# ============================================
# Multi-stage build for production backend
# ============================================

# Stage 1: Build dependencies
FROM python:3.11-slim AS builder

ARG PYTHON_VERSION=3.11

WORKDIR /app

# Install system dependencies
RUN apt-get update && apt-get install -y \
    gcc \
    g++ \
    libsndfile1 \
    ffmpeg \
    && rm -rf /var/lib/apt/lists/*

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

# Stage 2: Production runtime
FROM python:3.11-slim AS production

WORKDIR /app

# Install runtime dependencies only
RUN apt-get update && apt-get install -y \
    libsndfile1 \
    ffmpeg \
    curl \
    && rm -rf /var/lib/apt/lists/*

# Copy Python dependencies from builder
COPY --from=builder /root/.local /root/.local

# Make sure scripts in .local are usable
ENV PATH=/root/.local/bin:$PATH

# Copy application code
COPY . .

# Create non-root user
RUN useradd -m -u 1000 appuser && \
    chown -R appuser:appuser /app

# Switch to non-root user
USER appuser

# Expose port
EXPOSE 8000

# Health check
HEALTHCHECK --interval=30s --timeout=3s --start-period=10s --retries=3 \
  CMD curl -f http://localhost:8000/health || exit 1

# Run application with gunicorn
CMD ["gunicorn", "app.main:app", \
     "--workers", "4", \
     "--worker-class", "uvicorn.workers.UvicornWorker", \
     "--bind", "0.0.0.0:8000", \
     "--timeout", "120", \
     "--keep-alive", "5", \
     "--access-logfile", "-", \
     "--error-logfile", "-", \
     "--log-level", "info"]