Send notification mail for circle invitation

lib/Listeners/Notifications/RequestingMember.php

@@ -37,8 +37,10 @@
 use OCA\Circles\Events\RequestingCircleMemberEvent;
 use OCA\Circles\Exceptions\RequestBuilderException;
 use OCA\Circles\Service\NotificationService;
+use OCA\Circles\Service\SendMailService;
 use OCP\EventDispatcher\Event;
 use OCP\EventDispatcher\IEventListener;
+use OCP\IUserManager;
 
 /**
  * Class RequestingMember
@@ -52,12 +54,23 @@ class RequestingMember implements IEventListener {
 	/** @var NotificationService */
 	private $notificationService;
 
+	/** @var SendMailService */
+	private $sendMailService;
+
+	/** @var IUserManager */
+	protected $userManager;
 
 	/**
 	 * RequestingMember constructor.
 	 */
-	public function __construct(NotificationService $notificationService) {
+	public function __construct(
+		NotificationService $notificationService,
+		SendMailService $sendMailService,
+		IUserManager $userManager
+	) {
 		$this->notificationService = $notificationService;
+		$this->sendMailService = $sendMailService;
+		$this->userManager = $userManager;
 
 		$this->setup('app', Application::APP_ID);
 	}
@@ -74,11 +87,28 @@ public function handle(Event $event): void {
 		}
 
 		$member = $event->getMember();
+		$circle = $event->getCircle();
 
 		if ($event->getType() === CircleGenericEvent::REQUESTED) {
 			$this->notificationService->notificationRequested($member);
 		} else {
 			$this->notificationService->notificationInvited($member);
+
+			if ($member->hasInvitedBy()) {
+				$author = $member->getInvitedBy()->getDisplayName();
+			} else {
+				$author = 'someone';
+			}
+			$userId = $member->getUserId();
+			$user = $this->userManager->get($userId);
+			$mails = [$user->getEMailAddress()];
+
+			$this->sendMailService->generateInvitationMail(
+				$author,
+				$circle,
+				$member,
+				$mails
+			);
 		}
 	}
 }

lib/Service/SendMailService.php

@@ -88,6 +88,93 @@ public function __construct(
 	}
 
 
+	/**
+	 * @param string $author
+	 * @param Circle $circle
+	 * @param Member $member
+	 * @param array $mails
+	 */
+	public function generateInvitationMail(
+		string $author,
+		Circle $circle,
+		Member $member,
+		array $mails,
+	): void {
+
+
+		if ($member->getUserType() === Member::TYPE_MAIL) {
+			$mails = [$member->getUserId()];
+		}
+
+		if (empty($mails)) {
+			return;
+		}
+
+		$circleName = $circle->getDisplayName();
+
+		$template = $this->generateMailInvitation(
+			$author,
+			$circleName
+		);
+
+		foreach ($mails as $mail) {
+			try {
+				$this->sendMailInvitation($template, $author, $mail, $circleName);
+			} catch (Exception $e) {
+			}
+		}
+	}
+
+	/**
+	 * @param string $author
+	 * @param string $circleName
+	 *
+	 * @return IEMailTemplate
+	 */
+	private function generateMailInvitation(
+		string $author,
+		string $circleName
+	): IEMailTemplate {
+		$emailTemplate = $this->mailer->createEMailTemplate('circles.ExistingShareNotification', []);
+		$emailTemplate->addHeader();
+
+		$text = $this->l10n->t('%s invited you to the circle %s.', [$author, $circleName]);
+		$emailTemplate->addBodyText(htmlspecialchars($text), $text);
+
+		return $emailTemplate;
+	}
+
+
+	/**
+	 * @param IEMailTemplate $emailTemplate
+	 * @param string $author
+	 * @param string $recipient
+	 * @param string $circleName
+	 *
+	 * @throws Exception
+	 */
+	private function sendMailInvitation(
+		IEMailTemplate $emailTemplate,
+		string $author,
+		string $recipient,
+		string $circleName
+	) {
+		$instanceName = $this->defaults->getName();
+		$senderName = $this->l10n->t('%s on %s', [$author, $instanceName]);
+		$subject = $this->l10n->t('%s invited you to the circle %s.', [$author, $circleName]);
+
+		$message = $this->mailer->createMessage();
+
+		$message->setFrom([Util::getDefaultEmailAddress($instanceName) => $senderName]);
+		$message->setSubject($subject);
+		$message->setPlainBody($emailTemplate->renderText());
+		$message->setHtmlBody($emailTemplate->renderHtml());
+		$message->setTo([$recipient]);
+
+		$this->mailer->send($message);
+	}
+
+
 	/**
 	 * @param string $author
 	 * @param Circle $circle