FROM python:3.11-slim

# Metadata
LABEL maintainer="multi-doc-rag"
LABEL description="Multi-Document RAG System - Slim build, no GPU/torch"

# Set environment variables
ENV PYTHONDONTWRITEBYTECODE=1
ENV PYTHONUNBUFFERED=1
ENV PIP_NO_CACHE_DIR=1

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

# Set working directory
WORKDIR /app

# Copy requirements first for Docker layer caching
COPY requirements.txt .

# Install Python dependencies (NO torch, NO transformers)
RUN pip install --no-cache-dir -r requirements.txt && \
    pip uninstall -y torch torchvision torchaudio transformers sentence-transformers 2>/dev/null || true

# Create upload, evaluation, and log directories with full read/write permissions
# (Crucial for Hugging Face Spaces which runs under user ID 1000)
RUN mkdir -p /app/data/uploads /app/evaluation/reports /app/logs && \
    chmod -R 777 /app/data /app/evaluation /app/logs

# Copy application code
COPY . .

# Make the start script executable
RUN chmod +x /app/start.sh

# Expose the default web port (7860 for Hugging Face, 10000 for Render)
EXPOSE 7860

# Run the backend & frontend supervisor script
CMD ["./start.sh"]