import math
from math import pi
import numpy.testing as nt
import unittest

from spatialmath import *
from spatialmath.base import *
from spatialmath.super_pose import SMPose

import numpy as np
from math import pi, sin, cos


def qcompare(x, y):
    if isinstance(x, Quaternion):
        x = x.vec
    elif isinstance(x, SMPose):
        x = x.A
    if isinstance(y, Quaternion):
        y = y.vec
    elif isinstance(y, SMPose):
        y = y.A
    nt.assert_array_almost_equal(x, y)

# straight port of the MATLAB unit tests


class TestUnitQuaternion(unittest.TestCase):

    def test_constructor(self):
        nt.assert_array_almost_equal(UnitQuaternion().vec, np.r_[1, 0, 0, 0])

        nt.assert_array_almost_equal(UnitQuaternion.Rx(90, 'deg').vec, np.r_[1, 1, 0, 0] / math.sqrt(2))
        nt.assert_array_almost_equal(UnitQuaternion.Rx(-90, 'deg').vec, np.r_[1, -1, 0, 0] / math.sqrt(2))
        nt.assert_array_almost_equal(UnitQuaternion.Ry(90, 'deg').vec, np.r_[1, 0, 1, 0] / math.sqrt(2))
        nt.assert_array_almost_equal(UnitQuaternion.Ry(-90, 'deg').vec, np.r_[1, 0, -1, 0] / math.sqrt(2))
        nt.assert_array_almost_equal(UnitQuaternion.Rz(90, 'deg').vec, np.r_[1, 0, 0, 1] / math.sqrt(2))
        nt.assert_array_almost_equal(UnitQuaternion.Rz(-90, 'deg').vec, np.r_[1, 0, 0, -1] / math.sqrt(2))

    def test_constructor(self):

        qcompare(UnitQuaternion(), [1, 0, 0, 0])

        # from S
        qcompare(UnitQuaternion([1, 0, 0, 0]), np.r_[1, 0, 0, 0])
        qcompare(UnitQuaternion([0, 1, 0, 0]), np.r_[0, 1, 0, 0])
        qcompare(UnitQuaternion([0, 0, 1, 0]), np.r_[0, 0, 1, 0])
        qcompare(UnitQuaternion([0, 0, 0, 1]), np.r_[0, 0, 0, 1])

        qcompare(UnitQuaternion([2, 0, 0, 0]), np.r_[1, 0, 0, 0])
        qcompare(UnitQuaternion([-2, 0, 0, 0]), np.r_[-1, 0, 0, 0])

        # from [S,V]
        qcompare(UnitQuaternion(1, [0, 0, 0]), np.r_[1, 0, 0, 0])
        qcompare(UnitQuaternion(0, [1, 0, 0]), np.r_[0, 1, 0, 0])
        qcompare(UnitQuaternion(0, [0, 1, 0]), np.r_[0, 0, 1, 0])
        qcompare(UnitQuaternion(0, [0, 0, 1]), np.r_[0, 0, 0, 1])

        qcompare(UnitQuaternion(2, [0, 0, 0]), np.r_[1, 0, 0, 0])
        qcompare(UnitQuaternion(-2, [0, 0, 0]), np.r_[-1, 0, 0, 0])

        # from R

        qcompare(UnitQuaternion(np.eye(3)), [1, 0, 0, 0])

        qcompare(UnitQuaternion(rotx(pi / 2)), np.r_[1, 1, 0, 0] / math.sqrt(2))
        qcompare(UnitQuaternion(roty(pi / 2)), np.r_[1, 0, 1, 0] / math.sqrt(2))
        qcompare(UnitQuaternion(rotz(pi / 2)), np.r_[1, 0, 0, 1] / math.sqrt(2))

        qcompare(UnitQuaternion(rotx(-pi / 2)), np.r_[1, -1, 0, 0] / math.sqrt(2))
        qcompare(UnitQuaternion(roty(-pi / 2)), np.r_[1, 0, -1, 0] / math.sqrt(2))
        qcompare(UnitQuaternion(rotz(-pi / 2)), np.r_[1, 0, 0, -1] / math.sqrt(2))

        qcompare(UnitQuaternion(rotx(pi)), np.r_[0, 1, 0, 0])
        qcompare(UnitQuaternion(roty(pi)), np.r_[0, 0, 1, 0])
        qcompare(UnitQuaternion(rotz(pi)), np.r_[0, 0, 0, 1])

