Update

internal/validator/validator_helpers.go

@@ -1,6 +1,12 @@
 package validator
 
-import "regexp"
+import (
+	"errors"
+	"regexp"
+	"strings"
+
+	"github.com/go-playground/validator/v10"
+)
 
 // Shared helper functions for validators
 func isValidEmail(email string) bool {
@@ -30,3 +36,27 @@ func isValidPlanType(planType string) bool {
 	}
 	return validPlanTypes[planType]
 }
+
+func formatValidationError(err error) error {
+	if validationErrors, ok := err.(validator.ValidationErrors); ok {
+		var errorMessages []string
+		for _, fieldError := range validationErrors {
+			switch fieldError.Tag() {
+			case "required":
+				errorMessages = append(errorMessages, fieldError.Field()+" is required")
+			case "email":
+				errorMessages = append(errorMessages, fieldError.Field()+" must be a valid email")
+			case "min":
+				errorMessages = append(errorMessages, fieldError.Field()+" must be at least "+fieldError.Param())
+			case "max":
+				errorMessages = append(errorMessages, fieldError.Field()+" must be at most "+fieldError.Param())
+			case "oneof":
+				errorMessages = append(errorMessages, fieldError.Field()+" must be one of: "+fieldError.Param())
+			default:
+				errorMessages = append(errorMessages, fieldError.Field()+" is invalid")
+			}
+		}
+		return errors.New(strings.Join(errorMessages, "; "))
+	}
+	return err
+}