1 files changed, 221 insertions, 0 deletions
diff --git a/testapp/exam/models.py b/testapp/exam/models.py
new file mode 100644
index 0000000..717e02e
--- /dev/null
+++ b/testapp/exam/models.py
@@ -0,0 +1,221 @@
+import datetime
+from django.db import models
+from django.contrib.auth.models import User
+
+################################################################################
+class Profile(models.Model):
+    """Profile for a user to store roll number and other details."""
+    user = models.OneToOneField(User)
+    roll_number = models.CharField(max_length=20)
+    institute = models.CharField(max_length=128)
+    department = models.CharField(max_length=64)
+    position = models.CharField(max_length=64)
+
+
+QUESTION_TYPE_CHOICES = (
+        ("python", "Python"),
+        ("bash", "Bash"),
+        ("mcq", "MultipleChoice"),
+        )
+
+################################################################################
+class Question(models.Model):
+    """A question in the database."""
+
+    # A one-line summary of the question.
+    summary = models.CharField(max_length=256)
+
+    # The question text, should be valid HTML.
+    description = models.TextField()
+    
+    # Number of points for the question.
+    points = models.FloatField(default=1.0)
+    
+    # Test cases for the question in the form of code that is run.
+    test = models.TextField(blank=True)
+
+    # Any multiple choice options.  Place one option per line.
+    options = models.TextField(blank=True)
+
+    # The type of question.
+    type = models.CharField(max_length=24, choices=QUESTION_TYPE_CHOICES)
+
+    # Is this question active or not.  If it is inactive it will not be used
+    # when creating a QuestionPaper.
+    active = models.BooleanField(default=True)
+
+    def __unicode__(self):
+        return self.summary
+
+
+################################################################################
+class Answer(models.Model):
+    """Answers submitted by users.
+    """
+    # The question for which we are an answer.
+    question = models.ForeignKey(Question)
+    
+    # The answer submitted by the user.
+    answer = models.TextField()
+
+    # Error message when auto-checking the answer.
+    error = models.TextField()
+
+    # Marks obtained for the answer.  This can be changed by the teacher if the
+    # grading is manual.
+    marks = models.FloatField(default=0.0)
+    
+    # Is the answer correct.
+    correct = models.BooleanField(default=False)
+        
+    def __unicode__(self):
+        return self.answer
+
+################################################################################
+class Quiz(models.Model):
+    """A quiz that students will participate in.  One can think of this 
+    as the "examination" event.
+    """
+    
+    # The starting/ending date of the quiz.
+    start_date = models.DateField("Date of the quiz")
+    
+    # This is always in minutes.
+    duration = models.IntegerField("Duration of quiz in minutes", default=20)
+    
+    # Is the quiz active.  The admin should deactivate the quiz once it is 
+    # complete.
+    active = models.BooleanField(default=True)
+    
+    # Description of quiz.
+    description = models.CharField(max_length=256)
+    
+    class Meta:
+        verbose_name_plural = "Quizzes"
+    
+    def __unicode__(self):
+        desc = self.description or 'Quiz'
+        return '%s: on %s for %d minutes'%(desc, self.start_date, self.duration)
+
+    
+################################################################################
+class QuestionPaper(models.Model):
+    """A question paper for a student -- one per student typically.
+    """
+    # The user taking this question paper.
+    user = models.ForeignKey(User)
+
+    # The user's profile, we store a reference to make it easier to access the
+    # data.
+    profile = models.ForeignKey(Profile)
+    
+    # The Quiz to which this question paper is attached to.
+    quiz = models.ForeignKey(Quiz)
+    
+    # The time when this paper was started by the user.
+    start_time = models.DateTimeField()
+    
+    # User's IP which is logged.
+    user_ip = models.CharField(max_length=15)
+    # Unused currently.
+    key = models.CharField(max_length=10)
+
+    # used to allow/stop a user from retaking the question paper.
+    active = models.BooleanField(default = True)
+    
+    # The questions (a list of ids separated by '|')
+    questions = models.CharField(max_length=128)
+    # The questions successfully answered (a list of ids separated by '|')
+    questions_answered = models.CharField(max_length=128)
+    
+    # All the submitted answers.
+    answers = models.ManyToManyField(Answer)
+
+    # Teacher comments on the question paper.
+    comments = models.TextField()
+    
+    def current_question(self):
+        """Returns the current active question to display."""
+        qs = self.questions.split('|')
+        if len(qs) > 0:
+            return qs[0]
+        else:
+            return ''
+            
+    def questions_left(self):
+        """Returns the number of questions left."""
+        qs = self.questions
+        if len(qs) == 0:
+            return 0
+        else:
+            return qs.count('|') + 1
+            
+    def completed_question(self, question_id):
+        """Removes the question from the list of questions and returns
+        the next."""
+        qa = self.questions_answered
+        if len(qa) > 0:
+            self.questions_answered = '|'.join([qa, str(question_id)])
+        else:
+            self.questions_answered = str(question_id)
+        qs = self.questions.split('|')
+        qs.remove(unicode(question_id))
+        self.questions = '|'.join(qs)
+        self.save()
+        if len(qs) == 0:
+            return ''
+        else:
+            return qs[0]
+
+    def skip(self):
+        """Skip the current question and return the next available question."""
+        qs = self.questions.split('|')
+        if len(qs) == 0:
+            return ''
+        else:
+            # Put head at the end.
+            head = qs.pop(0)
+            qs.append(head)
+            self.questions = '|'.join(qs)
+            self.save()
+            return qs[0]
+            
+    def time_left(self):
+        """Return the time remaining for the user in seconds."""
+        dt = datetime.datetime.now() - self.start_time
+        try:
+            secs = dt.total_seconds()
+        except AttributeError:
+            # total_seconds is new in Python 2.7. :(
+            secs = dt.seconds + dt.days*24*3600
+        total = self.quiz.duration*60.0
+        remain = max(total - secs, 0)
+        return int(remain)
+
+    def get_answered_str(self):
+        """Returns the answered questions, sorted and as a nice string."""
+        qa = self.questions_answered.split('|')
+        answered = ', '.join(sorted(qa))
+        return answered if answered else 'None'
+
+    def get_total_marks(self):
+        """Returns the total marks earned by student for this paper."""
+        return sum([x.marks for x in self.answers.filter(marks__gt=0.0)])
+
+    def get_question_answers(self):
+        """Return a dictionary with keys as questions and a list of the corresponding
+        answers.
+        """
+        q_a = {}
+        for answer in self.answers.all():
+            question = answer.question
+            if question in q_a:
+                q_a[question].append(answer)
+            else:
+                q_a[question] = [answer]
+        return q_a
+    
+    def __unicode__(self):
+        u = self.user
+        return u'Question paper for {0} {1}'.format(u.first_name, u.last_name)
+