        # from SO3

        qcompare(UnitQuaternion(SO3()), np.r_[1, 0, 0, 0])

        qcompare(UnitQuaternion(SO3.Rx(pi / 2)), np.r_[1, 1, 0, 0] / math.sqrt(2))
        qcompare(UnitQuaternion(SO3.Ry(pi / 2)), np.r_[1, 0, 1, 0] / math.sqrt(2))
        qcompare(UnitQuaternion(SO3.Rz(pi / 2)), np.r_[1, 0, 0, 1] / math.sqrt(2))

        qcompare(UnitQuaternion(SO3.Rx(-pi / 2)), np.r_[1, -1, 0, 0] / math.sqrt(2))
        qcompare(UnitQuaternion(SO3.Ry(-pi / 2)), np.r_[1, 0, -1, 0] / math.sqrt(2))
        qcompare(UnitQuaternion(SO3.Rz(-pi / 2)), np.r_[1, 0, 0, -1] / math.sqrt(2))

        qcompare(UnitQuaternion(SO3.Rx(pi)), np.r_[0, 1, 0, 0])
        qcompare(UnitQuaternion(SO3.Ry(pi)), np.r_[0, 0, 1, 0])
        qcompare(UnitQuaternion(SO3.Rz(pi)), np.r_[0, 0, 0, 1])

        # vector of SO3
        qcompare(UnitQuaternion([SO3.Rx(pi / 2), SO3.Ry(pi / 2), SO3.Rz(pi / 2)]), np.array([[1, 1, 0, 0], [1, 0, 1, 0], [1, 0, 0, 1]]) / math.sqrt(2))

        # from T
        qcompare(UnitQuaternion(trotx(pi / 2)), np.r_[1, 1, 0, 0] / math.sqrt(2))
        qcompare(UnitQuaternion(troty(pi / 2)), np.r_[1, 0, 1, 0] / math.sqrt(2))
        qcompare(UnitQuaternion(trotz(pi / 2)), np.r_[1, 0, 0, 1] / math.sqrt(2))

        qcompare(UnitQuaternion(trotx(-pi / 2)), np.r_[1, -1, 0, 0] / math.sqrt(2))
        qcompare(UnitQuaternion(troty(-pi / 2)), np.r_[1, 0, -1, 0] / math.sqrt(2))
        qcompare(UnitQuaternion(trotz(-pi / 2)), np.r_[1, 0, 0, -1] / math.sqrt(2))

        qcompare(UnitQuaternion(trotx(pi)), np.r_[0, 1, 0, 0])
        qcompare(UnitQuaternion(troty(pi)), np.r_[0, 0, 1, 0])
        qcompare(UnitQuaternion(trotz(pi)).vec, np.r_[0, 0, 0, 1])

        # # vectorised forms of R, T
        # R = []; T = []
        # for theta in [-pi/2, 0, pi/2, pi]:
        #     R = cat(3, R, rotx(theta), roty(theta), rotz(theta))
        #     T = cat(3, T, trotx(theta), troty(theta), trotz(theta))

        # nt.assert_array_almost_equal(UnitQuaternion(R).R, R)
        # nt.assert_array_almost_equal(UnitQuaternion(T).T, T)

        # copy constructor
        q = UnitQuaternion(rotx(0.3))
        qcompare(UnitQuaternion(q), q)

    def test_concat(self):
        u = UnitQuaternion()
        uu = UnitQuaternion([u, u, u, u])

        self.assertIsInstance(uu, UnitQuaternion)
        self.assertEqual(len(uu), 4)

    def test_string(self):

        u = UnitQuaternion()

        s = str(u)
        self.assertIsInstance(s, str)
        self.assertTrue(s.endswith(' >>'))
        self.assertEqual(s.count('\n'), 0)

        q = UnitQuaternion.Rx([0.3, 0.4, 0.5])
        s = str(q)
        self.assertIsInstance(s, str)
        self.assertEqual(s.count('\n'), 2)

    def test_properties(self):

        u = UnitQuaternion()

        # s,v
        nt.assert_array_almost_equal(UnitQuaternion([1, 0, 0, 0]).s, 1)
        nt.assert_array_almost_equal(UnitQuaternion([1, 0, 0, 0]).v, [0, 0, 0])

        nt.assert_array_almost_equal(UnitQuaternion([0, 1, 0, 0]).s, 0)
        nt.assert_array_almost_equal(UnitQuaternion([0, 1, 0, 0]).v, [1, 0, 0])

        nt.assert_array_almost_equal(UnitQuaternion([0, 0, 1, 0]).s, 0)
        nt.assert_array_almost_equal(UnitQuaternion([0, 0, 1, 0]).v, [0, 1, 0])

        nt.assert_array_almost_equal(UnitQuaternion([0, 0, 0, 1]).s, 0)
        nt.assert_array_almost_equal(UnitQuaternion([0, 0, 0, 1]).v, [0, 0, 1])

        # R,T
        nt.assert_array_almost_equal(u.R, np.eye(3))

        nt.assert_array_almost_equal(UnitQuaternion(rotx(pi / 2)).R, rotx(pi / 2))
        nt.assert_array_almost_equal(UnitQuaternion(roty(-pi / 2)).R, roty(-pi / 2))
        nt.assert_array_almost_equal(UnitQuaternion(rotz(pi)).R, rotz(pi))

        qcompare(UnitQuaternion(rotx(pi / 2)).SO3(), SO3.Rx(pi / 2))
        qcompare(UnitQuaternion(roty(-pi / 2)).SO3(), SO3.Ry(-pi / 2))
        qcompare(UnitQuaternion(rotz(pi)).SO3(), SO3.Rz(pi))

