# Multi-stage build for optimized Python application
FROM python:3.11-slim AS builder

# Set build-time environment variables
ENV PYTHONDONTWRITEBYTECODE=1 \
    PYTHONUNBUFFERED=1 \
    PIP_NO_CACHE_DIR=1 \
    PIP_DISABLE_PIP_VERSION_CHECK=1

# Install build dependencies only
RUN apt-get update && apt-get install -y \
    build-essential \
    curl \
    git \
    && rm -rf /var/lib/apt/lists/* && \
    apt-get clean

# Configure SSH to trust GitHub host key
RUN mkdir -p ~/.ssh && \
    ssh-keyscan -t rsa github.com >> ~/.ssh/known_hosts && \
    chmod 600 ~/.ssh/known_hosts

# Create virtual environment
RUN python -m venv /opt/venv
ENV PATH="/opt/venv/bin:$PATH"

# Upgrade pip and wheel for better caching
RUN pip install --upgrade pip setuptools wheel

# Copy requirements files for better Docker layer caching
COPY requirements.txt ./

# Install only production dependencies with no cache
RUN --mount=type=ssh echo "=== Installing dependencies ===" && \
    pip install --no-cache-dir -r requirements.txt && \
    echo "=== Dependencies installed successfully ===" && \
    pip list | wc -l && \
    echo "=== Cleaning cache files ===" && \
    find /opt/venv -type d -name __pycache__ -exec rm -rf {} + 2>/dev/null || true && \
    find /opt/venv -name "*.pyc" -delete 2>/dev/null || true && \
    rm -rf /root/.cache/pip/* && \
    echo "=== Cleaning venv site-packages ===" && \
    find /opt/venv/lib/python3.11/site-packages/ -type f -name "*.md" -delete 2>/dev/null || true && \
    echo "=== Stripping .so files ===" && \
    find /opt/venv -name "*.so" -exec strip {} + 2>/dev/null || true

# Production stage using python-slim for better functionality
FROM python:3.11-slim AS production

# Set environment variables
ENV PYTHONDONTWRITEBYTECODE=1 \
    PYTHONUNBUFFERED=1 \
    PATH="/opt/venv/bin:$PATH" \
    POD_ID=unknown \
    HOME="/app"

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

# Set working directory
WORKDIR /app

# Copy application code
COPY . .

# Create necessary directories for runtime file creation
RUN mkdir -p /app/model_manager/reports /app/logs /app/temp /app/models /app/data && \
    chmod 755 /app/model_manager/reports /app/logs /app/temp /app/models /app/data

# Create non-root user
RUN groupadd -r appuser && useradd -r -g appuser appuser && \
    chown -R appuser:appuser /app

# Switch to non-root user
USER appuser

# Set entrypoint for proper signal handling and PID 1
ENTRYPOINT ["/opt/venv/bin/python", "-m", "model_manager.worker.worker"]
