FROM python:3.11-slim

ENV PYTHONDONTWRITEBYTECODE=1 \
    PYTHONUNBUFFERED=1 \
    PIP_NO_CACHE_DIR=1

WORKDIR /app

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

# Copy application code and runtime artifacts.
COPY api ./api
COPY src ./src
COPY configs ./configs
COPY models ./models
COPY artifacts ./artifacts

# Run API as non-root user.
RUN useradd --create-home --shell /usr/sbin/nologin appuser \
    && chown -R appuser:appuser /app
USER appuser

EXPOSE 8000

HEALTHCHECK --interval=30s --timeout=5s --start-period=20s --retries=3 \
  CMD python -c "import urllib.request,sys; urllib.request.urlopen('http://127.0.0.1:8000/health'); sys.exit(0)"

CMD ["uvicorn", "api.app:app", "--host", "0.0.0.0", "--port", "8000"]