#!/usr/bin/env python3

########################################################################
##
##  cap_check.py
##
##  Copyright (C) 2024 Herbert Poetzl
##
##
##  This program is free software; you can redistribute it and/or modify
##  it under the terms of the GNU General Public License version 2 as
##  published by the Free Software Foundation.
##
########################################################################

import sys
import struct

capw = 1920
caph = 1080

fmax = None
if len(sys.argv) > 2:
    fmax = int(sys.argv[2], 0)

def fletcher4(data):
    a = b = c = d = 0

    for val in struct.iter_unpack('I', data):
        a += val[0];
        b += a;
        c += b;
        d += c;

    a &= 0xFFFFFFFF
    b &= 0xFFFFFFFF
    c &= 0xFFFFFFFF
    d &= 0xFFFFFFFF

    return ((a ^ c) << 32) ^ b ^ d

flsd = {}
fcnt = 0
prev = None
with open(sys.argv[1], "rb") as f:
    while True:
        data = f.read(capw*caph*3)
        if len(data) < capw*caph*3:
            break

        if fmax and fcnt >= fmax:
            break

        data = bytearray(data)

        corn = []
        for y in [0, caph-1]:
            for x in [0, capw-1]:
                idx = (x + y*capw)*3
                val = data[idx] 
                val = (val << 8) | data[idx+1]
                val = (val << 8) | data[idx+2]
                corn.append(val)

                data[idx:idx+3] = b"\0\0\0"

        out = False
        fl4 = fletcher4(data)
        fls = f"{fl4:016X}"

        hcor = [f"{_:06X}" for _ in corn]
        print(f"{fcnt:06X}", fls, \
            " ".join(hcor), f"# [{len(data):d}]")

        fcnt += 1

    print(flsd)