/**
* Return any question id's and warnings if a question does not have exactly 1 correct answer
*
* @return collection
*/
public function warnings()
{
$warnings = new \Illuminate\Database\Eloquent\Collection();
$questions = Question::where('quiz_id', '=', $this->id)->get();
foreach ($questions as $question) {
$number_of_correct_answers = $question->numberOfCorrectAnswers();
if ($number_of_correct_answers != 1) {
$warning = 'Question has ' . $number_of_correct_answers . ' correct answers!';
$warnings->put($question->id, $warning);
}
}
return $warnings;
}