bar/bar.go

package bar

import (
	"fmt"
	"log"
	"os"
	"os/exec"
	"time"

	// bar
	"golang.org/x/term"

	// osc
	"github.com/hypebeast/go-osc/osc"
)

// Your basic screenbar
type ScreenBar struct {
	title        string
	ticks        int
	ticker       *time.Ticker
	tickerActive bool
	columns      int
}

// ScreenBar construction
func NewScreenBar(title string) *ScreenBar {
	bar := new(ScreenBar)
	bar.title = title
	bar.ticks = 0
	bar.tickerActive = true

	bar.ticker = time.NewTicker(time.Second)
	bar.update()

	// Goroutine to handle ticker updates
	go func() {
		for range bar.ticker.C {
			bar.ticks += 1
			bar.update()
		}
	}()

	return bar
}

// (Re)paint a screen by drawing bar
func (bar *ScreenBar) update() {
	// Config size if in terminal
	if term.IsTerminal(0) {
		bar.columns, _, _ = term.GetSize(0)
	}

	// Go home and draw (type) a bar
	fmt.Print("")
	fmt.Print("")
	s := fmt.Sprintf(" %%%ds %%6d ", 10-bar.columns)
	fmt.Printf(s, bar.title, bar.ticks)
	fmt.Print("")

	// An attempt to display Screenbar button using kitty image protocol
	cmd := exec.Command("sh", "-c", fmt.Sprintf("kitten icat -z -1 -n --place 2x1@%dx0 --stdin no images/bar_button.png < /dev/null > /dev/tty", bar.columns))
	if out, err := cmd.Output(); err != nil {
		os.Stdout.Write(out)
		log.Print(err)
	} else {
		os.Stdout.Write(out)
	}
}

// Set title visible on the bar
func (bar *ScreenBar) setTitle(msg *osc.Message) {
	for _, arg := range msg.Arguments {
		switch arg.(type) {
		case string:
			bar.title = arg.(string)
			bar.update()
		}
	}
}

// Ticker's gonna tick
func (bar *ScreenBar) tick() {
	bar.ticks += 1
	bar.update()
}

// Ticker's gonna need to be reset sometimes
func (bar *ScreenBar) reset(msg *osc.Message) {
	bar.ticks = 0
	bar.ticker.Reset(time.Second)
	bar.update()
}