diff --git a/apps/files_sharing/lib/Controller/PublicPreviewController.php b/apps/files_sharing/lib/Controller/PublicPreviewController.php
index 0c8a2c36c3..b91b84c9c3 100644
--- a/apps/files_sharing/lib/Controller/PublicPreviewController.php
+++ b/apps/files_sharing/lib/Controller/PublicPreviewController.php
@@ -22,7 +22,6 @@
  */
 namespace OCA\Files_Sharing\Controller;
 
-use OC\PreviewManager;
 use OCP\AppFramework\Controller;
 use OCP\AppFramework\Http;
 use OCP\AppFramework\Http\DataResponse;
@@ -30,6 +29,7 @@ use OCP\AppFramework\Http\FileDisplayResponse;
 use OCP\Constants;
 use OCP\Files\Folder;
 use OCP\Files\NotFoundException;
+use OCP\IPreview;
 use OCP\IRequest;
 use OCP\Share\Exceptions\ShareNotFound;
 use OCP\Share\IManager as ShareManager;
@@ -39,13 +39,13 @@ class PublicPreviewController extends Controller {
 	/** @var ShareManager */
 	private $shareManager;
 
-	/** @var PreviewManager */
+	/** @var IPreview */
 	private $previewManager;
 
 	public function __construct($appName,
 								IRequest $request,
 								ShareManager $shareManger,
-								PreviewManager $previewManager) {
+								IPreview $previewManager) {
 		parent::__construct($appName, $request);
 
 		$this->shareManager = $shareManger;
@@ -71,11 +71,7 @@ class PublicPreviewController extends Controller {
 		$a = false
 	) {
 
-		if ($t === '') {
-			return new DataResponse([], Http::STATUS_BAD_REQUEST);
-		}
-
-		if ($x === 0 || $y === 0) {
+		if ($t === '' || $x === 0 || $y === 0) {
 			return new DataResponse([], Http::STATUS_BAD_REQUEST);
 		}
 
@@ -89,20 +85,18 @@ class PublicPreviewController extends Controller {
 			return new DataResponse([], Http::STATUS_FORBIDDEN);
 		}
 
-		$node = $share->getNode();
-
-		if ($node instanceof Folder) {
-			try {
+		try {
+			$node = $share->getNode();
+			if ($node instanceof Folder) {
 				$file = $node->get($file);
-			} catch (NotFoundException $e) {
-				return new DataResponse([], Http::STATUS_NOT_FOUND);
+			} else {
+				$file = $node;
 			}
-		} else {
-			$file = $node;
+
+			$f = $this->previewManager->getPreview($file, $x, $y, !$a);
+			return new FileDisplayResponse($f, Http::STATUS_OK, ['Content-Type' => $f->getMimeType()]);
+		} catch (NotFoundException $e) {
+			return new DataResponse([], Http::STATUS_NOT_FOUND);
 		}
-
-		$f = $this->previewManager->getPreview($file, $x, $y, !$a);
-
-		return new FileDisplayResponse($f, Http::STATUS_OK, ['Content-Type' => $f->getMimeType()]);
 	}
 }
diff --git a/apps/files_sharing/tests/Controller/PublicPreviewControllerTest.php b/apps/files_sharing/tests/Controller/PublicPreviewControllerTest.php
new file mode 100644
index 0000000000..174abbb6f6
--- /dev/null
+++ b/apps/files_sharing/tests/Controller/PublicPreviewControllerTest.php
@@ -0,0 +1,193 @@
+<?php
+/**
+ * @copyright Copyright (c) 2016, Roeland Jago Douma <roeland@famdouma.nl>
+ *
+ * @author Roeland Jago Douma <roeland@famdouma.nl>
+ *
+ * @license GNU AGPL version 3 or any later version
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as
+ * published by the Free Software Foundation, either version 3 of the
+ * License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ *
+ */
+namespace OCA\Files_Sharing\Tests\Controller;
+
+use OCA\Files_Sharing\Controller\PublicPreviewController;
+use OCP\AppFramework\Http;
+use OCP\AppFramework\Http\DataResponse;
+use OCP\AppFramework\Http\FileDisplayResponse;
+use OCP\Constants;
+use OCP\Files\File;
+use OCP\Files\Folder;
+use OCP\Files\NotFoundException;
+use OCP\Files\SimpleFS\ISimpleFile;
+use OCP\IPreview;
+use OCP\IRequest;
