#include <QApplication>
#include <QDebug>
#include <QFrame>
#include <QVBoxLayout>
#include <QWidget>
#include <QTimer>
#include <QFont>
#include <QFontMetrics>

#include <Qt3DRender/QCamera>
#include <Qt3DRender/QCameraLens>
#include <Qt3DRender/QRenderSettings>
#include <Qt3DExtras/Qt3DWindow>
#include <Qt3DExtras/QOrbitCameraController>
#include <Qt3DExtras/QText2DEntity>

int main(int argc, char* argv[])
{
	QApplication a(argc, argv);

	auto view = new Qt3DExtras::Qt3DWindow();
	auto renderSettings = view->renderSettings();
	renderSettings->setRenderPolicy(Qt3DRender::QRenderSettings::Always);

	auto rootEntity = new Qt3DCore::QEntity();
	view->setRootEntity(rootEntity);

	auto camera = view->camera();
	camera->lens()->setPerspectiveProjection(45.0f, 1., 0.1f, 10000.0f);
	camera->setPosition(QVector3D(0, 0, 5));
	camera->setUpVector(QVector3D(0, 1, 0));
	camera->setViewCenter(QVector3D(0, 0, 0));

	auto camController = new Qt3DExtras::QOrbitCameraController(rootEntity);
	camController->setCamera(camera);

	auto pointSize = 15.f;
	auto text = QString::fromLatin1("ValidString");
	auto emptyText = QString::fromLatin1("");
	auto anotherText = QString::fromLatin1("Arial");
	QFont font;
	font.setFamily("Arial");
	font.setPointSizeF(pointSize);

	auto sampleTextEntity = new Qt3DCore::QEntity(rootEntity);
	auto textMesh = new Qt3DExtras::QText2DEntity(/*sampleTextEntity*/);
	textMesh->setParent(sampleTextEntity);
	textMesh->setFont(font);
	textMesh->setColor(Qt::black);

	QFontMetricsF fontMetrics(textMesh->font());
	auto boundingRect = fontMetrics.boundingRect(QRectF(), Qt::AlignLeft | Qt::AlignTop, text);
	textMesh->setWidth(boundingRect.width());
	textMesh->setHeight(boundingRect.height());
	textMesh->setText(text);

	auto container = QWidget::createWindowContainer(view);
	QFrame frame;
	frame.setLayout(new QVBoxLayout);
	frame.layout()->addWidget(container);
	frame.resize(QSize(400, 300));

	QTimer::singleShot(100, [&]() {
		camera->viewAll();
	});
	QTimer::singleShot(3000, [&]() {
		textMesh->setText(emptyText);
	});
	QTimer::singleShot(4000, [&]() {
		textMesh->setText(anotherText);
	});

	frame.show();
	return a.exec();
}