FROM python:3.11-slim

# Set environment variables
ENV PYTHONDONTWRITEBYTECODE=1
ENV PYTHONUNBUFFERED=1

# Set work directory
WORKDIR /app

# Install system dependencies
RUN apt-get update && apt-get install -y --no-install-recommends \
    gcc \
    libc-dev \
    libffi-dev \
    && rm -rf /var/lib/apt/lists/*

# Install Python dependencies
COPY requirements.txt .
RUN pip install --no-cache-dir -r requirements.txt

# Copy application
COPY . .

# Create upload directory
RUN mkdir -p /tmp/stego_uploads

# Create non-root user for security
RUN useradd -m -u 1000 stego && chown -R stego:stego /app /tmp/stego_uploads
USER stego

# Expose port
EXPOSE 5000

# Health check
HEALTHCHECK --interval=30s --timeout=10s --start-period=5s --retries=3 \
    CMD python -c "import urllib.request; urllib.request.urlopen('http://localhost:5000/')" || exit 1

# Run with gunicorn in production
CMD ["gunicorn", "--bind", "0.0.0.0:5000", "--workers", "2", "--threads", "4", "--timeout", "60", "app:app"]