Merge pull request #1098 from kiwix/united_states_of_books

Declaration of USB (Unified States of Books)

src/contentmanager.cpp

@@ -218,26 +218,40 @@ void ContentManager::onCustomContextMenu(const QPoint &point)
     QAction menuCancelBook(gt("cancel-download"), this);
     QAction menuOpenFolder(gt("open-folder"), this);
 
-    if (const auto download = bookNode->getDownloadState()) {
+    const auto bookState = getBookState(id);
-        if (download->paused) {
+    switch ( bookState ) {
+    case BookState::DOWNLOAD_PAUSED:
         contextMenu.addAction(&menuResumeBook);
-        } else {
-            contextMenu.addAction(&menuPauseBook);
-        }
         contextMenu.addAction(&menuCancelBook);
-    } else {
+        break;
-        try {
+
+    case BookState::DOWNLOADING:
+        contextMenu.addAction(&menuPauseBook);
+        contextMenu.addAction(&menuCancelBook);
+        break;
+
+    case BookState::AVAILABLE_LOCALLY_AND_HEALTHY:
+    case BookState::ERROR_MISSING_ZIM_FILE:
+    case BookState::ERROR_CORRUPTED_ZIM_FILE:
+        {
             const auto book = mp_library->getBookById(id);
             auto bookPath = QString::fromStdString(book.getPath());
+            if ( bookState == BookState::AVAILABLE_LOCALLY_AND_HEALTHY ) {
                 contextMenu.addAction(&menuOpenBook);
+            }
             contextMenu.addAction(&menuDeleteBook);
             contextMenu.addAction(&menuOpenFolder);
             connect(&menuOpenFolder, &QAction::triggered, [=]() {
                 openFileLocation(bookPath, mp_view);
             });
-        } catch (...) {
+            break;
-            contextMenu.addAction(&menuDownloadBook);
         }
+
+    case BookState::AVAILABLE_ONLINE:
+        contextMenu.addAction(&menuDownloadBook);
+        break;
+
+    default: break;
     }
 
     connect(&menuDeleteBook, &QAction::triggered, [=]() {
@@ -390,6 +404,19 @@ QVariant getBookAttribute(const kiwix::Book& b, const QString& a)
     return QVariant();
 }
 
+ContentManager::BookState getStateOfLocalBook(const kiwix::Book& book)
+{
+    if ( !book.isPathValid() ) {
+        return ContentManager::BookState::ERROR_MISSING_ZIM_FILE;
+    }
+
+    // XXX: When a book is detected to be corrupted, information about that
+    // XXX: has to be recorded somewhere so that we can return
+    // XXX: ERROR_CORRUPTED_ZIM_FILE here
+
+    return ContentManager::BookState::AVAILABLE_LOCALLY_AND_HEALTHY;
+}
+
 } // unnamed namespace
 
 ContentManager::BookInfo ContentManager::getBookInfos(QString id, const QStringList &keys)
@@ -420,17 +447,40 @@ ContentManager::BookInfo ContentManager::getBookInfos(QString id, const QStringL
     return values;
 }
 
+ContentManager::BookState ContentManager::getBookState(QString bookId)
+{
+    if ( const auto downloadState = m_downloads.value(bookId) ) {
+        return downloadState->paused
+             ? BookState::DOWNLOAD_PAUSED
+             : BookState::DOWNLOADING;
+             // TODO: a download may be in error state
+    }
+
+    try {
+        const kiwix::Book& b = mp_library->getBookById(bookId);
+        return b.getDownloadId().empty()
+             ? getStateOfLocalBook(b)
+             : BookState::DOWNLOADING;
+    } catch (...) {}
+
+    try {
+        QMutexLocker locker(&remoteLibraryLocker);
+        const kiwix::Book& b = mp_remoteLibrary->getBookById(bookId.toStdString());
+        return !b.getUrl().empty()
+             ? BookState::AVAILABLE_ONLINE
+             : BookState::METADATA_ONLY;
+    } catch (...) {}
+
+    return BookState::INVALID;
+}
+
 void ContentManager::openBookWithIndex(const QModelIndex &index)
 {
-    try {
     auto bookNode = static_cast<Node*>(index.internalPointer());
     const QString bookId = bookNode->getBookId();
-        // throws std::out_of_range if the book isn't available in local library
+    if ( getBookState(bookId) == BookState::AVAILABLE_LOCALLY_AND_HEALTHY ) {
-        const kiwix::Book& book = mp_library->getBookById(bookId);
-        if ( !book.getDownloadId().empty() )
-            return;
         openBook(bookId);
-    } catch (std::out_of_range &e) {}
+    }
 }
 
