func modifyConfig()

in pkg/cmd/config/set.go [144:262]
96 lines of code
30 McCabe index (conditional complexity)

func modifyConfig(curr reflect.Value, steps *navigationSteps, propertyValue string, unset bool, setRawBytes bool) error {
	currStep := steps.pop()

	actualCurrValue := curr
	if curr.Kind() == reflect.Ptr {
		actualCurrValue = curr.Elem()
	}

	switch actualCurrValue.Kind() {
	case reflect.Map:
		if !steps.moreStepsRemaining() && !unset {
			return fmt.Errorf("can't set a map to a value: %v", actualCurrValue)
		}

		mapKey := reflect.ValueOf(currStep.stepValue)
		mapValueType := curr.Type().Elem().Elem()

		if !steps.moreStepsRemaining() && unset {
			actualCurrValue.SetMapIndex(mapKey, reflect.Value{})
			return nil
		}

		currMapValue := actualCurrValue.MapIndex(mapKey)

		needToSetNewMapValue := currMapValue.Kind() == reflect.Invalid
		if needToSetNewMapValue {
			if unset {
				return fmt.Errorf("current map key `%v` is invalid", mapKey.Interface())
			}
			currMapValue = reflect.New(mapValueType.Elem()).Elem().Addr()
			actualCurrValue.SetMapIndex(mapKey, currMapValue)
		}

		err := modifyConfig(currMapValue, steps, propertyValue, unset, setRawBytes)
		if err != nil {
			return err
		}

		return nil

	case reflect.String:
		if steps.moreStepsRemaining() {
			return fmt.Errorf("can't have more steps after a string. %v", steps)
		}
		actualCurrValue.SetString(propertyValue)
		return nil

	case reflect.Slice:
		if steps.moreStepsRemaining() {
			return fmt.Errorf("can't have more steps after bytes. %v", steps)
		}
		innerKind := actualCurrValue.Type().Elem().Kind()
		if innerKind != reflect.Uint8 {
			return fmt.Errorf("unrecognized slice type. %v", innerKind)
		}

		if unset {
			actualCurrValue.Set(reflect.Zero(actualCurrValue.Type()))
			return nil
		}

		if setRawBytes {
			actualCurrValue.SetBytes([]byte(propertyValue))
		} else {
			val, err := base64.StdEncoding.DecodeString(propertyValue)
			if err != nil {
				return fmt.Errorf("error decoding input value: %v", err)
			}
			actualCurrValue.SetBytes(val)
		}
		return nil

	case reflect.Bool:
		if steps.moreStepsRemaining() {
			return fmt.Errorf("can't have more steps after a bool. %v", steps)
		}
		boolValue, err := toBool(propertyValue)
		if err != nil {
			return err
		}
		actualCurrValue.SetBool(boolValue)
		return nil

	case reflect.Struct:
		for fieldIndex := 0; fieldIndex < actualCurrValue.NumField(); fieldIndex++ {
			currFieldValue := actualCurrValue.Field(fieldIndex)
			currFieldType := actualCurrValue.Type().Field(fieldIndex)
			currYamlTag := currFieldType.Tag.Get("json")
			currFieldTypeYamlName := strings.Split(currYamlTag, ",")[0]

			if currFieldTypeYamlName == currStep.stepValue {
				thisMapHasNoValue := (currFieldValue.Kind() == reflect.Map && currFieldValue.IsNil())

				if thisMapHasNoValue {
					newValue := reflect.MakeMap(currFieldValue.Type())
					currFieldValue.Set(newValue)

					if !steps.moreStepsRemaining() && unset {
						return nil
					}
				}

				if !steps.moreStepsRemaining() && unset {
					// if we're supposed to unset the value or if the value is a map that doesn't exist, create a new value and overwrite
					newValue := reflect.New(currFieldValue.Type()).Elem()
					currFieldValue.Set(newValue)
					return nil
				}

				return modifyConfig(currFieldValue.Addr(), steps, propertyValue, unset, setRawBytes)
			}
		}

		return fmt.Errorf("unable to locate path %#v under %v", currStep, actualCurrValue)

	}

	panic(fmt.Errorf("unrecognized type: %v", actualCurrValue))
}