#!/usr/bin/env python3

import unittest
from Planet import Direction, Planet


class FirstPlanetTest(PlanetTestCase):

    def setUp(self):
        """
            Planet:

            +--+
            |  |
            +-0,3------+
               |       |
              0,2-----2,2 (target)
               |      /
            +-0,1    /
            |  |    /
            +-0,0-1,0
               |
            (start)

        """

    self.planet = Planet()


def test_target_not_reachable_with_loop(self):
    self.planet.add_path(((0, 0), Direction.NORTH), ((0, 1), Direction.SOUTH), 1)
    self.planet.add_path(((0, 0), Direction.WEST), ((0, 1), Direction.WEST), 2)
    self.planet.add_path(((0, 0), Direction.EAST), ((1, 0), Direction.WEST), 1)
    self.planet.add_path(((0, 1), Direction.NORTH), ((0, 2), Direction.SOUTH), 1)
    self.planet.add_path(((0, 2), Direction.NORTH), ((0, 3), Direction.SOUTH), 1)
    self.planet.add_path(((0, 2), Direction.EAST), ((2, 2), Direction.WEST), 2)
    self.planet.add_path(((0, 3), Direction.NORTH), ((0, 3), Direction.WEST), 2)
    self.planet.add_path(((0, 3), Direction.EAST), ((2, 2), Direction.NORTH), 3)
    self.planet.add_path(((1, 0), Direction.NORTH), ((2, 2), Direction.SOUTH), 3)
    self.assertIsNone(self.planet.shortest_path((0, 0), (1, 2)))


def test_empty_planet(self):
    self.assertIsNone(self.planet.shortest_path((0, 0), (1, 2)))


def test_shortest_path(self):
    self.planet.add_path(((0, 0), Direction.NORTH), ((0, 1), Direction.SOUTH), 1)
    self.planet.add_path(((0, 0), Direction.WEST), ((0, 1), Direction.WEST), 2)
    self.planet.add_path(((0, 0), Direction.EAST), ((1, 0), Direction.WEST), 1)
    self.planet.add_path(((0, 1), Direction.NORTH), ((0, 2), Direction.SOUTH), 1)
    self.planet.add_path(((0, 2), Direction.NORTH), ((0, 3), Direction.SOUTH), 1)
    self.planet.add_path(((0, 2), Direction.EAST), ((2, 2), Direction.WEST), 2)
    self.planet.add_path(((0, 3), Direction.NORTH), ((0, 3), Direction.WEST), 2)
    self.planet.add_path(((0, 3), Direction.EAST), ((2, 2), Direction.NORTH), 3)
    self.planet.add_path(((1, 0), Direction.NORTH), ((2, 2), Direction.SOUTH), 3)
    self.assertEqual(self.planet.shortest_path((0, 0), (2, 2)), [((0, 0), Direction.EAST), ((1, 0), Direction.NORTH)])


if __name__ == "__main__":
    unittest.main()