Services and middleware refactoring

* HTTP responses have been moved back to the controllers
* The environment service has been split in two
* An environment Class has been created to hold the variables the services need to do their job
* The tokencheckmiddleware is now the envcheckmiddleware and makes sure the token is valid before sending it to an environment object
* Some exceptions have been created in order to bubble up problems
* Services have now status codes compatible with HTTP codes
* ThumbnailService is now a child of PrevewService

21 files changed, 1285 insertions, 1103 deletions

diff --git a/appinfo/application.php b/appinfo/application.php
index f1db99bc..00eb7939 100644
--- a/appinfo/application.php
+++ b/appinfo/application.php
@@ -12,7 +12,6 @@
 
 namespace OCA\GalleryPlus\AppInfo;
 
-
 use OCP\IContainer;
 
 use OCP\AppFramework\App;
@@ -21,17 +20,17 @@ use OCP\AppFramework\IAppContainer;
 use OCA\GalleryPlus\Controller\PageController;
 use OCA\GalleryPlus\Controller\ServiceController;
 use OCA\GalleryPlus\Controller\PublicServiceController;
+use OCA\GalleryPlus\Environment\Environment;
 use OCA\GalleryPlus\Preview\Preview;
-use OCA\GalleryPlus\Service\EnvironmentService;
 use OCA\GalleryPlus\Service\InfoService;
 use OCA\GalleryPlus\Service\ThumbnailService;
 use OCA\GalleryPlus\Service\PreviewService;
+use OCA\GalleryPlus\Service\DownloadService;
 use OCA\GalleryPlus\Middleware\SharingCheckMiddleware;
-use OCA\GalleryPlus\Middleware\TokenCheckMiddleware;
+use OCA\GalleryPlus\Middleware\EnvCheckMiddleware;
 use OCA\GalleryPlus\Utility\SmarterLogger;
 use OCA\GalleryPlus\Utility\Normalizer;
 
-
 /**
  * Class Application
  *
@@ -67,10 +66,14 @@ class Application extends App {
 			return new ServiceController(
 				$c->query('AppName'),
 				$c->query('Request'),
+				$c->query('Environment'),
 				$c->query('InfoService'),
 				$c->query('ThumbnailService'),
 				$c->query('PreviewService'),
-				$c->query('URLGenerator')
+				$c->query('DownloadService'),
+				$c->query('URLGenerator'),
+				$c->getServer()
+				  ->createEventSource()
 			);
 		}
 		);
@@ -79,10 +82,14 @@ class Application extends App {
 			return new PublicServiceController(
 				$c->query('AppName'),
 				$c->query('Request'),
+				$c->query('Environment'),
 				$c->query('InfoService'),
 				$c->query('ThumbnailService'),
 				$c->query('PreviewService'),
-				$c->query('URLGenerator')
+				$c->query('DownloadService'),
+				$c->query('URLGenerator'),
+				$c->getServer()
+				  ->createEventSource()
 			);
 		}
 		);
@@ -169,6 +176,7 @@ class Application extends App {
 			'CustomPreviewManager', function (IContainer $c) {
 			return new Preview(
 				$c->query('Config'),
+				$c->query('PreviewManager'),
 				$c->query('SmarterLogger')
 			);
 		}
@@ -191,26 +199,19 @@ class Application extends App {
 					 ->getConfig();
 		}
 		);
-
-		/**
-		 * Services
-		 */
-		// Everything we need to do to set up the environment before processing the request
 		$container->registerService(
-			'Environment', function (IAppContainer $c) {
-			return new EnvironmentService(
+			'Environment', function (IContainer $c) {
+			return new Environment(
 				$c->query('AppName'),
 				$c->query('UserId'),
 				$c->query('UserFolder'),
 				$c->query('UserManager'),
 				$c->getServer(),
-				$c->query('Hasher'),
-				$c->query('Session'),
 				$c->query('SmarterLogger')
 			);
 		}
 		);
-		/*// The same thing as above, but in OC8, hopefully. See https://github.com/owncloud/core/issues/12676
+		/*// The same thing as above, but in OC9, hopefully. See https://github.com/owncloud/core/issues/12676
 		$container->registerService(
 			'Environment', function (IAppContainer $c) {
 			$token = $c->query('Token');
@@ -220,14 +221,17 @@ class Application extends App {
 				->getEnvironment($token);
 		}
 		);*/
+
+		/**
+		 * Services
+		 */
 		$container->registerService(
 			'InfoService', function (IContainer $c) {
 			return new InfoService(
 				$c->query('AppName'),
-				$c->query('UserFolder'),
-				$c->query('Environment'),
-				$c->query('SmarterLogger'),
-				$c->query('PreviewManager')
+				$c->query('PreviewService'),
+				$c->query('SmarterLogger')
+
 			);
 		}
 		);
@@ -235,10 +239,10 @@ class Application extends App {
 			'ThumbnailService', function (IAppContainer $c) {
 			return new ThumbnailService(
 				$c->query('AppName'),
-				$c->query('SmarterLogger'),
-				$c->getServer()
-				  ->createEventSource(),
-				$c->query('PreviewService')
+				$c->query('Environment'),
+				$c->query('CustomPreviewManager'),
+				$c->query('SmarterLogger')
+
 			);
 		}
 		);
@@ -247,8 +251,18 @@ class Application extends App {
 			return new PreviewService(
 				$c->query('AppName'),
 				$c->query('Environment'),
-				$c->query('SmarterLogger'),
-				$c->query('CustomPreviewManager')
+				$c->query('CustomPreviewManager'),
+				$c->query('SmarterLogger')
+
+			);
+		}
+		);
+		$container->registerService(
+			'DownloadService', function (IContainer $c) {
+			return new DownloadService(
+				$c->query('AppName'),
+				$c->query('Environment'),
+				$c->query('SmarterLogger')
 			);
 		}
 		);
@@ -270,11 +284,13 @@ class Application extends App {
 			}
 		);
 		$container->registerService(
-			'TokenCheckMiddleware',
+			'EnvCheckMiddleware',
 			function (IContainer $c) {
-				return new TokenCheckMiddleware(
+				return new EnvCheckMiddleware(
 					$c->query('AppName'),
 					$c->query('Request'),
+					$c->query('Hasher'),
+					$c->query('Session'),
 					$c->query('Environment'),
 					$c->query('ControllerMethodReflector'),
 					$c->query('URLGenerator'),
@@ -285,7 +301,8 @@ class Application extends App {
 
 		// executed in the order that it is registered
 		$container->registerMiddleware('SharingCheckMiddleware');
-		$container->registerMiddleware('TokenCheckMiddleware');
+		$container->registerMiddleware('EnvCheckMiddleware');
+
 	}
 
 }
\ No newline at end of file
diff --git a/controller/jsonhttperror.php b/controller/jsonhttperror.php
index 23a88938..6f7fe2b9 100644
--- a/controller/jsonhttperror.php
+++ b/controller/jsonhttperror.php
@@ -14,8 +14,14 @@
 
 namespace OCA\GalleryPlus\Controller;
 
+use Exception;
+
+use OCP\AppFramework\Http;
 use OCP\AppFramework\Http\JSONResponse;
 
+use OCA\GalleryPlus\Environment\NotFoundEnvException;
+use OCA\GalleryPlus\Service\NotFoundServiceException;
+
 /**
  * Our classes extend both Controller and ApiController, so we need to use
  * traits to add some common methods
@@ -27,14 +33,14 @@ trait JsonHttpError {
 	/**
 	 * @param \Exception $exception the message that is returned taken from the exception
 	 *
-	 * @param int $code the http error code
-	 *
 	 * @return JSONResponse
 	 */
-	public function error(\Exception $exception, $code = 0) {
+	public function error(Exception $exception) {
 		$message = $exception->getMessage();
-		if ($code === 0) {
-			$code = $exception->getCode();
+		$code = Http::STATUS_INTERNAL_SERVER_ERROR;
+
+		if ($exception instanceof NotFoundServiceException || $exception instanceof NotFoundEnvException) {
+			$code = Http::STATUS_NOT_FOUND;
 		}
 
 		return new JSONResponse(
diff --git a/controller/pagecontroller.php b/controller/pagecontroller.php
index 6de271c8..e0d04445 100644
--- a/controller/pagecontroller.php
+++ b/controller/pagecontroller.php
@@ -20,7 +20,7 @@ use OCP\IRequest;
 use OCP\AppFramework\Controller;
 use OCP\AppFramework\Http\TemplateResponse;
 
-use OCA\GalleryPlus\Service\EnvironmentService;
+use OCA\GalleryPlus\Environment\Environment;
 
 /**
  * Generates templates for the landing page from within ownCloud, the public
@@ -31,9 +31,9 @@ use OCA\GalleryPlus\Service\EnvironmentService;
 class PageController extends Controller {
 
 	/**
-	 * @type EnvironmentService
+	 * @type Environment
 	 */
-	private $environmentService;
+	private $environment;
 	/**
 	 * @type IURLGenerator
 	 */
@@ -44,18 +44,18 @@ class PageController extends Controller {
 	 *
 	 * @param string $appName
 	 * @param IRequest $request
-	 * @param EnvironmentService $environmentService
+	 * @param Environment $environment
 	 * @param IURLGenerator $urlGenerator
 	 */
 	public function __construct(
 		$appName,
 		IRequest $request,
-		EnvironmentService $environmentService,
+		Environment $environment,
 		IURLGenerator $urlGenerator
 	) {
 		parent::__construct($appName, $request);
 
-		$this->environmentService = $environmentService;
+		$this->environment = $environment;
 		$this->urlGenerator = $urlGenerator;
 	}
 
@@ -94,10 +94,8 @@ class PageController extends Controller {
 	public function publicIndex() {
 		$appName = $this->appName;
 		$token = $this->request->getParam('token');
-
-		$env = $this->environmentService->getEnv();
-		$displayName = $env['originalOwnerDisplayName'];
-		$albumName = $env['albumName'];
+		$displayName = $this->environment->getDisplayName();
+		$albumName = $this->environment->getSharedFolderName();
 
 		// Parameters sent to the template
 		$params = [
diff --git a/controller/servicecontroller.php b/controller/servicecontroller.php
index e0b00be2..24959c58 100644
--- a/controller/servicecontroller.php
+++ b/controller/servicecontroller.php
@@ -14,16 +14,21 @@
 
 namespace OCA\GalleryPlus\Controller;
 
+use OCP\IEventSource;
 use OCP\IURLGenerator;
 use OCP\IRequest;
 
 use OCP\AppFramework\Controller;
 use OCP\AppFramework\Http;
 
+use OCA\GalleryPlus\Environment\Environment;
+use OCA\GalleryPlus\Environment\EnvironmentException;
+use OCA\GalleryPlus\Http\ImageResponse;
+use OCA\GalleryPlus\Service\ServiceException;
 use OCA\GalleryPlus\Service\InfoService;
 use OCA\GalleryPlus\Service\ThumbnailService;
 use OCA\GalleryPlus\Service\PreviewService;
-use OCA\GalleryPlus\Service\ServiceException;
+use OCA\GalleryPlus\Service\DownloadService;
 
 /**
  * Class ServiceController
@@ -35,6 +40,10 @@ class ServiceController extends Controller {
 	use JsonHttpError;
 
 	/**
+	 * @type Environment
+	 */
+	private $environment;
+	/**
 	 * @type InfoService
 	 */
 	private $infoService;
@@ -47,34 +56,51 @@ class ServiceController extends Controller {
 	 */
 	private $previewService;
 	/**
+	 * @type DownloadService
+	 */
+	private $downloadService;
+	/**
 	 * @type IURLGenerator
 	 */
 	private $urlGenerator;
+	/**
+	 * @type IEventSource
+	 */
+	private $eventSource;
 
 	/**
 	 * Constructor
 	 *
 	 * @param string $appName
 	 * @param IRequest $request
+	 * @param Environment $environment
 	 * @param InfoService $infoService
 	 * @param ThumbnailService $thumbnailService
 	 * @param PreviewService $previewService
+	 * @param DownloadService $downloadService
 	 * @param IURLGenerator $urlGenerator
+	 * @param IEventSource $eventSource
 	 */
 	public function __construct(
 		$appName,
 		IRequest $request,
+		Environment $environment,
 		InfoService $infoService,
 		ThumbnailService $thumbnailService,
 		PreviewService $previewService,
-		IURLGenerator $urlGenerator
+		DownloadService $downloadService,
+		IURLGenerator $urlGenerator,
+		IEventSource $eventSource
 	) {
 		parent::__construct($appName, $request);
 