        qcompare(UnitQuaternion(rotx(pi / 2)).SE3(), SE3.Rx(pi / 2))
        qcompare(UnitQuaternion(roty(-pi / 2)).SE3(), SE3.Ry(-pi / 2))
        qcompare(UnitQuaternion(rotz(pi)).SE3(), SE3.Rz(pi))


    def test_staticconstructors(self):
        # rotation primitives
        for theta in [-pi / 2, 0, pi / 2, pi]:
            nt.assert_array_almost_equal(UnitQuaternion.Rx(theta).R, rotx(theta))

        for theta in [-pi / 2, 0, pi / 2, pi]:
            nt.assert_array_almost_equal(UnitQuaternion.Ry(theta).R, roty(theta))

        for theta in [-pi / 2, 0, pi / 2, pi]:
            nt.assert_array_almost_equal(UnitQuaternion.Rz(theta).R, rotz(theta))

        for theta in np.r_[-pi / 2, 0, pi / 2, pi] * 180 / pi:
            nt.assert_array_almost_equal(UnitQuaternion.Rx(theta, 'deg').R, rotx(theta, 'deg'))

        for theta in [-pi / 2, 0, pi / 2, pi]:
            nt.assert_array_almost_equal(UnitQuaternion.Ry(theta, 'deg').R, roty(theta, 'deg'))

        for theta in [-pi / 2, 0, pi / 2, pi]:
            nt.assert_array_almost_equal(UnitQuaternion.Rz(theta, 'deg').R, rotz(theta, 'deg'))

        # 3 angle
        nt.assert_array_almost_equal(UnitQuaternion.RPY([0.1, 0.2, 0.3]).R, rpy2r(0.1, 0.2, 0.3))

        nt.assert_array_almost_equal(UnitQuaternion.Eul([0.1, 0.2, 0.3]).R, eul2r(0.1, 0.2, 0.3))

        nt.assert_array_almost_equal(UnitQuaternion.RPY([10, 20, 30], unit='deg').R, rpy2r(10, 20, 30, unit='deg'))

        nt.assert_array_almost_equal(UnitQuaternion.Eul([10, 20, 30], unit='deg').R, eul2r(10, 20, 30, unit='deg'))

        # (theta, v)
        th = 0.2
        v = unitvec([1, 2, 3])
        nt.assert_array_almost_equal(UnitQuaternion.AngVec(th, v).R, angvec2r(th, v))
        nt.assert_array_almost_equal(UnitQuaternion.AngVec(-th, v).R, angvec2r(-th, v))
        nt.assert_array_almost_equal(UnitQuaternion.AngVec(-th, -v).R, angvec2r(-th, -v))
        nt.assert_array_almost_equal(UnitQuaternion.AngVec(th, -v).R, angvec2r(th, -v))

        # (theta, v)
        th = 0.2
        v = unitvec([1, 2, 3])
        nt.assert_array_almost_equal(UnitQuaternion.EulerVec(th * v).R, angvec2r(th, v))
        nt.assert_array_almost_equal(UnitQuaternion.EulerVec(-th * v).R, angvec2r(-th, v))

    def test_canonic(self):
        R = rotx(0)
        qcompare(UnitQuaternion(R), [1, 0, 0, 0])

        R = rotx(pi / 2)
        qcompare(UnitQuaternion(R), np.r_[cos(pi / 4), sin(pi / 4) * np.r_[1, 0, 0]])
        R = roty(pi / 2)
        qcompare(UnitQuaternion(R), np.r_[cos(pi / 4), sin(pi / 4) * np.r_[0, 1, 0]])
        R = rotz(pi / 2)
        qcompare(UnitQuaternion(R), np.r_[cos(pi / 4), sin(pi / 4) * np.r_[0, 0, 1]])

        R = rotx(-pi / 2)
        qcompare(UnitQuaternion(R), np.r_[cos(pi / 4), sin(pi / 4) * np.r_[-1, 0, 0]])
        R = roty(-pi / 2)
        qcompare(UnitQuaternion(R), np.r_[cos(pi / 4), sin(pi / 4) * np.r_[0, -1, 0]])
        R = rotz(-pi / 2)
        qcompare(UnitQuaternion(R), np.r_[cos(pi / 4), sin(pi / 4) * np.r_[0, 0, -1]])

        R = rotx(pi)
        qcompare(UnitQuaternion(R), np.r_[cos(pi / 2), sin(pi / 2) * np.r_[1, 0, 0]])
        R = roty(pi)
        qcompare(UnitQuaternion(R), np.r_[cos(pi / 2), sin(pi / 2) * np.r_[0, 1, 0]])
        R = rotz(pi)
        qcompare(UnitQuaternion(R), np.r_[cos(pi / 2), sin(pi / 2) * np.r_[0, 0, 1]])

