FROM python:3.10-slim

WORKDIR /app

# copy & install python deps first for layer caching
COPY requirements.txt .
RUN pip install --no-cache-dir -r requirements.txt

# copy app
COPY . .

# ensure app listens on PORT env var (we used 7860 by default)
ENV PORT=7860
EXPOSE 7860

# use gunicorn to serve the Flask app: the module is app:app
CMD ["gunicorn", "-w", "1", "-b", "0.0.0.0:7860", "app:app"]