+		$this->environment = $environment;
 		$this->infoService = $infoService;
 		$this->thumbnailService = $thumbnailService;
 		$this->previewService = $previewService;
+		$this->downloadService = $downloadService;
 		$this->urlGenerator = $urlGenerator;
+		$this->eventSource = $eventSource;
 	}
 
 	/**
@@ -86,13 +112,15 @@ class ServiceController extends Controller {
 	 *
 	 * @param string $albumpath
 	 *
-	 * @return array|Http\JSONResponse
+	 * @return array<string,int>|Http\JSONResponse
 	 */
 	public function getAlbumInfo($albumpath) {
 		try {
+			$nodeInfo = $this->environment->getNodeInfo($albumpath);
+
 			// Thanks to the AppFramework, Arrays are automatically JSON encoded
-			return $this->infoService->getAlbumInfo($albumpath);
-		} catch (ServiceException $exception) {
+			return $nodeInfo;
+		} catch (EnvironmentException $exception) {
 			return $this->error($exception);
 		}
 	}
@@ -111,14 +139,27 @@ class ServiceController extends Controller {
 	/**
 	 * @NoAdminRequired
 	 *
-	 * Returns a list of all images available to the logged-in user
+	 * Returns a list of all images available to the authenticated user
+	 *
+	 * Authentication can be via a login/password or a token/(password)
+	 *
+	 * For private galleries, it returns all images, with the full path from the root folder
+	 * For public galleries, the path starts from the folder the link gives access to
 	 *
 	 * @return array|Http\JSONResponse
 	 */
 	public function getImages() {
 		try {
-			return $this->infoService->getImages();
-		} catch (ServiceException $exception) {
+			$imagesFolder = $this->environment->getResourceFromPath('');
+			$fromRootToFolder = $this->environment->getFromRootToFolder();
+
+			$folderData = [
+				'imagesFolder'     => $imagesFolder,
+				'fromRootToFolder' => $fromRootToFolder,
+			];
+
+			return $this->infoService->getImages($folderData);
+		} catch (EnvironmentException $exception) {
 			return $this->error($exception);
 		}
 	}
@@ -130,34 +171,56 @@ class ServiceController extends Controller {
 	 *
 	 * Uses EventSource to send thumbnails back as soon as they're created
 	 *
+	 * FIXME: @LukasReschke says: The exit is required here because
+	 * otherwise the AppFramework is trying to add headers as well after
+	 * dispatching the request which results in a "Cannot modify header
+	 * information" notice.
+	 *
+	 * WARNING: Returning a JSON response does not work.
+	 *
 	 * @param string $images
 	 * @param bool $square
 	 * @param bool $scale
 	 *
-	 * @return Http\JSONResponse|null
+	 * @return null|Http\JSONResponse
 	 */
 	public function getThumbnails($images, $square, $scale) {
-		try {
-			$this->thumbnailService->getAlbumThumbnails($images, $square, $scale);
-		} catch (ServiceException $exception) {
-			return $this->error($exception);
+		$imagesArray = explode(';', $images);
+
+		foreach ($imagesArray as $image) {
+			$thumbnail = $this->getThumbnail($image, $square, $scale);
+			$this->eventSource->send('preview', $thumbnail);
 		}
+		$this->eventSource->close();
+		exit();
 	}
 
 	/**
 	 * @NoAdminRequired
 	 *
-	 * Shows a large preview of a file
+	 * Sends either a large preview of the requested file or the
+	 * original file itself
+	 *
+	 * If the browser can use the file as-is then we simply let
+	 * the browser download the file, straight from the filesystem
 	 *
 	 * @param string $file
 	 * @param int $x
 	 * @param int $y
 	 *
-	 * @return \OCA\GalleryPlus\Http\ImageResponse|Http\JSONResponse
+	 * @return ImageResponse|Http\JSONResponse
 	 */
 	public function showPreview($file, $x, $y) {
 		try {
-			return $this->previewService->showPreview($file, $x, $y);
+			$animatedPreview = true;
+			$previewRequired = $this->previewService->isPreviewRequired($file, $animatedPreview);
+			if ($previewRequired) {
+				$preview = $this->previewService->createPreview($file, $x, $y);
+			} else {
+				$preview = $this->downloadService->downloadFile($file);
+			}
+
+			return new ImageResponse($preview, $preview['status']);
 		} catch (ServiceException $exception) {
 			return $this->error($exception);
 		}
@@ -174,7 +237,36 @@ class ServiceController extends Controller {
 	 */
 	public function downloadPreview($file) {
 		try {
-			return $this->previewService->downloadPreview($file);
+			$download = $this->downloadService->downloadFile($file);
+
+			return new ImageResponse($download, $download['status']);
+		} catch (EnvironmentException $exception) {
+			return $this->error($exception);
+		}
+	}
+
+	/**
+	 * Retrieves the thumbnail to send back to the browser
+	 *
+	 * The thumbnail is either a resized preview of the file or the original file
+	 *
+	 * @param string $image
+	 * @param bool $square
+	 * @param bool $scale
+	 *
+	 * @return array
+	 */
+	private function getThumbnail($image, $square, $scale) {
+		try {
+			$previewRequired =
+				$this->previewService->isPreviewRequired($image, $animatedPreview = false);
+			if ($previewRequired) {
+				$thumbnail = $this->thumbnailService->createThumbnail($image, $square, $scale);
+			} else {
+				$thumbnail = $this->downloadService->downloadFile($image, $base64Encode = true);
+			}
+
+			return $thumbnail;
 		} catch (ServiceException $exception) {
 			return $this->error($exception);
 		}
diff --git a/environment/environment.php b/environment/environment.php
new file mode 100644
index 00000000..480b9076
--- /dev/null
+++ b/environment/environment.php
@@ -0,0 +1,334 @@
+<?php
+/**
+ * ownCloud - galleryplus
+ *
+ * This file is licensed under the Affero General Public License version 3 or
+ * later. See the COPYING file.
+ *
+ * @author Olivier Paroz <owncloud@interfasys.ch>
+ * @author Authors of \OCA\Files_Sharing\Helper
+ *
+ * @copyright Olivier Paroz 2015
+ * @copyright Authors of \OCA\Files_Sharing\Helper 2014-2015
+ */
+
+namespace OCA\GalleryPlus\Environment;
+
+use OCP\IServerContainer;
+use OCP\IUserManager;
+use OCP\Share;
+use OCP\Files\Folder;
+use OCP\Files\Node;
+use OCP\Files\NotFoundException;
+
+use OCA\GalleryPlus\Utility\SmarterLogger;
+
+/**
+ * Builds the environment so that the services have access to the files and folders' owner
+ *
+ * @todo remove the serverContainer once OCP\IUserManager has a getUserFolder() method
+ *
+ * @package OCA\GalleryPlus\Environment
+ */
+class Environment {
+
+	/**
+	 * @type string
+	 */
+	private $appName;
+	/**
+	 * The userId of the logged-in user or the person sharing a folder publicly
+	 *
+	 * @type string
+	 */
+	private $userId;
+	/**
+	 * The userFolder of the logged-in user or the ORIGINAL owner of the files which are shared
+	 * publicly
+	 *
+	 * A share needs to be tracked back to its original owner in order to be able to access the
+	 * resource
+	 *
+	 * @type Folder|null
+	 */
+	private $userFolder;
+	/**
+	 * @type IUserManager
+	 */
+	private $userManager;
+	/**
+	 * @type IServerContainer
+	 */
+	private $serverContainer;
+	/**
+	 * @type SmarterLogger
+	 */
+	private $logger;
+	/**
+	 * The path to the userFolder for users with accounts: /userId/files
+	 *
+	 * For public folders, it's the path from the shared folder to the root folder in the original
+	 * owner's filesystem: /userId/files/parent_folder/shared_folder
+	 *
+	 * @type string
+	 */
+	private $fromRootToFolder;
+	/**
+	 * The name of the shared folder
+	 *
+	 * @type string
+	 */
+	private $folderName;
+
+	/***
+	 * Constructor
+	 *
+	 * @param string $appName
+	 * @param string|null $userId
+	 * @param Folder|null $userFolder
+	 * @param IUserManager $userManager
+	 * @param IServerContainer $serverContainer
+	 * @param SmarterLogger $logger
+	 */
+	public function __construct(
+		$appName,
+		$userId,
+		$userFolder,
+		IUserManager $userManager,
+		IServerContainer $serverContainer,
+		SmarterLogger $logger
+	) {
+		$this->appName = $appName;
+		$this->userId = $userId;
+		$this->userFolder = $userFolder;
+		$this->userManager = $userManager;
+		$this->serverContainer = $serverContainer;
+		$this->logger = $logger;
+	}
+
+	/**
+	 * Creates the environment based on the linkItem the token links to
+	 *
+	 * @param array $linkItem
+	 */
+	public function setTokenBasedEnv($linkItem) {
+		// Resolves reshares down to the last real share
+		$rootLinkItem = Share::resolveReShare($linkItem);
+		$origShareOwner = $rootLinkItem['uid_owner'];
+		$this->userFolder = $this->setupFilesystem($origShareOwner);
+
+		$fileSource = $linkItem['file_source'];
+		$this->fromRootToFolder = $this->buildFromRootToFolder($fileSource);
+
+		$this->folderName = $linkItem['file_target'];
+		$this->userId = $linkItem['uid_owner'];
+	}
+
+	/**
+	 * Creates the environment for a logged-in user
+	 *
+	 * userId and userFolder are already known, we define fromRootToFolder
+	 * so that the services can use one method to have access resources
+	 * without having to know whether they're private or public
+	 */
+	public function setStandardEnv() {
+		$this->fromRootToFolder = $this->userFolder->getPath() . '/';
+	}
+
+	/**
+	 * Returns the resource located at the given path
+	 *
+	 * The path starts from the user's files folder
+	 * The resource is either a File or a Folder
+	 *
+	 * @param string $subPath
+	 *
+	 * @return Node
+	 */
+	public function getResourceFromPath($subPath) {
+		$path = $this->getImagePathFromFolder($subPath);
+		$nodeInfo = $this->getNodeInfo($path);
+
+		return $this->getResourceFromId($nodeInfo['fileid']);
+	}
+
+	/**
+	 * Returns the Node based on the current user's files folder and a given
+	 * path
+	 *
+	 * @param string $path
+	 *
+	 * @return array<string,int>|false
+	 *
+	 * @throws EnvironmentException
+	 */
+	public function getNodeInfo($path) {
+		$nodeInfo = false;
+		$folder = $this->userFolder;
+		if ($folder === null) {
+			$this->logAndThrowNotFound("Could not access the user's folder");
+		} else {
+			try {
+				$node = $folder->get($path);
+				$nodeInfo = [
+					'fileid'      => $node->getId(),
+					'permissions' => $node->getPermissions()
+				];
+			} catch (NotFoundException $exception) {
+				$message = 'Could not find anything at: ' . $exception->getMessage();
+				$this->logAndThrowNotFound($message);
+			}
+		}
+
+		return $nodeInfo;
+	}
+
+
+	/**
+	 * Returns the userId of the currently logged-in user or the sharer
+	 *
+	 * @return string
+	 */
+	public function getUserID() {
+		return $this->userId;
+	}
+
+	/**
+	 * Returns the name of the user sharing files publicly
+	 *
+	 * @return string
+	 */
+	public function getDisplayName() {
+		$user = null;
+		$userId = $this->userId;
+
+		if (isset($userId)) {
+			$user = $this->userManager->get($userId);
+		}
+		if ($user === null) {
+			$this->logAndThrowNotFound('Could not find user');
+		}
+
+		return $user->getDisplayName();
+	}
+
+	/**
+	 * Returns the name of shared folder
+	 *
+	 * @return string
+	 */
+	public function getSharedFolderName() {
+		return trim($this->folderName, '//');
+	}
+
+	/**
+	 * Returns /parent_folder/current_folder/_my_file
+	 *
+	 * getPath() on the file produces a path like:
+	 * '/userId/files/my_folder/my_sub_folder'
+	 *
+	 * So we substract the path to the folder, giving us a relative path
+	 * '/my_folder/my_sub_folder'
+	 *
+	 * @param string $image
+	 *
+	 * @return string
+	 */
+	public function getImagePathFromFolder($image) {
+		$origSharePath = $this->fromRootToFolder;
+		$folderPath = $this->userFolder->getPath();
+		$origShareRelPath = str_replace($folderPath, '', $origSharePath);
+		$relativePath = $origShareRelPath;
+
+		/*$this->logger->debug(
+			'Full Path {origSharePath}, folder path {folderPath}, relative path {relativePath}',
+			[
+				'origSharePath' => $origSharePath,
+				'folderPath'    => $folderPath,
+				'relativePath'  => $relativePath
+			]
+		);*/
+
+		return $relativePath . '/' . $image;
+	}
+
+	/**
+	 * Returns fromRootToFolder
+	 *
+	 * @see buildFromRootToFolder
+	 *
+	 * @return string
+	 */
+	public function getFromRootToFolder() {
+		return $this->fromRootToFolder;
+	}
+
+	/**
+	 * Sets up the filesystem for the original share owner so that we can
+	 * retrieve the files and returns the userFolder for that user
+	 *
+	 * We can't use 'UserFolder' from Application as the user is not known
+	 * at instantiation time
+	 *
+	 * @param $origShareOwner
+	 *
+	 * @return Folder
+	 */
+	private function setupFilesystem($origShareOwner) {
+		\OC_Util::tearDownFS(); // FIXME: Private API
+		\OC_Util::setupFS($origShareOwner); // FIXME: Private API
+
+		$folder = $this->serverContainer->getUserFolder($origShareOwner);
+		/*// Alternative which does not exist yet
+		$user = $this->userManager->get($origShareOwner);
+		$folder = $user->getUserFolder();*/
+
+		return $folder;
+	}
+
+	/**
+	 * Returns the path from the shared folder to the root folder in the original
+	 * owner's filesystem: /userId/files/parent_folder/shared_folder
+	 *
+	 * @param string $fileSource
+	 *
+	 * @return string
+	 */
+	private function buildFromRootToFolder($fileSource) {
+		$resource = $this->getResourceFromId($fileSource);
+		$fromRootToFolder = $resource->getPath() . '/';
+
+		return $fromRootToFolder;
+	}
+
+	/**
+	 * Returns the resource identified by the given ID
+	 *
+	 * @param int $resourceId
+	 *
+	 * @return Node
+	 *
+	 * @throws EnvironmentException
+	 */
+	private function getResourceFromId($resourceId) {
+		$resourcesArray = $this->userFolder->getById($resourceId);
+		if ($resourcesArray[0] === null) {
+			$this->logAndThrowNotFound('Could not resolve linkItem');
+		}
+
+		return $resourcesArray[0];
+	}
+
+	/**
+	 * Logs the error and raises an exception
+	 *
+	 * @param string $message
+	 *
+	 * @throws NotFoundEnvException
+	 */
+	private function logAndThrowNotFound($message) {
+		$this->logger->error($message . ' (404)');
+		throw new NotFoundEnvException($message);
+	}
+
+}
\ No newline at end of file
diff --git a/environment/environmentexception.php b/environment/environmentexception.php
new file mode 100644
index 00000000..9481797f
--- /dev/null
+++ b/environment/environmentexception.php
@@ -0,0 +1,28 @@
+<?php
+/**
+ * ownCloud - galleryplus
+ *
+ * This file is licensed under the Affero General Public License version 3 or
+ * later. See the COPYING file.
+ *
+ * @author Olivier Paroz <owncloud@interfasys.ch>
+ *
+ * @copyright Olivier Paroz 2015
+ */
+
+namespace OCA\GalleryPlus\Environment;
+
+use Exception;
+
+/**
+ * Thrown when the service cannot reply to a request
+ */
+class EnvironmentException extends Exception {
+
+	/**
+	 * Constructor
+	 *
+	 * @param string $msg the message contained in the exception
+	 */
+	public function __construct($msg) {}
+}
\ No newline at end of file
diff --git a/environment/notfoundenvexception.php b/environment/notfoundenvexception.php
new file mode 100644
index 00000000..9589fa9a
--- /dev/null
+++ b/environment/notfoundenvexception.php
@@ -0,0 +1,26 @@
+<?php
+/**
+ * ownCloud - galleryplus
+ *
+ * This file is licensed under the Affero General Public License version 3 or
+ * later. See the COPYING file.
+ *
+ * @author Olivier Paroz <owncloud@interfasys.ch>
+ *
+ * @copyright Olivier Paroz 2015
+ */
+
+namespace OCA\GalleryPlus\Environment;
+
+/**
+ * Thrown when the service cannot reply to a request
+ */
+class NotFoundEnvException extends EnvironmentException {
+
+	/**
+	 * Constructor
+	 *
+	 * @param string $msg the message contained in the exception
+	 */
+	public function __construct($msg) {}
+}
\ No newline at end of file
diff --git a/middleware/checkmiddleware.php b/middleware/checkmiddleware.php
index 81e2a30c..e13b14e6 100644
--- a/middleware/checkmiddleware.php
+++ b/middleware/checkmiddleware.php
@@ -90,6 +90,19 @@ abstract class CheckMiddleware extends Middleware {
 	}
 
