diff options
Diffstat (limited to 'Zotlabs/Thumbs/Epubthumb.php')
| -rw-r--r-- | Zotlabs/Thumbs/Epubthumb.php | 183 |
1 files changed, 160 insertions, 23 deletions
diff --git a/Zotlabs/Thumbs/Epubthumb.php b/Zotlabs/Thumbs/Epubthumb.php index 6ebbd8933..af372e85c 100644 --- a/Zotlabs/Thumbs/Epubthumb.php +++ b/Zotlabs/Thumbs/Epubthumb.php @@ -2,60 +2,197 @@ namespace Zotlabs\Thumbs; -require_once 'library/epub-meta/epub.php'; +use DOMDocument; +use DOMElement; +use DOMXPath; +use GdImage; +use ZipArchive; /** - * @brief Thumbnail creation for epub files. - * + * Thumbnail creation for epub files. */ class Epubthumb { /** - * @brief Match for application/epub+zip. + * Match for application/epub+zip. * * @param string $type MimeType * @return boolean */ - function Match($type) { - return(($type === 'application/epub+zip') ? true : false ); + function Match(string $type): bool { + return $type === 'application/epub+zip'; } /** - * @brief + * Create the thumbnail if the Epub has a cover. * * @param array $attach - * @param number $preview_style unused - * @param number $height (optional) default 300 - * @param number $width (optional) default 300 + * @param int $preview_style unused + * @param int $height (optional) default 300 + * @param int $width (optional) default 300 + * + * @SuppressWarnings(PHPMD.UnusedFormalParameter) + * phpcs:disable Generic.CodeAnalysis.UnusedFunctionParameter.FoundBeforeLastUsed */ - function Thumb($attach, $preview_style, $height = 300, $width = 300) { + function Thumb($attach, $preview_style, $height = 300, $width = 300): void { $file = dbunescbin($attach['content']); if (!$file) { return; } - $photo = false; - - $ep = new \EPub($file); - $data = $ep->Cover(); - - if($data['found']) { - $photo = $data['data']; - } + $image = $this->getCoverFromEpub($file); - if($photo) { - $image = imagecreatefromstring($photo); - $dest = imagecreatetruecolor($width, $height); + if ($image) { $srcwidth = imagesx($image); $srcheight = imagesy($image); + $dest = imagecreatetruecolor($width, $height); imagealphablending($dest, false); imagesavealpha($dest, true); + imagecopyresampled($dest, $image, 0, 0, 0, 0, $width, $height, $srcwidth, $srcheight); + + imagejpeg($dest, "{$file}.thumb"); + imagedestroy($image); - imagejpeg($dest, dbunescbin($attach['content']) . '.thumb'); + imagedestroy($dest); } } + + /** + * Fetch the cover from the epub archive, if it's present. + * + * There's a few limitations here: This will only work if the cover + * is a raster image of a supported format. SVG does not work, neither + * will other schemes sometimes used for cover/front page. + * + * @param string $filename The local filename of the epub archive. + * + * @return GdImage|false If a cover is found, it is returned as a + * GdImage object. Otherwise return false. + */ + private function getCoverFromEpub(string $filename): GdImage|false { + $epub = new ZipArchive(); + $rc = $epub->open($filename, ZipArchive::RDONLY); + + if ($rc !== true) { + logger("Error opening file '{$filename}': rc = ${rc}.", LOGGER_DEBUG, LOG_DEBUG); + return false; + } + + $cover = false; + $cover_name = $this->parseEpub($epub); + if ($cover_name !== false) { + $cover = $epub->getFromName($cover_name); + if ($cover === false) { + logger("File '{$cover_name}' not found in EPUB.", LOGGER_DEBUG, LOG_DEBUG); + } + } + + $epub->close(); + + if ($cover !== false && !empty($cover)) { + return imagecreatefromstring($cover); + } else { + return false; + } + } + + /** + * Parse the epub to find the path of the cover image. + * + * @param ZipArchive $epub An opened epub ZipArchive. + * + * @return string|false The path to the cover image or false. + */ + private function parseEpub(ZipArchive $epub): string|false { + $packagePath = $this->getEpubPackagePath($epub); + if ($packagePath !== false) { + $package = $epub->getFromName($packagePath); + if ($package === false || empty($package)) { + logger("Package file '${packagePath}' not found in EPUB", LOGGER_DEBUG, LOG_DEBUG); + return false; + } + + $domdoc = new DOMDocument(); + $domdoc->loadXML($package); + $xpath = new DOMXPath($domdoc); + $xpath->registerNamespace("n", "http://www.idpf.org/2007/opf"); + $nodes = $xpath->query('/n:package/n:manifest/n:item[@properties="cover-image"]'); + + if ($nodes->count() === 0) { + logger('No cover found in EPUB manifest.', LOGGER_DEBUG, LOG_DEBUG); + return false; + } + + $node = $nodes->item(0); + if ($node === null) { + logger('No nodes in non-empty node list?', LOGGER_DEBUG, LOG_DEBUG); + return false; + } + + if (is_a($node, DOMElement::class)) { + // The URL's in the package file is relative to the subdirectory + // within the epub archive where it is located. See + // https://www.w3.org/TR/epub-33/#sec-parsing-urls-metainf + return dirname($packagePath) . '/' . $node->getAttribute('href'); + } + } + + return false; + } + + /** + * Locate the package file within the epub. + * + * The package file in an epub archive contains the manifest + * that again may contain a reference to the cover for the + * epub. + * + * @param ZipArchive $epub An opened epub archive. + * + * @return string|false The full pathname of the package file or false. + */ + private function getEpubPackagePath(ZipArchive $epub): string|false { + // + // The only mandatory known file within the archive is the + // container file, so we fetch it to find the reference to + // the package file. + // + // See: https://www.w3.org/TR/epub-33/#sec-container-metainf + // + $container = $epub->getFromName('META-INF/container.xml'); + + if ($container === false || empty($container)) { + logger('No container in archive, probably not an EPUB.', LOGGER_DEBUG, LOG_DEBUG); + return false; + } + + $domdoc = new DOMDocument(); + $domdoc->loadXML($container); + $nodes = $domdoc->getElementsByTagName('rootfile'); + + if ($nodes->count() == 0) { + logger('EPUB rootfile not found, is this an epub?', LOGGER_DEBUG, LOG_DEBUG); + return false; + } + + $packageNode = $nodes->item(0); + if ($packageNode === null || !is_a($packageNode, DOMElement::class)) { + logger('EPUB rootfile element missing or invalid.', LOGGER_DEBUG, LOG_DEBUG); + return false; + } + + $packagePath = $packageNode->getAttribute('full-path'); + $packageMediaType = $packageNode->getAttribute('media-type'); + + if (empty($packagePath) || $packageMediaType !== 'application/oebps-package+xml') { + logger('EPUB package path missing or incorrect media type.', LOGGER_DEBUG, LOG_DEBUG); + return false; + } + + return $packagePath; + } } |