# Production-grade Dockerfile for TB-Guard-XAI
# Multi-stage build for optimized image size

# ========== Stage 1: Builder ==========
FROM python:3.11-slim as builder

# Install build dependencies
RUN apt-get update && apt-get install -y --no-install-recommends \
    build-essential \
    libsm6 \
    libxext6 \
    libxrender-dev \
    libgl1 \
    libglib2.0-0 \
    && rm -rf /var/lib/apt/lists/*

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

# Copy requirements
COPY requirements.txt .

# Install Python dependencies
RUN pip install --no-cache-dir --upgrade pip && \
    pip install --no-cache-dir -r requirements.txt

# ========== Stage 2: Runtime ==========
FROM python:3.11-slim

# Install runtime dependencies only
RUN apt-get update && apt-get install -y --no-install-recommends \
    libsm6 \
    libxext6 \
    libxrender-dev \
    libgl1 \
    libglib2.0-0 \
    curl \
    && rm -rf /var/lib/apt/lists/*

# Create non-root user
RUN useradd -m -u 1000 appuser

# Set working directory
WORKDIR /app

# Copy virtual environment from builder
COPY --from=builder --chown=appuser:appuser /opt/venv /opt/venv

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

# Ensure /app and all subdirectories are writable by appuser
RUN chown -R appuser:appuser /app

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

# Switch to non-root user
USER appuser

# Health check
HEALTHCHECK --interval=30s --timeout=10s --start-period=40s --retries=3 \
    CMD curl -f http://localhost:7860/health || exit 1

# Run application
CMD ["python", "-m", "uvicorn", "backend:app", "--host", "0.0.0.0", "--port", "7860"]