 	/**
+	 * Logs the error and raises an exception
+	 *
+	 * @param string $message
+	 * @param int $code
+	 *
+	 * @throws CheckException
+	 */
+	protected function logAndThrow($message, $code) {
+		$this->logger->error($message . ' (' . $code . ')');
+		throw new CheckException($message, $code);
+	}
+
+	/**
 	 * Decides which type of response to send
 	 *
 	 * @param string $message
diff --git a/middleware/envcheckmiddleware.php b/middleware/envcheckmiddleware.php
new file mode 100644
index 00000000..1e4de129
--- /dev/null
+++ b/middleware/envcheckmiddleware.php
@@ -0,0 +1,316 @@
+<?php
+/**
+ * ownCloud - galleryplus
+ *
+ * This file is licensed under the Affero General Public License version 3 or
+ * later. See the COPYING file.
+ *
+ * @author Olivier Paroz <owncloud@interfasys.ch>
+ * @author Bernhard Posselt <dev@bernhard-posselt.com>
+ * @author Authors of \OCA\Files_Sharing\Helper
+ *
+ * @copyright Olivier Paroz 2014-2015
+ * @copyright Bernhard Posselt 2012-2015
+ * @copyright Authors of \OCA\Files_Sharing\Helper 2014-2015
+ */
+
+namespace OCA\GalleryPlus\Middleware;
+
+use OCP\IRequest;
+use OCP\IURLGenerator;
+use OCP\ISession;
+use OCP\Share;
+use OCP\Security\IHasher;
+
+use OCP\AppFramework\Http;
+use OCP\AppFramework\Utility\IControllerMethodReflector;
+
+use OCA\GalleryPlus\Environment\Environment;
+use OCA\GalleryPlus\Service\ServiceException;
+use OCA\GalleryPlus\Utility\SmarterLogger;
+
+/**
+ * Checks that we have a valid token linked to a valid resource and that the
+ * user is authorised to access it
+ *
+ * Once all checks have been passed, the environment is ready to use
+ *
+ * @package OCA\GalleryPlus\Middleware
+ */
+class EnvCheckMiddleware extends CheckMiddleware {
+
+	/**
+	 * @type IHasher
+	 * */
+	private $hasher;
+	/**
+	 * @type ISession
+	 * */
+	private $session;
+	/**
+	 * @type Environment
+	 */
+	private $environment;
+	/**
+	 * @type IControllerMethodReflector
+	 */
+	protected $reflector;
+
+	/***
+	 * Constructor
+	 *
+	 * @param string $appName
+	 * @param IHasher $hasher
+	 * @param ISession $session
+	 * @param IRequest $request
+	 * @param IControllerMethodReflector $reflector
+	 * @param IURLGenerator $urlGenerator
+	 * @param SmarterLogger $logger
+	 * @param Environment $environment
+	 * @param SmarterLogger $logger
+	 */
+	public function __construct(
+		$appName,
+		IRequest $request,
+		IHasher $hasher,
+		ISession $session,
+		Environment $environment,
+		IControllerMethodReflector $reflector,
+		IURLGenerator $urlGenerator,
+		SmarterLogger $logger
+	) {
+		parent::__construct(
+			$appName,
+			$request,
+			$urlGenerator,
+			$logger
+		);
+
+		$this->hasher = $hasher;
+		$this->session = $session;
+		$this->environment = $environment;
+		$this->reflector = $reflector;
+	}
+
+	/**
+	 * Checks that we have a valid token linked to a valid resource and that the
+	 * user is authorised to access it
+	 *
+	 * Inspects the controller method annotations and if PublicPage is found
+	 * it checks that we have a token and an optional password giving access to a valid resource.
+	 * Once that's done, the environment is setup so that our services can find the resources they
+	 * need.
+	 *
+	 * The checks are not performed on "guest" pages and the environment is not setup. Typical
+	 * guest pages are anonymous error ages
+	 *
+	 * @inheritDoc
+	 */
+	public function beforeController($controller, $methodName) {
+		if ($this->reflector->hasAnnotation('Guest')) {
+			return;
+		}
+		$isPublicPage = $this->reflector->hasAnnotation('PublicPage');
+		if ($isPublicPage) {
+			$this->validateAndSetTokenBasedEnv();
+		} else {
+			$this->environment->setStandardEnv();
+		}
+	}
+
+	/**
+	 * Checks that we have a token and an optional password giving access to a
+	 * valid resource. Sets the token based environment after that
+	 */
+	private function validateAndSetTokenBasedEnv() {
+		$token = $this->request->getParam('token');
+		if (!$token) {
+			$this->noTokenFound();
+		} else { // We have a token
+			// Let's see if it's linked to a valid resource
+			$linkItem = $this->getLinkItem($token);
+			$password = $this->request->getParam('password');
+			// Let's see if the user needs to provide a password
+			$this->checkAuthorisation($linkItem, $password);
+
+			$this->environment->setTokenBasedEnv($linkItem);
+		}
+	}
+
+	/**
+	 * Throws an exception because no token was provided
+	 *
+	 * @throws CheckException
+	 */
+	private function noTokenFound() {
+		$this->logAndThrow(
+			"Can't access a public resource without a token", Http::STATUS_NOT_FOUND
+		);
+	}
+
+	/**
+	 * Validates a token to make sure its linked to a valid resource
+	 *
+	 * Logic mostly duplicated from @see \OCA\Files_Sharing\Helper
+	 *
+	 * @fixme setIncognitoMode in 8.1 https://github.com/owncloud/core/pull/12912
+	 *
+	 * @param string $token
+	 *
+	 * @return array|bool
+	 *
+	 * @throws CheckException
+	 */
+	private function getLinkItem($token) {
+		// Allows a logged in user to access public links
+		\OC_User::setIncognitoMode(true);
+
+		$linkItem = Share::getShareByToken($token, false);
+
+		$this->checkLinkItemExists($linkItem);
+		$this->checkLinkItemIsValid($linkItem, $token);
+		$this->checkItemType($linkItem);
+
+		// Checks passed, let's store the linkItem
+		return $linkItem;
+	}
+
+	/**
+	 * Makes sure that the token exists
+	 *
+	 * @param array|bool $linkItem
+	 */
+	private function checkLinkItemExists($linkItem) {
+		if ($linkItem === false
+			|| ($linkItem['item_type'] !== 'file'
+				&& $linkItem['item_type'] !== 'folder')
+		) {
+			$message = 'Passed token parameter is not valid';
+			$this->logAndThrow($message, Http::STATUS_BAD_REQUEST);
+		}
+	}
+
+	/**
+	 * Makes sure that the token contains all the information that we need
+	 *
+	 * @param array|bool $linkItem
+	 * @param string $token
+	 */
+	private function checkLinkItemIsValid($linkItem, $token) {
+		if (!isset($linkItem['uid_owner'])
+			|| !isset($linkItem['file_source'])
+		) {
+			$message =
+				'Passed token seems to be valid, but it does not contain all necessary information . ("'
+				. $token . '")';
+			$this->logAndThrow($message, Http::STATUS_NOT_FOUND);
+		}
+	}
+
+	/**
+	 * Makes sure an item type was set for that token
+	 *
+	 * @param array|bool $linkItem
+	 */
+	private function checkItemType($linkItem) {
+		if (!isset($linkItem['item_type'])) {
+			$message = 'No item type set for share id: ' . $linkItem['id'];
+			$this->logAndThrow($message, Http::STATUS_NOT_FOUND);
+		}
+	}
+
+	/**
+	 * Checks if a password is required or if the one supplied is working
+	 *
+	 * @param array|bool $linkItem
+	 * @param string|null $password optional password
+	 *
+	 * @throws CheckException
+	 */
+	private function checkAuthorisation($linkItem, $password) {
+		$passwordRequired = isset($linkItem['share_with']);
+
+		if ($passwordRequired) {
+			if ($password !== null) {
+				$this->authenticate($linkItem, $password);
+			} else {
+				$this->checkSession($linkItem);
+			}
+		}
+	}
+
+	/**
+	 * Authenticate link item with the given password
+	 * or with the session if no password was given.
+	 *
+	 * @fixme @LukasReschke says: Migrate old hashes to new hash format
+	 * Due to the fact that there is no reasonable functionality to update the password
+	 * of an existing share no migration is yet performed there.
+	 * The only possibility is to update the existing share which will result in a new
+	 * share ID and is a major hack.
+	 *
+	 * In the future the migration should be performed once there is a proper method
+	 * to update the share's password. (for example `$share->updatePassword($password)`
+	 *
+	 * @link https://github.com/owncloud/core/issues/10671
+	 *
+	 * @param array|bool $linkItem
+	 * @param string $password
+	 *
+	 * @return bool true if authorized, an exception is raised otherwise
+	 *
+	 * @throws ServiceException
+	 */
+	private function authenticate($linkItem, $password) {
+		if ($linkItem['share_type'] == Share::SHARE_TYPE_LINK) {
+			$this->checkPassword($linkItem, $password);
+		} else {
+			$this->logAndThrow(
+				'Unknown share type ' . $linkItem['share_type'] . ' for share id '
+				. $linkItem['id'], Http::STATUS_NOT_FOUND
+			);
+		}
+
+		return true;
+	}
+
+	/**
+	 * Validates the given password
+	 *
+	 * @param array|bool $linkItem
+	 * @param string $password
+	 *
+	 * @throws ServiceException
+	 */
+	private function checkPassword($linkItem, $password) {
+		$newHash = '';
+		if ($this->hasher->verify($password, $linkItem['share_with'], $newHash)) {
+
+			// Save item id in session for future requests
+			$this->session->set('public_link_authenticated', $linkItem['id']);
+			if (!empty($newHash)) {
+				// For future use
+			}
+		} else {
+			$this->logAndThrow("Wrong password", Http::STATUS_UNAUTHORIZED);
+		}
+	}
+
+	/**
+	 * Makes sure the user is already properly authenticated when a password is required and none
+	 * was provided
+	 *
+	 * @param array|bool $linkItem
+	 *
+	 * @throws ServiceException
+	 */
+	private function checkSession($linkItem) {
+		// Not authenticated ?
+		if (!$this->session->exists('public_link_authenticated')
+			|| $this->session->get('public_link_authenticated') !== $linkItem['id']
+		) {
+			$this->logAndThrow("Missing password", Http::STATUS_UNAUTHORIZED);
+		}
+	}
+
+}
\ No newline at end of file
diff --git a/middleware/sharingcheckmiddleware.php b/middleware/sharingcheckmiddleware.php
index d147d427..b623c479 100644
--- a/middleware/sharingcheckmiddleware.php
+++ b/middleware/sharingcheckmiddleware.php
@@ -82,17 +82,11 @@ class SharingCheckMiddleware extends CheckMiddleware {
 	public function beforeController($controller, $methodName) {
 		$sharingEnabled = $this->isSharingEnabled();
 
