private void LoadQuestions(ISessionParameters parameters)
{
//TODO: switch to factory pattern
ITicketLoader loader = new TicketLoader();
Tickets = loader.LoadTickets(parameters);
}
public static ParametersValidationResult CreateSession(ISessionParameters parameters, out ISession session)
{
ParametersValidator validator = new ParametersValidator(parameters);
var validationResult = validator.Validate();
if (validationResult == ParametersValidationResult.Valid)
{
session = new Session(parameters);
System.Diagnostics.Debug.WriteLine("validtionResult: {0}", validationResult);
}
else
{
session = null;
}
return(validationResult);
}
public IEnumerable <ITicket> LoadTickets(ISessionParameters parameters)
{
if (parameters.Mode == Enums.QuestionsGenerationMode.Questions)
{
return(parameters.Questions.GroupBy(question => question.Ticket.Number, question => question).Select(group =>
{
var ticket = new Ticket();
foreach (var q in group.OfType <Question>())
{
q.Ticket = ticket;
}
ticket.Questions = group;
ticket.Number = group.Key;
return ticket;
}).ToArray());
}
SQLiteDataAccessor dataAccessor = null;
try {
dataAccessor = new SQLiteDataAccessor();
Tickets[] selectedTickets;
IEnumerable <Questions> questionList;
if (new Enums.QuestionsGenerationMode[] { Enums.QuestionsGenerationMode.RandomTicket, Enums.QuestionsGenerationMode.SelectedTickets }.Contains(parameters.Mode))
{
if (parameters.Mode == Enums.QuestionsGenerationMode.RandomTicket)
{
var tickets = dataAccessor.CreateQuery <Tickets>();
Random rand = new Random();
selectedTickets = new Tickets[] { tickets.ElementAt(rand.Next(tickets.Count())) };
}
else
{
selectedTickets = dataAccessor.CreateQuery <Tickets>().Where(ticket => parameters.TicketNums.Contains(ticket.num)).ToArray();
}
questionList = dataAccessor.CreateQuery <Questions>().Where(question => selectedTickets.Any(ticket => ticket.id == question.ticket_id));
}
else if (parameters.Mode == Enums.QuestionsGenerationMode.ExamTicket)
{
var tickets = dataAccessor.CreateQuery <Tickets>();
selectedTickets = new Tickets[] { tickets.ElementAt(0) };
Random rnd = new Random();
var randomTickets = Enumerable.Range(1, GlobalConstants.ticketsCount).OrderBy(i => rnd.Next()).Select((item, index) => new { id = index, num = item }).Take(GlobalConstants.questionsCount).ToArray();
var randomQuestions = Enumerable.Range(1, GlobalConstants.questionsCount).OrderBy(i => rnd.Next()).Select((item, index) => new { id = index, num = item }).ToArray();
questionList = dataAccessor.CreateQuery <Questions>().Join(randomTickets, question => question.ticket_id, ticket => ticket.num, (question, ticket) => new { Id = ticket.id, Question = question }).Where(question => question.Question.num == randomQuestions.ElementAt(question.Id).num).OrderBy(item => item.Question.num).Select(i => i.Question);
}
else
{
throw new NotImplementedException(String.Format("Not supported mode", parameters.Mode));
}
var questionIdList = questionList.Select(question => question.id).ToArray();
var answerList = dataAccessor.CreateQuery <Answers>().Where(answer => questionIdList.Contains(answer.question_id));
var itickets = selectedTickets.Select(ticket => {
var iticket = new Ticket {
Number = ticket.num
};
var iticketQuestion = parameters.Mode != Enums.QuestionsGenerationMode.ExamTicket ? questionList.Where(question => question.ticket_id == ticket.id) : questionList;
iticket.Questions = iticketQuestion.Select(question => {
var iquestion = new Question {
Ticket = iticket,
Number = question.num,
Image = question.image,
Text = question.question
};
iquestion.Answers = answerList.Where(answer => answer.question_id == question.id).Select(answer => {
var ianswer = new Answer()
{
Question = iquestion,
IsRight = answer.is_right,
Text = answer.answer,
};
return(ianswer);
}).ToArray();
return(iquestion);
}).ToArray();
return(iticket);
}).ToArray();
if (parameters.Shuffle)
{
Random rand = new Random();
foreach (var iticket in itickets)
{
iticket.Questions = iticket.Questions.OrderBy(iquestion => rand.Next()).ToArray();
}
}
return(itickets);
} catch {
throw;
} finally {
if (dataAccessor != null)
{
dataAccessor.Dispose();
}
}
}
internal Session(ISessionParameters parameters)
{
mode = parameters.Mode;
LoadQuestions(parameters);
}
internal ParametersValidator(ISessionParameters parameters)
{
this.parameters = parameters;
}
