Move default provider registration to preview manager

1 files changed, 169 insertions, 1 deletions

diff --git a/lib/private/previewmanager.php b/lib/private/previewmanager.php
index 29c205e7309..e0179232978 100644
--- a/lib/private/previewmanager.php
+++ b/lib/private/previewmanager.php
@@ -16,6 +16,13 @@ class PreviewManager implements IPreview {
 	protected $providers = [];
 
 	/**
+	 * Constructor
+	 */
+	public function __construct() {
+		$this->registerCoreProviders();
+	}
+
+	/**
 	 * In order to improve lazy loading a closure can be registered which will be
 	 * called in case preview providers are actually requested
 	 *
@@ -26,6 +33,10 @@ class PreviewManager implements IPreview {
 	 * @return void
 	 */
 	public function registerProvider($mimeTypeRegex, \Closure $callable) {
+		if (!\OC::$server->getConfig()->getSystemValue('enable_previews', true)) {
+			return;
+		}
+
 		if (!isset($this->providers[$mimeTypeRegex])) {
 			$this->providers[$mimeTypeRegex] = [];
 		}
@@ -33,6 +44,25 @@ class PreviewManager implements IPreview {
 	}
 
 	/**
+	 * Get all providers
+	 * @return array
+	 */
+	public function getProviders() {
+		$keys = array_map('strlen', array_keys($this->providers));
+		array_multisort($keys, SORT_DESC, $this->providers);
+
+		return $this->providers;
+	}
+
+	/**
+	 * Does the manager have any providers
+	 * @return bool
+	 */
+	public function hasProviders() {
+		return !empty($this->providers);
+	}
+
+	/**
 	 * return a preview of a file
 	 *
 	 * @param string $file The path to the file where you want a thumbnail from
@@ -84,7 +114,12 @@ class PreviewManager implements IPreview {
 