-		// This needs to be done here as the Dispatcher does not call our reflector
-		//$this->reflector->reflect($controller, $methodName);
-
 		$isPublicPage = $this->reflector->hasAnnotation('PublicPage');
 		$isGuest = $this->reflector->hasAnnotation('Guest');
 
 		if ($isPublicPage && !$isGuest && !$sharingEnabled) {
-			throw new CheckException(
-				'Sharing is disabled',
-				Http::STATUS_SERVICE_UNAVAILABLE
-			);
+			$this->logAndThrow("'Sharing is disabled'", Http::STATUS_SERVICE_UNAVAILABLE);
 		}
 	}
 
diff --git a/middleware/tokencheckmiddleware.php b/middleware/tokencheckmiddleware.php
deleted file mode 100644
index 5a025b88..00000000
--- a/middleware/tokencheckmiddleware.php
+++ /dev/null
@@ -1,172 +0,0 @@
-<?php
-/**
- * ownCloud - galleryplus
- *
- * This file is licensed under the Affero General Public License version 3 or
- * later. See the COPYING file.
- *
- * @author Olivier Paroz <owncloud@interfasys.ch>
- * @author Bernhard Posselt <dev@bernhard-posselt.com>
- *
- * @copyright Olivier Paroz 2014-2015
- * @copyright Bernhard Posselt 2012-2015
- */
-
-namespace OCA\GalleryPlus\Middleware;
-
-use OCP\IRequest;
-use OCP\IURLGenerator;
-
-use OCP\AppFramework\Http;
-use OCP\AppFramework\Utility\IControllerMethodReflector;
-
-use OCA\GalleryPlus\Service\EnvironmentService;
-use OCA\GalleryPlus\Service\ServiceException;
-use OCA\GalleryPlus\Utility\SmarterLogger;
-
-
-/**
- * Checks that we have a valid token linked to a valid resource and that the
- * user is authorised to access it
- *
- * @package OCA\GalleryPlus\Middleware
- */
-class TokenCheckMiddleware extends CheckMiddleware {
-
-	/**
-	 * @type EnvironmentService
-	 */
-	private $environmentService;
-	/**
-	 * @type IControllerMethodReflector
-	 */
-	protected $reflector;
-
-	/***
-	 * Constructor
-	 *
-	 * @param string $appName
-	 * @param IRequest $request
-	 * @param EnvironmentService $environmentService
-	 * @param IControllerMethodReflector $reflector
-	 * @param IURLGenerator $urlGenerator
-	 * @param SmarterLogger $logger
-	 */
-	public function __construct(
-		$appName,
-		IRequest $request,
-		EnvironmentService $environmentService,
-		IControllerMethodReflector $reflector,
-		IURLGenerator $urlGenerator,
-		SmarterLogger $logger
-	) {
-		parent::__construct(
-			$appName,
-			$request,
-			$urlGenerator,
-			$logger
-		);
-
-		$this->environmentService = $environmentService;
-		$this->reflector = $reflector;
-	}
-
-	/**
-	 * Checks that we have a valid token linked to a valid resource and that the
-	 * user is authorised to access it
-	 *
-	 * Inspects the controller method annotations and if PublicPage is found
-	 * it checks that we have token and an optional password giving access to a
-	 * valid resource
-	 *
-	 * The check is not performed on "guest" pages which don't require a token
-	 *
-	 * @inheritDoc
-	 */
-	public function beforeController($controller, $methodName) {
-		$token = $this->request->getParam('token');
-		$password = $this->request->getParam('password');
-		/*// This needs to be done here as the Dispatcher does not call our reflector
-		$this->reflector->reflect($controller, $methodName);*/
-		$isPublicPage = $this->reflector->hasAnnotation('PublicPage');
-		$isGuest = $this->reflector->hasAnnotation('Guest');
-
-		if ($isPublicPage && !$isGuest) {
-			if (!$token) {
-				$this->noTokenFound();
-			} else { // We have a token
-				// Let's see if it's linked to a valid resource
-				$this->checkToken($token);
-				// Let's see if the user needs to provide a password
-				$this->checkAuthorisation($password);
-				// Let's see if we can set up the environment for the controller
-				$this->setupTokenBasedEnv();
-			}
-		}
-	}
-
-	/**
-	 * Throws an exception because no token was provided
-	 *
-	 * @throws CheckException
-	 */
-	private function noTokenFound() {
-		throw new CheckException(
-			"Can't access a public resource without a token",
-			Http::STATUS_NOT_FOUND
-		);
-	}
-
-	/**
-	 * Makes sure we have a valid token, linked to a valid resource
-	 *
-	 * @param string $token
-	 *
-	 * @throws CheckException
-	 */
-	private function checkToken($token) {
-		try {
-			$this->environmentService->checkToken($token);
-		} catch (ServiceException $exception) {
-			throw new CheckException(
-				$exception->getMessage(),
-				$exception->getCode()
-			);
-		}
-	}
-
-	/**
-	 * Checks if a password is required or if the one supplied is working
-	 *
-	 * @param $password
-	 *
-	 * @throws CheckException
-	 */
-	private function checkAuthorisation($password) {
-		try {
-			$this->environmentService->checkAuthorisation($password);
-		} catch (ServiceException $exception) {
-			throw new CheckException(
-				$exception->getMessage(),
-				$exception->getCode()
-			);
-		}
-	}
-
-	/**
-	 * Sets up the environment based on the received token
-	 *
-	 * @throws CheckException
-	 */
-	private function setupTokenBasedEnv() {
-		try {
-			$this->environmentService->setupTokenBasedEnv();
-		} catch (ServiceException $exception) {
-			throw new CheckException(
-				$exception->getMessage(),
-				$exception->getCode()
-			);
-		}
-	}
-
-}
\ No newline at end of file
diff --git a/preview/preview.php b/preview/preview.php
index 19fb83ed..feff4a45 100644
--- a/preview/preview.php
+++ b/preview/preview.php
@@ -15,16 +15,15 @@ namespace OCA\GalleryPlus\Preview;
 use OCP\IConfig;
 use OCP\Image;
 use OCP\Files\File;
+use OCP\IPreview;
 use OCP\Template;
 
-use OCP\AppFramework\Http;
-
 use OCA\GalleryPlus\Utility\SmarterLogger;
 
 /**
  * Generates previews
  *
- * @todo On OC8.1, replace \OC\Preview with OC::$server->getPreviewManager()
+ * @todo On OC8.1, replace \OC\Preview with IPreview
  *
  * @package OCA\GalleryPlus\Preview
  */
@@ -35,13 +34,17 @@ class Preview {
 	 */
 	private $dataDir;
 	/**
+	 * @type mixed
+	 */
+	private $previewManager;
+	/**
 	 * @type SmarterLogger
 	 */
 	private $logger;
 	/**
 	 * @type string
 	 */
-	private $owner;
+	private $userId;
 	/**
 	 * @type \OC\Preview
 	 */
@@ -54,131 +57,60 @@ class Preview {
 	 * @type int[]
 	 */
 	private $dims;
-
+	/**
+	 * @type bool
+	 */
+	private $success = true;
 
 	/**
 	 * Constructor
 	 *
 	 * @param IConfig $config
+	 * @param IPreview $previewManager
 	 * @param SmarterLogger $logger
 	 */
 	public function __construct(
 		IConfig $config,
+		IPreview $previewManager,
 		SmarterLogger $logger
 	) {
 		$this->dataDir = $config->getSystemValue('datadirectory');
+		$this->previewManager = $previewManager;
 		$this->logger = $logger;
 	}
 
