package gvalid

// getErrorMessageByRule retrieves and returns the error message for specified rule.
// It firstly retrieves the message from custom message map, and then checks i18n manager,
// it returns the default error message if it's not found in custom message map or i18n manager.
func (v *Validator) getErrorMessageByRule(ruleKey string, customMsgMap map[string]string) string {
	content := customMsgMap[ruleKey]
	if content != "" {
		// I18n translation.
		i18nContent := v.i18nManager.GetContent(v.ctx, content)
		if i18nContent != "" {
			return i18nContent
		}
		return content
	}
	// Retrieve default message according to certain rule.
	content = v.i18nManager.GetContent(v.ctx, ruleMessagePrefixForI18n+ruleKey)
	if content == "" {
		content = defaultMessages[ruleKey]
	}
	// If there's no configured rule message, it uses default one.
	if content == "" {
		content = v.i18nManager.GetContent(v.ctx, ruleMessagePrefixForI18n+internalDefaultRuleName)
		if content == "" {
			content = defaultMessages[internalDefaultRuleName]
		}
	}
	return content
}