Differential D18738 Diff 51037 thumbnail/ebookcreator.cpp

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thumbnail/ebookcreator.cpp

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1​/*
2​ * Copyright (c) 2019 Kai Uwe Broulik <kde@broulik.de>
3​ *
4​ * This library is free software; you can redistribute it and/or
5​ * modify it under the terms of the GNU Lesser General Public
6​ * License as published by the Free Software Foundation; either
7​ * version 2.1 of the License, or (at your option) version 3, or any
8​ * later version accepted by the membership of KDE e.V. (or its
9​ * successor approved by the membership of KDE e.V.), which shall
10​ * act as a proxy defined in Section 6 of version 3 of the license.
11​ *
12​ * This library is distributed in the hope that it will be useful,
13​ * but WITHOUT ANY WARRANTY; without even the implied warranty of
14​ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15​ * Lesser General Public License for more details.
16​ *
17​ * You should have received a copy of the GNU Lesser General Public
18​ * License along with this library. If not, see <http://www.gnu.org/licenses/>.
19​ */
20​
21​#include "ebookcreator.h"
22​
23​#include <QFile>
24​#include <QImage>
25​#include <QMimeDatabase>
26​#include <QXmlStreamReader>
27​
28​#include <KZip>
29​
30​extern "C"
31​{
32​ Q_DECL_EXPORT ThumbCreator *new_creator()
33​ {
34​ return new EbookCreator;
35​ }
36​}
37​
38​EbookCreator::EbookCreator() = default;
39​
40​EbookCreator::~EbookCreator() = default;
41​
42​bool EbookCreator::create(const QString &path, int width, int height, QImage &image)
43​{
44​ Q_UNUSED(width);
45​ Q_UNUSED(height);
46​
47​ QMimeType mimeType = QMimeDatabase().mimeTypeForFile(path);
48​
49​ if (mimeType.name() == QLatin1String("application/epub+zip")) {
50​ return createEpub(path, image);
51​
52​ } else if (mimeType.name() == QLatin1String("application/x-fictionbook+xml")) {
53​ QFile file(path);
54​ if (!file.open(QIODevice::ReadOnly | QIODevice::Text)) {
55​ return false;
56​ }
57​
58​ return createFb2(&file, image);
59​
60​ } else if (mimeType.name() == QLatin1String("application/x-zip-compressed-fb2")) {
61​ KZip zip(path);
62​ if (!zip.open(QIODevice::ReadOnly)) {
63​ return false;
64​ }
65​
66​ QScopedPointer<QIODevice> zipDevice;
67​
68​ const auto entries = zip.directory()->entries();
69​ for (const QString &entryPath : entries) {
70​ if (entries.count() > 1 && !entryPath.endsWith(QLatin1String(".fb2"))) { // can this done a bit more cleverly?
71​ continue;
72​ }
73​
74​ const auto *entry = zip.directory()->entry(entryPath);
75​ if (!entry || !entry->isFile()) {
76​ return false;
77​ }
78​
79​ zipDevice.reset(static_cast<const KZipFileEntry *>(entry)->createDevice());
80​ }
81​
82​ return createFb2(zipDevice.data(), image);
83​ }
84​
85​ return false;
86​}
87​
88​bool EbookCreator::createEpub(const QString &path, QImage &image)
89​{
90​ KZip zip(path);
91​ if (!zip.open(QIODevice::ReadOnly)) {
92​ return false;
93​ }
94​
95​ QScopedPointer<QIODevice> zipDevice;
96​ QString opfPath;
97​ QString coverId;
98​ QString coverHref;
99​
100​ // First figure out where the OPF file with metadata is
101​ const auto *entry = zip.directory()->entry(QStringLiteral("META-INF/container.xml"));
102​
103​ if (!entry || !entry->isFile()) {
104​ return false;
105​ }
106​
107​ const auto *zipEntry = static_cast<const KZipFileEntry *>(entry);
108​
109​ zipDevice.reset(zipEntry->createDevice());
110​
111​ QXmlStreamReader xml(zipDevice.data());
112​ while (!xml.atEnd() && !xml.hasError()) {
113​ xml.readNext();
114​
115​ if (xml.isStartElement() && xml.name() == QLatin1String("rootfile")) {
116​ opfPath = xml.attributes().value(QStringLiteral("full-path")).toString();
117​ }
118​ }
119​
120​ if (opfPath.isEmpty()) {
121​ return false;
122​ }
123​
124​ // Now read the OPF file and look for a <meta name="cover" content="...">
125​ entry = zip.directory()->entry(opfPath);
126​ if (!entry || !entry->isFile()) {
127​ return false;
128​ }
129​
130​ zipEntry = static_cast<const KZipFileEntry *>(entry);
131​
132​ zipDevice.reset(zipEntry->createDevice());
133​
134​ xml.setDevice(zipDevice.data());
135​
136​ bool inMetadata = false;
137​
138​ while (!xml.atEnd() && !xml.hasError()) {
139​ xml.readNext();
140​
141​ if (xml.name() == QLatin1String("metadata")) {
142​ if (xml.isStartElement()) {
143​ inMetadata = true;
144​ } else if (xml.isEndElement()) {
145​ break;
146​ }
147​ }
148​
149​ if (!inMetadata) {
150​ continue;
151​ }
152​
153​ if (xml.isStartElement() && xml.name() == QLatin1String("meta")) {
154​ const auto attributes = xml.attributes();
155​ if (attributes.value(QStringLiteral("name")) == QLatin1String("cover")) {
156​ coverId = attributes.value(QStringLiteral("content")).toString();
157​ break;
158​ }
159​ }
160​ }
161​
162​ if (coverId.isEmpty()) {