 	/**
-	 * Initialises the object
-	 *
-	 * @fixme Private API, but can't use the PreviewManager yet as it's incomplete
-	 *
-	 * @param string $owner
-	 * @param File $file
-	 * @param string $imagePathFromFolder
-	 */
-	public function setupView($owner, $file, $imagePathFromFolder) {
-		$this->owner = $owner;
-		$this->file = $file;
-		$this->preview = new \OC\Preview($owner, 'files', $imagePathFromFolder);
-	}
-
-	/**
-	 * Decides if we should download the file instead of generating a preview
-	 *
-	 * @param bool $animatedPreview
-	 * @param bool $download
-	 *
-	 * @return bool
-	 */
-	public function previewRequired($animatedPreview, $download) {
-		$mime = $this->file->getMimeType();
-
-		if ($mime === 'image/svg+xml') {
-			return $this->isSvgPreviewRequired();
-		}
-		if ($mime === 'image/gif') {
-			return $this->isGifPreviewRequired($animatedPreview);
-		}
-
-		return !$download;
-	}
-
-	/**
-	 * Decides if we should download the SVG or generate a preview
-	 *
-	 * SVGs are downloaded if the SVG converter is disabled
-	 * Files of any media type are downloaded if requested by the client
-	 *
-	 * @return bool
-	 */
-	private function isSvgPreviewRequired() {
-		if (!$this->preview->isMimeSupported('image/svg+xml')) {
-			return false;
-		}
-
-		return true;
-	}
-
-	/**
-	 * Decides if we should download the GIF or generate a preview
-	 *
-	 * GIFs are downloaded if they're animated and we want to show
-	 * animations
+	 * Returns true if the passed mime type is supported
 	 *
-	 * @param bool $animatedPreview
+	 * @param string $mimeType
 	 *
-	 * @return bool
+	 * @return boolean
 	 */
-	private function isGifPreviewRequired($animatedPreview) {
-		$animatedGif = $this->isGifAnimated();
-
-		if ($animatedPreview && $animatedGif) {
-			return false;
-		}
-
-		return true;
+	public function isMimeSupported($mimeType = '*') {
+		return $this->previewManager->isMimeSupported($mimeType);
 	}
 
 	/**
-	 * Tests if a GIF is animated
+	 * Initialises the view which will be used to access files and generate previews
 	 *
-	 * An animated gif contains multiple "frames", with each frame having a
-	 * header made up of:
-	 *    * a static 4-byte sequence (\x00\x21\xF9\x04)
-	 *    * 4 variable bytes
-	 *    * a static 2-byte sequence (\x00\x2C) (Photoshop uses \x00\x21)
-	 *
-	 * We read through the file until we reach the end of the file, or we've
-	 * found at least 2 frame headers
-	 *
-	 * @link http://php.net/manual/en/function.imagecreatefromgif.php#104473
+	 * @fixme Private API, but can't use the PreviewManager yet as it's incomplete
 	 *
-	 * @return bool
+	 * @param string $userId
+	 * @param File $file
+	 * @param string $imagePathFromFolder
 	 */
-	private function isGifAnimated() {
-		$fileHandle = $this->file->fopen('rb');
-		$count = 0;
-		while (!feof($fileHandle) && $count < 2) {
-			$chunk = fread($fileHandle, 1024 * 100); //read 100kb at a time
-			$count += preg_match_all(
-				'#\x00\x21\xF9\x04.{4}\x00(\x2C|\x21)#s', $chunk, $matches
-			);
-		}
-
-		fclose($fileHandle);
-
-		return $count > 1;
+	public function setupView($userId, $file, $imagePathFromFolder) {
+		$this->userId = $userId;
+		$this->file = $file;
+		$this->preview = new \OC\Preview($userId, 'files', $imagePathFromFolder);
 	}
 
 	/**
 	 * Returns a preview based on OC's preview class and our custom methods
 	 *
-	 * We don't throw an exception when the preview generator fails,
-	 * instead, until the Preview class is fixed, we send the mime
-	 * icon along with a 415 error code.
+	 * We check that the preview returned by the Preview class can be used by
+	 * the browser. If not, we send the mime icon and change the status code so
+	 * that the client knows that the process has failed.
 	 *
 	 * @fixme setKeepAspect is missing from public interface.
 	 *     https://github.com/owncloud/core/issues/12772
@@ -196,13 +128,11 @@ class Preview {
 			if ($maxX === 200) { // Only fixing the square thumbnails
 				$previewData = $this->previewValidator();
 			}
-			$perfectPreview = ['preview' => $previewData, 'status' => Http::STATUS_OK];
+			$perfectPreview = ['preview' => $previewData];
 		} else {
 			$this->logger->debug("[PreviewService] ERROR! Did not get a preview");
-			$perfectPreview = [
-				'preview' => $this->getMimeIcon(),
-				'status'  => Http::STATUS_UNSUPPORTED_MEDIA_TYPE
-			];
+			$perfectPreview = ['preview' => $this->getMimeIcon()];
+			$this->success = false;
 		}
 		$perfectPreview['mimetype'] = 'image/png'; // Previews are always sent as PNG
 
@@ -210,6 +140,15 @@ class Preview {
 	}
 
 	/**
+	 * Returns true if the preview was successfully generated
+	 *
+	 * @return bool
+	 */
+	public function isPreviewValid() {
+		return $this->success;
+	}
+
+	/**
 	 * Asks core for a preview based on our criteria
 	 *
 	 * @todo Need to read scaling setting from settings
@@ -217,8 +156,6 @@ class Preview {
 	 * @param bool $keepAspect
 	 *
 	 * @return \OC_Image
-	 *
-	 * @throws \Exception
 	 */
 	private function getPreviewFromCore($keepAspect) {
 		$this->logger->debug("[PreviewService] Generating a new preview");
@@ -228,6 +165,8 @@ class Preview {
 		$this->preview->setScalingUp(false);
 		$this->preview->setKeepAspect($keepAspect);
 
+		//$this->logger->debug("[PreviewService] preview {preview}", ['preview' => $this->preview]);
+
 		return $this->preview->getPreview();
 	}
 
@@ -235,9 +174,9 @@ class Preview {
 	 * Makes sure we return previews of the asked dimensions and fix the cache
 	 * if necessary
 	 *
-	 * The Preview class of OC7 sometimes return previews which are either
-	 * wider or smaller than the asked dimensions. This happens when one of the
-	 * original dimension is smaller than what is asked for
+	 * The Preview class sometimes return previews which are either wider or
+	 * smaller than the asked dimensions. This happens when one of the original
+	 * dimension is smaller than what is asked for
 	 *
 	 * @return resource
 	 */
@@ -327,7 +266,7 @@ class Preview {
 	 * @return mixed
 	 */
 	private function fixPreviewCache($fixedPreview) {
-		$owner = $this->owner;
+		$owner = $this->userId;
 		$file = $this->file;
 		$preview = $this->preview;
 		$fixedPreviewObject = new Image($fixedPreview);
@@ -360,7 +299,7 @@ class Preview {
 		$iconData = new Image();
 
 		$image = $this->dataDir . '/../' . Template::mimetype_icon($mime);
-		// Alternative
+		// Alternative which does not exist yet
 		//$image = $this->serverRoot() . Template::mimetype_icon($mime);
 
