WIP: network loadingwip/network-loading

10 files changed, 133 insertions, 63 deletions

diff --git a/examples/widgets/pdfviewer/main.cpp b/examples/widgets/pdfviewer/main.cpp
index 51a3f98..271c25f 100644
--- a/examples/widgets/pdfviewer/main.cpp
+++ b/examples/widgets/pdfviewer/main.cpp
@@ -9,7 +9,7 @@ int main(int argc, char *argv[])
     QStringList args = a.arguments();
     w.show();
     if (args.length() > 1)
-        w.open(QUrl::fromLocalFile(args[1]));
+        w.open(QUrl::fromUserInput(args[1]));
 
     return a.exec();
 }
diff --git a/examples/widgets/pdfviewer/mainwindow.cpp b/examples/widgets/pdfviewer/mainwindow.cpp
index f3fa000..0836012 100644
--- a/examples/widgets/pdfviewer/mainwindow.cpp
+++ b/examples/widgets/pdfviewer/mainwindow.cpp
@@ -45,12 +45,7 @@ MainWindow::~MainWindow()
 
 void MainWindow::open(const QUrl &docLocation)
 {
-    if (docLocation.isLocalFile())
-        m_pageWidget->openDocument(docLocation);
-    else {
-        qCDebug(lcExample) << docLocation << "is not a valid local file";
-        QMessageBox::critical(this, tr("Failed to open"), tr("%1 is not a valid local file").arg(docLocation.toString()));
-    }
+    m_pageWidget->openDocument(docLocation);
     qCDebug(lcExample) << docLocation;
     ui->scrollArea->ensureVisible(0, 0, 0, 0);
 }
diff --git a/examples/widgets/pdfviewer/pagerenderer.cpp b/examples/widgets/pdfviewer/pagerenderer.cpp
index fca4a0f..5270728 100644
--- a/examples/widgets/pdfviewer/pagerenderer.cpp
+++ b/examples/widgets/pdfviewer/pagerenderer.cpp
@@ -4,69 +4,104 @@
 #include <QLoggingCategory>
 #include <QElapsedTimer>
 #include <QUrl>
+#include <QNetworkRequest>
+#include <QNetworkReply>
 
 Q_DECLARE_LOGGING_CATEGORY(lcExample)
 
 PageRenderer::PageRenderer()
-    : QThread(Q_NULLPTR)
-    , m_doc(new QPdfDocument(this))
-    , m_page(0)
-    , m_zoom(1.)
+    : m_networkAccessManager(new QNetworkAccessManager(this))
     , m_minRenderTime(1000000000.)
     , m_maxRenderTime(0.)
     , m_totalRenderTime(0.)
     , m_totalPagesRendered(0)
 {
+    qRegisterMetaType<QVector<QSizeF> >();
+
+    m_workerThread.start();
+    moveToThread(&m_workerThread);
+
+    connect(&m_doc, SIGNAL(documentLoadStarted()), this, SLOT(reportPageSizes()));
+    connect(&m_doc, SIGNAL(pageAvailable(int)), this, SLOT(renderPageIfRequested(int)));
 }
 
 PageRenderer::~PageRenderer()
 {
+    m_workerThread.exit();
 }
 
-QVector<QSizeF> PageRenderer::openDocument(const QUrl &location)
+void PageRenderer::openDocument(const QUrl &location)
 {
-    if (location.isLocalFile())
-        m_doc.load(location.toLocalFile());
-    else {
-        qCWarning(lcExample, "non-local file loading is not implemented");
-        return QVector<QSizeF>();
-    }
-    // TODO maybe do in run() if it takes too long
-    QVector<QSizeF> pageSizes;
-    for (int page = 0; page < m_doc.pageCount(); ++page)
-        pageSizes.append(m_doc.pageSize(page));
-    return pageSizes;
+    QMetaObject::invokeMethod(this, "loadDocumentImpl", Qt::QueuedConnection, Q_ARG(QUrl, location));
+}
+
+void PageRenderer::requestPage(int page, qreal zoom)
+{
+    QMetaObject::invokeMethod(this, "requestPageImpl", Qt::QueuedConnection, Q_ARG(int, page), Q_ARG(qreal, zoom));
+}
+
+void PageRenderer::reportPageSizes()
+{
+    QVector<QSizeF> sizes;
+    for (int i = 0, count = m_doc.pageCount(); i < count; ++i)
+        sizes << m_doc.pageSize(i);
+    emit pageSizesAvailable(sizes);
+    if (!m_renderRequests.isEmpty())
+        QMetaObject::invokeMethod(this, "renderPages", Qt::QueuedConnection);
 }
 
