import numpy as np
from numpy.testing import assert_raises, assert_almost_equal
from numpy import sqrt, ceil

from skimage import data
from skimage import img_as_float
from skimage.feature import daisy


def test_daisy_color_image_unsupported_error():
    img = np.zeros((20, 20, 3))
    assert_raises(ValueError, daisy, img)


def test_daisy_desc_dims():
    img = img_as_float(data.lena()[:128, :128].mean(axis=2))
    rings = 2
    histograms = 4
    orientations = 3
    descs = daisy(img, rings=rings, histograms=histograms, orientations=orientations)
    assert(descs.shape[2] == (rings*histograms + 1)*orientations)

    rings = 4
    histograms = 5
    orientations = 13
    descs = daisy(img, rings=rings, histograms=histograms, orientations=orientations)
    assert(descs.shape[2] == (rings*histograms + 1)*orientations)


def test_descs_shape():
    img = img_as_float(data.lena()[:256, :256].mean(axis=2))
    radius = 20
    step = 8
    descs = daisy(img, radius=radius, step=step)
    assert(descs.shape[0] == ceil((img.shape[0]-radius*2)/float(step)))
    assert(descs.shape[1] == ceil((img.shape[1]-radius*2)/float(step)))

    img = img[:-1,:-2]
    radius = 5
    step = 3
    descs = daisy(img, radius=radius, step=step)
    assert(descs.shape[0] == ceil((img.shape[0]-radius*2)/float(step)))
    assert(descs.shape[1] == ceil((img.shape[1]-radius*2)/float(step)))


def test_daisy_incompatible_sigmas_and_radii():
    img = img_as_float(data.lena()[:128, :128].mean(axis=2))
    sigmas = [1, 2]
    radii = [1, 2]
    assert_raises(ValueError, daisy, img, sigmas=sigmas, ring_radii=radii)


def test_daisy_normalization():
    img = img_as_float(data.lena()[:64, :64].mean(axis=2))

    descs = daisy(img, normalization='l1')
    for i in range(descs.shape[0]):
        for j in range(descs.shape[1]):
            assert_almost_equal(np.sum(descs[i,j,:]), 1)
    descs_ = daisy(img)
    assert_almost_equal(descs, descs_)

    descs = daisy(img, normalization='l2')
    for i in range(descs.shape[0]):
        for j in range(descs.shape[1]):
            assert_almost_equal(sqrt(np.sum(descs[i,j,:]**2)), 1)

    orientations = 8
    descs = daisy(img, orientations=orientations, normalization='daisy')
    desc_dims = descs.shape[2]
    for i in range(descs.shape[0]):
        for j in range(descs.shape[1]):
            for k in range(0, desc_dims, orientations):
                assert_almost_equal(sqrt(np.sum(
                        descs[i,j,k:k+orientations]**2)), 1)

    img = np.zeros((50, 50))
    descs = daisy(img, normalization='off')
    for i in range(descs.shape[0]):
        for j in range(descs.shape[1]):
            assert_almost_equal(np.sum(descs[i,j,:]), 0)

    assert_raises(ValueError, daisy, img, normalization='does_not_exist')


if __name__ == '__main__':
    from numpy import testing
    testing.run_module_suite()