163​ // Maybe we're lucky and the archive contains an iTunesArtwork file from iBooks
164​ entry = zip.directory()->entry(QStringLiteral("iTunesArtwork"));
165​ if (entry && entry->isFile()) {
166​ return image.loadFromData(static_cast<const KZipFileEntry *>(entry)->data());
167​ }
168​
169​ // Maybe there's a file called "cover" somewhere
170​ const QStringList entries = getEntryList(zip.directory(), QString());
171​
172​ for (const QString &name : entries) {
173​ if (!name.contains(QLatin1String("cover"), Qt::CaseInsensitive)) {
174​ continue;
175​ }
176​
177​ entry = zip.directory()->entry(name);
178​ if (!entry || !entry->isFile()) {
179​ continue;
180​ }
181​
182​ if (image.loadFromData(static_cast<const KZipFileEntry *>(entry)->data())) {
183​ return true;
184​ }
185​ }
186​ }
187​
188​ // Read OPF file again from beginning and look for <item id="our id from above" href="...">
189​ zipDevice->seek(0);
190​ xml.setDevice(zipDevice.data());
191​
192​ bool inManifest = false;
193​
194​ while (!xml.atEnd() && !xml.hasError()) {
195​ xml.readNext();
196​
197​ if (xml.name() == QLatin1String("manifest")) {
198​ if (xml.isStartElement()) {
199​ inManifest = true;
200​ } else if (xml.isEndElement()) {
201​ break;
202​ }
203​ }
204​
205​ if (!inManifest) {
206​ continue;
207​ }
208​
209​ if (xml.isStartElement() && xml.name() == QLatin1String("item")) {
210​ const auto attributes = xml.attributes();
211​ if (attributes.value(QStringLiteral("id")).compare(coverId, Qt::CaseInsensitive) == 0) {
212​ coverHref = attributes.value(QStringLiteral("href")).toString();
213​ break;
214​ }
215​ }
216​ }
217​
218​ if (coverHref.isEmpty()) {
219​ return false;
220​ }
221​
222​ // Make coverHref relative to OPF location
223​ const int lastOpfSlash = opfPath.lastIndexOf(QLatin1Char('/'));
224​ if (lastOpfSlash > -1) {
225​ QString basePath = opfPath.left(lastOpfSlash + 1);
226​ coverHref.prepend(basePath);
227​ }
228​
229​ // Finally, just load the cover image file
230​ entry = zip.directory()->entry(coverHref);
231​ if (!entry || !entry->isFile()) {
232​ return false;
233​ }
234​
235​ return image.loadFromData(static_cast<const KZipFileEntry *>(entry)->data());
236​}
237​
238​bool EbookCreator::createFb2(QIODevice *device, QImage &image)
239​{
240​ QString coverId;
241​
242​ QXmlStreamReader xml(device);
243​
244​ bool inFictionBook = false;
245​ bool inDescription = false;
246​ bool inTitleInfo = false;
247​ bool inCoverPage = false;
248​
249​ while (!xml.atEnd() && !xml.hasError()) {
250​ xml.readNext();
251​
252​ if (xml.name() == QLatin1String("FictionBook")) {
253​ if (xml.isStartElement()) {
254​ inFictionBook = true;
255​ } else if (xml.isEndElement()) {
256​ break;
257​ }
258​ } else if (xml.name() == QLatin1String("description")) {
259​ if (xml.isStartElement()) {
260​ inDescription = true;
261​ } else if (xml.isEndElement()) {
262​ inDescription = false;
263​ }
264​ } else if (xml.name() == QLatin1String("title-info")) {
265​ if (xml.isStartElement()) {
266​ inTitleInfo = true;
267​ } else if (xml.isEndElement()) {
268​ inTitleInfo = false;
269​ }
270​ } else if (xml.name() == QLatin1String("coverpage")) {
271​ if (xml.isStartElement()) {
272​ inCoverPage = true;
273​ } else if (xml.isEndElement()) {
274​ inCoverPage = false;
275​ }
276​ }
277​
278​ if (!inFictionBook) {
279​ continue;
280​ }
281​
282​ if (inDescription) {
283​ if (inTitleInfo && inCoverPage) {
284​ if (xml.isStartElement() && xml.name() == QLatin1String("image")) {
285​ const auto attributes = xml.attributes();
286​
287​ // value() wants a namespace but we don't care, so iterate until we find any "href"
288​ for (const auto &attribute : attributes) {
289​ if (attribute.name() == QLatin1String("href")) {
290​ coverId = attribute.value().toString();
291​ if (coverId.startsWith(QLatin1Char('#'))) {
292​ coverId = coverId.mid(1);
293​ }
294​ }
295​ }
296​ }
297​ }
298​ } else {
299​ if (!coverId.isEmpty() && xml.isStartElement() && xml.name() == QLatin1String("binary")) {
300​ if (xml.attributes().value(QStringLiteral("id")) == coverId) {
301​ return image.loadFromData(QByteArray::fromBase64(xml.readElementText().toLatin1()));
302​ }
303​ }
304​ }
305​ }
306​
307​ return false;
308​}
309​
310​QStringList EbookCreator::getEntryList(const KArchiveDirectory *dir, const QString &path)
311​{
312​ QStringList list;
313​
314​ const QStringList entries = dir->entries();
315​ for (const QString &name : entries) {
316​ const KArchiveEntry *entry = dir->entry(name);
317​
318​ QString fullPath = name;
319​
320​ if (!path.isEmpty()) {
321​ fullPath.prepend(QLatin1Char('/'));
322​ fullPath.prepend(path);
323​ }
324​
325​ if (entry->isFile()) {
326​ list << fullPath;
327​ } else {
328​ list << getEntryList(static_cast<const KArchiveDirectory *>(entry), fullPath);
329​ }
330​ }
331​
332​ return list;
333​}