-void PageRenderer::requestPage(int page, qreal zoom, Priority priority)
+void PageRenderer::loadDocumentImpl(const QUrl &url)
 {
-    // TODO maybe queue up the requests
-    m_page = page;
-    m_zoom = zoom;
-    start(priority);
+    m_renderRequests.clear();
+    QNetworkReply *reply = m_networkAccessManager->get(QNetworkRequest(url));
+    connect(reply, SIGNAL(error(QNetworkReply::NetworkError)), this, SLOT(handleNetworkRequestError()));
+    m_doc.load(reply);
+    connect(&m_doc, SIGNAL(documentLoadFinished()), reply, SLOT(deleteLater()));
 }
 
-void PageRenderer::run()
+void PageRenderer::requestPageImpl(int page, qreal zoom)
 {
-    renderPage(m_page, m_zoom);
+    RenderRequest newRequest;
+    newRequest.page = page;
+    newRequest.zoom = zoom;
+    m_renderRequests << newRequest;
+    if (!m_doc.isLoading())
+        QMetaObject::invokeMethod(this, "renderPages", Qt::QueuedConnection);
 }
 
-void PageRenderer::renderPage(int page, qreal zoom)
+void PageRenderer::renderPages()
 {
-    QSizeF size = m_doc.pageSize(page) * m_zoom;
-    QElapsedTimer timer; timer.start();
-    const QImage &img = m_doc.render(page, size);
-    qreal secs = timer.nsecsElapsed() / 1000000000.0;
-    if (secs < m_minRenderTime)
-        m_minRenderTime = secs;
-    if (secs > m_maxRenderTime)
-        m_maxRenderTime = secs;
-    m_totalRenderTime += secs;
-    ++m_totalPagesRendered;
-    emit pageReady(page, zoom, img);
+    for (int i = 0; i < m_renderRequests.count(); ++i) {
+        if (!m_doc.canRender(m_renderRequests.at(i).page))
+            continue;
+        RenderRequest request = m_renderRequests.takeAt(i);
 
-    qCDebug(lcExample) << "page" << page << "zoom" << m_zoom << "size" << size << "in" << secs <<
-                          "secs; min" << m_minRenderTime <<
-                          "avg" << m_totalRenderTime / m_totalPagesRendered <<
-                          "max" << m_maxRenderTime;
+        QSizeF size = m_doc.pageSize(request.page) * request.zoom;
+        QElapsedTimer timer; timer.start();
+        QImage img = m_doc.render(request.page, size);
+        qreal secs = timer.nsecsElapsed() / 1000000000.0;
+        if (secs < m_minRenderTime)
+            m_minRenderTime = secs;
+        if (secs > m_maxRenderTime)
+            m_maxRenderTime = secs;
+        m_totalRenderTime += secs;
+        ++m_totalPagesRendered;
+        emit pageReady(request.page, request.zoom, img);
+
+        qCDebug(lcExample) << "page" << request.page << "zoom" << request.zoom << "size" << size << "in" << secs <<
+                              "secs; min" << m_minRenderTime <<
+                              "avg" << m_totalRenderTime / m_totalPagesRendered <<
+                              "max" << m_maxRenderTime;
+        break;
+    }
+}
+
+void PageRenderer::renderPageIfRequested(int page)
+{
+    renderPages();
+}
+
+void PageRenderer::handleNetworkRequestError()
+{
+    qDebug() << static_cast<QNetworkReply*>(sender())->errorString();
 }
diff --git a/examples/widgets/pdfviewer/pagerenderer.h b/examples/widgets/pdfviewer/pagerenderer.h
index 35c8939..a35bc74 100644
--- a/examples/widgets/pdfviewer/pagerenderer.h
+++ b/examples/widgets/pdfviewer/pagerenderer.h
@@ -7,10 +7,11 @@
 #include <QRunnable>
 #include <QThread>
 #include <QPdfDocument>
+#include <QNetworkAccessManager>
 
 class QPdfDocument;
 