 		$iconData->loadFromFile($image);
diff --git a/service/base64encode.php b/service/base64encode.php
new file mode 100644
index 00000000..c29f6220
--- /dev/null
+++ b/service/base64encode.php
@@ -0,0 +1,42 @@
+<?php
+/**
+ * ownCloud - galleryplus
+ *
+ * This file is licensed under the Affero General Public License version 3 or
+ * later. See the COPYING file.
+ *
+ * @author Olivier Paroz <owncloud@interfasys.ch>
+ *
+ * @copyright Olivier Paroz 2015
+ */
+
+namespace OCA\GalleryPlus\Service;
+
+/**
+ * Base64 encoding utility method
+ *
+ * @package OCA\GalleryPlus\Service
+ */
+trait Base64Encode {
+
+	/**
+	 * Returns base64 encoded data of a preview
+	 *
+	 * Using base64_encode for files which are downloaded
+	 * (cached Thumbnails, SVG, GIFs) and using __toStrings
+	 * for the previews which are instances of \OC_Image
+	 *
+	 * @param \OC_Image|string $previewData
+	 *
+	 * @return \OC_Image|string
+	 */
+	protected function encode($previewData) {
+		if ($previewData instanceof \OC_Image) {
+			$previewData = (string)$previewData;
+		} else {
+			$previewData = base64_encode($previewData);
+		}
+
+		return $previewData;
+	}
+}
\ No newline at end of file
diff --git a/service/downloadservice.php b/service/downloadservice.php
new file mode 100644
index 00000000..77cf9219
--- /dev/null
+++ b/service/downloadservice.php
@@ -0,0 +1,83 @@
+<?php
+/**
+ * ownCloud - galleryplus
+ *
+ * This file is licensed under the Affero General Public License version 3 or
+ * later. See the COPYING file.
+ *
+ * @author Olivier Paroz <owncloud@interfasys.ch>
+ *
+ * @copyright Olivier Paroz 2015
+ */
+
+namespace OCA\GalleryPlus\Service;
+
+use OCP\Files\File;
+
+use OCA\GalleryPlus\Environment\Environment;
+use OCA\GalleryPlus\Environment\NotFoundEnvException;
+use OCA\GalleryPlus\Utility\SmarterLogger;
+
+/**
+ * Prepares the file to download
+ *
+ * @package OCA\GalleryPlus\Service
+ */
+class DownloadService extends Service {
+
+	use Base64Encode;
+
+	/**
+	 * @type Environment
+	 */
+	private $environment;
+
+	/**
+	 * Constructor
+	 *
+	 * @param string $appName
+	 * @param Environment $environment
+	 * @param SmarterLogger $logger
+	 */
+	public function __construct(
+		$appName,
+		Environment $environment,
+		SmarterLogger $logger
+	) {
+		parent::__construct($appName, $logger);
+
+		$this->environment = $environment;
+	}
+
+	/**
+	 * Downloads the requested file
+	 *
+	 * @param string $image
+	 * @param bool $base64Encode
+	 *
+	 * @return array
+	 */
+	public function downloadFile($image, $base64Encode = false) {
+		$file = null;
+		try {
+			/** @type File $file */
+			$file = $this->environment->getResourceFromPath($image);
+		} catch (NotFoundEnvException $exception) {
+			$this->logAndThrowNotFound($exception->getMessage());
+		}
+		$this->logger->debug("[DownloadService] File to Download: {file}");
+		$download = [
+			'path'     => $image,
+			'preview'  => $file->getContent(),
+			'mimetype' => $file->getMimeType(),
+			'status'   => Service::STATUS_OK
+		];
+
+		if ($base64Encode) {
+			$download['preview'] = $this->encode($download['preview']);
+		}
+
+		return $download;
+	}
+
+}
\ No newline at end of file
diff --git a/service/environmentservice.php b/service/environmentservice.php
deleted file mode 100644
index fe264ae4..00000000
--- a/service/environmentservice.php
+++ /dev/null
@@ -1,385 +0,0 @@
-<?php
-/**
- * ownCloud - galleryplus
- *
- * This file is licensed under the Affero General Public License version 3 or
- * later. See the COPYING file.
- *
- * @author Olivier Paroz <owncloud@interfasys.ch>
- * @author Authors of \OCA\Files_Sharing\Helper
- *
- * @copyright Olivier Paroz 2014-2015
- * @copyright Authors of \OCA\Files_Sharing\Helper 2014-2015
- */
-
-namespace OCA\GalleryPlus\Service;
-
-use OCP\Files\Folder;
-use OCP\IServerContainer;
-use OCP\IUser;
-use OCP\ISession;
-use OCP\Share;
-use OCP\IUserManager;
-use OCP\Security\IHasher;
-
-use OCP\AppFramework\Http;
-
-use OCA\GalleryPlus\Utility\SmarterLogger;
-
-/**
- * Builds the environment so that the services have access to the proper user,
- * folder and files
- *
- * @package OCA\GalleryPlus\Service
- */
-class EnvironmentService extends Service {
-
-	/**
-	 * @type string
-	 */
-	private $userId;
-	/**
-	 * @type Folder|null
-	 */
-	private $userFolder;
-	/**
-	 * @type IUserManager
-	 */
-	private $userManager;
-	/**
-	 * @type IServerContainer
-	 */
-	private $serverContainer;
-	/**
-	 * @type IHasher
-	 * */
-	private $hasher;
-	/**
-	 * @type ISession
-	 * */
-	private $session;
-	/**
-	 * @type array
-	 */
-	private $linkItem;
-	/**
-	 * @type array
-	 */
-	private $origShareData = [];
-
-	/**
-	 * @param string $appName
-	 * @param string|null $userId
-	 * @param Folder|null $userFolder
-	 * @param IUserManager $userManager
-	 * @param IServerContainer $serverContainer
-	 * @param IHasher $hasher
-	 * @param ISession $session
-	 * @param SmarterLogger $logger
-	 */
-	public function __construct(
-		$appName,
-		$userId,
-		$userFolder,
-		IUserManager $userManager,
-		IServerContainer $serverContainer,
-		IHasher $hasher,
-		ISession $session,
-		SmarterLogger $logger
-	) {
-		parent::__construct($appName, $logger);
-
-		$this->userId = $userId;
-		$this->userFolder = $userFolder;
-		$this->userManager = $userManager;
-		$this->serverContainer = $serverContainer;
-		$this->hasher = $hasher;
-		$this->session = $session;
-	}
-
-	/**
-	 * Validates a token to make sure its linked to a valid resource
-	 *
-	 * Logic mostly duplicated from @see \OCA\Files_Sharing\Helper
-	 * @fixme setIncognitoMode in 8.1 https://github.com/owncloud/core/pull/12912
-	 *
-	 * @param string $token
-	 */
-	public function checkToken($token) {
-		// Allows a logged in user to access public links
-		\OC_User::setIncognitoMode(true);
-
-		$linkItem = Share::getShareByToken($token, false);
-
-		$this->checkLinkItemExists($linkItem);
-		$this->checkLinkItemIsValid($linkItem, $token);
-		$this->checkItemType($linkItem);
-
-		// Checks passed, let's store the linkItem
-		$this->linkItem = $linkItem;
-	}
-
-	/**
-	 * Checks if a password is required and validates it if it is provided in
-	 * the request
-	 *
-	 * @param string $password optional password
-	 */
-	public function checkAuthorisation($password = null) {
-		$passwordRequired = isset($this->linkItem['share_with']);
-
-		if ($passwordRequired) {
-			if ($password !== null) {
-				$this->authenticate($password);
-			} else {
-				$this->checkSession();
-			}
-		}
-	}
-
-	/**
-	 * Sets up the environment based on a token
-	 *
-	 * The token has already been vetted by checkToken via the token checking
-	 * middleware
-	 */
-	public function setupTokenBasedEnv() {
-		$linkItem = $this->linkItem;
-		// Resolves reshares down to the last real share
-		$rootLinkItem = Share::resolveReShare($linkItem);
-		$origShareOwner = $rootLinkItem['uid_owner'];
-		$user = $this->getUser($origShareOwner);
-		$origOwnerDisplayName = $user->getDisplayName();
-		// Setup FS for user
-		\OC_Util::tearDownFS(); // FIXME: Private API
-		\OC_Util::setupFS($origShareOwner); // FIXME: Private API
-		$fileSource = $linkItem['file_source'];
-		$origShareRelPath = $this->getPath($origShareOwner, $fileSource);
-
-		// Checks passed, let's store the data
-		$this->origShareData = [
-			'origShareOwner'       => $origShareOwner,
-			'origOwnerDisplayName' => $origOwnerDisplayName,
-			'origShareRelPath'     => $origShareRelPath
-		];
-	}
-
-	/**
-	 * Returns an array with details about the environment
-	 *
-	 * @return array various environment variables
-	 */
-	public function getEnv() {
-		$linkItem = $this->linkItem;
-
-		if (isset($linkItem)) {
-			$env = $this->getTokenBasedEnv($linkItem);
-		} else {
-			$env = [
-				'owner'        => $this->userId,
-				'relativePath' => '/',
-				'folder'       => $this->userFolder,
-			];
-		}
-
-		return $env;
-	}
-
-	/**
-	 * Returns the environment for a token
-	 *
-	 * @param $linkItem
-	 *
-	 * @return array
-	 */
-	private function getTokenBasedEnv($linkItem) {
-		$origShareOwner = $this->origShareData['origShareOwner'];
-		$origShareRelPath = $this->origShareData['origShareRelPath'];
-		// Displayed in the top right corner of the gallery
-		$origOwnerDisplayName = $this->origShareData['origOwnerDisplayName'];
-
-		$shareOwner = $linkItem['uid_owner'];
-		$folder = $this->serverContainer->getUserFolder($shareOwner);
-
-		$albumName = trim($linkItem['file_target'], '//');
-
-		return [
-			'owner'                    => $shareOwner,
-			'relativePath'             => $origShareRelPath . '/',
-			'folder'                   => $folder,
-			'albumName'                => $albumName,
-			'originalShareOwner'       => $origShareOwner,
-			'originalOwnerDisplayName' => $origOwnerDisplayName,
-		];
-	}
-
-	/**
-	 * Makes sure that the token exists
-	 *
-	 * @param bool|array $linkItem
-	 */
-	private function checkLinkItemExists($linkItem) {
-		if ($linkItem === false
-			|| ($linkItem['item_type'] !== 'file'
-				&& $linkItem['item_type'] !== 'folder')
-		) {
-			$message = 'Passed token parameter is not valid';
-			$this->kaBoom($message, Http::STATUS_BAD_REQUEST);
-		}
-	}
-
-	/**
-	 * Makes sure that the token contains all the information that we need
-	 *
-	 * @param array $linkItem
-	 * @param string $token
-	 */
-	private function checkLinkItemIsValid($linkItem, $token) {
-		if (!isset($linkItem['uid_owner'])
-			|| !isset($linkItem['file_source'])
-		) {
-			$message =
-				'Passed token seems to be valid, but it does not contain all necessary information . ("'
-				. $token . '")';
-			$this->kaBoom($message, Http::STATUS_NOT_FOUND);
-		}
-	}
-
-	/**
-	 * Makes sure an item type was set for that token
-	 *
-	 * @param array $linkItem
-	 */
-	private function checkItemType($linkItem) {
-		if (!isset($linkItem['item_type'])) {
-			$message = 'No item type set for share id: ' . $linkItem['id'];
-			$this->kaBoom($message, Http::STATUS_NOT_FOUND);
-		}
-	}
-
-	/**
-	 * Authenticate link item with the given password
-	 * or with the session if no password was given.
-	 *
-	 * @fixme Migrate old hashes to new hash format
-	 * Due to the fact that there is no reasonable functionality to update the password
-	 * of an existing share no migration is yet performed there.
-	 * The only possibility is to update the existing share which will result in a new
-	 * share ID and is a major hack.
-	 *
-	 * In the future the migration should be performed once there is a proper method
-	 * to update the share's password. (for example `$share->updatePassword($password)`
-	 * @link https://github.com/owncloud/core/issues/10671
-	 *
-	 * @param string $password
-	 *
-	 * @return bool true if authorized, an exception is raised otherwise
-	 *
-	 * @throws ServiceException
-	 */
-	private function authenticate($password) {
-		$linkItem = $this->linkItem;
-
-		if ($linkItem['share_type'] == Share::SHARE_TYPE_LINK) {
-			$this->checkPassword($password);
-		} else {
-			$this->kaBoom(
-				'Unknown share type ' . $linkItem['share_type'] . ' for share id '
-				. $linkItem['id'], Http::STATUS_NOT_FOUND
-			);
-		}
-
-		return true;
-	}
-
-	/**
-	 * Validates the given password
-	 *
-	 * @param string $password
-	 *
-	 * @throws ServiceException
-	 */
-	private function checkPassword($password) {
-		$linkItem = $this->linkItem;
-		$newHash = '';
-		if ($this->hasher->verify($password, $linkItem['share_with'], $newHash)) {
-
-			// Save item id in session for future requests
-			$this->session->set('public_link_authenticated', $linkItem['id']);
-			if (!empty($newHash)) {
-				// For future use
-			}
-		} else {
-			$this->kaBoom("Wrong password", Http::STATUS_UNAUTHORIZED);
-		}
-	}
-
-	/**
-	 * Makes sure the user is already properly authenticated when a password is required and none
-	 * was provided
-	 *
-	 * @throws ServiceException
-	 */
-	private function checkSession() {
-		// not authenticated ?
-		if (!$this->session->exists('public_link_authenticated')
-			|| $this->session->get('public_link_authenticated') !== $this->linkItem['id']
-		) {
-			$this->kaBoom("Missing password", Http::STATUS_UNAUTHORIZED);
-		}
-	}
-
-	/**
-	 * Returns an instance of the user
-	 *
-	 * @param string $origShareOwner the user the share belongs to
-	 *
-	 * @return IUser an instance of the user
-	 */
-	private function getUser($origShareOwner) {
-		$user = null;
-
-		if (isset($origShareOwner)) {
-			$user = $this->userManager->get($origShareOwner);
-		}
-		if ($user === null) {
-			$this->kaBoom('Could not find user', Http::STATUS_NOT_FOUND);
-		}
-
-		return $user;
-	}
-
-	/**
-	 * Returns the path the token gives access to
-	 *
-	 * getPath() on the file produces a path like:
-	 * '/owner/files/my_folder/my_sub_folder'
-	 *
-	 * So we substract the path to the folder, giving us a relative path
-	 * '/my_folder/my_sub_folder'
-	 *
-	 * @param string $origShareOwner
-	 * @param int $fileSource
-	 *
-	 * @return string the path, relative to the folder
-	 */
-	private function getPath($origShareOwner, $fileSource) {
-		$folder = $this->serverContainer->getUserFolder($origShareOwner);
-		$resource = $this->getResourceFromId($folder, $fileSource);
-
-		$origSharePath = $resource->getPath();
-		$folderPath = $folder->getPath();
-		$origShareRelPath = str_replace($folderPath, '', $origSharePath);
-
-		/*$this->logger->debug(
-			'Full Path {origSharePath}, relative path {origShareRelPath}',
-			[
-				'origSharePath'    => $origSharePath,
-				'origShareRelPath' => $origShareRelPath
-			]
-		);*/
-
-		return $origShareRelPath;
-	}
-
-}
\ No newline at end of file
diff --git a/service/infoservice.php b/service/infoservice.php
index 40b044d6..0e8d82ee 100644
--- a/service/infoservice.php
+++ b/service/infoservice.php
@@ -14,9 +14,6 @@ namespace OCA\GalleryPlus\Service;
 
 use OCP\Files\Folder;
 use OCP\Files\File;
-use OCP\IPreview;
-
-use OCP\AppFramework\Http;
 
 use OCA\GalleryPlus\Utility\SmarterLogger;
 
@@ -30,23 +27,15 @@ use OCA\GalleryPlus\Utility\SmarterLogger;
 class InfoService extends Service {
 
 	/**
-	 * @type Folder|null
-	 */
-	private $userFolder;
-	/**
-	 * @type EnvironmentService
-	 */
-	private $environmentService;
-	/**
 	 * @type mixed
 	 */
-	private $previewManager;
+	private $previewService;
 	/**
 	 * @todo This hard-coded array could be replaced by admin settings
 	 *
 	 * @type string[]
 	 */
-	private static $baseMimeTypes = [
+	private $baseMimeTypes = [
 		'image/png',
 		'image/jpeg',
 		'image/gif',
@@ -64,7 +53,7 @@ class InfoService extends Service {
 	 *
 	 * @type string[]
 	 */
-	private static $slideshowMimeTypes = [
+	private $slideshowMimeTypes = [
 		'application/font-sfnt',
 		'application/x-font',
 	];
@@ -73,47 +62,18 @@ class InfoService extends Service {
 	 * Constructor
 	 *
 	 * @param string $appName
-	 * @param Folder|null $userFolder
-	 * @param EnvironmentService $environmentService
 	 * @param SmarterLogger $logger
-	 * @param IPreview $previewManager
+	 * @param PreviewService $previewManager
 	 */
 	public function __construct(
 		$appName,
-		$userFolder,
-		EnvironmentService $environmentService,
-		SmarterLogger $logger,
-		IPreview $previewManager
+		PreviewService $previewManager,
+		SmarterLogger $logger
+
 	) {
 		parent::__construct($appName, $logger);
 
-		$this->userFolder = $userFolder;
-		$this->environmentService = $environmentService;
-		$this->previewManager = $previewManager;
-	}
-
-	/**
-	 * Returns information about an album, based on its path
-	 *
-	 * Used to see if we have access to the folder or not
-	 *
-	 * @param string $albumpath
-	 *
-	 * @return array<string,int>|false information about the given path
-	 */
-	public function getAlbumInfo($albumpath) {
-		$userFolder = $this->userFolder;
-		$nodeInfo = false;
-
-		if ($userFolder !== null) {
-			$nodeInfo = $this->getNodeInfo($userFolder, $albumpath);
-		} else {
-			$message = "Could not access the user's folder";
-			$code = Http::STATUS_NOT_FOUND;
-			$this->kaBoom($message, $code);
-		}
-
-		return $nodeInfo;
+		$this->previewService = $previewManager;
 	}
 