+use OCP\Share\Exceptions\ShareNotFound;
+use OCP\Share\IManager;
+use OCP\Share\IShare;
+use Punic\Data;
+use Test\TestCase;
+
+class PublicPreviewControllerTest extends TestCase {
+
+	/** @var IPreview|\PHPUnit_Framework_MockObject_MockObject */
+	private $previewManager;
+
+	/** @var IManager|\PHPUnit_Framework_MockObject_MockObject */
+	private $shareManager;
+
+	/** @var PublicPreviewController */
+	private $controller;
+
+	public function setUp() {
+		parent::setUp();
+
+		$this->previewManager = $this->createMock(IPreview::class);
+		$this->shareManager = $this->createMock(IManager::class);
+
+		$this->controller = new PublicPreviewController(
+			'files_sharing',
+			$this->createMock(IRequest::class),
+			$this->shareManager,
+			$this->previewManager
+		);
+	}
+
+	public function testInvalidToken() {
+		$res = $this->controller->getPreview('file', 10, 10, '');
+		$expected = new DataResponse([], Http::STATUS_BAD_REQUEST);
+
+		$this->assertEquals($expected, $res);
+	}
+
+	public function testInvalidWidth() {
+		$res = $this->controller->getPreview('file', 0);
+		$expected = new DataResponse([], Http::STATUS_BAD_REQUEST);
+
+		$this->assertEquals($expected, $res);
+	}
+
+	public function testInvalidHeight() {
+		$res = $this->controller->getPreview('file', 10, 0);
+		$expected = new DataResponse([], Http::STATUS_BAD_REQUEST);
+
+		$this->assertEquals($expected, $res);
+	}
+
+	public function testInvalidShare() {
+		$this->shareManager->method('getShareByToken')
+			->with($this->equalTo('token'))
+			->willThrowException(new ShareNotFound());
+
+		$res = $this->controller->getPreview('file', 10, 10, 'token');
+		$expected = new DataResponse([], Http::STATUS_NOT_FOUND);
+
+		$this->assertEquals($expected, $res);
+	}
+
+	public function testShareNotAccessable() {
+		$share = $this->createMock(IShare::class);
+		$this->shareManager->method('getShareByToken')
+			->with($this->equalTo('token'))
+			->willReturn($share);
+
+		$share->method('getPermissions')
+			->willReturn(0);
+
+		$res = $this->controller->getPreview('file', 10, 10, 'token');
+		$expected = new DataResponse([], Http::STATUS_FORBIDDEN);
+
+		$this->assertEquals($expected, $res);
+	}
+
+	public function testPreviewFile() {
+		$share = $this->createMock(IShare::class);
+		$this->shareManager->method('getShareByToken')
+			->with($this->equalTo('token'))
+			->willReturn($share);
+
+		$share->method('getPermissions')
+			->willReturn(Constants::PERMISSION_READ);
+
+		$file = $this->createMock(File::class);
+		$share->method('getNode')
+			->willReturn($file);
+
+		$preview = $this->createMock(ISimpleFile::class);
+		$this->previewManager->method('getPreview')
+			->with($this->equalTo($file), 10, 10, false)
+			->willReturn($preview);
+
+		$preview->method('getMimeType')
+			->willReturn('myMime');
+
+		$res = $this->controller->getPreview('file', 10, 10, 'token', true);
+		$expected = new FileDisplayResponse($preview, Http::STATUS_OK, ['Content-Type' => 'myMime']);
+		$this->assertEquals($expected, $res);
+	}
+
+	public function testPreviewFolderInvalidFile() {
+		$share = $this->createMock(IShare::class);
+		$this->shareManager->method('getShareByToken')
+			->with($this->equalTo('token'))
+			->willReturn($share);
+
+		$share->method('getPermissions')
+			->willReturn(Constants::PERMISSION_READ);
+
+		$folder = $this->createMock(Folder::class);
+		$share->method('getNode')
+			->willReturn($folder);
+
+		$folder->method('get')
+			->with($this->equalTo('file'))
+			->willThrowException(new NotFoundException());
+
+		$res = $this->controller->getPreview('file', 10, 10, 'token', true);