 void ContentManager::openBook(const QString &id)

src/contentmanager.h

@@ -20,6 +20,43 @@ public: // types
     typedef ContentManagerModel::BookInfo     BookInfo;
     typedef ContentManagerModel::BookInfoList BookInfoList;
 
+    enum class BookState
+    {
+        // Nothing known about a book with that id
+        INVALID,
+
+        // Only (some) metadata is available for the book, however neither a
+        // ZIM-file nor a URL is associated with it.
+        METADATA_ONLY,
+
+        // No ZIM file is associated with the book but a URL is provided.
+        AVAILABLE_ONLINE,
+
+        // The book is being downloaded.
+        DOWNLOADING,
+
+        // The book started downloading, but the download is currently paused.
+        DOWNLOAD_PAUSED,
+
+        // The book started downloading but the download was stopped due to
+        // errors.
+        DOWNLOAD_ERROR,
+
+        // A valid ZIM file path is associated with the book and no evidence
+        // about any issues with that ZIM file has so far been obtained.
+        AVAILABLE_LOCALLY_AND_HEALTHY,
+
+        // A ZIM file path is associated with the book but no such file seems
+        // to exist (may be caused by missing read permissions for the directory
+        // containing the ZIM file).
+        ERROR_MISSING_ZIM_FILE,
+
+        // A ZIM file is associated with the book but it cannot be opened
+        // due to issues with its content.
+        ERROR_CORRUPTED_ZIM_FILE
+    };
+
+
 public: // functions
     explicit ContentManager(Library* library, kiwix::Downloader *downloader, QObject *parent = nullptr);
     virtual ~ContentManager();
@@ -49,6 +86,7 @@ signals:
 public slots:
     QStringList getTranslations(const QStringList &keys);
     BookInfo getBookInfos(QString id, const QStringList &keys);
+    BookState getBookState(QString id);
     void openBook(const QString& id);
     void downloadBook(const QString& id);
     void downloadBook(const QString& id, QModelIndex index);

src/contentmanagerdelegate.cpp

@@ -146,17 +146,39 @@ void showDownloadProgress(QPainter *painter, QRect box, const DownloadState& dow
     createArc(painter, startAngle, spanAngle, rectangle, pen);
 }
 
