// Private helper function, that updates given Subject's LastUpdatedTime attribute
// and changes its database state to 'Modified'.
private void UpdateSubjectTime(Subject s)
{
s.UpdateLastUpdatedTime();
db.Entry(s).State = EntityState.Modified;
}
// Private function used by POST Edit method. It is the major part of that method,
// since it is responsible for the actual edition of an existing RegularTask (and its Answer).
// This function returns a proper ActionResult depending whether the action was successful
// or failed at some point.
private ActionResult EditTaskInternal(RegularTask regulartask, Subject sub, int isAnswerChanged,
string answerType, string valueAns, string textAns, IList<string> multiChoiceList,
IList<string> multiAnswerList, ICollection<string> singleChoiceList, int singleCorrectNo)
{
// First let's see if the answer for the task is being changed or not.
// If it's not then we have an easy case to deal with.
if (isAnswerChanged == 0)
{
UpdateSubjectTime(sub);
regulartask.CorrectAnswers = 0;
regulartask.Attempts = 0;
db.Entry(regulartask).State = EntityState.Modified;
db.SaveChanges();
return RedirectToAction("Details", "Subject", new { id = regulartask.SubjectID });
}
// Variable holding answer that belongs to the task
var ans = db.Answers.Find(regulartask.ID);
// And now let's cope with the case when the answer is being changed as well as the task.
switch (answerType)
{
case Answer.SINGLE_VALUE_ANSWER:
if (String.IsNullOrEmpty(valueAns))
{
// In this case we want to reload the Edit page with the original RegularTask
return ReloadPageWithStatement(db.RegularTasks.Find(regulartask.ID), answerType, sub.Name, sub.ID);
}
if (ans.className() == answerType)
{
// We don't have to create a completely new Answer, only update the current one
((SingleValueAnswer)ans).Value = valueAns;
db.Entry(ans).State = EntityState.Modified;
}
else
{
// Delete previous answer and create new SingleValueAnswer
removeOldChoices(ans.className(), regulartask.ID);
db.Answers.Remove(ans);
db.SaveChanges();
var singleValueAnswer = new SingleValueAnswer(valueAns) { TaskID = regulartask.ID };
db.SingleValueAnswers.Add(singleValueAnswer);
}
break;
case Answer.TEXT_ANSWER:
if (String.IsNullOrEmpty(textAns))
{
// In this case we want to reload the Edit page with the original RegularTask
return ReloadPageWithStatement(db.RegularTasks.Find(regulartask.ID), answerType, sub.Name, sub.ID);
}
if (ans.className() == answerType)
{
// We don't have to create a completely new Answer, only update the current one
((TextAnswer)ans).Text = textAns;
db.Entry(ans).State = EntityState.Modified;
}
else
{
// Delete previous answer and create new TextAnswer
removeOldChoices(ans.className(), regulartask.ID);
db.Answers.Remove(ans);
db.SaveChanges();
var textAnswer = new TextAnswer(textAns) { TaskID = regulartask.ID };
db.TextAnswers.Add(textAnswer);
}
break;
case Answer.SINGLE_CHOICE_ANSWER:
if (singleCorrectNo >= singleChoiceList.Count || singleCorrectNo < 0)
{
throw new RetryLimitExceededException("The number of the correct Choice for SingleChoiceAnswer is beyond valid range.");
}
// Case when we haven't got any valid Choices for the SingleChoiceAnswer or some choices are empty
if (singleChoiceList.Count == 0 || singleChoiceList.Count(String.IsNullOrEmpty) != 0)
{
// In this case we want to reload the Edit page with the original RegularTask
return ReloadPageWithStatement(db.RegularTasks.Find(regulartask.ID), answerType, sub.Name, sub.ID);
}
if (ans.className() == answerType)
{
// We don't have to create a completely new Answer, only update the current one
((SingleChoiceAnswer)ans).CorrectAnswer = singleCorrectNo;
db.Entry(ans).State = EntityState.Modified;
// Let's remove old choices ...
removeOldChoices(ans.className(), regulartask.ID);
// ... and add new ones
foreach (var singleChoice in singleChoiceList.Select(s => new SingleChoice(s) { SingleChoiceAnswerID = regulartask.ID }))
{
singleChoice.SingleChoiceAnswerID = regulartask.ID;
db.SingleChoices.Add(singleChoice);
}
}
else
{
// Delete previous answer and create new SingleChoiceAnswer
removeOldChoices(ans.className(), regulartask.ID);
db.Answers.Remove(ans);
db.SaveChanges();
var singleChoiceAnswer = new SingleChoiceAnswer(singleCorrectNo) { TaskID = regulartask.ID };
db.SingleChoiceAnswers.Add(singleChoiceAnswer);
foreach (var singleChoice in singleChoiceList.Select(s => new SingleChoice(s) { SingleChoiceAnswerID = regulartask.ID }))
{
db.SingleChoices.Add(singleChoice);
}
}
break;
case Answer.MULTIPLE_CHOICE_ANSWER:
if (multiChoiceList.Count != multiAnswerList.Count)
{
throw new RetryLimitExceededException("The number of Options doesn't equal the number of true-false answers.");
}
// Case when we haven't got any valid Choices for the MultiChoiceAnswer
if (multiChoiceList.Count(t => !String.IsNullOrEmpty(t)) == 0)
{
// In this case we want to reload the Edit page with the original RegularTask
return ReloadPageWithStatement(db.RegularTasks.Find(regulartask.ID), answerType, sub.Name, sub.ID);
}
if (ans.className() == answerType)
{
// We don't have to create a completely new Answer, only update the current one
// Let's remove old choices ...
removeOldChoices(ans.className(), regulartask.ID);
// ... and add new ones
for (var i = 0; i < multiChoiceList.Count; i++)
{
// No safety check whether the values send by POST are valid ones ('True' and 'False' are valid).
// Every invalid value will be interpreted as 'False'
var tempAns = (multiAnswerList[i].Equals("True", StringComparison.OrdinalIgnoreCase));
var multiChoice = new MultiChoice(multiChoiceList[i], tempAns) { MultipleChoiceAnswerID = regulartask.ID };
db.MultiChoices.Add(multiChoice);
}
}
else
{
// Delete previous answer and create new MultipleChoiceAnswer
removeOldChoices(ans.className(), regulartask.ID);
db.Answers.Remove(ans);
db.SaveChanges();
var multiChoiceAnswer = new MultipleChoiceAnswer { TaskID = regulartask.ID };
db.MultipleChoiceAnswers.Add(multiChoiceAnswer);
for (var i = 0; i < multiChoiceList.Count; i++)
{
// No safety check whether the values send by POST are valid ones ('True' and 'False' are valid).
// Every invalid value will be interpreted as 'False'
var tempAns = (multiAnswerList[i].Equals("True", StringComparison.OrdinalIgnoreCase));
var multiChoice = new MultiChoice(multiChoiceList[i], tempAns) { MultipleChoiceAnswerID = regulartask.ID };
db.MultiChoices.Add(multiChoice);
}
}
break;
}
UpdateSubjectTime(sub);
regulartask.CorrectAnswers = 0;
regulartask.Attempts = 0;
db.Entry(regulartask).State = EntityState.Modified;
db.SaveChanges();
return RedirectToAction("Details", "Subject", new { id = regulartask.SubjectID });
}