FROM python:3.12-slim

# Prevent Python from writing .pyc files and enable unbuffered logs.
ENV PYTHONDONTWRITEBYTECODE=1
ENV PYTHONUNBUFFERED=1

WORKDIR /app

# Install dependencies first for better layer caching.
COPY requirements.txt ./
RUN pip install --no-cache-dir -r requirements.txt

COPY . .

EXPOSE 5000

# Keep testing and local dev via `flask` if desired; docker runs the app directly.
CMD ["python", "app.py"]