != nil {
		content, err = ioutil.ReadAll(os.Stdin)
	} else {
		content, err = ioutil.ReadFile(configPath)
	}
	if err != nil {
		panic(err)
	}
	var config Config
	_, err = toml.Decode(string(content), &config)
	if err != nil {
		panic(err)
	}
	for true {
		var b strings.Builder
		for i, section := range config.Sections {
			switch section {
			case "clock":
				b.WriteString(buildClock(config.Clock))
			case "ip":
				b.WriteString(buildIP(config.IP))
			case "mounts":
				b.WriteString(buildMounts(config.Mounts))
			case "music":
				b.WriteString(buildMusic(config.Music))
			default:
			}
			if i < len(config.Sections) - 1 {
				b.WriteString(config.Separator)
			}
		}
		fmt.Println(b.String())
		time.Sleep(time.Duration(config.Delay) * time.Second)
	}
}