fix: prevent images overriding content when changing pages

Signed-off-by: flow <flowlnlnln@gmail.com>

launcher/ui/pages/modplatform/ModPage.cpp

@@ -350,4 +350,5 @@ void ModPage::updateUi()
 
     HoeDown h;
     ui->packDescription->setHtml(text + (current.extraData.body.isEmpty() ? current.description : h.process(current.extraData.body.toUtf8())));
+    ui->packDescription->flush();
 }

launcher/ui/pages/modplatform/modrinth/ModrinthPage.cpp

@@ -284,6 +284,7 @@ void ModrinthPage::updateUI()
     text += h.process(current.extra.body.toUtf8());
 
     ui->packDescription->setHtml(text + current.description);
+    ui->packDescription->flush();
 }
 
 void ModrinthPage::suggestCurrent()

launcher/ui/widgets/ProjectDescriptionPage.cpp

@@ -15,3 +15,9 @@ void ProjectDescriptionPage::setMetaEntry(QString entry)
     if (m_image_text_object)
         m_image_text_object->setMetaEntry(entry);
 }
+
+void ProjectDescriptionPage::flush()
+{
+    if (m_image_text_object)
+        m_image_text_object->flush();
+}

launcher/ui/widgets/ProjectDescriptionPage.h

@@ -19,6 +19,14 @@ class ProjectDescriptionPage final : public QTextBrowser {
 
     void setMetaEntry(QString entry);
 
+   public slots:
+    /** Flushes the current processing happening in the page.
+     *
+     *  Should be called when changing the page's content entirely, to
+     *  prevent old tasks from changing the new content.
+     */
+    void flush();
+
    private:
     shared_qobject_ptr<VariableSizedImageObject> m_image_text_object;
 };

launcher/ui/widgets/VariableSizedImageObject.cpp

@@ -66,6 +66,11 @@ void VariableSizedImageObject::drawObject(QPainter* painter,
     painter->drawImage(rect, image);
 }
 
+void VariableSizedImageObject::flush()
+{
+    m_fetching_images.clear();
+}
+
 void VariableSizedImageObject::parseImage(QTextDocument* doc, QImage image, int posInDocument)
 {
     QTextCursor cursor(doc);
@@ -85,7 +90,7 @@ void VariableSizedImageObject::parseImage(QTextDocument* doc, QImage image, int
 
 void VariableSizedImageObject::loadImage(QTextDocument* doc, const QUrl& source, int posInDocument)
 {
-    m_fetching_images.append(source);
+    m_fetching_images.insert(source);
 
     MetaEntryPtr entry = APPLICATION->metacache()->resolveEntry(
         m_meta_entry,
@@ -99,6 +104,10 @@ void VariableSizedImageObject::loadImage(QTextDocument* doc, const QUrl& source,
     connect(job, &NetJob::succeeded, [this, doc, full_entry_path, source_url, posInDocument] {
         qDebug() << "Loaded resource at" << full_entry_path;
 
+        // If we flushed, don't proceed.
+        if (!m_fetching_images.contains(source_url))
+            return;
+
         QImage image(full_entry_path);
         doc->addResource(QTextDocument::ImageResource, source_url, image);
 
@@ -110,7 +119,7 @@ void VariableSizedImageObject::loadImage(QTextDocument* doc, const QUrl& source,
         doc->adjustSize();
         doc->setPageSize(size);
 
-        m_fetching_images.removeOne(source_url);
+        m_fetching_images.remove(source_url);
     });
     connect(job, &NetJob::finished, job, &NetJob::deleteLater);
 

launcher/ui/widgets/VariableSizedImageObject.h

@@ -28,7 +28,7 @@
  *  Why? Because we want to re-scale images dynamically based on the document's size, in order to
  *  not have images being weirdly cropped out in different resolutions.
  */
-class VariableSizedImageObject : public QObject, public QTextObjectInterface {
+class VariableSizedImageObject final : public QObject, public QTextObjectInterface {
     Q_OBJECT
     Q_INTERFACES(QTextObjectInterface)
 
@@ -38,7 +38,15 @@ class VariableSizedImageObject : public QObject, public QTextObjectInterface {
 
     void setMetaEntry(QString meta_entry) { m_meta_entry = meta_entry; }
 
-   protected:
+   public slots:
+    /** Stops all currently loading images from modifying the document.
+     *
+     *  This does not stop the ongoing network tasks, it only prevents their result
+     *  from impacting the document any further.
+     */
+    void flush();
+
+   private:
     /** Adds the image to the document, in the given position.
      */
     void parseImage(QTextDocument* doc, QImage image, int posInDocument);
@@ -49,7 +57,8 @@ class VariableSizedImageObject : public QObject, public QTextObjectInterface {
      */
     void loadImage(QTextDocument* doc, const QUrl& source, int posInDocument);
 
+   private:
     QString m_meta_entry;
 
-    QList<QUrl> m_fetching_images;
+    QSet<QUrl> m_fetching_images;
 };