from operator import attrgetter

from django.test import TestCase

from models import Post, Question, Answer

class OrderWithRespectToTests(TestCase):

    def test_basic(self):

        q1 = Question.objects.create(text="Which Beatle starts with the letter 'R'?")

        q2 = Question.objects.create(text="What is your name?")

        Answer.objects.create(text="John", question=q1)

        Answer.objects.create(text="Jonno", question=q2)

        Answer.objects.create(text="Paul", question=q1)

        Answer.objects.create(text="Paulo", question=q2)

        Answer.objects.create(text="George", question=q1)

        Answer.objects.create(text="Ringo", question=q1)

        # The answers will always be ordered in the order they were inserted.

        self.assertQuerysetEqual(

            q1.answer_set.all(), [

                "John", "Paul", "George", "Ringo",

            ],

            attrgetter("text"),

        )

        # We can retrieve the answers related to a particular object, in the

        # order they were created, once we have a particular object.

        a1 = Answer.objects.filter(question=q1)[0]

        self.assertEqual(a1.text, "John")

        a2 = a1.get_next_in_order()

        self.assertEqual(a2.text, "Paul")

        a4 = list(Answer.objects.filter(question=q1))[-1]

        self.assertEqual(a4.text, "Ringo")

        self.assertEqual(a4.get_previous_in_order().text, "George")

        # Determining (and setting) the ordering for a particular item is also

        # possible.

        id_list = [o.pk for o in q1.answer_set.all()]

        self.assertEqual(a2.question.get_answer_order(), id_list)

        a5 = Answer.objects.create(text="Number five", question=q1)

        # It doesn't matter which answer we use to check the order, it will

        # always be the same.

        self.assertEqual(

            a2.question.get_answer_order(), a5.question.get_answer_order()

        )

        # The ordering can be altered:

        id_list = [o.pk for o in q1.answer_set.all()]

        x = id_list.pop()

        id_list.insert(-1, x)

        self.assertNotEqual(a5.question.get_answer_order(), id_list)

        a5.question.set_answer_order(id_list)

        self.assertQuerysetEqual(

            q1.answer_set.all(), [

                "John", "Paul", "George", "Number five", "Ringo"

            ],

            attrgetter("text")

        )

    def test_recursive_ordering(self):

        p1 = Post.objects.create(title='1')

        p2 = Post.objects.create(title='2')

        p1_1 = Post.objects.create(title="1.1", parent=p1)

        p1_2 = Post.objects.create(title="1.2", parent=p1)

        p2_1 = Post.objects.create(title="2.1", parent=p2)

        p1_3 = Post.objects.create(title="1.3", parent=p1)

        self.assertEqual(p1.get_post_order(), [p1_1.pk, p1_2.pk, p1_3.pk])