/// <summary>
/// Add question to existing which is not assigned to test.
/// </summary>
/// <param name="testId"></param>
/// <param name="question"></param>
/// <returns>Returns id of new question</returns>
public async Task <int> AddQuestionAsync(int testId, QuestionDto question)
{
Test test = await context.Tests.FindAsync(testId);
test.ThrowIfNull(new InvalidOperationException($"Test with id {testId} does not exists"));
question.ThrowIfNull(new ArgumentNullException(nameof(question)));
await ThrowIfTestAssignedToUserAsync(test);
Question newQuestion = new Question();
question.UpdateEntity(newQuestion);
if (question.QuestionTypeId == QuestionTypeEnum.Closed)
{
List <QuestionAnswerOption> options = new List <QuestionAnswerOption>(question.Options.Count);
foreach (QuestionAnswerOptionDto answerOption in question.Options)
{
QuestionAnswerOption option = new QuestionAnswerOption();
answerOption.UpdateEntity(option);
options.Add(option);
}
newQuestion.QuestionAnswerOptions = options;
}
test.Questions.Add(newQuestion);
await context.SaveChangesAsync();
return(newQuestion.Id);
}
/// <summary>
/// Add new answer
/// </summary>
/// <param name="answer"></param>
/// <returns>Returns id of answer</returns>
public async Task <int> AddAnswerAsync(AnswerDto answer)
{
/**
* Internally answer exists but with are not accepted
* It's made to manage which questions have UserTest object
*
*/
Answer existingAnswer = await context.Answers
.Include(a => a.UserTest)
.Include(a => a.Question.QuestionAnswerOptions)
.Where(a => a.UserTestId == answer.UserTestId)
.Where(a => a.QuestionId == answer.QuestionId)
.FirstOrDefaultAsync();
existingAnswer.ThrowIfNull(new InvalidOperationException(
$"Answer with {nameof(answer.UserTestId)} {answer.UserTestId} and {nameof(answer.QuestionId)} {answer.QuestionId} does not exists")
);
ThrowIfTestAlreadyEnded(existingAnswer.UserTest);
// only Closed questions can have more than one right answer
if (existingAnswer.Question.RightAnswers != 1 &&
existingAnswer.Question.QuestionTypeId == QuestionTypeEnum.Closed)
{
QuestionAnswerOption option = existingAnswer.Question
.QuestionAnswerOptions
.Where(q => q.Content == answer.Content) // it's closed question. content should be the same
.FirstOrDefault();
if (existingAnswer.IsAccepted) // add new
{
Answer newAnswer = new Answer()
{
IsAccepted = true,
IsCorrect = option == null ? false : true,
QuestionId = answer.QuestionId,
UserTestId = answer.UserTestId,
Content = answer.Content
};
context.Answers.Add(newAnswer);
}
else
{
existingAnswer.IsAccepted = true;
}
}
else // is open question
{
existingAnswer.IsCorrect = null;
existingAnswer.IsAccepted = true;
}
await context.SaveChangesAsync();
return(existingAnswer.Id);
}
/// <summary>
/// Creates new test
/// </summary>
/// <param name="test"></param>
/// <returns>Returns TestId of supplied test</returns>
public async Task <int> CreateTestAsync(TestDto test)
{
ThrowIfTestIsInvalid(test);
Test newTest = new Test();
test.UpdateEntity(newTest);
List <Question> testQuestions = new List <Question>(test.Questions.Count);
foreach (QuestionDto questionDto in test.Questions)
{
ThrowIfQuestionIsInvalid(questionDto);
// if questions for passing is zero, than it is like quiz. Whatewer you will pass is.
// if questons count is zero, than current test should contains them all
// questions count in test.
if (test.QuestionsCount == 0)
{
newTest.QuestionsCount++;
}
Question question = new Question();
questionDto.UpdateEntity(question);
if (questionDto.QuestionTypeId == QuestionTypeEnum.Closed)
{
List <QuestionAnswerOption> options = new List <QuestionAnswerOption>(questionDto.Options.Count);
foreach (QuestionAnswerOptionDto answerOption in questionDto.Options)
{
QuestionAnswerOption option = new QuestionAnswerOption();
answerOption.UpdateEntity(option);
options.Add(option);
}
question.QuestionAnswerOptions = options;
}
testQuestions.Add(question);
}
testQuestions.ForEach(q => newTest.Questions.Add(q));
context.Tests.Add(newTest);
await context.SaveChangesAsync();
return(newTest.Id);
}
internal void CopyEntityData(QuestionAnswerOption entity)
{
this.Id = entity.Id;
this.Content = entity.Content;
this.IsCorrect = entity.IsCorrect;
}
internal void UpdateEntity(QuestionAnswerOption entity)
{
entity.Id = this.Id;
entity.Content = this.Content;
entity.IsCorrect = this.IsCorrect;
}
internal QuestionAnswerOptionDto(QuestionAnswerOption entity)
{
CopyEntityData(entity);
}
