Function generateRandomExam

api/src/utils/exam.ts:28–55

(examJson: Exam)

 * @returns An array of randomized questions for the exam.
 */
export function generateRandomExam(examJson: Exam): GeneratedExam {
  const { numberOfQuestionsInExam, questions } = examJson;
  const numberOfAnswersPerQuestion = 5;

  const availableQuestions = shuffleArray(filterDeprecated(questions));
  const examQuestions = availableQuestions.slice(0, numberOfQuestionsInExam);

  const randomizedExam: GeneratedExam = examQuestions.map(
    (question: Question) => {
      const availableCorrectAnswers = filterDeprecated(question.correctAnswers);
      const availableWrongAnswers = shuffleArray(
        filterDeprecated(question.wrongAnswers)
      );
      const correctAnswer = getRandomElement(availableCorrectAnswers);
      const answers = shuffleArray([
        correctAnswer,
        ...availableWrongAnswers.slice(0, numberOfAnswersPerQuestion - 1)
      ]).map(({ id, answer }) => ({ id, answer }));
      return {
        id: question.id,
        question: question.question,
        answers
      };
    }
  );

  return randomizedExam;
}

/**
 * Evaluates a user completed exam.