Moved error detection to DownloadManager

src/contentmanager.cpp

@@ -8,7 +8,6 @@
 #include <QUrlQuery>
 #include <QUrl>
 #include <QDir>
-#include <QStorageInfo>
 #include <QMessageBox>
 #include "contentmanagermodel.h"
 #include <zim/error.h>
@@ -32,35 +31,6 @@ SettingsManager* getSettingsManager()
     return KiwixApp::instance()->getSettingsManager();
 }
 
-void throwDownloadUnavailableError()
-{
-    throw KiwixAppError(gt("download-unavailable"),
-                        gt("download-unavailable-text"));
-}
-
-void checkThatBookCanBeSaved(const kiwix::Book& book, QString targetDir)
-{
-    const QFileInfo targetDirInfo(targetDir);
-    if ( !targetDirInfo.isDir() ) {
-        throw KiwixAppError(gt("download-storage-error"),
-                            gt("download-dir-missing"));
-    }
-
-    // XXX: This may lie under Windows
-    // XXX: (see https://doc.qt.io/qt-5/qfile.html#platform-specific-issues)
-    if ( !targetDirInfo.isWritable() ) {
-        throw KiwixAppError(gt("download-storage-error"),
-                            gt("download-dir-not-writable"));
-    }
-
-    QStorageInfo storage(targetDir);
-    auto bytesAvailable = storage.bytesAvailable();
-    if (bytesAvailable == -1 || book.getSize() > (unsigned long long) bytesAvailable) {
-        throw KiwixAppError(gt("download-storage-error"),
-                            gt("download-storage-error-text"));
-    }
-}
-
 // Opens the directory containing the input file path.
 // parent is the widget serving as the parent for the error dialog in case of
 // failure.
@@ -567,14 +537,7 @@ QString ContentManager::getRemoteLibraryUrl() const
 
 void ContentManager::downloadBook(kiwix::Book book, const QString& downloadPath)
 {
-    checkThatBookCanBeSaved(book, downloadPath);
-
-    std::string downloadId;
-    try {
-        downloadId = DownloadManager::startDownload(book, downloadPath.toStdString());
-    } catch (std::exception& e) {
-        throwDownloadUnavailableError();
-    }
+    const std::string downloadId = DownloadManager::startDownload(book, downloadPath);
 
     book.setDownloadId(downloadId);
     mp_library->addBookBeingDownloaded(book, downloadPath);

src/downloadmanagement.cpp

@@ -1,5 +1,9 @@
 #include "downloadmanagement.h"
 
+#include "kiwixapp.h"
+#include "kiwixconfirmbox.h"
+
+#include <QStorageInfo>
 #include <QThread>
 
 ////////////////////////////////////////////////////////////////////////////////
@@ -135,20 +139,63 @@ DownloadInfo DownloadManager::getDownloadInfo(QString bookId) const
     };
 }
 
-std::string DownloadManager::startDownload(const kiwix::Book& book, const std::string& downloadDirPath)
+namespace
+{
+
+void throwDownloadUnavailableError()
+{
+    throw KiwixAppError(gt("download-unavailable"),
+                        gt("download-unavailable-text"));
+}
+
+void checkThatBookCanBeSaved(const kiwix::Book& book, QString targetDir)
+{
+    const QFileInfo targetDirInfo(targetDir);
+    if ( !targetDirInfo.isDir() ) {
+        throw KiwixAppError(gt("download-storage-error"),
+                            gt("download-dir-missing"));
+    }
+
+    // XXX: This may lie under Windows
+    // XXX: (see https://doc.qt.io/qt-5/qfile.html#platform-specific-issues)
+    if ( !targetDirInfo.isWritable() ) {
+        throw KiwixAppError(gt("download-storage-error"),
+                            gt("download-dir-not-writable"));
+    }
+
+    QStorageInfo storage(targetDir);
+    auto bytesAvailable = storage.bytesAvailable();
+    if (bytesAvailable == -1 || book.getSize() > (unsigned long long) bytesAvailable) {
+        throw KiwixAppError(gt("download-storage-error"),
+                            gt("download-storage-error-text"));
+    }
+}
+
+} // unnamed namespace
+
+
+std::string DownloadManager::startDownload(const kiwix::Book& book, const QString& downloadDirPath)
 {
     if ( ! DownloadManager::downloadingFunctionalityAvailable() )
-        throw std::runtime_error("Downloading functionality is not available");
+        throwDownloadUnavailableError();
+
+    checkThatBookCanBeSaved(book, downloadDirPath);
 
     typedef std::vector<std::pair<std::string, std::string>> DownloadOptions;
 
     const std::string& url = book.getUrl();
     const QString bookId = QString::fromStdString(book.getId());
-    const DownloadOptions downloadOptions{{"dir", downloadDirPath}};
+    const DownloadOptions downloadOptions{{"dir", downloadDirPath.toStdString()}};
 
-    const auto d = mp_downloader->startDownload(url, downloadOptions);
+    std::string downloadId;
+    try {
+        const auto d = mp_downloader->startDownload(url, downloadOptions);
+        downloadId = d->getDid();
+    } catch (std::exception& e) {
+        throwDownloadUnavailableError();
+    }
     m_downloads.set(bookId, std::make_shared<DownloadState>());
-    return d->getDid();
+    return downloadId;
 }
 
 void DownloadManager::pauseDownload(const QString& bookId)

src/downloadmanagement.h

@@ -81,7 +81,7 @@ public: // functions
     void updateDownloads();
 
     // returns the download id
-    std::string startDownload(const kiwix::Book& book, const std::string& downloadDirPath);
+    std::string startDownload(const kiwix::Book& book, const QString& downloadDirPath);
     void pauseDownload(const QString& bookId);
     void resumeDownload(const QString& bookId);
     bool cancelDownload(const QString& bookId);