gui: Introduce PreviewGeneratorOdt for basic previews of .odt files

gui/previewgeneratorodt.cpp

@@ -0,0 +1,32 @@
+#include <quazip.h>
+#include <quazipfile.h>
+#include "previewgeneratorplaintext.h"
+#include "previewgeneratorodt.h"
+#include "previewresultodt.h"
+#include "../shared/tagstripperprocessor.h"
+
+QSharedPointer<PreviewResult> PreviewGeneratorOdt::generate(RenderConfig config, QString documentPath,
+															unsigned int page)
+{
+	PreviewResultOdt *result = new PreviewResultOdt(documentPath, page);
+
+	QFileInfo info{documentPath};
+
+	QuaZipFile zipFile(documentPath);
+	zipFile.setFileName("content.xml");
+	if(!zipFile.open(QIODevice::ReadOnly))
+	{
+		return QSharedPointer<PreviewResult>(result);
+	}
+	QByteArray entireContent = zipFile.readAll();
+	if(entireContent.isEmpty())
+	{
+		throw LooqsGeneralException("Error while reading content.xml of " + documentPath);
+	}
+	TagStripperProcessor tsp;
+	QString content = tsp.process(entireContent).first().content;
+
+	PreviewGeneratorPlainText plainTextGenerator;
+	result->setText(plainTextGenerator.generatePreviewText(content, config, info.fileName()));
+	return QSharedPointer<PreviewResult>(result);
+}