FROM node:18-alpine

WORKDIR /app

# Copy npm config first
COPY .npmrc ./

# Copy package files
COPY backend/package*.json ./

# Install dependencies with retry logic
RUN npm cache clean --force && \
    npm install --no-optional --legacy-peer-deps 2>&1 | tail -20 && \
    ls -la node_modules/express || npm install express && \
    test -d node_modules/express || (echo "FATAL: express not found" && exit 1)

# Copy application code
COPY backend/src ./src
COPY frontend ./frontend

EXPOSE 4001

CMD ["node", "src/server.js"]