feat(cmd/random/password): Generate password with random case and wit…

…h underscores instead of dashes

cmd/random/password/password.go

@@ -2,6 +2,9 @@ package password
 
 import (
 	"fmt"
+	"log"
+	"strings"
+	"unicode"
 
 	random_cmd "github.com/sikalabs/slu/cmd/random"
 	"github.com/sikalabs/slu/utils/random_utils"
@@ -15,15 +18,60 @@ var Cmd = &cobra.Command{
 	Aliases: []string{"pwd", "passwd", "pass"},
 	Args:    cobra.NoArgs,
 	Run: func(c *cobra.Command, args []string) {
-		fmt.Println(
-			random_utils.RandomString(4, random_utils.LOWER) + "-" +
-				random_utils.RandomString(4, random_utils.UPPER) + "-" +
-				random_utils.RandomString(4, random_utils.DIGITS) + "-" +
-				random_utils.RandomString(4, ""),
-		)
+		i := 0
+		for {
+			s := random_utils.RandomString(16, random_utils.ALL)
+			if containsLowercase(s) && containsUpercase(s) && containsDigit(s) {
+				fmt.Println(addUnderscores(s))
+				break
+			}
+			if i > 20 {
+				log.Fatalln("Cannot generate password")
+			}
+		}
 	},
 }
 
 func init() {
 	random_cmd.Cmd.AddCommand(Cmd)
 }
+
+func containsLowercase(s string) bool {
+	for _, r := range s {
+		if unicode.IsLower(r) {
+			return true
+		}
+	}
+	return false
+}
+
+func containsUpercase(s string) bool {
+	for _, r := range s {
+		if unicode.IsLower(r) {
+			return true
+		}
+	}
+	return false
+}
+
+func containsDigit(s string) bool {
+	for _, r := range s {
+		if unicode.IsDigit(r) {
+			return true
+		}
+	}
+	return false
+}
+
+func addUnderscores(input string) string {
+	var blocks []string
+	for i := 0; i < len(input); i += 4 {
+		end := i + 4
+		if end > len(input) {
+			end = len(input)
+		}
+		blocks = append(blocks, input[i:end])
+	}
+
+	return strings.Join(blocks, "_")
+}