Only allow locally mounted storage on which the preview system has be…

…en enabled

Fixes #13

service/filesservice.php

@@ -106,17 +106,20 @@ protected function getNodes($folder, $subDepth) {
 	}
 
 	/**
-	 * Determines if the files are hosted locally (shared or not)
+	 * Determines if the files are hosted locally (shared or not) and can be used by the preview
+	 * system
 	 *
-	 * isMounted() includes externally hosted shares, so we need to exclude those
+	 * isMounted() includes externally hosted shares (s2s) and locally mounted shares, so we need
+	 * to exclude those
 	 *
 	 * @param Node $node
 	 *
 	 * @return bool
 	 */
 	protected function isLocalAndAvailable($node) {
 		if (!$node->isMounted()) {
-			return !$this->isExternalShare($node) && $node->isReadable();
+
+			return $this->isLocal($node) && $this->isAvailable($node);
 		}
 
 		return false;
@@ -256,6 +259,33 @@ private function recoverFromGetNodesError($subDepth, $exception) {
 		return [];
 	}
 
+	/**
+	 * Determines if we can consider the node mounted locally or if it's been authorised to be
+	 * scanned
+	 *
+	 * @param Node $node
+	 *
+	 * @return bool
+	 */
+	private function isLocal($node) {
+		$mount = $node->getMountPoint();
+
+		return !$this->isExternalShare($node) && $mount && $mount->getOption('previews', true);
+	}
+
+	/**
+	 * Determines if the node is available, as in readable
+	 *
+	 * @todo Test to see by how much using file_exists slows things down
+	 *
+	 * @param Node $node
+	 *
+	 * @return bool
+	 */
+	private function isAvailable($node) {
+		return $node->isReadable();
+	}
+
 	/**
 	 * Determines if the node is a share which is hosted externally
 	 *