#include "TriviaApp.h"
#include <QDomDocument>
#include <QFile>
#include <QMessageBox>
#include "Question.h"

TriviaApp::TriviaApp(int argc, char* argv[]) :
	QApplication(argc, argv)
{
}

TriviaApp::~TriviaApp()
{
	qDeleteAll(questions);
}

int TriviaApp::exec()
{
	if ( ! loadQuestions() ) return 1;

	printQuestions();

	return 0;
}

inline bool showError(const QString& message)
{
	QMessageBox::critical(0, "Error", message);
	return false;
}

bool TriviaApp::loadQuestions()
{
	QFile file(triviaFilename);
	if ( ! file.open(QIODevice::ReadOnly | QIODevice::Text) )
		return showError( QString("Could not open %1").arg(triviaFilename) );

	QDomDocument document("trivia");
	QString errorMsg;
	int errorLine = 0;
	int errorColumn = 0;
	if ( ! document.setContent(&file, &errorMsg, &errorLine, &errorColumn) )
	{
		file.close();
		return showError(QString("%1:%2.%3: %4")
			.arg(triviaFilename).arg(errorLine).arg(errorColumn).arg(errorMsg));
	}
	file.close();

	QDomElement triviaElement = document.documentElement();
	for( QDomNode node = triviaElement.firstChild(); ! node.isNull(); node = node.nextSibling() )
	{
		QDomElement element = node.toElement(); // try to convert the node to an element.
		if( element.isNull() || element.tagName() != "question" ) continue;

		Question* question = createQuestion(element.attribute("type"));
		if ( ! question->loadFromNode(element) )
		{
			// Hubo una pregunta mala. Que hacer con ella?
			delete question;
			continue;
		}

		questions.append(question);
	}

	return true;
}

void TriviaApp::printQuestions() const
{
	for ( int i = 0; i < questions.count(); ++i )
		questions[i]->print();
}

Question* TriviaApp::createQuestion(const QString& /*type*/)
{
	//if ( type == "single_choice" ) return new SingleChoiceQuestion();
	//if ( type == "numeric" ) return new NumericQuestion();
	//...
	return new Question();
}