refactor check for valid yob

internal/handlers/ussd/menuhandler.go

@@ -154,7 +154,7 @@ func (h *Handlers) SetLanguage(ctx context.Context, sym string, input []byte) (r
 	code := strings.Split(symbol, "_")[1]
 
 	if !utils.IsValidISO639(code) {
-		//Fallback to english instead? 
+		//Fallback to english instead?
 		code = "eng"
 	}
 	res.FlagSet = append(res.FlagSet, state.FLAG_LANG)
@@ -764,12 +764,11 @@ func (h *Handlers) VerifyYob(ctx context.Context, sym string, input []byte) (res
 		return res, nil
 	}
 
-	if len(date) == 4 {
+	if utils.IsValidYOb(date) {
 		res.FlagReset = append(res.FlagReset, flag_incorrect_date_format)
 	} else {
 		res.FlagSet = append(res.FlagSet, flag_incorrect_date_format)
 	}
-
 	return res, nil
 }
 

internal/utils/age.go

@@ -1,6 +1,9 @@
 package utils
 
-import "time"
+import (
+	"strconv"
+	"time"
+)
 
 // CalculateAge calculates the age based on a given birthdate and the current date in the format dd/mm/yy
 // It adjusts for cases where the current date is before the birthday in the current year.
@@ -25,11 +28,29 @@ func CalculateAge(birthdate, today time.Time) int {
 // It subtracts the YOB from the current year to determine the age.
 //
 // Parameters:
-//   yob: The year of birth as an integer.
+//
+//	yob: The year of birth as an integer.
 //
 // Returns:
-//   The calculated age as an integer.
+//
+//	The calculated age as an integer.
 func CalculateAgeWithYOB(yob int) int {
-    currentYear := time.Now().Year()
-    return currentYear - yob
-}
+	currentYear := time.Now().Year()
+	return currentYear - yob
+}
+
+
+//IsValidYob checks if the provided yob can be considered valid 
+func IsValidYOb(yob string) bool {
+	currentYear := time.Now().Year()
+	yearOfBirth, err := strconv.ParseInt(yob, 10, 64)
+	if err != nil {
+		return false
+	}
+	if yearOfBirth >= 1900 && int(yearOfBirth) <= currentYear {
+		return true
+	} else {
+		return false
+	}
+
+}