+		$expected = new DataResponse([], Http::STATUS_NOT_FOUND);
+		$this->assertEquals($expected, $res);
+	}
+
+
+	public function testPreviewFolderValidFile() {
+		$share = $this->createMock(IShare::class);
+		$this->shareManager->method('getShareByToken')
+			->with($this->equalTo('token'))
+			->willReturn($share);
+
+		$share->method('getPermissions')
+			->willReturn(Constants::PERMISSION_READ);
+
+		$folder = $this->createMock(Folder::class);
+		$share->method('getNode')
+			->willReturn($folder);
+
+		$file = $this->createMock(File::class);
+		$folder->method('get')
+			->with($this->equalTo('file'))
+			->willReturn($file);
+
+		$preview = $this->createMock(ISimpleFile::class);
+		$this->previewManager->method('getPreview')
+			->with($this->equalTo($file), 10, 10, false)
+			->willReturn($preview);
+
+		$preview->method('getMimeType')
+			->willReturn('myMime');
+
+		$res = $this->controller->getPreview('file', 10, 10, 'token', true);
+		$expected = new FileDisplayResponse($preview, Http::STATUS_OK, ['Content-Type' => 'myMime']);
+		$this->assertEquals($expected, $res);
+	}
+}
diff --git a/apps/files_trashbin/lib/Controller/PreviewController.php b/apps/files_trashbin/lib/Controller/PreviewController.php
index 1e1f68e431..c73b1c17c1 100644
--- a/apps/files_trashbin/lib/Controller/PreviewController.php
+++ b/apps/files_trashbin/lib/Controller/PreviewController.php
@@ -114,11 +114,6 @@ class PreviewController extends Controller {
 			return new Http\FileDisplayResponse($f, Http::STATUS_OK, ['Content-Type' => $f->getMimeType()]);
 		} catch (NotFoundException $e) {
 			return new DataResponse([], Http::STATUS_NOT_FOUND);
-		} catch (\OC\PreviewNotAvailableException $e) {
-			return new DataResponse([], Http::STATUS_NOT_FOUND);
-		}catch(\Exception $e) {
-			return new DataResponse([], Http::STATUS_INTERNAL_SERVER_ERROR);
 		}
-
 	}
 }
diff --git a/apps/files_trashbin/tests/Controller/PreviewControllerTest.php b/apps/files_trashbin/tests/Controller/PreviewControllerTest.php
new file mode 100644
index 0000000000..685e4cebfd
--- /dev/null
+++ b/apps/files_trashbin/tests/Controller/PreviewControllerTest.php
@@ -0,0 +1,181 @@
+<?php
+/**
+ * @copyright Copyright (c) 2016, Roeland Jago Douma <roeland@famdouma.nl>
+ *
+ * @author Roeland Jago Douma <roeland@famdouma.nl>
+ *
+ * @license GNU AGPL version 3 or any later version
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as
+ * published by the Free Software Foundation, either version 3 of the
+ * License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ *
+ */
+namespace OCA\Files_Trashbin\Tests\Controller;
+
+use OCA\Files_Trashbin\Controller\PreviewController;
+use OCP\AppFramework\Http;
+use OCP\AppFramework\Http\DataResponse;
+use OCP\AppFramework\Http\FileDisplayResponse;
+use OCP\Files\File;
+use OCP\Files\Folder;
+use OCP\Files\IMimeTypeDetector;
+use OCP\Files\IRootFolder;
+use OCP\Files\NotFoundException;
+use OCP\Files\SimpleFS\ISimpleFile;
+use OCP\IPreview;
+use OCP\IRequest;
+use Test\TestCase;
+
+class PreviewControllerTest extends TestCase {
+
+	/** @var IRootFolder|\PHPUnit_Framework_MockObject_MockObject */
+	private $rootFolder;
+
+	/** @var string */
+	private $userId;
+
+	/** @var IMimeTypeDetector|\PHPUnit_Framework_MockObject_MockObject */
+	private $mimeTypeDetector;
+
+	/** @var IPreview|\PHPUnit_Framework_MockObject_MockObject */
+	private $previewManager;
+
+	/** @var PreviewController */
+	private $controller;
+
+	public function setUp() {
+		parent::setUp();
+
+		$this->rootFolder = $this->createMock(IRootFolder::class);
