backend added struct merging and FieldPermissionsOnRoleId

internal/utils/priviliges.go

@@ -3,6 +3,9 @@ package utils
 import (
 	"GoMembership/internal/constants"
 	"GoMembership/internal/models"
+	"GoMembership/pkg/logger"
+	"errors"
+	"reflect"
 )
 
 func HasPrivilige(user *models.User, privilige int8) bool {
@@ -18,5 +21,126 @@ func HasPrivilige(user *models.User, privilige int8) bool {
 	default:
 		return false
 	}
-
+}
+
+// FilterAllowedStructFields filters allowed fields recursively in a struct and modifies structToModify in place.
+func FilterAllowedStructFields(input interface{}, existing interface{}, allowedFields map[string]bool, prefix string) error {
+	v := reflect.ValueOf(input)
+	origin := reflect.ValueOf(existing)
+
+	// Ensure both input and target are pointers to structs
+	if v.Kind() != reflect.Ptr || origin.Kind() != reflect.Ptr {
+		return errors.New("both input and existing must be pointers to structs")
+	}
+
+	v = v.Elem()
+	origin = origin.Elem()
+
+	if v.Kind() != reflect.Struct || origin.Kind() != reflect.Struct {
+		return errors.New("both input and existing must be structs")
+	}
+
+	for i := 0; i < v.NumField(); i++ {
+		field := v.Type().Field(i)
+		key := field.Name
+
+		// Skip unexported fields
+		if !field.IsExported() {
+			continue
+		}
+
+		// Build the full field path
+		fullKey := key
+		if prefix != "" {
+			fullKey = prefix + "." + key
+		}
+		fieldValue := v.Field(i)
+		originField := origin.Field(i)
+
+		// Handle nil pointers
+		if fieldValue.Kind() == reflect.Ptr {
+			if fieldValue.IsNil() {
+				// If the field is nil, skip it or initialize it
+				if !allowedFields[fullKey] {
+					// If the field is not allowed, set it to the corresponding field from existing
+					fieldValue.Set(originField)
+				}
+				continue
+			}
+			// Dereference the pointer for further processing
+			fieldValue = fieldValue.Elem()
+			originField = originField.Elem()
+		}
+
+		// Handle slices
+		if fieldValue.Kind() == reflect.Slice {
+			if !allowedFields[fullKey] {
+				// If the slice is not allowed, set it to the corresponding slice from existing
+				fieldValue.Set(originField)
+				continue
+			} else {
+				originField.Set(fieldValue)
+			}
+
+			// If the slice contains structs, recursively filter each element
+			// if fieldValue.Type().Elem().Kind() == reflect.Struct {
+			// 	for j := 0; j < fieldValue.Len(); j++ {
+			// 		err := FilterAllowedStructFields(
+			// 			fieldValue.Index(j).Addr().Interface(),
+			// 			originField.Index(j).Addr().Interface(),
+			// 			allowedFields,
+			// 			fullKey,
+			// 		)
+			// 		if err != nil {
+			// 			return err
+			// 		}
+			// 	}
+			// }
+			continue
+		}
+
+		// Handle nested structs (including pointers to structs)
+		if fieldValue.Kind() == reflect.Struct || (fieldValue.Kind() == reflect.Ptr && fieldValue.Type().Elem().Kind() == reflect.Struct) {
+			if fieldValue.Kind() == reflect.Ptr {
+				if fieldValue.IsNil() {
+					continue
+				}
+				fieldValue = fieldValue.Elem()
+				originField = originField.Elem() // May result in an invalid originField
+			}
+
+			var originCopy reflect.Value
+
+			// Check if originField is valid (non-zero)
+			if originField.IsValid() {
+				originCopy = reflect.New(originField.Type()).Elem()
+				originCopy.Set(originField)
+			} else {
+				// If originField is invalid (e.g., existing had a nil pointer),
+				// create a new instance of the type from fieldValue
+				originCopy = reflect.New(fieldValue.Type()).Elem()
+			}
+
+			err := FilterAllowedStructFields(
+				fieldValue.Addr().Interface(),
+				originCopy.Addr().Interface(),
+				allowedFields,
+				fullKey,
+			)
+			if err != nil {
+				return err
+			}
+			continue
+		}
+
+		// Only allow whitelisted fields
+		if !allowedFields[fullKey] {
+			logger.Error.Printf("denying update of field: %#v", fullKey)
+			fieldValue.Set(originField)
+		} else {
+			logger.Error.Printf("updating whitelisted field: %#v", fullKey)
+		}
+
+	}
+	return nil
 }