#!/usr/bin/env python3

import os, math, sys
from PIL import Image, ImageFont, ImageDraw

wm_width = 1254
wm_height = 705
brightness_threshold = 125

def determine_brightness(image):
	gray = image.convert('L')
	top_left = ((gray.width - wm_width) // 2, (gray.height - wm_height) // 2)

	total = 0
	for i in range(top_left[0], top_left[0] + wm_width):
		for j in range(top_left[1], top_left[1] + wm_height):
			total += gray.getpixel((i, j))
	brightness = total / (wm_width * wm_height) # This is on a scale of 0-256
	return brightness


def watermark():
	with Image.open("IMG_0035.png") as image:
		if determine_brightness(image) > brightness_threshold:
			black = Image.open("./{}.png".format("black-t")).convert("RGBA")
			logo = black
		else:
			white = Image.open("./{}.png".format("white-t")).convert("RGBA")
			logo = white


		image_w, image_h = image.size

		logo_w, logo_h = logo.size
		offset = ((image_w - logo_w) // 2, (image_h - logo_h) // 2)

		image_copy = image.copy()
		position = ((image_copy.width - logo.width), (image_copy.height - logo.height))

		image_copy.paste(logo, offset, logo)
		image_copy.show()


watermark()