# ============================================================================
# Multi-Stage Dockerfile for Recticel Quality Application
# Optimized for production deployment with minimal image size and security
# ============================================================================

# ============================================================================
# Stage 1: Builder - Install dependencies and prepare application
# ============================================================================
FROM python:3.10-slim AS builder

# Prevent Python from writing pyc files and buffering stdout/stderr
ENV PYTHONDONTWRITEBYTECODE=1 \
    PYTHONUNBUFFERED=1 \
    PIP_NO_CACHE_DIR=1 \
    PIP_DISABLE_PIP_VERSION_CHECK=1

# Install build dependencies (will be discarded in final stage)
RUN apt-get update && apt-get install -y --no-install-recommends \
    gcc \
    g++ \
    default-libmysqlclient-dev \
    pkg-config \
    && rm -rf /var/lib/apt/lists/*

# Create and use a non-root user for security
RUN useradd -m -u 1000 appuser

# Set working directory
WORKDIR /app

# Copy and install Python dependencies
# Copy only requirements first to leverage Docker layer caching
COPY py_app/requirements.txt .

# Install Python packages in a virtual environment for better isolation
RUN python -m venv /opt/venv
ENV PATH="/opt/venv/bin:$PATH"
RUN pip install --upgrade pip setuptools wheel && \
    pip install --no-cache-dir -r requirements.txt

# ============================================================================
# Stage 2: Runtime - Minimal production image
# ============================================================================
FROM python:3.10-slim AS runtime

# Set Python environment variables
ENV PYTHONDONTWRITEBYTECODE=1 \
    PYTHONUNBUFFERED=1 \
    FLASK_APP=run.py \
    FLASK_ENV=production \
    PATH="/opt/venv/bin:$PATH"

# Install only runtime dependencies (much smaller than build deps)
RUN apt-get update && apt-get install -y --no-install-recommends \
    default-libmysqlclient-dev \
    mariadb-client \
    curl \
    ca-certificates \
    && rm -rf /var/lib/apt/lists/* \
    && apt-get clean

# Create non-root user for running the application
RUN useradd -m -u 1000 appuser

# Set working directory
WORKDIR /app

# Copy virtual environment from builder stage
COPY --from=builder /opt/venv /opt/venv

# Copy application code
COPY --chown=appuser:appuser py_app/ .

# Copy entrypoint script
COPY --chown=appuser:appuser docker-entrypoint.sh /docker-entrypoint.sh
RUN chmod +x /docker-entrypoint.sh

# Create necessary directories with proper ownership
RUN mkdir -p /app/instance /srv/quality_recticel/logs && \
    chown -R appuser:appuser /app /srv/quality_recticel

# Switch to non-root user for security
USER appuser

# Expose the application port
EXPOSE 8781

# Health check - verify the application is responding
# Disabled by default in Dockerfile, enable in docker-compose if needed
HEALTHCHECK --interval=30s --timeout=10s --start-period=60s --retries=3 \
    CMD curl -f http://localhost:8781/ || exit 1

# Use the entrypoint script for initialization
ENTRYPOINT ["/docker-entrypoint.sh"]

# Default command: run gunicorn with optimized configuration
# Can be overridden in docker-compose.yml or at runtime
CMD ["gunicorn", "--config", "gunicorn.conf.py", "wsgi:application"]

# ============================================================================
# Build arguments for versioning and metadata
# ============================================================================
ARG BUILD_DATE
ARG VERSION
ARG VCS_REF

# Labels for container metadata
LABEL org.opencontainers.image.created="${BUILD_DATE}" \
      org.opencontainers.image.version="${VERSION}" \
      org.opencontainers.image.revision="${VCS_REF}" \
      org.opencontainers.image.title="Recticel Quality Application" \
      org.opencontainers.image.description="Production-ready Docker image for Trasabilitate quality management system" \
      org.opencontainers.image.authors="Quality Team" \
      maintainer="quality-team@recticel.com"