-void ContentManagerDelegate::paint(QPainter *painter, const QStyleOptionViewItem &option, const QModelIndex &index) const
+void ContentManagerDelegate::paintButton(QPainter *p, const QRect &r, QString t) const
 {
     QStyleOptionButton button;
-    QRect r = option.rect;
+    button.rect = r;
-    int x,y,w,h;
-    x = r.left();
-    y = r.top();
-    w = r.width();
-    h = r.height();
-    button.rect = QRect(x,y,w,h);
     button.state = QStyle::State_Enabled;
+    button.text = t;
+    baseButton->style()->drawControl( QStyle::CE_PushButton, &button, p, baseButton.data());
+}
+
+void ContentManagerDelegate::paintBookState(QPainter *p, QRect r, const QModelIndex &index) const
+{
+    const auto node = static_cast<RowNode*>(index.internalPointer());
+    const auto id = node->getBookId();
+    switch ( KiwixApp::instance()->getContentManager()->getBookState(id) ) {
+    case ContentManager::BookState::AVAILABLE_LOCALLY_AND_HEALTHY:
+        return paintButton(p, r, gt("open"));
+
+    case ContentManager::BookState::AVAILABLE_ONLINE:
+        return paintButton(p, r, gt("download"));
+
+    case ContentManager::BookState::DOWNLOADING:
+    case ContentManager::BookState::DOWNLOAD_PAUSED:
+    case ContentManager::BookState::DOWNLOAD_ERROR:
+        return showDownloadProgress(p, r, *node->getDownloadState());
+
+    default:
+        return;
+    }
+}
+
+void ContentManagerDelegate::paint(QPainter *painter, const QStyleOptionViewItem &option, const QModelIndex &index) const
+{
+    QRect r = option.rect;
     if (index.parent().isValid()) {
         // additional info
         QRect nRect = r;
@@ -165,24 +187,9 @@ void ContentManagerDelegate::paint(QPainter *painter, const QStyleOptionViewItem
         painter->drawText(nRect, Qt::AlignLeft | Qt::AlignVCenter, index.data(Qt::UserRole+1).toString());
         return;
     }
-    auto node = static_cast<RowNode*>(index.internalPointer());
-    try {
-        const auto id = node->getBookId();
-        const auto book = KiwixApp::instance()->getLibrary()->getBookById(id);
-        if ( book.getDownloadId().empty() ) {
-            button.text = gt("open");
-        }
-    } catch (std::out_of_range& e) {
-        button.text = gt("download");
-    }
     QStyleOptionViewItem eOpt = option;
     if (index.column() == 5) {
-        if (const auto downloadState = node->getDownloadState()) {
+        paintBookState(painter, option.rect, index);
-            showDownloadProgress(painter, r, *downloadState);
-        }
-        else {
-            baseButton->style()->drawControl( QStyle::CE_PushButton, &button, painter, baseButton.data());
-        }
         return;
     }
     if (index.column() == 0) {
@@ -192,7 +199,7 @@ void ContentManagerDelegate::paint(QPainter *painter, const QStyleOptionViewItem
         QPixmap pix;
         pix.loadFromData(iconData);
         QIcon icon(pix);
-        icon.paint(painter, QRect(x+10, y+10, 30, 50));
+        icon.paint(painter, QRect(r.left()+10, r.top()+10, 30, 50));
         return;
     }
     if (index.column() == 1) {
@@ -249,23 +256,24 @@ void ContentManagerDelegate::handleLastColumnClicked(const QModelIndex& index, Q
     int x = r.left();
     int w = r.width();
 
-    if (const auto downloadState = node->getDownloadState()) {
+    ContentManager& contentMgr = *KiwixApp::instance()->getContentManager();
-        if (downloadState->paused) {
+    switch ( contentMgr.getBookState(id) ) {
-            if (clickX < (x + w/2)) {
+    case ContentManager::BookState::AVAILABLE_LOCALLY_AND_HEALTHY:
-                KiwixApp::instance()->getContentManager()->cancelBook(id);
+        return contentMgr.openBook(id);
-            } else {
+
-                KiwixApp::instance()->getContentManager()->resumeBook(id, index);
+    case ContentManager::BookState::AVAILABLE_ONLINE:
-            }
+        return contentMgr.downloadBook(id, index);
-        } else {
+
-            KiwixApp::instance()->getContentManager()->pauseBook(id, index);
+    case ContentManager::BookState::DOWNLOADING:
-        }
+        return contentMgr.pauseBook(id, index);
-    } else {
+
-            try {
+    case ContentManager::BookState::DOWNLOAD_PAUSED:
-                const auto book = KiwixApp::instance()->getLibrary()->getBookById(id);
+        return clickX < (x + w/2)
-                KiwixApp::instance()->getContentManager()->openBook(id);
+             ? contentMgr.cancelBook(id)
-            } catch (std::out_of_range& e) {
+             : contentMgr.resumeBook(id, index);
-                KiwixApp::instance()->getContentManager()->downloadBook(id, index);
+
-            }
+    default:
+        return;
     }
 }
 

src/contentmanagerdelegate.h

@@ -15,6 +15,10 @@ public:
     bool editorEvent(QEvent *event, QAbstractItemModel *model, const QStyleOptionViewItem &option, const QModelIndex &index) override;
     QSize sizeHint(const QStyleOptionViewItem &option, const QModelIndex &index) const override;
 
+private: // functions
+    void paintBookState(QPainter *p, QRect r, const QModelIndex &index) const;
+    void paintButton(QPainter *p, const QRect &r, QString t) const;
+
 private:
     QScopedPointer<QPushButton> baseButton;
     QByteArray placeholderIcon;