"""Prepare Android screenshots for model input without changing device coordinates."""

from io import BytesIO

from PIL import Image


def limit_screenshot_long_edge(image_bytes: bytes, max_long_edge: int) -> bytes:
    """Downscale oversized screenshots; keep smaller images byte-for-byte unchanged."""
    try:
        with Image.open(BytesIO(image_bytes)) as image:
            long_edge = max(image.size)
            if long_edge <= max_long_edge:
                return image_bytes
            scale = max_long_edge / long_edge
            size = tuple(max(1, round(side * scale)) for side in image.size)
            resized = image.convert("RGB").resize(size, Image.Resampling.LANCZOS)
            output = BytesIO()
            resized.save(output, format="JPEG", quality=80, optimize=True)
            return output.getvalue()
    except OSError:
        # Preserve the capture path's previous behavior for invalid placeholder images.
        return image_bytes