# ---- Build stage ----
FROM python:3.12-slim-bookworm AS builder

WORKDIR /app

# Install build dependencies
RUN apt-get update && apt-get install -y --no-install-recommends \
    build-essential \
    libpq-dev \
    && rm -rf /var/lib/apt/lists/*

# Copy requirements first for better caching
COPY requirements.txt requirements-reranker.txt ./

# Create virtual environment and install dependencies
RUN python -m venv /opt/venv
ENV PATH="/opt/venv/bin:$PATH"
RUN pip install --no-cache-dir --upgrade pip && \
    pip install --no-cache-dir -r requirements.txt && \
    pip install --no-cache-dir -r requirements-reranker.txt || \
    echo "WARNING: reranker dependencies not installed (torch/sentence-transformers)"

# ---- Runtime stage ----
FROM python:3.12-slim-bookworm

WORKDIR /app

# Install runtime dependencies for WeasyPrint (PDF generation)
RUN apt-get update && apt-get install -y --no-install-recommends \
    libpango-1.0-0 \
    libpangocairo-1.0-0 \
    libgdk-pixbuf-2.0-0 \
    libffi-dev \
    shared-mime-info \
    curl \
    && rm -rf /var/lib/apt/lists/*

# Copy virtual environment from builder
COPY --from=builder /opt/venv /opt/venv
ENV PATH="/opt/venv/bin:$PATH"

# Create non-root user
RUN useradd --create-home --shell /bin/bash appuser

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

# Switch to non-root user
USER appuser

# Environment variables
ENV PYTHONUNBUFFERED=1
ENV PYTHONDONTWRITEBYTECODE=1

# Expose port
EXPOSE 8002

# Health check
HEALTHCHECK --interval=30s --timeout=3s --start-period=5s --retries=3 \
    CMD curl -f http://127.0.0.1:8002/health || exit 1

# Run the application
CMD ["uvicorn", "main:app", "--host", "0.0.0.0", "--port", "8002"]