        R = rotx(-pi)
        qcompare(UnitQuaternion(R), np.r_[cos(-pi / 2), sin(-pi / 2) * np.r_[1, 0, 0]])
        R = roty(-pi)
        qcompare(UnitQuaternion(R), np.r_[cos(-pi / 2), sin(-pi / 2) * np.r_[0, 1, 0]])
        R = rotz(-pi)
        qcompare(UnitQuaternion(R), np.r_[cos(-pi / 2), sin(-pi / 2) * np.r_[0, 0, 1]])

    def test_convert(self):
        # test conversion from rotn matrix to u.quaternion and back
        R = rotx(0)
        qcompare(UnitQuaternion(R).R, R)

        R = rotx(pi / 2)
        qcompare(UnitQuaternion(R).R, R)
        R = roty(pi / 2)
        qcompare(UnitQuaternion(R).R, R)
        R = rotz(pi / 2)
        qcompare(UnitQuaternion(R).R, R)

        R = rotx(-pi / 2)
        qcompare(UnitQuaternion(R).R, R)
        R = roty(-pi / 2)
        qcompare(UnitQuaternion(R).R, R)
        R = rotz(-pi / 2)
        qcompare(UnitQuaternion(R).R, R)

        R = rotx(pi)
        qcompare(UnitQuaternion(R).R, R)
        R = roty(pi)
        qcompare(UnitQuaternion(R).R, R)
        R = rotz(pi)
        qcompare(UnitQuaternion(R).R, R)

        R = rotx(-pi)
        qcompare(UnitQuaternion(R).R, R)
        R = roty(-pi)
        qcompare(UnitQuaternion(R).R, R)
        R = rotz(-pi)
        qcompare(UnitQuaternion(R).R, R)

    def test_resulttype(self):

        q = Quaternion([2, 0, 0, 0])
        u = UnitQuaternion()

        self.assertIsInstance(q * q, Quaternion)
        self.assertIsInstance(q * u, Quaternion)
        self.assertIsInstance(u * q, Quaternion)
        self.assertIsInstance(u * u, UnitQuaternion)

        # self.assertIsInstance(u.*u, UnitQuaternion)
        # other combos all fail, test this?

        self.assertIsInstance(u / u, UnitQuaternion)

        self.assertIsInstance(u.conj(), UnitQuaternion)
        self.assertIsInstance(u.inv(), UnitQuaternion)
        self.assertIsInstance(u.unit(), UnitQuaternion)
        self.assertIsInstance(q.unit(), UnitQuaternion)

        self.assertIsInstance(q.conj(), Quaternion)

        self.assertIsInstance(q + q, Quaternion)
        self.assertIsInstance(q - q, Quaternion)

        self.assertIsInstance(u + u, Quaternion)
        self.assertIsInstance(u - u, Quaternion)

        # self.assertIsInstance(q+u, Quaternion)
        # self.assertIsInstance(u+q, Quaternion)

        # self.assertIsInstance(q-u, Quaternion)
        # self.assertIsInstance(u-q, Quaternion)
        # TODO test for ValueError in these cases

        self.assertIsInstance(u.SO3(), SO3)
        self.assertIsInstance(u.SE3(), SE3)

    def test_multiply(self):

        vx = np.r_[1, 0, 0]
        vy = np.r_[0, 1, 0]
        vz = np.r_[0, 0, 1]
        rx = UnitQuaternion.Rx(pi / 2)
        ry = UnitQuaternion.Ry(pi / 2)
        rz = UnitQuaternion.Rz(pi / 2)
        u = UnitQuaternion()

        # quat-quat product
        # scalar x scalar

        qcompare(rx * u, rx)
        qcompare(u * rx, rx)

        # vector x vector
        qcompare(UnitQuaternion([ry, rz, rx]) * UnitQuaternion([rx, ry, rz]), UnitQuaternion([ry * rx, rz * ry, rx * rz]))

        # scalar x vector
        qcompare(ry * UnitQuaternion([rx, ry, rz]), UnitQuaternion([ry * rx, ry * ry, ry * rz]))

        # vector x scalar
        qcompare(UnitQuaternion([rx, ry, rz]) * ry, UnitQuaternion([rx * ry, ry * ry, rz * ry]))

        # quatvector product
        # scalar x scalar

        qcompare(rx * vy, vz)

        # scalar x vector
        nt.assert_array_almost_equal(ry * np.c_[vx, vy, vz], np.c_[-vz, vy, vx])

        # vector x scalar
        nt.assert_array_almost_equal(UnitQuaternion([ry, rz, rx]) * vy, np.c_[vy, -vx, vz])

    # def multiply_test_normalized(self):

    #     vx = [1, 0, 0]; vy = [0, 1, 0]; vz = [0, 0, 1]
    #     rx = UnitQuaternion.Rx(pi/2)
    #     ry = UnitQuaternion.Ry(pi/2)
    #     rz = UnitQuaternion.Rz(pi/2)
    #     u = UnitQuaternion()

    #     # quat-quat product
    #     # scalar x scalar

    #     nt.assert_array_almost_equal(double(rx.*u), double(rx))
    #     nt.assert_array_almost_equal(double(u.*rx), double(rx))

    #     # shouldn't make that much difference here
    #     nt.assert_array_almost_equal(double(rx.*ry), double(rx*ry))
    #     nt.assert_array_almost_equal(double(rx.*rz), double(rx*rz))

