# ============================================
# Stage 1: Build React Frontend
# ============================================
FROM node:20-alpine AS frontend-build

WORKDIR /build/frontend
COPY frontend/package.json frontend/package-lock.json* ./
RUN npm install --legacy-peer-deps
COPY frontend/ ./
RUN npm run build

# ============================================
# Stage 2: Python Backend + Serve Frontend
# ============================================
FROM python:3.11-slim

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

WORKDIR /app

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

# Copy backend code
COPY backend/ ./backend/

# Copy built frontend
COPY --from=frontend-build /build/frontend/dist ./frontend/dist

# Pre-download the ChromaDB embedding model so first request is fast
RUN python -c "\
import chromadb; \
c = chromadb.Client(); \
col = c.create_collection('_warmup'); \
col.add(documents=['warmup embedding model'], ids=['0']); \
c.delete_collection('_warmup'); \
print('Embedding model cached.')"

# Create persistent data directory
RUN mkdir -p /data/chromadb /data/uploads

ENV PYTHONUNBUFFERED=1

EXPOSE 80

CMD ["python", "-m", "uvicorn", "backend.main:app", "--host", "0.0.0.0", "--port", "80", "--workers", "1"]