import unittest

from Geometry import *


class TwoVectorTest(unittest.TestCase):

    def testAdd(self):
        """
        Add a couple of test vectors and check that they sum
        correctly.
        """        
        v1 = TwoVector(0,0)
        v2 = TwoVector(100, -19)
        self.assertTrue(v2 == (v1+v2))

        v1 = TwoVector(23, -10)
        v2 = TwoVector(-23, 10)
        zero = TwoVector(0, 0)
        self.assertTrue((v1+v2) == zero)

        
    def testDotProduct(self):
        """
        The dot product of a vector v with a vector to which it's
        perpendicular, v_perp, should always be zero.

        The dot product of any vector with the zero vector should be
        zero.
        """        
        v1 = TwoVector(235, -2352)
        v2 = TwoVector(9382335.024, -235235.1242)
        self.assertEqual(0, v1.dot_product(v1.perpendicular()))
        self.assertEqual(0, v2.dot_product(v2.perpendicular()))

        zero = TwoVector(0, 0)
        self.assertEqual(0, v1.dot_product(zero))



class PolygonTest(unittest.TestCase):

    def testEquals(self):
        """
        We defined our own __eq__ method; make sure it works.
        """
        unit_square1 = Polygon([ (0,0), (1,0), (1,1), (0,1) ])
        unit_square2 = Polygon([ (0,0), (1,0), (1,1), (0,1) ])
        self.assertTrue(unit_square1 == unit_square2)

        hexagon = Polygon([ (1,0),
                            (0.5, sqrt(3)/2.0),
                            (-0.5, sqrt(3)/2.0),
                            (-1, 0),
                            (-0.5, -sqrt(3)/2.0),
                            (0.5, -sqrt(3)/2.0) ])

        self.assertFalse(unit_square1 == hexagon)

        
    def testDrag(self):
        """
        Drag the unit square 5 units to the right.
        """
        unit_square = Polygon([ (0,0), (1,0), (1,1), (0,1) ])
        v = TwoVector(5,0)
        result = unit_square.drag(v)
        expected_result = Polygon([ (0,0), (6,0), (6,1), (0,1) ])
        self.assertTrue(result == expected_result)



    def testDragVertices(self):
        """
        A diamond shape has nice drag vertices which we can calculate
        by hand.        
        """
        diamond = Polygon([ (0,1), (-1,0), (0,-1), (1,0) ])

        # First, we drag it to the right along the x-axis.
        drag_vector = TwoVector(5,0)
        dvs = set(diamond.drag_vertices(drag_vector))
        expected_dvs = set([(0,1), (0,-1)])
        self.assertTrue(dvs == expected_dvs)

        # Now, drag it up.
        drag_vector = TwoVector(0,5)
        dvs = set(diamond.drag_vertices(drag_vector))
        expected_dvs = set([(1,0), (-1,0)])
        self.assertTrue(dvs == expected_dvs)

        
def suite():
    suite = unittest.TestSuite()
    suite.addTest(unittest.makeSuite(TwoVectorTest))
    suite.addTest(unittest.makeSuite(PolygonTest))
    return suite