    #     #vector x vector
    #     #nt.assert_array_almost_equal([ry, rz, rx] .* [rx, ry, rz], [ry.*rx, rz.*ry, rx.*rz])

    #     # scalar x vector
    #     #nt.assert_array_almost_equal(ry .* [rx, ry, rz], [ry.*rx, ry.*ry, ry.*rz])

    #     #vector x scalar
    #     #nt.assert_array_almost_equal([rx, ry, rz] .* ry, [rx.*ry, ry.*ry, rz.*ry])

    def test_divide(self):

        rx = UnitQuaternion.Rx(pi / 2)
        ry = UnitQuaternion.Ry(pi / 2)
        rz = UnitQuaternion.Rz(pi / 2)
        u = UnitQuaternion()

        # scalar / scalar
        # implicity tests inv

        qcompare(rx / u, rx)
        qcompare(ry / ry, u)

        #vector /vector
        qcompare(UnitQuaternion([ry, rz, rx]) / UnitQuaternion([rx, ry, rz]), UnitQuaternion([ry / rx, rz / ry, rx / rz]))

        #vector / scalar
        qcompare(UnitQuaternion([rx, ry, rz]) / ry, UnitQuaternion([rx / ry, ry / ry, rz / ry]))

        # scalar /vector
        qcompare(ry / UnitQuaternion([rx, ry, rz]), UnitQuaternion([ry / rx, ry / ry, ry / rz]))

    def test_angle(self):
            # angle between quaternions
        # pure
        v = [5, 6, 7]

    def test_conversions(self):

        # , 3 angle
        qcompare(UnitQuaternion.RPY([0.1, 0.2, 0.3]).rpy(), [0.1, 0.2, 0.3])

        qcompare(UnitQuaternion.Eul([0.1, 0.2, 0.3]).eul(), [0.1, 0.2, 0.3])

        qcompare(UnitQuaternion.RPY([10, 20, 30], unit='deg').R, rpy2r(10, 20, 30, unit='deg'))

        qcompare(UnitQuaternion.Eul([10, 20, 30], unit='deg').R, eul2r(10, 20, 30, unit='deg'))

        # (theta, v)
        th = 0.2
        v = unitvec([1, 2, 3])
        [a, b] = UnitQuaternion.AngVec(th, v).angvec()
        self.assertAlmostEqual(a, th)
        nt.assert_array_almost_equal(b, v)

        [a, b] = UnitQuaternion.AngVec(-th, v).angvec()
        self.assertAlmostEqual(a, th)
        nt.assert_array_almost_equal(b, -v)

        # null rotation case
        th = 0
        v = unitvec([1, 2, 3])
        [a, b] = UnitQuaternion.AngVec(th, v).angvec()
        self.assertAlmostEqual(a, th)

    #  SO3                     convert to SO3 class
    #  SE3                     convert to SE3 class

    def test_miscellany(self):

        # AbsTol not used since Quaternion supports eq() operator

        rx = UnitQuaternion.Rx(pi / 2)
        ry = UnitQuaternion.Ry(pi / 2)
        rz = UnitQuaternion.Rz(pi / 2)
        u = UnitQuaternion()

        # norm
        qcompare(rx.norm(), 1)
        qcompare(UnitQuaternion([rx, ry, rz]).norm(), [1, 1, 1])

        # unit
        qcompare(rx.unit(), rx)
        qcompare(UnitQuaternion([rx, ry, rz]).unit(), UnitQuaternion([rx, ry, rz]))

        # inner
        nt.assert_array_almost_equal(u.inner(u), 1)
        nt.assert_array_almost_equal(rx.inner(ry), 0.5)
        nt.assert_array_almost_equal(rz.inner(rz), 1)

        q = rx * ry * rz

        qcompare(q**0, u)
        qcompare(q**(-1), q.inv())
        qcompare(q**2, q * q)

        # angle
        # self.assertEqual(angle(u, u), 0)
        # self.assertEqual(angle(u, rx), pi/4)
        # self.assertEqual(angle(u, [rx, u]), pi/4*np.r_[1, 0])
        # self.assertEqual(angle([rx, u], u), pi/4*np.r_[1, 0])
        # self.assertEqual(angle([rx, u], [u, rx]), pi/4*np.r_[1, 1])
        # TODO angle

        # increment
        # w = [0.02, 0.03, 0.04]

        # nt.assert_array_almost_equal(rx.increment(w), rx*UnitQuaternion.omega(w))

    def test_interp(self):

        rx = UnitQuaternion.Rx(pi / 2)
        ry = UnitQuaternion.Ry(pi / 2)
        rz = UnitQuaternion.Rz(pi / 2)
        u = UnitQuaternion()

        q = rx * ry * rz

        # from null
        qcompare(q.interp(0), u)
        qcompare(q.interp(1), q)

        #self.assertEqual(length(q.interp(linspace(0,1, 10))), 10)
        #self.assertTrue(all( q.interp([0, 1]) == [u, q]))
        # TODO vectorizing

        q0_5 = q.interp(0.5)
        qcompare(q0_5 * q0_5, q)

