# STAGE 1: Base (Heavy Dependencies)
FROM python:3.10-slim as base
WORKDIR /app
# Install system deps if needed (e.g., usually needed for cv2 or weird numpy versions)
# RUN apt-get update && apt-get install -y --no-install-recommends gcc libgomp1

COPY requirements.txt .
# 1. Install Torch (Heavy - Cached in this layer)
RUN pip install --no-cache-dir torch --index-url https://download.pytorch.org/whl/cpu
# 2. Install other Prod deps
RUN pip install --no-cache-dir -r requirements.txt

# STAGE 2: Test (Needs App Code + Tests)
FROM base as test
# 1. Install Test Tools
RUN pip install pytest flake8 httpx

# 2. COPY THE APP CODE (Crucial Step!)
# The tests need to import 'main', so main.py must be here.
COPY main.py /app/

# 3. Copy Tests
COPY tests/ /app/tests/

ENV PYTHONPATH=/app
# 4. Run Linting and Tests
RUN flake8 . --count --select=E9,F63,F7,F82 --show-source --statistics
RUN pytest tests/

# STAGE 3: Production (Final Image)
FROM base as prod
# We start fresh from 'base'. The junk from 'test' stage is gone.
COPY main.py /app/
# Note: We do NOT copy tests/ here to keep prod image smaller
EXPOSE 8000
CMD ["uvicorn", "main:app", "--host", "0.0.0.0", "--port", "7860"]