~/.bin/rn: Run and notify if it runs "long"

Where long is defined as "longer than one second" for now.  Might help
with these media download thingies?  Also only notifies if the window is
not focused. :)

.bin/Makefile

@@ -1,4 +1,7 @@
all: timely up ydl
all: rn timely up ydl
rn: rn.go
	go build $<
timely: timely.go
	go build timely.go

.bin/rn.go

@@ -0,0 +1,63 @@
package main
import (
	"fmt"
	"os"
	"os/exec"
	"strings"
	"time"
)
func main() {
	if len(os.Args) < 2 {
		fmt.Fprintf(os.Stderr, "Usage: %s <cmd> [<args>*]\n", os.Args[0])
		os.Exit(1)
	}
	win := xGetActiveWindow()
	cmd := exec.Command(os.Args[1], os.Args[2:]...)
	cmd.Stdin = os.Stdin
	cmd.Stdout = os.Stdout
	cmd.Stderr = os.Stderr
	start := time.Now()
	err := cmd.Run()
	duration := time.Since(start)
	winAfter := xGetActiveWindow()
	msg := fmt.Sprintf("Finished running %q in %s", cmdToString(cmd), duration)
	if duration > 1*time.Second && win != winAfter {
		notifyCompletion(msg)
	}
	fmt.Println(msg)
	success := true
	if err != nil {
		success = false
		fmt.Fprintf(os.Stderr, "Error: %s\n", err)
	}
	if !success {
		os.Exit(1)
	}
}
func notifyCompletion(msg string) {
	notifyCmd := exec.Command("notify-send", msg)
	notifyCmd.Run()
}
func xGetActiveWindow() string {
	cmd := exec.Command("xdotool", "getactivewindow")
	out, err := cmd.Output()
	if err != nil {
		return ""
	}
	return string(out)
}
func cmdToString(cmd *exec.Cmd) string {
	return strings.Join(cmd.Args, " ")
}