-class PageRenderer : public QThread
+class PageRenderer : public QObject
 {
     Q_OBJECT
 public:
@@ -18,24 +19,31 @@ public:
     ~PageRenderer();
 
 public slots:
-    QVector<QSizeF> openDocument(const QUrl &location);
-    void requestPage(int page, qreal zoom, Priority priority = QThread::NormalPriority);
+    void openDocument(const QUrl &location);
+    void requestPage(int page, qreal zoom);
 
 signals:
+    void pageSizesAvailable(const QVector<QSizeF> &sizes);
     void pageReady(int page, qreal zoom, QImage image);
 
-protected:
-    void run() Q_DECL_OVERRIDE;
-
-private:
-    void renderPage(int page, qreal zoom);
+private slots:
+    void reportPageSizes();
+    void loadDocumentImpl(const QUrl &url);
+    void requestPageImpl(int page, qreal zoom);
+    void renderPages();
+    void renderPageIfRequested(int page);
+    void handleNetworkRequestError();
 
 private:
+    QThread m_workerThread;
     QPdfDocument m_doc;
 
-    // current request only
-    int m_page;
-    qreal m_zoom;
+    struct RenderRequest {
+        int page;
+        qreal zoom;
+    };
+    QVector<RenderRequest> m_renderRequests;
+    QNetworkAccessManager *m_networkAccessManager;
 
     // performance statistics
     qreal m_minRenderTime;
diff --git a/examples/widgets/pdfviewer/pdfviewer.pro b/examples/widgets/pdfviewer/pdfviewer.pro
index e8269c4..9107983 100644
--- a/examples/widgets/pdfviewer/pdfviewer.pro
+++ b/examples/widgets/pdfviewer/pdfviewer.pro
@@ -1,4 +1,4 @@
-QT       += core gui widgets pdf
+QT       += core gui widgets pdf network
 TARGET = pdfviewer
 TEMPLATE = app
 
diff --git a/examples/widgets/pdfviewer/sequentialpagewidget.cpp b/examples/widgets/pdfviewer/sequentialpagewidget.cpp
index c85f784..4073302 100644
--- a/examples/widgets/pdfviewer/sequentialpagewidget.cpp
+++ b/examples/widgets/pdfviewer/sequentialpagewidget.cpp
@@ -21,6 +21,7 @@ SequentialPageWidget::SequentialPageWidget(QWidget *parent)
     , m_zoom(1.)
     , m_screenResolution(QGuiApplication::primaryScreen()->logicalDotsPerInch() / 72.0)
 {
+    connect(m_pageRenderer, SIGNAL(pageSizesAvailable(QVector<QSizeF>)), this, SLOT(preparePages(QVector<QSizeF>)));
     connect(m_pageRenderer, SIGNAL(pageReady(int, qreal, QImage)), this, SLOT(pageLoaded(int, qreal, QImage)), Qt::QueuedConnection);
 }
 
@@ -31,9 +32,7 @@ SequentialPageWidget::~SequentialPageWidget()
 
 void SequentialPageWidget::openDocument(const QUrl &url)
 {
-    m_pageSizes = m_pageRenderer->openDocument(url);
-    m_topPageShowing = 0;
-    invalidate();
+    m_pageRenderer->openDocument(url);
 }
 
 void SequentialPageWidget::setZoom(qreal factor)
@@ -66,6 +65,13 @@ void SequentialPageWidget::invalidate()
     update();
 }
 
+void SequentialPageWidget::preparePages(const QVector<QSizeF> &pageSizes)
+{
+    m_pageSizes = pageSizes;
+    m_topPageShowing = 0;
+    invalidate();
+}
+
 void SequentialPageWidget::pageLoaded(int page, qreal zoom, QImage image)
 {
     Q_UNUSED(zoom)
diff --git a/examples/widgets/pdfviewer/sequentialpagewidget.h b/examples/widgets/pdfviewer/sequentialpagewidget.h
index 2a3025d..edf7d53 100644
--- a/examples/widgets/pdfviewer/sequentialpagewidget.h
+++ b/examples/widgets/pdfviewer/sequentialpagewidget.h
@@ -29,6 +29,7 @@ signals:
     void zoomChanged(qreal factor);
 