+		$this->userId = 'user';
+		$this->mimeTypeDetector = $this->createMock(IMimeTypeDetector::class);
+		$this->previewManager = $this->createMock(IPreview::class);
+
+		$this->controller = new PreviewController(
+			'files_versions',
+			$this->createMock(IRequest::class),
+			$this->rootFolder,
+			$this->userId,
+			$this->mimeTypeDetector,
+			$this->previewManager
+		);
+	}
+
+	public function testInvalidFile() {
+		$res = $this->controller->getPreview('');
+		$expected = new DataResponse([], Http::STATUS_BAD_REQUEST);
+
+		$this->assertEquals($expected, $res);
+	}
+
+	public function testInvalidWidth() {
+		$res = $this->controller->getPreview('file', 0);
+		$expected = new DataResponse([], Http::STATUS_BAD_REQUEST);
+
+		$this->assertEquals($expected, $res);
+	}
+
+	public function testInvalidHeight() {
+		$res = $this->controller->getPreview('file', 10, 0);
+		$expected = new DataResponse([], Http::STATUS_BAD_REQUEST);
+
+		$this->assertEquals($expected, $res);
+	}
+
+	public function testValidPreview() {
+		$userFolder = $this->createMock(Folder::class);
+		$userRoot = $this->createMock(Folder::class);
+		$trash = $this->createMock(Folder::class);
+
+		$this->rootFolder->method('getUserFolder')
+			->with($this->userId)
+			->willReturn($userFolder);
+		$userFolder->method('getParent')
+			->willReturn($userRoot);
+		$userRoot->method('get')
+			->with('files_trashbin/files')
+			->willReturn($trash);
+
+		$this->mimeTypeDetector->method('detectPath')
+			->with($this->equalTo('file'))
+			->willReturn('myMime');
+
+		$file = $this->createMock(File::class);
+		$trash->method('get')
+			->with($this->equalTo('file.1234'))
+			->willReturn($file);
+		$file->method('getName')
+			->willReturn('file.1234');
+
+		$preview = $this->createMock(ISimpleFile::class);
+		$this->previewManager->method('getPreview')
+			->with($this->equalTo($file), 10, 10, true, IPreview::MODE_FILL, 'myMime')
+			->willReturn($preview);
+		$preview->method('getMimeType')
+			->willReturn('previewMime');
+
+		$res = $this->controller->getPreview('file.1234', 10, 10);
+		$expected = new FileDisplayResponse($preview, Http::STATUS_OK, ['Content-Type' => 'previewMime']);
+
+		$this->assertEquals($expected, $res);
+	}
+
+	public function testTrashFileNotFound() {
+		$userFolder = $this->createMock(Folder::class);
+		$userRoot = $this->createMock(Folder::class);
+		$trash = $this->createMock(Folder::class);
+
+		$this->rootFolder->method('getUserFolder')
+			->with($this->userId)
+			->willReturn($userFolder);
+		$userFolder->method('getParent')
+			->willReturn($userRoot);
+		$userRoot->method('get')
+			->with('files_trashbin/files')
+			->willReturn($trash);
+
+		$trash->method('get')
+			->with($this->equalTo('file.1234'))
+			->willThrowException(new NotFoundException());
+
+		$res = $this->controller->getPreview('file.1234', 10, 10);
+		$expected = new DataResponse([], Http::STATUS_NOT_FOUND);
+
+		$this->assertEquals($expected, $res);
+	}
+
+	public function testTrashFolder() {
+		$userFolder = $this->createMock(Folder::class);
+		$userRoot = $this->createMock(Folder::class);
+		$trash = $this->createMock(Folder::class);
+
+		$this->rootFolder->method('getUserFolder')
+			->with($this->userId)
+			->willReturn($userFolder);
+		$userFolder->method('getParent')
+			->willReturn($userRoot);
+		$userRoot->method('get')
+			->with('files_trashbin/files')
+			->willReturn($trash);
+
+		$folder = $this->createMock(Folder::class);
+		$trash->method('get')
+			->with($this->equalTo('folder'))
+			->willReturn($folder);
+
+		$res = $this->controller->getPreview('folder', 10, 10);
