from Cimpl import create_color, create_image, get_color, set_color,\
                  Image

from test_invert import check_equal

from L7_15_P5_horizontal import flip_horizontal

def test_flip_horizontal() -> None:
    '''
    101162929 Hiu Sum Jaime Yue
    A test function for flip_horizontal.

    >>> test_flip_horizontal()
    '''
    # Create an image with eight pixels. For testing the flip horizontal filter,
    # I picked eight random set of RGB colour codes, just to check if the filter
    # is working. For the RGB value of (0,0) should swap with the RGB
    # values in (0,3). The RGB value of (0,1) should swap with the RGB values
    # in (0,2). Check if anything in the code affect the x value, I create one
    # more column. For the RGB value of (1,0) should swap with the RGB
    # values in (1,3). The RGB value of (1,1) should swap with the RGB values
    # in (1,2).

    original = create_image(2, 4)
    set_color(original, 0, 0,  create_color(0, 0, 0))
    set_color(original, 0, 1,  create_color(128, 127, 128))
    set_color(original, 0, 2,  create_color(0, 0, 1))
    set_color(original, 0, 3,  create_color(255, 255, 255))
    set_color(original, 1, 0,  create_color(254, 254, 254))
    set_color(original, 1, 1,  create_color(128, 127, 128))
    set_color(original, 1, 2,  create_color(254, 255, 254))
    set_color(original, 1, 3,  create_color(0, 1, 0))

    # Create an image that's identical to the one a correct implementation of
    # flip_horizontal should produce when it is passed original.

    expected = create_image(2, 4)
    set_color(expected, 0, 0,  create_color(255, 255, 255))
    set_color(expected, 0, 1,  create_color(0, 0, 1))
    set_color(expected, 0, 2,  create_color(128, 127, 128))
    set_color(expected, 0, 3,  create_color(0, 0, 0))
    set_color(expected, 1, 0,  create_color(0, 1, 0))
    set_color(expected, 1, 1,  create_color(254, 255, 254))
    set_color(expected, 1, 2,  create_color(128, 127, 128))
    set_color(expected, 1, 3,  create_color(254, 254, 254))

    # Compare the transformed image returned by the filter with the
    # expected image, one pixel at a time.

    fliped = flip_horizontal(original)
    for x, y, col in fliped:
        check_equal('Checking pixel @(' + str(x) + ', ' + str(y) + ')',
                     col, get_color(expected, x, y))

test_flip_horizontal()