        # between two quaternions
        qcompare(q.interp(0, dest=rx), q)
        qcompare(q.interp(1, dest=rx), rx)

        #self.assertTrue(all( q.interp([0, 1], dest=rx, ) == [q, rx]))

        # test shortest option
        # q1 = UnitQuaternion.Rx(0.9*pi)
        # q2 = UnitQuaternion.Rx(-0.9*pi)
        # qq = q1.interp(q2, 11)
        # qcompare( qq(6), UnitQuaternion.Rx(0) )
        # qq = q1.interp(q2, 11, 'shortest')
        # qcompare( qq(6), UnitQuaternion.Rx(pi) )
        # TODO interp

    def test_eq(self):
        q1 = UnitQuaternion([0, 1, 0, 0])
        q2 = UnitQuaternion([0, -1, 0, 0])
        q3 = UnitQuaternion.Rz(pi / 2)

        self.assertTrue(q1 == q1)
        self.assertTrue(q2 == q2)
        self.assertTrue(q3 == q3)
        self.assertTrue(q1 == q2)  # because of double wrapping
        self.assertFalse(q1 == q3)

        nt.assert_array_almost_equal(UnitQuaternion([q1, q1, q1]) == UnitQuaternion([q1, q1, q1]), [True, True, True])
        nt.assert_array_almost_equal(UnitQuaternion([q1, q2, q3]) == UnitQuaternion([q1, q2, q3]), [True, True, True])
        nt.assert_array_almost_equal(UnitQuaternion([q1, q1, q3]) == q1, [True, True, False])
        nt.assert_array_almost_equal(q3 == UnitQuaternion([q1, q1, q3]), [False, False, True])

    def test_logical(self):
        rx = UnitQuaternion.Rx(pi / 2)
        ry = UnitQuaternion.Ry(pi / 2)

        # equality tests
        self.assertTrue(rx == rx)
        self.assertFalse(rx != rx)
        self.assertFalse(rx == ry)

    def test_dot(self):
        q = UnitQuaternion()
        omega = np.r_[1, 2, 3]

        nt.assert_array_almost_equal(q.dot(omega), np.r_[0, omega / 2])
        nt.assert_array_almost_equal(q.dotb(omega), np.r_[0, omega / 2])

        q = UnitQuaternion.Rx(pi / 2)
        qcompare(q.dot(omega), 0.5 * Quaternion.Pure(omega) * q)
        qcompare(q.dotb(omega), 0.5 * q * Quaternion.Pure(omega))

    def test_matrix(self):

        q1 = UnitQuaternion.RPY([0.1, 0.2, 0.3])
        q2 = UnitQuaternion.RPY([0.2, 0.3, 0.4])

        qcompare(q1 * q2, q1.matrix @ q2.vec)

    def test_vec3(self):

        q1 = UnitQuaternion.RPY([0.1, 0.2, 0.3])
        q2 = UnitQuaternion.RPY([0.2, 0.3, 0.4])

        q12 = q1 * q2

        q1v = q1.vec3
        q2v = q2.vec3

        q12v = UnitQuaternion.qvmul(q1v, q2v)

        q12_ = UnitQuaternion.Vec3(q12v)

        qcompare(q12, q12_)

    # def test_display(self):
    #     ry = UnitQuaternion.Ry(pi/2)

    #     ry.plot()
    #     h = ry.plot()
    #     ry.animate()
    #     ry.animate('rgb')
    #     ry.animate( UnitQuaternion.Rx(pi/2), 'rgb' )


class TestQuaternion(unittest.TestCase):

    def test_constructor(self):

        q = Quaternion()
        self.assertEqual(len(q), 1)
        self.assertIsInstance(q, Quaternion)

        nt.assert_array_almost_equal(Quaternion().vec, [0, 0, 0, 0])

        # from S
        nt.assert_array_almost_equal(Quaternion([1, 0, 0, 0]).vec, [1, 0, 0, 0])
        nt.assert_array_almost_equal(Quaternion([0, 1, 0, 0]).vec, [0, 1, 0, 0])
        nt.assert_array_almost_equal(Quaternion([0, 0, 1, 0]).vec, [0, 0, 1, 0])
        nt.assert_array_almost_equal(Quaternion([0, 0, 0, 1]).vec, [0, 0, 0, 1])

        nt.assert_array_almost_equal(Quaternion([2, 0, 0, 0]).vec, [2, 0, 0, 0])
        nt.assert_array_almost_equal(Quaternion([-2, 0, 0, 0]).vec, [-2, 0, 0, 0])

        # from [S,V]
        nt.assert_array_almost_equal(Quaternion(1, [0, 0, 0]).vec, [1, 0, 0, 0])
        nt.assert_array_almost_equal(Quaternion(0, [1, 0, 0]).vec, [0, 1, 0, 0])
        nt.assert_array_almost_equal(Quaternion(0, [0, 1, 0]).vec, [0, 0, 1, 0])
        nt.assert_array_almost_equal(Quaternion(0, [0, 0, 1]).vec, [0, 0, 0, 1])

        nt.assert_array_almost_equal(Quaternion(2, [0, 0, 0]).vec, [2, 0, 0, 0])
        nt.assert_array_almost_equal(Quaternion(-2, [0, 0, 0]).vec, [-2, 0, 0, 0])