+		$expected = new DataResponse([], Http::STATUS_BAD_REQUEST);
+
+		$this->assertEquals($expected, $res);
+	}
+}
diff --git a/apps/files_versions/lib/Controller/PreviewController.php b/apps/files_versions/lib/Controller/PreviewController.php
index 3225febfcf..8d961f47ee 100644
--- a/apps/files_versions/lib/Controller/PreviewController.php
+++ b/apps/files_versions/lib/Controller/PreviewController.php
@@ -78,11 +78,7 @@ class PreviewController extends Controller {
 		$y = 44,
 		$version = ''
 	) {
-		if($file === '' && $version === '') {
-			return new DataResponse([], Http::STATUS_BAD_REQUEST);
-		}
-
-		if($x === 0 || $y === 0) {
+		if($file === '' || $version === '' || $x === 0 || $y === 0) {
 			return new DataResponse([], Http::STATUS_BAD_REQUEST);
 		}
 
@@ -93,19 +89,11 @@ class PreviewController extends Controller {
 			$mimeType = $this->mimeTypeDetector->detectPath($file);
 			$file = $versionFolder->get($file.'.v'.$version);
 
-			if ($file instanceof Folder) {
-				return new DataResponse([], Http::STATUS_BAD_REQUEST);
-			}
-
 			/** @var File $file */
 			$f = $this->previewManager->getPreview($file, $x, $y, true, IPreview::MODE_FILL, $mimeType);
-
 			return new FileDisplayResponse($f, Http::STATUS_OK, ['Content-Type' => $f->getMimeType()]);
 		} catch (NotFoundException $e) {
 			return new DataResponse([], Http::STATUS_NOT_FOUND);
-		} catch (\Exception $e) {
-			return new DataResponse([], Http::STATUS_INTERNAL_SERVER_ERROR);
 		}
-
 	}
 }
diff --git a/apps/files_versions/tests/Controller/PreviewControllerTest.php b/apps/files_versions/tests/Controller/PreviewControllerTest.php
new file mode 100644
index 0000000000..384f43cf49
--- /dev/null
+++ b/apps/files_versions/tests/Controller/PreviewControllerTest.php
@@ -0,0 +1,167 @@
+<?php
+/**
+ * @copyright Copyright (c) 2016, Roeland Jago Douma <roeland@famdouma.nl>
+ *
+ * @author Roeland Jago Douma <roeland@famdouma.nl>
+ *
+ * @license GNU AGPL version 3 or any later version
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as
+ * published by the Free Software Foundation, either version 3 of the
+ * License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ *
+ */
+namespace OCA\Files_Versions\Tests\Controller;
+
+use OCA\Files_Versions\Controller\PreviewController;
+use OCP\AppFramework\Http;
+use OCP\AppFramework\Http\DataResponse;
+use OCP\AppFramework\Http\FileDisplayResponse;
+use OCP\Files\File;
+use OCP\Files\Folder;
+use OCP\Files\IMimeTypeDetector;
+use OCP\Files\IRootFolder;
+use OCP\Files\NotFoundException;
+use OCP\Files\SimpleFS\ISimpleFile;
+use OCP\IPreview;
+use OCP\IRequest;
+use Test\TestCase;
+
+class PreviewControllerTest extends TestCase {
+
+	/** @var IRootFolder|\PHPUnit_Framework_MockObject_MockObject */
+	private $rootFolder;
+
+	/** @var string */
+	private $userId;
+
+	/** @var IMimeTypeDetector|\PHPUnit_Framework_MockObject_MockObject */
+	private $mimeTypeDetector;
+
+	/** @var IPreview|\PHPUnit_Framework_MockObject_MockObject */
+	private $previewManager;
+
+	/** @var PreviewController */
+	private $controller;
+
+	public function setUp() {
+		parent::setUp();
+
+		$this->rootFolder = $this->createMock(IRootFolder::class);
+		$this->userId = 'user';
+		$this->mimeTypeDetector = $this->createMock(IMimeTypeDetector::class);
+		$this->previewManager = $this->createMock(IPreview::class);
+
+		$this->controller = new PreviewController(
+			'files_versions',
+			$this->createMock(IRequest::class),
+			$this->rootFolder,
+			$this->userId,
+			$this->mimeTypeDetector,
+			$this->previewManager
+		);
+	}
+