 	/**
@@ -127,16 +87,15 @@ class InfoService extends Service {
 	 */
 	public function getSupportedMimes($slideshow = true) {
 		$supportedMimes = [];
-		$wantedMimes = self::$baseMimeTypes;
+		$wantedMimes = $this->baseMimeTypes;
 
 		if ($slideshow) {
-			$wantedMimes = array_merge($wantedMimes, self::$slideshowMimeTypes);
+			$wantedMimes = array_merge($wantedMimes, $this->slideshowMimeTypes);
 		}
 
 		foreach ($wantedMimes as $wantedMime) {
 			// Let's see if a preview of files of that media type can be generated
-			$preview = $this->previewManager;
-			if ($preview->isMimeSupported($wantedMime)) {
+			if ($this->previewService->isMimeSupported($wantedMime)) {
 				$supportedMimes[] = $wantedMime; // We add it to the list of supported media types
 			}
 		}
@@ -148,49 +107,21 @@ class InfoService extends Service {
 	}
 
 	/**
-	 * This returns the list of all images which can be shown
+	 * This returns the list of all images which can be shown starting from the given folder
 	 *
-	 * For private galleries, it returns all images
-	 * For public galleries, it starts from the folder the link gives access to
+	 * @param array $folderData
 	 *
 	 * @return array all the images we could find
 	 */
-	public function getImages() {
-		$folderData = $this->getImagesFolder();
-
-		$imagesFolder = $folderData['imagesFolder'];
-		$images = $this->searchByMime($imagesFolder);
-
+	public function getImages($folderData) {
+		$images = $this->searchByMime($folderData['imagesFolder']);
 		$fromRootToFolder = $folderData['fromRootToFolder'];
-		$result = $this->fixImagePath($images, $fromRootToFolder);
 
-		/*$this->logger->debug("Images array: {images}",['images' => $result]);*/
+		$result = $this->prepareImagesArray($images, $fromRootToFolder);
 
-		return $result;
-	}
+		//$this->logger->debug("Images array: {images}", ['images' => $result]);
 
-	/**
-	 * Returns the folder where we need to look for files, as well as the path
-	 * starting from it and going up to the user's root folder
-	 *
-	 * @return array<string,Folder|string>
-	 */
-	private function getImagesFolder() {
-		$env = $this->environmentService->getEnv();
-		$pathRelativeToFolder = $env['relativePath'];
-		/** @type Folder $folder */
-		$folder = $env['folder'];
-		$folderPath = $folder->getPath();
-		/** @type Folder $imagesFolder */
-		$imagesFolder = $this->getResourceFromPath($folder, $pathRelativeToFolder);
-		$fromRootToFolder = $folderPath . $pathRelativeToFolder;
-
-		$folderData = [
-			'imagesFolder'     => $imagesFolder,
-			'fromRootToFolder' => $fromRootToFolder,
-		];
-
-		return $folderData;
+		return $result;
 	}
 
 	/**
@@ -225,6 +156,7 @@ class InfoService extends Service {
 	 * We remove the part which goes from the user's root to the current
 	 * folder and we also remove the current folder for public galleries
 	 *
+	 * @todo Test this on OC8
 	 * On OC7, we fix searchByMime which returns images from the rubbish bin...
 	 * https://github.com/owncloud/core/issues/4903
 	 *
@@ -244,15 +176,13 @@ class InfoService extends Service {
 	 *
 	 * @return array
 	 */
-	private function fixImagePath($images, $fromRootToFolder) {
+	private function prepareImagesArray($images, $fromRootToFolder) {
 		$result = [];
 		/** @type File $image */
 		foreach ($images as $image) {
 			$imagePath = $image->getPath();
 			$mimeType = $image->getMimetype();
-			$fixedPath = str_replace(
-				$fromRootToFolder, '', $imagePath
-			);
+			$fixedPath = str_replace($fromRootToFolder, '', $imagePath);
 			if (substr($fixedPath, 0, 9) === "_trashbin") {
 				continue;
 			}
diff --git a/service/notfoundserviceexception.php b/service/notfoundserviceexception.php
new file mode 100644
index 00000000..298f7bbd
--- /dev/null
+++ b/service/notfoundserviceexception.php
@@ -0,0 +1,28 @@
+<?php
+/**
+ * ownCloud - galleryplus
+ *
+ * This file is licensed under the Affero General Public License version 3 or
+ * later. See the COPYING file.
+ *
+ * @author Olivier Paroz <owncloud@interfasys.ch>
+ *
+ * @copyright Olivier Paroz 2014-2015
+ */
+
+namespace OCA\GalleryPlus\Service;
+
+/**
+ * Thrown when the service cannot reply to a request
+ */
+class NotFoundServiceException extends ServiceException {
+
+	/**
+	 * Constructor
+	 *
+	 * @param string $msg the message contained in the exception
+	 */
+	public function __construct($msg) {
+		parent::__construct($msg);
+	}
+}
\ No newline at end of file
diff --git a/service/previewservice.php b/service/previewservice.php
index 23b1c9d4..b8d5ba85 100644
--- a/service/previewservice.php
+++ b/service/previewservice.php
@@ -6,19 +6,16 @@
  * later. See the COPYING file.
  *
  * @author Olivier Paroz <owncloud@interfasys.ch>
- * @author Robin Appelman <icewind@owncloud.com>
  *
  * @copyright Olivier Paroz 2014-2015
- * @copyright Robin Appelman 2012-2015
  */
 
 namespace OCA\GalleryPlus\Service;
 
 use OCP\Files\File;
 
-use OCP\AppFramework\Http;
-
-use OCA\GalleryPlus\Http\ImageResponse;
+use OCA\GalleryPlus\Environment\Environment;
+use OCA\GalleryPlus\Environment\NotFoundEnvException;
 use OCA\GalleryPlus\Preview\Preview;
 use OCA\GalleryPlus\Utility\SmarterLogger;
 
@@ -29,112 +26,83 @@ use OCA\GalleryPlus\Utility\SmarterLogger;
  */
 class PreviewService extends Service {
 
+	use Base64Encode;
+
 	/**
-	 * @type EnvironmentService
+	 * @type Environment
 	 */
-	private $environmentService;
+	private $environment;
 	/**
 	 * @type Preview
 	 */
 	private $previewManager;
-	/**
-	 * @type bool
-	 */
-	private $animatedPreview = true;
-	/**
-	 * @type bool
-	 */
-	private $keepAspect = true;
-	/**
-	 * @type bool
-	 */
-	private $base64Encode = false;
-	/**
-	 * @type bool
-	 */
-	private $download = false;
 
 	/**
 	 * Constructor
 	 *
 	 * @param string $appName
-	 * @param EnvironmentService $environmentService
-	 * @param SmarterLogger $logger
+	 * @param Environment $environment
 	 * @param Preview $previewManager
+	 * @param SmarterLogger $logger
 	 */
 	public function __construct(
 		$appName,
-		EnvironmentService $environmentService,
-		SmarterLogger $logger,
-		Preview $previewManager
+		Environment $environment,
+		Preview $previewManager,
+		SmarterLogger $logger
 	) {
 		parent::__construct($appName, $logger);
 
-		$this->environmentService = $environmentService;
+		$this->environment = $environment;
 		$this->previewManager = $previewManager;
 	}
 
 	/**
-	 * @param string $image
-	 * @param int $maxX
-	 * @param int $maxY
-	 * @param bool $keepAspect
-	 *
-	 * @return array<string,\OC_Image|string> preview data
-	 */
-	public function createThumbnails($image, $maxX, $maxY, $keepAspect) {
-		$this->animatedPreview = false;
-		$this->base64Encode = true;
-		$this->keepAspect = $keepAspect;
-
-		return $this->createPreview($image, $maxX, $maxY);
-	}
-
-
-	/**
-	 * Sends either a large preview of the requested file or the original file
-	 * itself
+	 * Returns true if the passed mime type is supported
 	 *
-	 * @param string $image
-	 * @param int $maxX
-	 * @param int $maxY
+	 * @param string $mimeType
 	 *
-	 * @return ImageResponse
+	 * @return boolean
 	 */
-	public function showPreview($image, $maxX, $maxY) {
-		$preview = $this->createPreview($image, $maxX, $maxY);
-
-		return new ImageResponse($preview, $preview['status']);
+	public function isMimeSupported($mimeType = '*') {
+		return $this->previewManager->isMimeSupported($mimeType);
 	}
 
 	/**
-	 * Downloads the requested file
+	 * Decides if we should download the file instead of generating a preview
 	 *
 	 * @param string $image
+	 * @param bool $animatedPreview
 	 *
-	 * @return ImageResponse
+	 * @return bool
 	 */
-	public function downloadPreview($image) {
-		$this->download = true;
+	public function isPreviewRequired($image, $animatedPreview) {
+		$file = null;
+		try {
+			/** @type File $file */
+			$file = $this->environment->getResourceFromPath($image);
+
+		} catch (NotFoundEnvException $exception) {
+			$this->logAndThrowNotFound($exception->getMessage());
+		}
+		$mime = $file->getMimeType();
+		if ($mime === 'image/svg+xml') {
+			return $this->isSvgPreviewRequired();
+		}
+		if ($mime === 'image/gif') {
+			return $this->isGifPreviewRequired($file, $animatedPreview);
+		}
 
-		return $this->showPreview($image, null, null);
+		return true;
 	}
 
 	/**
-	 * Creates an array containing everything needed to render a preview in the
-	 * browser
-	 *
-	 * If the browser can use the file as-is or if we're asked to send it
-	 * as-is, then we simply let the browser download the file, straight from
-	 * Files
+	 * Returns an array containing everything needed by the client to be able to display a preview
 	 *
-	 * Some files are base64 encoded. Explicitly for files which are downloaded
-	 * (cached Thumbnails, SVG, GIFs) and via __toStrings for the previews
-	 * which are instances of \OC_Image
-	 *
-	 * We check that the preview returned by the Preview class can be used by
-	 * the browser. If not, we send the mime icon and change the status code so
-	 * that the client knows that the process failed
+	 *    * path: the given path to the file
+	 *    * mimetype: the file's media type
+	 *    * preview: the preview's content
+	 *    * status: a code indicating whether the conversion process was successful or not
 	 *
 	 * Example logger
 	 * $this->logger->debug(
@@ -151,69 +119,100 @@ class PreviewService extends Service {
 	 * @param string $image path to the image, relative to the user folder
 	 * @param int $maxX asked width for the preview
 	 * @param int $maxY asked height for the preview
+	 * @param bool $keepAspect
+	 *
+	 * @return array <string,\OC_Image|string> preview data
+	 */
+	public function createPreview($image, $maxX = 0, $maxY = 0, $keepAspect = true) {
+		$file = null;
+		try {
+			/** @type File $file */
+			$file = $this->environment->getResourceFromPath($image);
+		} catch (NotFoundEnvException $exception) {
+			$this->logAndThrowNotFound($exception->getMessage());
+		}
+		$userId = $this->environment->getUserID();
+		$imagePathFromFolder = $this->environment->getImagePathFromFolder($image);
+		$this->previewManager->setupView($userId, $file, $imagePathFromFolder);
+
+		$preview = $this->previewManager->preparePreview($maxX, $maxY, $keepAspect);
+		$preview['path'] = $image;
+		$preview['status'] = Service::STATUS_OK;
+		if (!$this->previewManager->isPreviewValid()) {
+			$preview['status'] = Service::STATUS_UNSUPPORTED_MEDIA_TYPE;
+		}
+
+		return $preview;
+	}
+
+	/**
+	 * Decides if we should download the SVG or generate a preview
+	 *
+	 * SVGs are downloaded if the SVG converter is disabled
+	 * Files of any media type are downloaded if requested by the client
 	 *
-	 * @return array<string,\OC_Image|string> preview data
+	 * @return bool
 	 */
-	private function createPreview($image, $maxX = 0, $maxY = 0) {
-		$env = $this->environmentService->getEnv();
-		$owner = $env['owner'];
-		$folder = $env['folder'];
-		$imagePathFromFolder = $env['relativePath'] . $image;
-		/** @type File $file */
-		$file = $this->getResourceFromPath($folder, $imagePathFromFolder);
-		$this->previewManager->setupView($owner, $file, $imagePathFromFolder);
-		$previewRequired =
-			$this->previewManager->previewRequired($this->animatedPreview, $this->download);
-
-		if ($previewRequired) {
-			$perfectPreview =
-				$this->previewManager->preparePreview($maxX, $maxY, $this->keepAspect);
-		} else {
-			$perfectPreview = $this->prepareDownload($file, $image);
+	private function isSvgPreviewRequired() {
+		if (!$this->isMimeSupported('image/svg+xml')) {
+			return false;
 		}
-		$perfectPreview['preview'] = $this->base64EncodeCheck($perfectPreview['preview']);
-		$perfectPreview['path'] = $image;
 
