use cobra for parsing flags

src/mcquay.me/yay/cmd/yay/main.go

@@ -2,30 +2,54 @@ package main
 
 import (
 	"fmt"
-	"os"
+	"time"
 
 	"mcquay.me/yay"
+
+	"github.com/spf13/cobra"
 )
 
 const usage = "usage: yay <shrug|dance>"
 
 func main() {
-	cmd := "yay"
-	if len(os.Args) > 1 {
-		cmd = os.Args[1]
+	frameRate := 200
+	main := &cobra.Command{
+		Use:   "yay",
+		Short: "cute cli animations",
+		Run: func(cmd *cobra.Command, args []string) {
+			t := yay.NewViewPort(yay.NewYay(), time.Duration(frameRate)*time.Millisecond)
+			t.Run()
+		},
 	}
-	var t *yay.ViewPort
+	main.PersistentFlags().IntVarP(&frameRate, "timeout", "t", 200, "timeout between animations")
 
-	switch cmd {
-	case "yay":
-		t = yay.NewViewPort(yay.NewYay())
-	case "shrug":
-		t = yay.NewViewPort(yay.NewShrug())
-	case "dance":
-		t = yay.NewViewPort(yay.NewDance())
-	default:
-		fmt.Fprintf(os.Stderr, "%s\n", usage)
-		os.Exit(1)
+	shrug := &cobra.Command{
+		Use:   "shrug",
+		Short: "you know, a shrug",
+		Run: func(cmd *cobra.Command, args []string) {
+			t := yay.NewViewPort(yay.NewShrug(), time.Duration(frameRate)*time.Millisecond)
+			t.Run()
+		},
 	}
-	t.Run()
+
+	dance := &cobra.Command{
+		Use:   "dance",
+		Short: "shake it, shake it!!",
+		Run: func(cmd *cobra.Command, args []string) {
+			t := yay.NewViewPort(yay.NewDance(), time.Duration(frameRate)*time.Millisecond)
+			t.Run()
+		},
+	}
+
+	version := &cobra.Command{
+		Use:   "version",
+		Short: "prints the version to stdout",
+		Run: func(cmd *cobra.Command, args []string) {
+			fmt.Println("2015-06-29")
+		},
+	}
+	main.AddCommand(shrug)
+	main.AddCommand(dance)
+	main.AddCommand(version)
+	main.Execute()
 }

src/mcquay.me/yay/term.go

@@ -20,12 +20,15 @@ type ViewPort struct {
 	vcenter      int
 	hcenter      int
 
+	timeout time.Duration
+
 	animation Animation
 }
 
-func NewViewPort(a Animation) *ViewPort {
+func NewViewPort(a Animation, to time.Duration) *ViewPort {
 	vp := &ViewPort{
 		animation: a,
+		timeout:   to,
 	}
 	return vp
 }
@@ -53,7 +56,7 @@ func (tb *ViewPort) Run() {
 
 	func() {
 
-		tick := time.Tick(200 * time.Millisecond)
+		tick := time.Tick(tb.timeout)
 		for {
 			termbox.Clear(termbox.ColorBlack, termbox.ColorBlack)
 			tb.draw()