+	public function testInvalidFile() {
+		$res = $this->controller->getPreview('');
+		$expected = new DataResponse([], Http::STATUS_BAD_REQUEST);
+
+		$this->assertEquals($expected, $res);
+	}
+
+	public function testInvalidWidth() {
+		$res = $this->controller->getPreview('file', 0);
+		$expected = new DataResponse([], Http::STATUS_BAD_REQUEST);
+
+		$this->assertEquals($expected, $res);
+	}
+
+	public function testInvalidHeight() {
+		$res = $this->controller->getPreview('file', 10, 0);
+		$expected = new DataResponse([], Http::STATUS_BAD_REQUEST);
+
+		$this->assertEquals($expected, $res);
+	}
+
+	public function testInvalidVersion() {
+		$res = $this->controller->getPreview('file', 10, 0);
+		$expected = new DataResponse([], Http::STATUS_BAD_REQUEST);
+
+		$this->assertEquals($expected, $res);
+	}
+
+	public function testValidPreview() {
+		$userFolder = $this->createMock(Folder::class);
+		$userRoot = $this->createMock(Folder::class);
+		$versions = $this->createMock(Folder::class);
+
+		$this->rootFolder->method('getUserFolder')
+			->with($this->userId)
+			->willReturn($userFolder);
+		$userFolder->method('getParent')
+			->willReturn($userRoot);
+		$userRoot->method('get')
+			->with('files_versions')
+			->willReturn($versions);
+
+		$this->mimeTypeDetector->method('detectPath')
+			->with($this->equalTo('file'))
+			->willReturn('myMime');
+
+		$file = $this->createMock(File::class);
+		$versions->method('get')
+			->with($this->equalTo('file.v42'))
+			->willReturn($file);
+
+		$preview = $this->createMock(ISimpleFile::class);
+		$this->previewManager->method('getPreview')
+			->with($this->equalTo($file), 10, 10, true, IPreview::MODE_FILL, 'myMime')
+			->willReturn($preview);
+		$preview->method('getMimeType')
+			->willReturn('previewMime');
+
+		$res = $this->controller->getPreview('file', 10, 10, '42');
+		$expected = new FileDisplayResponse($preview, Http::STATUS_OK, ['Content-Type' => 'previewMime']);
+
+		$this->assertEquals($expected, $res);
+	}
+
+	public function testVersionNotFound() {
+		$userFolder = $this->createMock(Folder::class);
+		$userRoot = $this->createMock(Folder::class);
+		$versions = $this->createMock(Folder::class);
+
+		$this->rootFolder->method('getUserFolder')
+			->with($this->userId)
+			->willReturn($userFolder);
+		$userFolder->method('getParent')
+			->willReturn($userRoot);
+		$userRoot->method('get')
+			->with('files_versions')
+			->willReturn($versions);
+
+		$this->mimeTypeDetector->method('detectPath')
+			->with($this->equalTo('file'))
+			->willReturn('myMime');
+
+		$file = $this->createMock(File::class);
+		$versions->method('get')
+			->with($this->equalTo('file.v42'))
+			->willThrowException(new NotFoundException());
+
+		$res = $this->controller->getPreview('file', 10, 10, '42');
+		$expected = new DataResponse([], Http::STATUS_NOT_FOUND);
+
+		$this->assertEquals($expected, $res);
+	}
+
+}
diff --git a/core/Controller/PreviewController.php b/core/Controller/PreviewController.php
index f54681a856..3a245374e9 100644
--- a/core/Controller/PreviewController.php
+++ b/core/Controller/PreviewController.php
@@ -23,11 +23,11 @@
 
 namespace OC\Core\Controller;
 
-use OC\DatabaseException;
 use OCP\AppFramework\Controller;
 use OCP\Files\File;
 use OCP\AppFramework\Http;
 use OCP\AppFramework\Http\DataResponse;
+use OCP\AppFramework\Http\FileDisplayResponse;
 use OCP\Files\IRootFolder;
 use OCP\Files\NotFoundException;
 use OCP\IPreview;
@@ -86,11 +86,7 @@ class PreviewController extends Controller {
 		$forceIcon = true,
 		$mode = 'fill') {
 
-		if ($file === '') {
