# =============================================================================
# PaintPlus — GPU Container (NVIDIA CUDA)
#
# Usage:
#   docker compose -f docker-compose.gpu.yml up --build
#
# Requirements on host:
#   - NVIDIA driver ≥ 525 (for CUDA 12.x)
#   - nvidia-container-toolkit installed and configured
#   - docker compose v2 (or docker-compose with GPU device support)
#
# AMD ROCm users: replace the pytorch base image with a ROCm variant, e.g.
#   rocm/pytorch:latest   (and remove the nvidia-smi check below)
# =============================================================================

# ── Stage 1: Build miniPaint frontend ────────────────────────────────────────
FROM node:20-alpine AS frontend-build

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

# ── Stage 2: PyTorch CUDA runtime ────────────────────────────────────────────
# pytorch/pytorch already includes torch + torchvision built for CUDA 12.1.
# Using the runtime (not devel) image keeps the layer lean.
FROM pytorch/pytorch:2.1.0-cuda12.1-cudnn8-runtime

WORKDIR /app

# System dependencies
RUN apt-get update && apt-get install -y --no-install-recommends \
    libgl1 \
    libglib2.0-0 \
    libsm6 \
    libxext6 \
    libxrender-dev \
    libgomp1 \
    wget \
    git \
    && rm -rf /var/lib/apt/lists/*

# Install Python dependencies — base + GPU extras
# BUILDID forces pip layers to re-run when you need fresh packages without a full --no-cache:
#   BUILDID=$(date +%s) docker compose -f docker-compose.gpu.yml up --build
ARG BUILDID=1
COPY backend/requirements.txt .
COPY backend/requirements.gpu.txt .
RUN echo "BUILDID=$BUILDID" && pip install --no-cache-dir -r requirements.txt
RUN echo "BUILDID=$BUILDID" && pip install --no-cache-dir -r requirements.gpu.txt

# Smoke-test rembg (model downloads on first use)
RUN python -c "from rembg import remove; print('rembg OK')" \
    || echo "WARNING: rembg unavailable — Remove Background disabled"

# Smoke-test ben2 (weights download from HuggingFace on first use)
RUN python -c "import ben2; print('ben2 OK')" \
    || echo "WARNING: ben2 unavailable — Remove Background falls back to U2Net/rembg"

# Copy backend application
COPY backend/ .

# Entrypoint
COPY backend/entrypoint.sh /entrypoint.sh
RUN chmod +x /entrypoint.sh

# Scripts (SAM download, DB init, GPU setup, etc.)
COPY scripts/ /scripts/
RUN chmod +x /scripts/*.py 2>/dev/null || true

# Copy built frontend from Stage 1
COPY --from=frontend-build /frontend/index.html /app/static/
COPY --from=frontend-build /frontend/dist        /app/static/dist
COPY --from=frontend-build /frontend/images      /app/static/images
COPY --from=frontend-build /frontend/src/css     /app/static/src/css

# Persistent data directories
RUN mkdir -p /app/data/projects /app/data/patches /app/data/models

EXPOSE 8000
ENTRYPOINT ["/entrypoint.sh"]