feat: notify when a new version is available

cmd/root.go

@@ -1,11 +1,75 @@
 package cmd
 
 import (
+	"context"
+	"fmt"
+	"os"
+	"slices"
+
+	"github.com/mathismqn/godeez/internal/buildinfo"
+	"github.com/mathismqn/godeez/internal/updater"
 	"github.com/spf13/cobra"
+	"golang.org/x/term"
 )
 
+const updateNoticeAnnotation = "godeez:update-notice"
+
 var RootCmd = &cobra.Command{
 	Use:          "godeez",
 	Short:        "GoDeez is a tool to download music from Deezer",
 	SilenceUsage: true,
 }
+
+func Execute(ctx context.Context) error {
+	var notice <-chan string
+	if wantsUpdateNotice() {
+		notice = updater.StartCheck(ctx)
+	}
+
+	err := RootCmd.ExecuteContext(ctx)
+
+	printUpdateNotice(notice)
+
+	return err
+}
+
+func wantsUpdateNotice() bool {
+	if !term.IsTerminal(int(os.Stderr.Fd())) {
+		return false
+	}
+
+	args := os.Args[1:]
+	if slices.Contains(args, "-h") || slices.Contains(args, "--help") {
+		return false
+	}
+
+	target, _, err := RootCmd.Find(args)
+	if err != nil || target == nil {
+		return false
+	}
+
+	if target.Run == nil && target.RunE == nil {
+		return false
+	}
+
+	for cmd := target; cmd != nil; cmd = cmd.Parent() {
+		if cmd.Annotations[updateNoticeAnnotation] == "true" {
+			return true
+		}
+	}
+
+	return false
+}
+
+func printUpdateNotice(notice <-chan string) {
+	select {
+	case latest := <-notice:
+		if latest == "" {
+			return
+		}
+
+		fmt.Fprintf(os.Stderr, "\n  ┌ Update available: %s → %s\n  └ Run `godeez update` to install\n",
+			buildinfo.Version(), latest)
+	default:
+	}
+}