public function replacePlaceholdersInStartedOnlineMail(ClientSurvey $client_survey, EmailType $type, string $template, string $lang): array|string 	{ 		$email_template = __('email-templates.survey-started-online-mail-default-template-with-placeholders'); 		$survey_email_template = $client_survey->emailTemplates()->where('type', $type->value)->first();  		if ($survey_email_template) { 			return $template; 		}  		$date = $this->getSurveyStartDate($client_survey); 		$template_part_two_optional = str_replace(':date', $date, __('email-templates.survey-started-online-mail-default-template-part-two-optional', [], $lang)); 		$email_template = str_replace(':part_two_optional', $template_part_two_optional, $email_template);  		$applicants_exists = $client_survey->applicants()->whereNotNull('email')->where(function ($query) { 			$query->where('invitation_sent', false)->orWhere('reminder_sent', false); 		})->count();  		if ($applicants_exists) { 			$email_template = str_replace(':part_three_optional', __('email-templates.survey-started-online-mail-default-template-part-three-optional', [], $lang), $email_template); 		}  		return $email_template; 	}