feat: Add UI port for guard

internal/ui/colors.go

@@ -0,0 +1,17 @@
+package ui
+
+import "github.com/fatih/color"
+
+type TerminalColors struct {
+	Red    func(format string, a ...interface{}) string
+	Yellow func(format string, a ...interface{}) string
+	Cyan   func(format string, a ...interface{}) string
+	Green  func(format string, a ...interface{}) string
+}
+
+var Colors = TerminalColors{
+	Red:    color.New(color.FgRed, color.Bold).SprintfFunc(),
+	Yellow: color.New(color.FgYellow).SprintfFunc(),
+	Cyan:   color.New(color.FgCyan).SprintfFunc(),
+	Green:  color.New(color.FgGreen).SprintfFunc(),
+}

internal/ui/spinner.go

@@ -0,0 +1,45 @@
+package ui
+
+import (
+	"fmt"
+	"time"
+)
+
+var spinnerChan chan bool
+
+func StartSpinner(msg string) {
+	style := `⠋⠙⠹⠸⠼⠴⠦⠧⠇⠏`
+	frames := []rune(style)
+	length := len(frames)
+
+	spinnerChan = make(chan bool)
+
+	ticker := time.NewTicker(100 * time.Millisecond)
+	go func() {
+		pos := 0
+
+		for {
+			select {
+			case <-spinnerChan:
+				ticker.Stop()
+				return
+			case <-ticker.C:
+				fmt.Printf("\r%s ... %s", msg, string(frames[pos%length]))
+				pos += 1
+			}
+		}
+	}()
+}
+
+func StopSpinner() {
+	// Gracefully handle the case where the spinner is already stopped
+	// and the channel is closed, yet client code calls StopSpinner() again.
+	defer func() {
+		_ = recover()
+	}()
+
+	close(spinnerChan)
+
+	fmt.Printf("\r")
+	fmt.Println()
+}

internal/ui/ui.go

@@ -0,0 +1,87 @@
+package ui
+
+import (
+	"fmt"
+	"os"
+	"strings"
+
+	packagev1 "buf.build/gen/go/safedep/api/protocolbuffers/go/safedep/messages/package/v1"
+)
+
+// The UI is internal to PMG and opinionated for the CLI.
+// It is not intended to be used outside of PMG.
+
+type VerbosityLevel int
+
+const (
+	// PMG is hidden from the user except for errors
+	// and when malicious packages are detected
+	VerbosityLevelSilent VerbosityLevel = iota
+
+	// Show minimal status updates
+	VerbosityLevelNormal
+
+	// Show verbose status updates and information including
+	// information about malicious packages
+	VerbosityLevelVerbose
+)
+
+var verbosityLevel VerbosityLevel = VerbosityLevelNormal
+
+func SetVerbosityLevel(level VerbosityLevel) {
+	verbosityLevel = level
+}
+
+func ClearStatus() {
+	StopSpinner()
+	fmt.Print("\r")
+}
+
+func Block() error {
+	StopSpinner()
+
+	fmt.Println(Colors.Red("❌ Malicious packages detected, installation blocked!"))
+	os.Exit(1)
+
+	return nil
+}
+
+func SetStatus(status string) {
+	if verbosityLevel == VerbosityLevelSilent {
+		return
+	}
+
+	StopSpinner()
+
+	fmt.Print("\r", Colors.Green(status), " ")
+	StartSpinner(status)
+}
+
+func GetConfirmationOnMalware(malwarePackages []*packagev1.PackageVersion) (bool, error) {
+	StopSpinner()
+	fmt.Println(Colors.Red("🚨 Malicious packages detected:"))
+
+	for _, pkg := range malwarePackages {
+		fmt.Println("  ⚠️ ", Colors.Red(fmt.Sprintf("%s@%s", pkg.Package.Name, pkg.Version)))
+	}
+
+	fmt.Println()
+	fmt.Print(Colors.Yellow("Do you want to continue with the installation? (y/N) "))
+
+	var response string
+
+	// We don't care about the error here because we will return false
+	// if the user doesn't provide a valid response
+	_, _ = fmt.Scanln(&response)
+
+	if len(response) == 0 {
+		return false, nil
+	}
+
+	response = strings.ToLower(response)
+	if response == "y" || response == "yes" || response[0] == 'y' {
+		return true, nil
+	}
+
+	return false, nil
+}