owncloud / core

		$backend = self::getBackend($itemType);

		$l = \OC::$server->getL10N('lib');

		if ($backend->isShareTypeAllowed($shareType) === false) {

			$message = 'Sharing %s failed, because the backend does not allow shares from type %i';

			$message_t = $l->t('Sharing %s failed, because the backend does not allow shares from type %i', array($itemSourceName, $shareType));

			\OC_Log::write('OCP\Share', sprintf($message, $itemSourceName, $shareType), \OC_Log::ERROR);

			throw new \Exception($message_t);

		}

		$uidOwner = \OC_User::getUser();

		$shareWithinGroupOnly = self::shareWithGroupMembersOnly();

		// Verify share type and sharing conditions are met

		if ($shareType === self::SHARE_TYPE_USER) {

			if ($shareWith == $uidOwner) {

				$message = 'Sharing %s failed, because the user %s is the item owner';

				$message_t = $l->t('Sharing %s failed, because the user %s is the item owner', array($itemSourceName, $shareWith));

				\OC_Log::write('OCP\Share', sprintf($message, $itemSourceName, $shareWith), \OC_Log::ERROR);

				throw new \Exception($message_t);

			}

			if (!\OC_User::userExists($shareWith)) {

				$message = 'Sharing %s failed, because the user %s does not exist';

				$message_t = $l->t('Sharing %s failed, because the user %s does not exist', array($itemSourceName, $shareWith));

				\OC_Log::write('OCP\Share', sprintf($message, $itemSourceName, $shareWith), \OC_Log::ERROR);

				throw new \Exception($message_t);

			}

			if (!\OC_User::userExists($shareWith)) {

				$message = 'Sharing %s failed, because the user %s does not exist';

				$message_t = $l->t('Sharing %s failed, because the user %s does not exist', array($itemSourceName, $shareWith));

				\OC_Log::write('OCP\Share', sprintf($message, $itemSourceName, $shareWith), \OC_Log::ERROR);

				throw new \Exception($message_t);

			}

			if ($shareWithinGroupOnly) {

				$inGroup = array_intersect(\OC_Group::getUserGroups($uidOwner), \OC_Group::getUserGroups($shareWith));

				if (empty($inGroup)) {

			}

			if ($shareWithinGroupOnly) {

				$inGroup = array_intersect(\OC_Group::getUserGroups($uidOwner), \OC_Group::getUserGroups($shareWith));

				if (empty($inGroup)) {

					$message = 'Sharing %s failed, because the user '

						.'%s is not a member of any groups that %s is a member of';

					$message_t = $l->t('Sharing %s failed, because the user %s is not a member of any groups that %s is a member of', array($itemSourceName, $shareWith, $uidOwner));

					\OC_Log::write('OCP\Share', sprintf($message, $itemSourceName, $shareWith, $uidOwner), \OC_Log::ERROR);

					throw new \Exception($message_t);

				}

			}

			// Check if the item source is already shared with the user, either from the same owner or a different user

			if ($checkExists = self::getItems($itemType, $itemSource, self::$shareTypeUserAndGroups,

				}

			}

		} else if ($shareType === self::SHARE_TYPE_GROUP) {

			if (!\OC_Group::groupExists($shareWith)) {

				$message = 'Sharing %s failed, because the group %s does not exist';

				$message_t = $l->t('Sharing %s failed, because the group %s does not exist', array($itemSourceName, $shareWith));

				\OC_Log::write('OCP\Share', sprintf($message, $itemSourceName, $shareWith), \OC_Log::ERROR);

				throw new \Exception($message_t);

			}

			if ($shareWithinGroupOnly && !\OC_Group::inGroup($uidOwner, $shareWith)) {

				$message = 'Sharing %s failed, because '

					.'%s is not a member of the group %s';

			$result['suggestedFileTarget'] = null;

			$result['itemSource'] = $itemSource;

			$result['expirationDate'] = $expirationDate;

			if (!$backend->isValidSource($itemSource, $uidOwner)) {

				$message = 'Sharing %s failed, because the sharing backend for '

					.'%s could not find its source';

				$message_t = $l->t('Sharing %s failed, because the sharing backend for %s could not find its source', array($itemSource, $itemType));

				\OC_Log::write('OCP\Share', sprintf($message, $itemSource, $itemType), \OC_Log::ERROR);

				throw new \Exception($message_t);

			}

			if ($backend instanceof \OCP\Share_Backend_File_Dependent) {

				$result['filePath'] = $backend->getFilePath($itemSource, $uidOwner);

				if ($itemType == 'file' || $itemType == 'folder') {