-			return new DataResponse([], Http::STATUS_BAD_REQUEST);
-		}
-
-		if ($x === 0 || $y === 0) {
+		if ($file === '' || $x === 0 || $y === 0) {
 			return new DataResponse([], Http::STATUS_BAD_REQUEST);
 		}
 
@@ -109,9 +105,10 @@ class PreviewController extends Controller {
 
 		try {
 			$f = $this->preview->getPreview($file, $x, $y, !$a, $mode);
+			return new FileDisplayResponse($f, Http::STATUS_OK, ['Content-Type' => $f->getMimeType()]);
 		} catch (NotFoundException $e) {
 			return new DataResponse([], Http::STATUS_NOT_FOUND);
 		}
-		return new Http\FileDisplayResponse($f, Http::STATUS_OK, ['Content-Type' => $f->getMimeType()]);
+
 	}
 }
diff --git a/tests/Core/Controller/PreviewControllerTest.php b/tests/Core/Controller/PreviewControllerTest.php
new file mode 100644
index 0000000000..63a2676134
--- /dev/null
+++ b/tests/Core/Controller/PreviewControllerTest.php
@@ -0,0 +1,223 @@
+<?php
+/**
+ * @copyright Copyright (c) 2016, Roeland Jago Douma <roeland@famdouma.nl>
+ *
+ * @author Roeland Jago Douma <roeland@famdouma.nl>
+ *
+ * @license GNU AGPL version 3 or any later version
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as
+ * published by the Free Software Foundation, either version 3 of the
+ * License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ *
+ */
+namespace Tests\Core\Controller;
+
+use OC\Core\Controller\PreviewController;
+use OCP\AppFramework\Http;
+use OCP\AppFramework\Http\DataResponse;
+use OCP\Files\File;
+use OCP\Files\Folder;
+use OCP\Files\IRootFolder;
+use OCP\Files\NotFoundException;
+use OCP\Files\SimpleFS\ISimpleFile;
+use OCP\IPreview;
+use OCP\IRequest;
+
+class PreviewControllerTest extends \Test\TestCase {
+
+	/** @var IRootFolder|\PHPUnit_Framework_MockObject_MockObject */
+	private $rootFolder;
+
+	/** @var string */
+	private $userId;
+
+	/** @var IPreview|\PHPUnit_Framework_MockObject_MockObject */
+	private $previewManager;
+
+	/** @var PreviewController|\PHPUnit_Framework_MockObject_MockObject */
+	private $controller;
+
+	public function setUp() {
+		parent::setUp();
+
+		$this->rootFolder = $this->createMock(IRootFolder::class);
+		$this->userId = 'user';
+		$this->previewManager = $this->createMock(IPreview::class);
+
+		$this->controller = new PreviewController(
+			'core',
+			$this->createMock(IRequest::class),
+			$this->previewManager,
+			$this->rootFolder,
+			$this->userId
+		);
+	}
+
+	public function testInvalidFile() {
+		$res = $this->controller->getPreview('');
+		$expected = new DataResponse([], Http::STATUS_BAD_REQUEST);
+
+		$this->assertEquals($expected, $res);
+	}
+
+	public function testInvalidWidth() {
+		$res = $this->controller->getPreview('file', 0);
+		$expected = new DataResponse([], Http::STATUS_BAD_REQUEST);
+
+		$this->assertEquals($expected, $res);
+	}
+
+	public function testInvalidHeight() {
+		$res = $this->controller->getPreview('file', 10, 0);
+		$expected = new DataResponse([], Http::STATUS_BAD_REQUEST);
+
+		$this->assertEquals($expected, $res);
+	}
+
+	public function testFileNotFound() {
+		$userFolder = $this->createMock(Folder::class);
+		$this->rootFolder->method('getUserFolder')
+			->with($this->equalTo($this->userId))
+			->willReturn($userFolder);
+
+		$userFolder->method('get')
+			->with($this->equalTo('file'))
+			->willThrowException(new NotFoundException());
+
+		$res = $this->controller->getPreview('file');
+		$expected = new DataResponse([], Http::STATUS_NOT_FOUND);
+
+		$this->assertEquals($expected, $res);
+	}
+
+	public function testNotAFile() {
+		$userFolder = $this->createMock(Folder::class);
+		$this->rootFolder->method('getUserFolder')
