import base64
import io
import requests
from PIL import Image


def encode_image_base64(pil_image: Image.Image) -> str:
    """Encode a PIL Image to a base64 data URI for DashScope API input."""
    buffer = io.BytesIO()
    fmt = pil_image.format or "JPEG"
    if fmt not in ("JPEG", "PNG"):
        fmt = "JPEG"
    pil_image.save(buffer, format=fmt)
    b64 = base64.b64encode(buffer.getvalue()).decode("utf-8")
    mime = "image/jpeg" if fmt == "JPEG" else "image/png"
    return f"data:{mime};base64,{b64}"


def download_image(url: str) -> Image.Image:
    """Download image from a URL and return as PIL Image."""
    response = requests.get(url, timeout=30)
    response.raise_for_status()
    return Image.open(io.BytesIO(response.content))