#!/usr/bin/env python3
"""Test-Helfer: PNG <-> rohes RGB-Byte-Array (nur für den Interop-Test)."""
import os
import sys
from PIL import Image

if sys.argv[1] == "mkcarrier":     # mkcarrier <out.png> <W> <H>  -> Rausch-Trägerbild
    w, h = int(sys.argv[3]), int(sys.argv[4])
    img = Image.frombytes("RGB", (w, h), os.urandom(w * h * 3))
    img.save(sys.argv[2], "PNG")
    print("ok")
elif sys.argv[1] == "png2rgb":     # png2rgb <in.png> <out.bin>  -> stdout: "W H"
    img = Image.open(sys.argv[2]).convert("RGB")
    w, h = img.size
    with open(sys.argv[3], "wb") as fh:
        fh.write(bytes([v for px in img.getdata() for v in px]))
    print(w, h)
elif sys.argv[1] == "rgb2png":     # rgb2png <in.bin> <W> <H> <out.png>
    w, h = int(sys.argv[3]), int(sys.argv[4])
    data = open(sys.argv[2], "rb").read()
    img = Image.new("RGB", (w, h))
    img.putdata([tuple(data[i:i + 3]) for i in range(0, len(data), 3)])
    img.save(sys.argv[5], "PNG")
    print("ok")