from PIL import Image
import math
import argparse
import os.path

parser = argparse.ArgumentParser(
                    prog = 'Image Edit Script',
                    description = 'Manipulate or extract information from an image file',
                    epilog = '')

parser.add_argument('filename')           # positional argument
parser.add_argument('-n', '--bytesperline')
parser.add_argument('-b', '--lsbfirst', action='store_true')
parser.add_argument('-i', '--invert', action='store_true')

args = parser.parse_args()

lsbfirst=args.lsbfirst
invert=args.invert

bytesperline=16
if args.bytesperline is not None:
    bytesperline=args.bytesperline #for output formatting


im = Image.open(args.filename) # Can be many different formats.
pix = im.load()
print(im.size)  # Get the width and hight of the image for iterating over


array=[] #array with every element a byte

thresh=128 #threshold brightness
    
def calculateDistance(x1,y1,x2,y2):  
    dist = math.sqrt((x2 - x1)**2 + (y2 - y1)**2)  
    return dist  
    
temp_byte=0
temp_byte_pos=0
for y in range(im.size[1]):
    for x in range(im.size[0]):
        c = pix[x,y] #get pixel
        r=c[0]
        g=c[1]
        b=c[2]
        if invert:
            r=255-r
            g=255-g
            b=255-b

        if ((r+g+b)/3 < thresh ): #black
            if lsbfirst:
                temp_byte+=1<<temp_byte_pos
            else:
                temp_byte+=1<<(7-temp_byte_pos)

        temp_byte_pos+=1
        if temp_byte_pos>=8: #finished assemblying byte
            array.append(temp_byte)
            temp_byte_pos=0 #reset
            temp_byte=0

        
if os.path.isfile(args.filename+'.txt'):
    print("Outputfile "+args.filename+".txt exists")
    exit()

with open(args.filename+'.txt', 'w') as f:
    f.write("const unsigned char gImage_4in2[]  = {")
    f.write('\r\n')
    counter=0
    for a in array: #for every byte
        f.write("0X{:02X}".format(a)+',') #Example output: 0XFF,0XFF,0XFF,0XFF,0XFF,0XFF,0XFF,0XFF,0XFF,0XFF,0XFF,0XFF,0XFF,0XFF,0XFF,0XFF,
        counter+=1
        if counter>=bytesperline:
            f.write('\r\n')
            counter=0
    f.write("};")