# Observatory Simulation - Multi-stage Docker Build

# Build Stage
FROM node:20-alpine AS builder

LABEL maintainer="Observatory Simulation"
LABEL description="Teleskop und Kuppel Simulation mit WebSocket-Architektur"

WORKDIR /app

# Kopiere package files für optimale Layer-Caching
COPY package*.json ./

# Installiere nur Production Dependencies
RUN npm ci --only=production && npm cache clean --force

# Production Stage
FROM node:20-alpine AS production

# Erstelle non-root user für Sicherheit
RUN addgroup -g 1001 -S nodejs && \
    adduser -S observatory -u 1001

WORKDIR /app

# Kopiere node_modules aus Build Stage
COPY --from=builder --chown=observatory:nodejs /app/node_modules ./node_modules

# Kopiere Application Code
COPY --chown=observatory:nodejs server.js ./
COPY --chown=observatory:nodejs public ./public/

# Wechsle zu non-root user
USER observatory

# Expose Port für WebSocket Server
EXPOSE 3005

# Health Check für Container-Monitoring
HEALTHCHECK --interval=30s --timeout=3s --start-period=5s --retries=3 \
    CMD node -e "require('http').get('http://localhost:3005', (res) => { process.exit(res.statusCode === 200 ? 0 : 1) }).on('error', () => process.exit(1))"

# Starte Observatory Simulation
CMD ["node", "server.js"]