import numpy as np


def add_mask(image, label, vis_labels, colors, alpha=0.5):

    if len(image.shape) < 3 or image.shape[2] == 1:
        image = image.repeat(3).reshape((image.shape[0], image.shape[1], 3)).astype(np.uint8)
    ori_image = image.copy()

    for ci, vis_label in enumerate(vis_labels):
        color = colors[ci]
        mask = label == vis_label
        for i in range(3):
            image[:, :, i][mask] = (color[i] * alpha + image[:, :, i][mask] * (1 - alpha)).astype(np.uint8)

    return ori_image, image


def find_haight(mask):
    
    v_sum = (np.sum(mask, axis=1) > 0).astype(np.uint8)
    
    v_diff = np.diff(np.hstack((0, v_sum, 0)))
    
    v_min_y = np.where(v_diff > 0)[0][0]
    v_max_y = np.where(v_diff < 0)[0][-1] - 1
    
    return v_max_y - v_min_y


def simple_vcdr(mask):

    disc_mask = (mask > 0).astype(np.uint8)
    disc_height = find_haight(disc_mask)

    cup_mask = (mask > 1).astype(np.uint8)
    cup_height = find_haight(cup_mask)

    vcdr = cup_height / disc_height

    return vcdr