 		foreach ($this->providers as $supportedMimeType => $providers) {
 			if (preg_match($supportedMimeType, $file->getMimetype())) {
-				foreach ($providers as $provider) {
+				foreach ($providers as $closure) {
+					$provider = $closure();
+					if (!($provider instanceof \OC\Preview\Provider)) {
+						continue;
+					}
+
 					/** @var $provider \OC\Preview\Provider */
 					if ($provider->isAvailable($file)) {
 						return true;
@@ -94,4 +129,137 @@ class PreviewManager implements IPreview {
 		}
 		return false;
 	}
+
+	/** @var array */
+	protected $defaultProviders;
+
+	/**
+	 * List of enabled default providers
+	 *
+	 * The following providers are enabled by default:
+	 *  - OC\Preview\Image
+	 *  - OC\Preview\MP3
+	 *  - OC\Preview\TXT
+	 *  - OC\Preview\MarkDown
+	 *
+	 * The following providers are disabled by default due to performance or privacy concerns:
+	 *  - OC\Preview\MSOfficeDoc
+	 *  - OC\Preview\MSOffice2003
+	 *  - OC\Preview\MSOffice2007
+	 *  - OC\Preview\OpenDocument
+	 *  - OC\Preview\StarOffice
+	 *  - OC\Preview\SVG
+	 *  - OC\Preview\Movie
+	 *  - OC\Preview\PDF
+	 *  - OC\Preview\TIFF
+	 *  - OC\Preview\Illustrator
+	 *  - OC\Preview\Postscript
+	 *  - OC\Preview\Photoshop
+	 *  - OC\Preview\Font
+	 *
+	 * @return array
+	 */
+	protected function getEnabledDefaultProvider() {
+		if ($this->defaultProviders !== null) {
+			return $this->defaultProviders;
+		}
+
+		$this->defaultProviders = \OC::$server->getConfig()->getSystemValue('enabledPreviewProviders', [
+			'OC\Preview\Image',
+			'OC\Preview\MP3',
+			'OC\Preview\TXT',
+			'OC\Preview\MarkDown',
+		]);
+		return $this->defaultProviders;
+	}
+
+	/**
+	 * Register the default providers (if enabled)
+	 *
+	 * @param string $class
+	 * @param string $mimeType
+	 */
+	protected function registerCoreProvider($class, $mimeType) {
+		if (in_array(trim($class, '\\'), $this->getEnabledDefaultProvider())) {
+			$this->registerProvider($mimeType, function () use ($class) {
+				return new $class([]);
+			});
+		}
+	}
+
+	/**
+	 * Register the default providers (if enabled)
+	 */
+	protected function registerCoreProviders() {
+		$this->registerCoreProvider('OC\Preview\TXT', '/text\/plain/');
+		$this->registerCoreProvider('OC\Preview\MarkDown', '/text\/(x-)?markdown/');
+		$this->registerCoreProvider('OC\Preview\Image', '/image\/(?!tiff$)(?!svg.*).*/');
+		$this->registerCoreProvider('OC\Preview\MP3', '/audio\/mpeg/');
+
+		// SVG, Office and Bitmap require imagick
+		if (extension_loaded('imagick')) {
+			$checkImagick = new \Imagick();
+
+			$imagickProviders = [
+				'SVG'	=> ['mimetype' => '/image\/svg\+xml/', 'class' => '\OC\Preview\SVG'],
+				'TIFF'	=> ['mimetype' => '/image\/tiff/', 'class' => '\OC\Preview\TIFF'],
+				'PDF'	=> ['mimetype' => '/application\/pdf/', 'class' => '\OC\Preview\PDF'],
+				'AI'	=> ['mimetype' => '/application\/illustrator/', 'class' => '\OC\Preview\Illustrator'],
+				'PSD'	=> ['mimetype' => '/application\/x-photoshop/', 'class' => '\OC\Preview\Photoshop'],
+				'EPS'	=> ['mimetype' => '/application\/postscript/', 'class' => '\OC\Preview\Postscript'],
+				'TTF'	=> ['mimetype' => '/application\/(?:font-sfnt|x-font$)/', 'class' => '\OC\Preview\Font'],
+			];
+
+			foreach ($imagickProviders as $queryFormat => $provider) {
+				$class = $provider['class'];
+				if (!in_array(trim($class, '\\'), $this->getEnabledDefaultProvider())) {
+					continue;
+				}
+
+				if (count($checkImagick->queryFormats($queryFormat)) === 1) {
+					$this->registerCoreProvider($class, $provider['mimetype']);
+				}
+			}
+
+			if (count($checkImagick->queryFormats('PDF')) === 1) {
+				// Office previews are currently not supported on Windows
+				if (!\OC_Util::runningOnWindows() && \OC_Helper::is_function_enabled('shell_exec')) {
+					$officeFound = is_string(\OC::$server->getConfig()->getSystemValue('preview_libreoffice_path', null));
+
+					if (!$officeFound) {
+						//let's see if there is libreoffice or openoffice on this machine
+						$whichLibreOffice = shell_exec('command -v libreoffice');
+						$officeFound = !empty($whichLibreOffice);
+						if (!$officeFound) {
+							$whichOpenOffice = shell_exec('command -v openoffice');
+							$officeFound = !empty($whichOpenOffice);
+						}
+					}
+
+					if ($officeFound) {
+						$this->registerCoreProvider('\OC\Preview\MSOfficeDoc', '/application\/msword/');
+						$this->registerCoreProvider('\OC\Preview\MSOffice2003', '/application\/vnd.ms-.*/');
+						$this->registerCoreProvider('\OC\Preview\MSOffice2007', '/application\/vnd.openxmlformats-officedocument.*/');
+						$this->registerCoreProvider('\OC\Preview\OpenDocument', '/application\/vnd.oasis.opendocument.*/');
+						$this->registerCoreProvider('\OC\Preview\StarOffice', '/application\/vnd.sun.xml.*/');
+					}
+				}
+			}
+		}
+
+		// Video requires avconv or ffmpeg and is therefor
+		// currently not supported on Windows.
+		if (in_array('OC\Preview\Movie', $this->getEnabledDefaultProvider()) && !\OC_Util::runningOnWindows()) {
+			$avconvBinary = \OC_Helper::findBinaryPath('avconv');
+			$ffmpegBinary = ($avconvBinary) ? null : \OC_Helper::findBinaryPath('ffmpeg');
+
+			if ($avconvBinary || $ffmpegBinary) {
+				// FIXME // a bit hacky but didn't want to use subclasses
+				\OC\Preview\Movie::$avconvBinary = $avconvBinary;
+				\OC\Preview\Movie::$ffmpegBinary = $ffmpegBinary;
+
+				$this->registerCoreProvider('\OC\Preview\Movie', '/video\/.*/');
+			}
+		}
+	}
 }