#include <iostream>

#include <QApplication>

#include <QThread>

#include <relpipe/cli/CLI.h>

#include <relpipe/cli/RelpipeCLIException.h>

#include <relpipe/reader/Factory.h>

#include <relpipe/reader/RelationalReader.h>

#include <relpipe/reader/RelpipeReaderException.h>

#include "RelpipeChartMainWindow.h"

#include "QtRelationalReaderStringHadler.h"

using namespace relpipe::cli;

using namespace relpipe::reader;

// signal/slot parameters must be declared here and registered with qRegisterMetaType()

Q_DECLARE_METATYPE(string_t)

Q_DECLARE_METATYPE(std::vector<AttributeMetadata>)

class RelationalReaderThread : public QThread {

private:

	std::shared_ptr<RelationalReader> reader;

public:

	// TODO: better background thread; lambda?

	RelationalReaderThread(std::shared_ptr<RelationalReader> reader) :

	reader(reader) {

		setTerminationEnabled(true);

	}

	void run() {

		try {

			reader->process();

		} catch (RelpipeReaderException& e) {

			// TODO: handle exception, show error dialog

			std::wcerr << L"RelpipeReaderException: " << e.getMessge() << std::endl;

		}

	}

};

int main(int argc, char**argv) {

	CLI cli(argc, argv);

	// TODO: argument name collisions? Filter arguments? Use prefix for Qt? Qt: -title, -style, -geometry

	QApplication app(argc, argv);

	std::shared_ptr<RelationalReader> reader(Factory::create(std::cin));

	int resultCode = CLI::EXIT_CODE_UNEXPECTED_ERROR;

	RelpipeChartMainWindow window;

	window.show();

	RelationalReaderThread t(reader);

	// Proxy that passes calls from the background thread to the GUI thread using signal-slot mechanism:

	QtRelationalReaderStringHadler handler(&t); // &t instead of handler.moveToThread(&t); // QObject::moveToThread: Cannot move objects with a parent

	// see Q_DECLARE_METATYPE above

	qRegisterMetaType<string_t>();

	qRegisterMetaType<std::vector < AttributeMetadata >> ();

	QObject::connect(&handler, &QtRelationalReaderStringHadler::startRelationReceived, &window, &RelpipeChartMainWindow::startRelation, Qt::ConnectionType::QueuedConnection);

	QObject::connect(&handler, &QtRelationalReaderStringHadler::attributeReceived, &window, &RelpipeChartMainWindow::attribute, Qt::ConnectionType::QueuedConnection);

	QObject::connect(&handler, &QtRelationalReaderStringHadler::endOfPipeReceived, &window, &RelpipeChartMainWindow::endOfPipe, Qt::ConnectionType::QueuedConnection);

	reader->addHandler(&handler);

	// Start background thread

	t.start();

	int qtResultCode = app.exec();

	if (qtResultCode == 0) {

		resultCode = CLI::EXIT_CODE_SUCCESS;

	} else {

		// TODO: report and log Qt errors if any

	}

	if (t.isRunning()) {

		std::wcerr << L"Background RelationalReader thread is still running → terminate()" << std::endl;

		t.terminate();

		std::wcerr << L"Background RelationalReader thread was terminated → wait()" << std::endl;

		t.wait();

		std::wcerr << L"Background RelationalReader thread wait() finished" << std::endl;

	}

	return resultCode;

}