Wait till pdfworker finishes before new search, cancel running

TODO

@@ -25,5 +25,6 @@ type:file
 endswith:
 startswith:
 mtime:
-
+tag:
+page:
 SearchWorker::setFilters()

gui/mainwindow.cpp

@@ -121,7 +121,10 @@ void MainWindow::makePdfPreview()
 {
     if(!pdfWorkerThread.isRunning())
         pdfWorkerThread.start();
-    qDeleteAll(ui->scrollAreaWidgetContents->children());
+
+   pdfWorker->cancelAndWait();
+   QCoreApplication::processEvents(); //Process not processed images
+   qDeleteAll(ui->scrollAreaWidgetContents->children());
 
    ui->scrollAreaWidgetContents->setLayout(new QHBoxLayout());
     emit startPdfPreviewGeneration(this->pdfSearchResults, 0.75);

gui/pdfworker.cpp

@@ -15,15 +15,25 @@ Poppler::Document * PdfWorker::document(QString path)
         return this->documentcache.value(path);
 
     Poppler::Document *result = Poppler::Document::load(path);
+    if(result == nullptr)
+    {
+        return nullptr;
+    }
     result->setRenderHint(Poppler::Document::TextAntialiasing);
     this->documentcache.insert(path, result);
     return result;
 }
 void PdfWorker::generatePreviews(QVector<SearchResult> paths, double scalefactor)
 {
+    this->cancelCurrent = false;
+    this->generating = true;
     for(SearchResult &sr : paths)
     {
         Poppler::Document *doc = document(sr.path);
+        if(doc == nullptr)
+        {
+            continue;
+        }
         qDebug() << sr.path;
         if(doc->isLocked())
         {
@@ -39,6 +49,27 @@ void PdfWorker::generatePreviews(QVector<SearchResult> paths, double scalefactor
         preview.previewImage = image;
         preview.documentPath = sr.path;
         emit previewReady(preview);
+        if(this->cancelCurrent.load())
+        {
+
+            break;
+        }
     }
+    isFreeMutex.lock();
+    isFree.wakeOne();
+    isFreeMutex.unlock();
+    generating = false;
     emit previewsFinished();
 }
+
+void PdfWorker::cancelAndWait()
+{
+    if(this->generating.load())
+    {
+        this->cancelCurrent = true;
+
+        isFreeMutex.lock();
+        isFree.wait(&isFreeMutex);
+        isFreeMutex.unlock();
+    }
+}

gui/pdfworker.h

@@ -3,6 +3,9 @@
 #include <QObject>
 #include <QImage>
 #include <QHash>
+#include <QThread>
+#include <QMutex>
+#include <QWaitCondition>
 #include <poppler-qt5.h>
 #include "pdfpreview.h"
 #include "searchresult.h"
@@ -13,8 +16,13 @@ class PdfWorker : public QObject
 private:
     QHash<QString, Poppler::Document *> documentcache;
     Poppler::Document *document(QString path);
+    std::atomic<bool> cancelCurrent { false } ;
+    std::atomic<bool> generating { false };
+    QMutex isFreeMutex;
+    QWaitCondition isFree;
 public:
     PdfWorker();
+    void cancelAndWait();
 public slots:
     void generatePreviews(QVector<SearchResult> paths, double scalefactor);
 signals:

gui/searchworker.cpp

@@ -20,6 +20,13 @@ SearchWorker::SearchWorker(const QString &dbpath)
     queryContent->prepare("SELECT file.path, content.page, file.mtime FROM file INNER JOIN content ON file.id = content.fileid INNER JOIN content_fts ON content.id = content_fts.ROWID WHERE content_fts.content MATCH ? ORDER By file.mtime DESC, content.page ASC");
 }
 
+
+QString normalize(QString str)
+{
+    str = str.replace(" ", " AND ");
+    str = str.replace("|", " OR ");
+    return str;
+}
 void SearchWorker::searchForFile(const QString &query)
 {
     QVector<SearchResult> results;