import unittest

from snakes.engine.perimeter import perimeter_geometry_score

class TestPerimeterGeometryScore(unittest.TestCase):
  def score(self, point, **overrides):
    values = {
      "point": point,
      "current_head": (0, 5),
      "width": 11,
      "height": 11,
      "occupancy": 0.35,
      "snake_length": 12,
      "reachable_space": 80,
      "required_space": 12,
      "liberties": 2,
      "next_options": 2,
      "safe_next_options": 2,
      "tail_escape": True,
      "dead_end": False,
      "losing_head_to_head": False,
    }
    values.update(overrides)
    return perimeter_geometry_score(**values)

  def test_safe_wall_lane_can_outscore_adjacent_inner_lane(self):
    wall = self.score((0, 6))
    inner = self.score((1, 5))

    self.assertGreater(wall, inner)

  def test_unsafe_wall_does_not_receive_perimeter_reward(self):
    safe_wall = self.score((0, 6))
    unsafe_wall = self.score((0, 6), safe_next_options=1)

    self.assertGreater(safe_wall, unsafe_wall + 30.0)

  def test_corner_is_less_attractive_than_straight_edge(self):
    corner = self.score((0, 0), current_head=(0, 1))
    straight_edge = self.score((0, 6))

    self.assertGreater(straight_edge, corner)

  def test_losing_head_to_head_never_gets_perimeter_reward(self):
    safe_wall = self.score((0, 6))
    contested_wall = self.score((0, 6), losing_head_to_head=True)

    self.assertGreater(safe_wall, contested_wall + 30.0)

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