        # pure
        v = [5, 6, 7]
        nt.assert_array_almost_equal(Quaternion.Pure(v).vec, [0, ] + v)

        # tc.verifyError( @() Quaternion.pure([1, 2]), 'SMTB:Quaternion:badarg')

        # copy constructor
        q = Quaternion([1, 2, 3, 4])
        nt.assert_array_almost_equal(Quaternion(q).vec, q.vec)

        # errors

        # tc.verifyError( @() Quaternion(2), 'SMTB:Quaternion:badarg')
        # tc.verifyError( @() Quaternion([1, 2, 3]), 'SMTB:Quaternion:badarg')

    def test_string(self):

        u = Quaternion()

        s = str(u)
        self.assertIsInstance(s, str)
        self.assertTrue(s.endswith(' >'))
        self.assertEqual(s.count('\n'), 0)
        self.assertEqual(len(s), 37)

        q = Quaternion([u, u, u])
        s = str(q)
        self.assertIsInstance(s, str)
        self.assertEqual(s.count('\n'), 2)

    def test_properties(self):

        q = Quaternion([1, 2, 3, 4])
        self.assertEqual(q.s, 1)
        nt.assert_array_almost_equal(q.v, np.r_[2, 3, 4])
        nt.assert_array_almost_equal(q.vec, np.r_[1, 2, 3, 4])

    def log_test_exp(self):

        q1 = Quaternion([4, 3, 2, 1])
        q2 = Quaternion([-1, 2, -3, 4])

        nt.assert_array_almost_equal(exp(log(q1)), q1)
        nt.assert_array_almost_equal(exp(log(q2)), q2)

        #nt.assert_array_almost_equal(log(exp(q1)), q1)
        #nt.assert_array_almost_equal(log(exp(q2)), q2)



    def test_concat(self):
        u = Quaternion()
        uu = Quaternion([u, u, u, u])

        self.assertIsInstance(uu, Quaternion)
        self.assertEqual(len(uu), 4)

    def primitive_test_convert(self):

        # s,v
        nt.assert_array_almost_equal(Quaternion([1, 0, 0, 0]).s, 1)
        nt.assert_array_almost_equal(Quaternion([1, 0, 0, 0]).v, [0, 0, 0])

        nt.assert_array_almost_equal(Quaternion([0, 1, 0, 0]).s, 0)
        nt.assert_array_almost_equal(Quaternion([0, 1, 0, 0]).v, [1, 0, 0])

        nt.assert_array_almost_equal(Quaternion([0, 0, 1, 0]).s, 0)
        nt.assert_array_almost_equal(Quaternion([0, 0, 1, 0]).v, [0, 1, 0])

        nt.assert_array_almost_equal(Quaternion([0, 0, 0, 1]).s, 0)
        nt.assert_array_almost_equal(Quaternion([0, 0, 0, 1]).v, [0, 0, 1])

    def test_resulttype(self):

        q = Quaternion([2, 0, 0, 0])

        self.assertIsInstance(q, Quaternion)

        # other combos all fail, test this?

        self.assertIsInstance(q.conj(), Quaternion)
        self.assertIsInstance(q.unit(), UnitQuaternion)

        self.assertIsInstance(q + q, Quaternion)
        self.assertIsInstance(q + q, Quaternion)

    def test_multiply(self):

        q1 = Quaternion([1, 2, 3, 4])
        q2 = Quaternion([4, 3, 2, 1])
        q3 = Quaternion([-1, 2, -3, 4])

        u = Quaternion([1, 0, 0, 0])

        # quat-quat product
        # scalar x scalar

        qcompare(q1 * u, q1)
        qcompare(u * q1, q1)
        qcompare(q1 * q2, [-12, 6, 24, 12])

        q = q1
        q *= q2
        qcompare(q, [-12, 6, 24, 12])

        # vector x vector
        qcompare(Quaternion([q1, u, q2, u, q3, u]) * Quaternion([u, q1, u, q2, u, q3]), Quaternion([q1, q1, q2, q2, q3, q3]))

        q = Quaternion([q1, u, q2, u, q3, u])
        q *= Quaternion([u, q1, u, q2, u, q3])
        qcompare(q, Quaternion([q1, q1, q2, q2, q3, q3]))

        # scalar x vector
        qcompare(q1 * Quaternion([q1, q2, q3]), Quaternion([q1 * q1, q1 * q2, q1 * q3]))

        # vector x scalar
        qcompare(Quaternion([q1, q2, q3]) * q2, Quaternion([q1 * q2, q2 * q2, q3 * q2]))

        # quat-real product
        # scalar x scalar

        v1 = q1.vec
        qcompare(q1 * 5, v1 * 5)
        qcompare(6 * q1, v1 * 6)
        qcompare(-2 * q1, -2 * v1)