+			->with($this->equalTo($this->userId))
+			->willReturn($userFolder);
+
+		$folder = $this->createMock(Folder::class);
+		$userFolder->method('get')
+			->with($this->equalTo('file'))
+			->willReturn($folder);
+
+		$res = $this->controller->getPreview('file');
+		$expected = new DataResponse([], Http::STATUS_NOT_FOUND);
+
+		$this->assertEquals($expected, $res);
+	}
+
+	public function testNoPreviewAndNoIcon() {
+		$userFolder = $this->createMock(Folder::class);
+		$this->rootFolder->method('getUserFolder')
+			->with($this->equalTo($this->userId))
+			->willReturn($userFolder);
+
+		$file = $this->createMock(File::class);
+		$userFolder->method('get')
+			->with($this->equalTo('file'))
+			->willReturn($file);
+
+		$this->previewManager->method('isAvailable')
+			->with($this->equalTo($file))
+			->willReturn(false);
+
+		$res = $this->controller->getPreview('file', 10, 10, true, false);
+		$expected = new DataResponse([], Http::STATUS_NOT_FOUND);
+
+		$this->assertEquals($expected, $res);
+	}
+
+	public function testForbiddenFile() {
+		$userFolder = $this->createMock(Folder::class);
+		$this->rootFolder->method('getUserFolder')
+			->with($this->equalTo($this->userId))
+			->willReturn($userFolder);
+
+		$file = $this->createMock(File::class);
+		$userFolder->method('get')
+			->with($this->equalTo('file'))
+			->willReturn($file);
+
+		$this->previewManager->method('isAvailable')
+			->with($this->equalTo($file))
+			->willReturn(true);
+
+		$file->method('isReadable')
+			->willReturn(false);
+
+		$res = $this->controller->getPreview('file', 10, 10, true, true);
+		$expected = new DataResponse([], Http::STATUS_FORBIDDEN);
+
+		$this->assertEquals($expected, $res);
+	}
+
+	public function testNoPreview() {
+		$userFolder = $this->createMock(Folder::class);
+		$this->rootFolder->method('getUserFolder')
+			->with($this->equalTo($this->userId))
+			->willReturn($userFolder);
+
+		$file = $this->createMock(File::class);
+		$userFolder->method('get')
+			->with($this->equalTo('file'))
+			->willReturn($file);
+
+		$this->previewManager->method('isAvailable')
+			->with($this->equalTo($file))
+			->willReturn(true);
+
+		$file->method('isReadable')
+			->willReturn(true);
+
+		$this->previewManager->method('getPreview')
+			->with($this->equalTo($file), 10, 10, false, $this->equalTo('myMode'))
+			->willThrowException(new NotFoundException());
+
+		$res = $this->controller->getPreview('file', 10, 10, true, true, 'myMode');
+		$expected = new DataResponse([], Http::STATUS_NOT_FOUND);
+
+		$this->assertEquals($expected, $res);
+	}
+
+	public function testValidPreview() {
+		$userFolder = $this->createMock(Folder::class);
+		$this->rootFolder->method('getUserFolder')
+			->with($this->equalTo($this->userId))
+			->willReturn($userFolder);
+
+		$file = $this->createMock(File::class);
+		$userFolder->method('get')
+			->with($this->equalTo('file'))
+			->willReturn($file);
+
+		$this->previewManager->method('isAvailable')
+			->with($this->equalTo($file))
+			->willReturn(true);
+
+		$file->method('isReadable')
+			->willReturn(true);
+
+		$preview = $this->createMock(ISimpleFile::class);
+		$this->previewManager->method('getPreview')
+			->with($this->equalTo($file), 10, 10, false, $this->equalTo('myMode'))
+			->willReturn($preview);
+		$preview->method('getMimeType')
+			->willReturn('myMime');
+
+		$res = $this->controller->getPreview('file', 10, 10, true, true, 'myMode');
+		$expected = new Http\FileDisplayResponse($preview, Http::STATUS_OK, ['Content-Type' => 'myMime']);
+
+		$this->assertEquals($expected, $res);
+	}
+}