# Multi-stage build for optimal production image

# Stage 1: Dependencies
FROM node:20-alpine AS deps
RUN apk add --no-cache libc6-compat
WORKDIR /app

# Copy package files
COPY package.json package-lock.json ./

# Install all dependencies (including dev dependencies needed for build)
ENV NODE_ENV=development
RUN npm ci

# Stage 2: Builder
FROM node:20-alpine AS builder
WORKDIR /app

# Copy dependencies from deps stage
COPY --from=deps /app/node_modules ./node_modules
COPY . .

# Set environment variable for build (optional - can be overridden at runtime)
ARG NEXT_PUBLIC_GEMINI_API_KEY
ENV NEXT_PUBLIC_GEMINI_API_KEY=$NEXT_PUBLIC_GEMINI_API_KEY

# Build Next.js application with standalone output
ENV NEXT_TELEMETRY_DISABLED=1
RUN npm run build

# Stage 3: Runner
FROM node:20-alpine AS runner
WORKDIR /app

ENV NODE_ENV=production
ENV NEXT_TELEMETRY_DISABLED=1

# Optional: OCI-Labels für GHCR
LABEL org.opencontainers.image.source="https://github.com/stefan-kp/chess_tutor"
LABEL org.opencontainers.image.title="Chess Tutor"
LABEL org.opencontainers.image.description="AI-based chess tutor using Stockfish and Gemini"

# Create non-root user for security
RUN addgroup --system --gid 1001 nodejs
RUN adduser --system --uid 1001 nextjs

# Copy necessary files from builder
COPY --from=builder /app/public ./public
COPY --from=builder /app/.next/standalone ./
COPY --from=builder /app/.next/static ./.next/static

# Set ownership to non-root user
RUN chown -R nextjs:nodejs /app

# Switch to non-root user
USER nextjs

# Expose port 3050
EXPOSE 3050

# Set port environment variable
ENV PORT=3050
ENV HOSTNAME="0.0.0.0"

# Health check
HEALTHCHECK --interval=30s --timeout=3s --start-period=5s --retries=3 \
  CMD node -e "require('http').get('http://localhost:3050/api/health', (r) => {process.exit(r.statusCode === 200 ? 0 : 1)})" || exit 1

# Start the application
CMD ["node", "server.js"]