-		return $perfectPreview;
+		return true;
 	}
 
 	/**
-	 * Returns the data needed to make a file available for download
+	 * Decides if we should download the GIF or generate a preview
+	 *
+	 * GIFs are downloaded if they're animated and we want to show
+	 * animations
 	 *
 	 * @param File $file
-	 * @param string $image
+	 * @param bool $animatedPreview
 	 *
-	 * @return array
+	 * @return bool
 	 */
-	private function prepareDownload($file, $image) {
-		$this->logger->debug("[PreviewService] Downloading file {file} as-is", ['file' => $image]);
-
-		return [
-			'preview'  => $file->getContent(),
-			'mimetype' => $file->getMimeType(),
-			'status'   => Http::STATUS_OK
-		];
+	private function isGifPreviewRequired($file, $animatedPreview) {
+		$animatedGif = $this->isGifAnimated($file);
+
+		if ($animatedPreview && $animatedGif) {
+			return false;
+		}
+
+		return true;
 	}
 
 	/**
-	 * Returns base64 encoded data of a preview
+	 * Tests if a GIF is animated
+	 *
+	 * An animated gif contains multiple "frames", with each frame having a
+	 * header made up of:
+	 *    * a static 4-byte sequence (\x00\x21\xF9\x04)
+	 *    * 4 variable bytes
+	 *    * a static 2-byte sequence (\x00\x2C) (Photoshop uses \x00\x21)
+	 *
+	 * We read through the file until we reach the end of the file, or we've
+	 * found at least 2 frame headers
 	 *
-	 * @param \OC_Image|string $previewData
+	 * @link http://php.net/manual/en/function.imagecreatefromgif.php#104473
 	 *
-	 * @return \OC_Image|string
+	 * @param File $file
+	 *
+	 * @return bool
 	 */
-	private function base64EncodeCheck($previewData) {
-		$base64Encode = $this->base64Encode;
-
-		if ($base64Encode === true) {
-			if ($previewData instanceof \OC_Image) {
-				$previewData = (string)$previewData;
-			} else {
-				$previewData = base64_encode($previewData);
-			}
+	private function isGifAnimated($file) {
+		$fileHandle = $file->fopen('rb');
+		$count = 0;
+		while (!feof($fileHandle) && $count < 2) {
+			$chunk = fread($fileHandle, 1024 * 100); //read 100kb at a time
+			$count += preg_match_all(
+				'#\x00\x21\xF9\x04.{4}\x00(\x2C|\x21)#s', $chunk, $matches
+			);
 		}
 
-		return $previewData;
+		fclose($fileHandle);
+
+		return $count > 1;
 	}
 
 }
\ No newline at end of file
diff --git a/service/service.php b/service/service.php
index 725cc015..de142dab 100644
--- a/service/service.php
+++ b/service/service.php
@@ -12,12 +12,6 @@
 
 namespace OCA\GalleryPlus\Service;
 
-use OCP\Files\Folder;
-use OCP\Files\Node;
-use OCP\Files\NotFoundException;
-
-use OCP\AppFramework\Http;
-
 use OCA\GalleryPlus\Utility\SmarterLogger;
 
 /**
@@ -27,10 +21,16 @@ use OCA\GalleryPlus\Utility\SmarterLogger;
  */
 abstract class Service {
 
+	const STATUS_OK = 200;
+	const STATUS_NOT_FOUND = 404;
+	const STATUS_UNSUPPORTED_MEDIA_TYPE = 415;
+	const STATUS_UNPROCESSABLE_ENTITY = 422;
+	const STATUS_INTERNAL_SERVER_ERROR = 500;
+
 	/**
 	 * @type string
 	 */
-	protected $appName;
+	private $appName;
 	/**
 	 * @type SmarterLogger
 	 */
@@ -42,86 +42,24 @@ abstract class Service {
 	 * @param string $appName
 	 * @param SmarterLogger $logger
 	 */
-	public function __construct($appName, SmarterLogger $logger) {
+	public function __construct(
+		$appName,
+		SmarterLogger $logger
+	) {
 		$this->appName = $appName;
 		$this->logger = $logger;
 	}
 
 	/**
-	 * Returns the resource identified by the given ID
-	 *
-	 * @param Folder $folder
-	 * @param int $resourceId
-	 *
-	 * @return Node
-	 * @throws ServiceException
-	 */
-	protected function getResourceFromId($folder, $resourceId) {
-		$resourcesArray = $folder->getById($resourceId);
-		if ($resourcesArray[0] === null) {
-			$this->kaBoom('Could not resolve linkItem', Http::STATUS_NOT_FOUND);
-		}
-
-		return $resourcesArray[0];
-	}
-
-	/**
-	 * Returns the resource located at the given path
-	 *
-	 * The path starts from the user's files folder
-	 * The resource is either a File or a Folder
-	 *
-	 * @param Folder $folder
-	 * @param string $path
-	 *
-	 * @return Node
-	 */
-	protected function getResourceFromPath($folder, $path) {
-		$nodeInfo = $this->getNodeInfo($folder, $path);
-
-		return $this->getResourceFromId($folder, $nodeInfo['fileid']);
-	}
-
-	/**
-	 * Returns the Node based on the current user's files folder and a given
-	 * path
-	 *
-	 * @param Folder $folder
-	 * @param string $path
-	 *
-	 * @return int[]|false
-	 */
-	protected function getNodeInfo($folder, $path) {
-		$nodeInfo = false;
-		try {
-			$node = $folder->get($path);
-			$nodeInfo = [
-				'fileid'      => $node->getId(),
-				'permissions' => $node->getPermissions()
-			];
-		} catch (NotFoundException $exception) {
-			$message = $exception->getMessage();
-			$code = Http::STATUS_NOT_FOUND;
-			$this->kaBoom($message, $code);
-		}
-
-		return $nodeInfo;
-	}
-
-	/**
 	 * Logs the error and raises an exception
 	 *
 	 * @param string $message
-	 * @param int $code
 	 *
 	 * @throws ServiceException
 	 */
-	protected function kaBoom($message, $code) {
-		$this->logger->error($message . ' (' . $code . ')');
+	protected function logAndThrowNotFound($message) {
+		$this->logger->error($message . ' (404)');
 
-		throw new ServiceException(
-			$message,
-			$code
-		);
+		throw new NotFoundServiceException($message);
 	}
 }
\ No newline at end of file
diff --git a/service/serviceexception.php b/service/serviceexception.php
index be78273a..81f24079 100644
--- a/service/serviceexception.php
+++ b/service/serviceexception.php
@@ -12,18 +12,19 @@
 
 namespace OCA\GalleryPlus\Service;
 
+use Exception;
+
 /**
  * Thrown when the service cannot reply to a request
  */
-class ServiceException extends \Exception {
+class ServiceException extends Exception {
 
 	/**
 	 * Constructor
 	 *
 	 * @param string $msg the message contained in the exception
-	 * @param int $code the HTTP status code
 	 */
-	public function __construct($msg, $code = 0) {
-		parent::__construct($msg, $code);
+	public function __construct($msg) {
+		parent::__construct($msg);
 	}
 }
\ No newline at end of file
diff --git a/service/thumbnailservice.php b/service/thumbnailservice.php
index 4a4980db..86922927 100644
--- a/service/thumbnailservice.php
+++ b/service/thumbnailservice.php
@@ -6,101 +6,54 @@
  * later. See the COPYING file.
  *
  * @author Olivier Paroz <owncloud@interfasys.ch>
- * @author Robin Appelman <icewind@owncloud.com>
  *
  * @copyright Olivier Paroz 2014-2015
- * @copyright Robin Appelman 2012-2015
  */
 
 namespace OCA\GalleryPlus\Service;
 
-use OCP\IEventSource;
-
+use OCA\GalleryPlus\Environment\Environment;
+use OCA\GalleryPlus\Preview\Preview;
 use OCA\GalleryPlus\Utility\SmarterLogger;
 
 /**
- * Collects and returns thumbnails for the list of images which is submitted to
+ * Creates thumbnails for the list of images which is submitted to
  * the service
  *
  * Uses EventSource to send back thumbnails as soon as they're ready
  *
  * @package OCA\GalleryPlus\Service
  */
-class ThumbnailService {
-
-	/**
-	 * @type string
-	 */
-	private $appName;
-	/**
-	 * @type SmarterLogger
-	 */
-	private $logger;
-	/**
-	 * @type IEventSource
-	 */
-	private $eventSource;
-	/**
-	 * @type PreviewService
-	 */
-	private $previewService;
-
+class ThumbnailService extends PreviewService {
 
 	/**
 	 * Constructor
 	 *
 	 * @param string $appName
+	 * @param Environment $environment
+	 * @param Preview $previewManager
 	 * @param SmarterLogger $logger
-	 * @param IEventSource $eventSource
-	 * @param PreviewService $previewService
 	 */
 	public function __construct(
 		$appName,
-		SmarterLogger $logger,
-		IEventSource $eventSource,
-		PreviewService $previewService
+		Environment $environment,
+		Preview $previewManager,
+		SmarterLogger $logger
 	) {
-		$this->appName = $appName;
-		$this->logger = $logger;
-		$this->previewService = $previewService;
-		$this->eventSource = $eventSource;
-	}
-
-	/**
-	 * Sends previews of each image contained in the $images array using
-	 * EventSource
-	 *
-	 * The data is generated by the PreviewService and is base64 encoded
-	 *
-	 * WARNING: We can't close the session here because public galleries
-	 * of encrypted files would not get their previews
-	 *
-	 * FIXME: @LukasReschke says: The exit is required here because
-	 * otherwise the AppFramework is trying to add headers as well after
-	 * dispatching the request which results in a "Cannot modify header
-	 * information" notice.
-	 * WARNING: Returning a JSON response does not work.
-	 *
-	 * @param string $images
-	 * @param bool $square
-	 * @param bool $scale
-	 */
-	public function getAlbumThumbnails($images, $square, $scale) {
-		$imagesArray = explode(';', $images);
-
-		$this->createThumbnails($imagesArray, $square, $scale);
-
-		$this->eventSource->close();
-
-		exit();
+		parent::__construct(
+			$appName,
+			$environment,
+			$previewManager,
+			$logger
+		);
 	}
 
 	/**
-	 * Asks the Thumbnail service to send us thumbnails
+	 * Creates thumbnails of asked dimensions and aspect
 	 *
-	 * Album thumnails need to be 200x200 and some will be resized by the
-	 * browser to 200x100 or 100x100.
-	 * Standard thumbnails are 400x200.
+	 *    * Album thumbnails need to be 200x200 and some will be resized by the
+	 *      browser to 200x100 or 100x100.
+	 *    * Standard thumbnails are 400x200.
 	 *
 	 * Sample logger
 	 * We can't just send previewData as it can be quite a large stream
@@ -113,21 +66,23 @@ class ThumbnailService {
 	 *              ]
 	 *            );
 	 *
-	 * @param string[] $imagesArray
+	 * @param string $image
 	 * @param bool $square
 	 * @param bool $scale
+	 *
+	 * @return array
 	 */
-	private function createThumbnails($imagesArray, $square, $scale) {
-		foreach ($imagesArray as $image) {
-			$height = 200 * $scale;
-			if ($square) {
-				$width = $height;
-			} else {
-				$width = 2 * $height;
-			}
-
-			$preview = $this->previewService->createThumbnails($image, $width, $height, !$square);
-			$this->eventSource->send('preview', $preview);
+	public function createThumbnail($image, $square, $scale) {
+		$height = 200 * $scale;
+		if ($square) {
+			$width = $height;
+		} else {
+			$width = 2 * $height;
 		}
+		$preview = $this->createPreview($image, $width, $height, !$square);
+		$preview['preview'] = $this->encode($preview['preview']);
+
+		return $preview;
 	}
+
 }
\ No newline at end of file