"""Persistence tests
"""
import pickle
import struct
import unittest

from shapely import wkb, wkt
from shapely.geometry import Point


class PersistTestCase(unittest.TestCase):
    def test_pickle(self):

        p = Point(0.0, 0.0)
        data = pickle.dumps(p)
        q = pickle.loads(data)
        assert q.equals(p)

    def test_wkb(self):

        p = Point(0.0, 0.0)
        wkb_big_endian = wkb.dumps(p, big_endian=True)
        wkb_little_endian = wkb.dumps(p, big_endian=False)
        # Regardless of byte order, loads ought to correctly recover the
        # geometry
        assert p.equals(wkb.loads(wkb_big_endian))
        assert p.equals(wkb.loads(wkb_little_endian))

    def test_wkb_dumps_endianness(self):

        p = Point(0.5, 2.0)
        wkb_big_endian = wkb.dumps(p, big_endian=True)
        wkb_little_endian = wkb.dumps(p, big_endian=False)
        assert wkb_big_endian != wkb_little_endian
        # According to WKB specification in section 3.3 of OpenGIS
        # Simple Features Specification for SQL, revision 1.1, the
        # first byte of a WKB representation indicates byte order.
        # Big-endian is 0, little-endian is 1.
        assert wkb_big_endian[0] == 0
        assert wkb_little_endian[0] == 1
        # Check that the doubles (0.5, 2.0) are in correct byte order
        double_size = struct.calcsize("d")
        assert wkb_big_endian[(-2 * double_size) :] == struct.pack(">2d", p.x, p.y)
        assert wkb_little_endian[(-2 * double_size) :] == struct.pack("<2d", p.x, p.y)

    def test_wkt(self):
        p = Point(0.0, 0.0)
        text = wkt.dumps(p)
        assert text.startswith("POINT")
        pt = wkt.loads(text)
        assert pt.equals(p)