        # scalar x vector
        qcompare(5 * Quaternion([q1, q2, q3]), Quaternion([5 * q1, 5 * q2, 5 * q3]))

        # vector x scalar
        qcompare(Quaternion([q1, q2, q3]) * 5, Quaternion([5 * q1, 5 * q2, 5 * q3]))

        # matrix form of multiplication
        qcompare(q1.matrix @ q2.vec, q1 * q2)

        # quat-scalar product
        qcompare(q1 * 2, q1.vec * 2)
        qcompare(Quaternion([q1 * 2, q2 * 2]), Quaternion([q1, q2]) * 2)

        # errors

        # tc.verifyError( @() q1 * [1, 2, 3], 'SMTB:Quaternion:badarg')
        # tc.verifyError( @() [1, 2, 3]*q1, 'SMTB:Quaternion:badarg')
        # tc.verifyError( @() [q1, q1] * [q1, q1, q1], 'SMTB:Quaternion:badarg')
        # tc.verifyError( @() q1*SE3, 'SMTB:Quaternion:badarg')

    def test_equality(self):
        q1 = Quaternion([1, 2, 3, 4])
        q2 = Quaternion([-2, 1, -4, 3])

        self.assertTrue(q1 == q1)
        self.assertFalse(q1 == q2)

        self.assertTrue(q1 != q2)
        self.assertFalse(q2 != q2)

        qt1 = Quaternion([q1, q1, q2, q2])
        qt2 = Quaternion([q1, q2, q2, q1])

        self.assertEqual(qt1 == q1, [True, True, False, False])
        self.assertEqual(q1 == qt1, [True, True, False, False])
        self.assertEqual(qt1 == qt1, [True, True, True, True])

        self.assertEqual(qt2 == q1, [True, False, False, True])
        self.assertEqual(q1 == qt2, [True, False, False, True])
        self.assertEqual(qt1 == qt2, [True, False, True, False])

        self.assertEqual(qt1 != q1, [False, False, True, True])
        self.assertEqual(q1 != qt1, [False, False, True, True])
        self.assertEqual(qt1 != qt1, [False, False, False, False])

        self.assertEqual(qt2 != q1, [False, True, True, False])
        self.assertEqual(q1 != qt2, [False, True, True, False])
        self.assertEqual(qt1 != qt2, [False, True, False, True])

        # errors

        # tc.verifyError( @() [q1 q1] == [q1 q1 q1], 'SMTB:Quaternion:badarg')
        # tc.verifyError( @() [q1 q1] != [q1 q1 q1], 'SMTB:Quaternion:badarg')

    def basic_test_multiply(self):
        # test run multiplication tests on quaternions
        q = Quaternion([1, 0, 0, 0]) * Quaternion([1, 0, 0, 0])
        qcompare(q.vec, [1, 0, 0, 0])

        q = Quaternion([1, 0, 0, 0]) * Quaternion([1, 2, 3, 4])
        qcompare(q.vec, [1, 2, 3, 4])

        q = Quaternion([1, 2, 3, 4]) * Quaternion([1, 2, 3, 4])
        qcompare(q.vec, [-28, 4, 6, 8])

    def add_test_sub(self):
        v1 = [1, 2, 3, 4]
        v2 = [2, 2, 4, 7]

        # plus
        q = Quaternion(v1) + Quaternion(v2)
        q2 = Quaternion(v1) + v2

        qcompare(q.vec, v1 + v2)
        qcompare(q2.vec, v1 + v2)

        # minus
        q = Quaternion(v1) - Quaternion(v2)
        q2 = Quaternion(v1) - v2
        qcompare(q.vec, v1 - v2)
        qcompare(q2.vec, v1 - v2)

    def test_power(self):

        q = Quaternion([1, 2, 3, 4])

        qcompare(q**0, Quaternion([1, 0, 0, 0]))
        qcompare(q**1, q)
        qcompare(q**2, q * q)

    def test_miscellany(self):
        v = np.r_[1, 2, 3, 4]
        q = Quaternion(v)
        u = Quaternion([1, 0, 0, 0])

        # norm
        nt.assert_array_almost_equal(q.norm(), np.linalg.norm(v))
        nt.assert_array_almost_equal(Quaternion([q, u, q]).norm(), [np.linalg.norm(v), 1, np.linalg.norm(v)])

        # unit
        qu = q.unit()
        uu = UnitQuaternion()
        self.assertIsInstance(q, Quaternion)
        nt.assert_array_almost_equal(qu.vec, v / np.linalg.norm(v))
        qcompare(Quaternion([q, u, q]).unit(), UnitQuaternion([qu, uu, qu]))

        # inner
        nt.assert_equal(u.inner(u), 1)
        nt.assert_equal(q.inner(q), q.norm()**2)
        nt.assert_equal(q.inner(u), np.dot(q.vec, u.vec))


# ---------------------------------------------------------------------------------------#
if __name__ == '__main__':

    unittest.main()