 private slots:
+    void preparePages(const QVector<QSizeF> &pageSizes);
     void pageLoaded(int page, qreal zoom, QImage image);
 
 private:
diff --git a/src/pdf/qpdfdocument.cpp b/src/pdf/qpdfdocument.cpp
index b48bbda..4d7990d 100644
--- a/src/pdf/qpdfdocument.cpp
+++ b/src/pdf/qpdfdocument.cpp
@@ -57,6 +57,7 @@ void QPdfDocumentPrivate::clear()
     avail = 0;
 
     loadComplete = false;
+    reportedAvailablePages.clear();
 
     asyncBuffer.close();
     asyncBuffer.setData(QByteArray());
@@ -169,8 +170,11 @@ void QPdfDocumentPrivate::tryLoadDocument()
     updateLastError();
     if (lastError == QPdfDocument::IncorrectPasswordError)
         emit q->passwordRequired();
-    else if (doc)
+    else if (doc) {
         emit q->documentLoadStarted();
+        reportedAvailablePages.resize(FPDF_GetPageCount(doc));
+        reportedAvailablePages.fill(false);
+    }
 }
 
 void QPdfDocumentPrivate::checkComplete()
@@ -187,8 +191,14 @@ void QPdfDocumentPrivate::checkComplete()
 
     loadComplete = true;
     for (int i = 0, count = FPDF_GetPageCount(doc); i < count; ++i)
-        if (!FPDFAvail_IsPageAvail(avail, i, this))
+        if (FPDFAvail_IsPageAvail(avail, i, this)) {
+            if (!reportedAvailablePages.at(i)) {
+                reportedAvailablePages[i] = true;
+                emit q->pageAvailable(i);
+            }
+        } else {
             loadComplete = false;
+        }
     if (loadComplete)
         emit q->documentLoadFinished();
 }
@@ -285,6 +295,14 @@ QSizeF QPdfDocument::pageSize(int page) const
     return result;
 }
 
+bool QPdfDocument::canRender(int page) const
+{
+    QMutexLocker lock(pdfMutex());
+    if (!d->doc)
+        return false;
+    return d->reportedAvailablePages.at(page);
+}
+
 QImage QPdfDocument::render(int page, const QSizeF &pageSize)
 {
     if (!d->doc)
@@ -292,6 +310,9 @@ QImage QPdfDocument::render(int page, const QSizeF &pageSize)
 
     QMutexLocker lock(pdfMutex());
 
+    if (!FPDFAvail_IsPageAvail(d->avail, page, d.data()))
+        return QImage();
+
     FPDF_PAGE pdfPage = FPDF_LoadPage(d->doc, page);
     if (!pdfPage)
         return QImage();
diff --git a/src/pdf/qpdfdocument.h b/src/pdf/qpdfdocument.h
index 6459f39..c846333 100644
--- a/src/pdf/qpdfdocument.h
+++ b/src/pdf/qpdfdocument.h
@@ -44,11 +44,13 @@ public:
 
     QSizeF pageSize(int page) const;
 
+    bool canRender(int page) const;
     QImage render(int page, const QSizeF &pageSize);
 
 Q_SIGNALS:
     void passwordRequired();
     void documentLoadStarted();
+    void pageAvailable(int page);
     void documentLoadFinished();
     void pageCountChanged();
 
diff --git a/src/pdf/qpdfdocument_p.h b/src/pdf/qpdfdocument_p.h
index 7850c65..2e19fb0 100644
--- a/src/pdf/qpdfdocument_p.h
+++ b/src/pdf/qpdfdocument_p.h
@@ -9,6 +9,7 @@
 #include <qbuffer.h>
 #include <qnetworkreply.h>
 #include <qpointer.h>
+#include <qbitarray.h>
 
 QT_BEGIN_NAMESPACE
 
@@ -23,6 +24,7 @@ public:
     FPDF_AVAIL avail;
     FPDF_DOCUMENT doc;
     bool loadComplete;
+    QBitArray reportedAvailablePages;
 
     QPointer<QIODevice> device;
     QScopedPointer<QIODevice> ownDevice;