From fa8e351859ce1ad8a9f0573a87cde6e0dc71285c Mon Sep 17 00:00:00 2001
From: Albert S <mail@quitesimple.org>
Date: Mon, 26 Aug 2019 09:20:21 +0200
Subject: [PATCH] paging for pdfpreviews

---
 gui/mainwindow.cpp | 30 +++++++++++++++++++++++-------
 gui/mainwindow.h   |  4 +++-
 gui/mainwindow.ui  | 20 ++++++++++++++++++++
 3 files changed, 46 insertions(+), 8 deletions(-)

diff --git a/gui/mainwindow.cpp b/gui/mainwindow.cpp
index 8e0b33a..99288ef 100644
--- a/gui/mainwindow.cpp
+++ b/gui/mainwindow.cpp
@@ -19,9 +19,10 @@
 MainWindow::MainWindow(QWidget *parent) : QMainWindow(parent), ui(new Ui::MainWindow)
 {
 	ui->setupUi(this);
+	QSettings settings;
 
 	db = QSqlDatabase::addDatabase("QSQLITE");
-	db.setDatabaseName(QSettings().value("dbpath").toString());
+	db.setDatabaseName(settings.value("dbpath").toString());
 	if(!db.open())
 	{
 		qDebug() << "failed to open database";
@@ -33,8 +34,9 @@ MainWindow::MainWindow(QWidget *parent) : QMainWindow(parent), ui(new Ui::MainWi
 	ui->statusBar->addWidget(ui->lblSearchResults);
 	ui->statusBar->addWidget(ui->pdfProcessBar);
 	ui->pdfProcessBar->hide();
-	QSettings settings;
 	ui->comboScale->setCurrentText(settings.value("currentScale").toString());
+	pdfPreviewsPerPage = settings.value("pdfPreviewsPerPage", 20).toInt();
+	ui->spinPdfPreviewPage->setMinimum(1);
 }
 
 void MainWindow::connectSignals()
@@ -64,13 +66,20 @@ void MainWindow::connectSignals()
 	connect(ui->tabWidget, &QTabWidget::currentChanged, this, &MainWindow::tabChanged);
 	connect(ui->comboScale, qOverload<const QString &>(&QComboBox::currentIndexChanged), this,
 			&MainWindow::comboScaleChanged);
+	connect(ui->spinPdfPreviewPage, qOverload<int>(&QSpinBox::valueChanged), this,
+			&MainWindow::spinPdfPreviewPageValueChanged);
+}
+
+void MainWindow::spinPdfPreviewPageValueChanged(int val)
+{
+	makePdfPreview(val);
 }
 
 void MainWindow::comboScaleChanged(QString text)
 {
 	QSettings scaleSetting;
 	scaleSetting.setValue("currentScale", ui->comboScale->currentText());
-	makePdfPreview();
+	makePdfPreview(ui->spinPdfPreviewPage->value());
 }
 bool MainWindow::pdfTabActive()
 {
@@ -104,7 +113,7 @@ void MainWindow::tabChanged()
 	{
 		if(pdfDirty)
 		{
-			makePdfPreview();
+			makePdfPreview(ui->spinPdfPreviewPage->value());
 		}
 		ui->pdfProcessBar->show();
 	}
@@ -195,13 +204,18 @@ void MainWindow::handleSearchResults(const QVector<SearchResult> &results)
 	ui->treeResultsList->resizeColumnToContents(0);
 	ui->treeResultsList->resizeColumnToContents(1);
 	pdfDirty = !this->pdfSearchResults.empty();
+
+	int numpages = ceil(static_cast<double>(this->pdfSearchResults.size()) / pdfPreviewsPerPage);
+	ui->spinPdfPreviewPage->setMinimum(1);
+	ui->spinPdfPreviewPage->setMaximum(numpages);
+	ui->spinPdfPreviewPage->setValue(1);
 	if(pdfTabActive() && pdfDirty)
 	{
-		makePdfPreview();
+		makePdfPreview(1);
 	}
 }
 
-void MainWindow::makePdfPreview()
+void MainWindow::makePdfPreview(int page)
 {
 
 	this->pdfWorkerWatcher.cancel();
@@ -237,8 +251,10 @@ void MainWindow::makePdfPreview()
 		}
 	}
 	PdfWorker worker;
+	int end = pdfPreviewsPerPage;
+	int begin = page * pdfPreviewsPerPage - pdfPreviewsPerPage;
 	this->pdfWorkerWatcher.setFuture(
-		worker.generatePreviews(this->pdfSearchResults, wordsToHighlight, scaleText.toInt() / 100.));
+		worker.generatePreviews(this->pdfSearchResults.mid(begin, end), wordsToHighlight, scaleText.toInt() / 100.));
 	ui->pdfProcessBar->setMaximum(this->pdfWorkerWatcher.progressMaximum());
 	ui->pdfProcessBar->setMinimum(this->pdfWorkerWatcher.progressMinimum());
 }
diff --git a/gui/mainwindow.h b/gui/mainwindow.h
index ad9aa50..b5b5237 100644
--- a/gui/mainwindow.h
+++ b/gui/mainwindow.h
@@ -36,13 +36,14 @@ class MainWindow : public QMainWindow
 	void add(QString path, unsigned int page);
 	QVector<SearchResult> pdfSearchResults;
 	void connectSignals();
-	void makePdfPreview();
+	void makePdfPreview(int page);
 	bool pdfTabActive();
 	void keyPressEvent(QKeyEvent *event) override;
 	unsigned int processedPdfPreviews;
 	void handleSearchResults(const QVector<SearchResult> &results);
 	void handleSearchError(QString error);
 	QSSQuery currentQuery;
+	int pdfPreviewsPerPage;
   private slots:
 	void lineEditReturnPressed();
 	void treeSearchItemActivated(QTreeWidgetItem *item, int i);
@@ -50,6 +51,7 @@ class MainWindow : public QMainWindow
 	void tabChanged();
 	void pdfPreviewReceived(PdfPreview preview);
 	void comboScaleChanged(QString text);
+	void spinPdfPreviewPageValueChanged(int val);
 };
 
 #endif // MAINWINDOW_H
diff --git a/gui/mainwindow.ui b/gui/mainwindow.ui
index 8de1fd7..3cf967d 100644
--- a/gui/mainwindow.ui
+++ b/gui/mainwindow.ui
@@ -148,6 +148,26 @@
             </property>
            </spacer>
           </item>
+          <item>
+           <widget class="QLabel" name="lblPdfPreviewPage">
+            <property name="text">
+             <string>Page:</string>
+            </property>
+           </widget>
+          </item>
+          <item>
+           <widget class="QSpinBox" name="spinPdfPreviewPage">
+            <property name="buttonSymbols">
+             <enum>QAbstractSpinBox::PlusMinus</enum>
+            </property>
+            <property name="accelerated">
+             <bool>false</bool>
+            </property>
+            <property name="showGroupSeparator" stdset="0">
+             <bool>false</bool>
+            </property>
+           </widget>
+          </item>
          </layout>
         </item>
        </layout>