# Multi-stage Dockerfile for Next.js Production Build
# Optimized for Next.js 15 with App Router

FROM node:20-alpine AS base

# Install dependencies only when needed
FROM base AS deps
RUN apk add --no-cache libc6-compat
WORKDIR /app

# Copy package files
COPY package.json package-lock.json* ./
RUN npm ci

# Rebuild the source code only when needed
FROM base AS builder
WORKDIR /app
COPY --from=deps /app/node_modules ./node_modules
COPY . .

# Set build-time environment variables
ENV NEXT_TELEMETRY_DISABLED 1

# Build Next.js application
RUN npm run build

# Production image, copy all the files and run next
FROM base AS runner
WORKDIR /app

ENV NODE_ENV production
ENV NEXT_TELEMETRY_DISABLED 1

# Create nextjs user
RUN addgroup --system --gid 1001 nodejs
RUN adduser --system --uid 1001 nextjs

# Copy built application
COPY --from=builder /app/public ./public

# Set the correct permission for prerender cache
RUN mkdir .next
RUN chown nextjs:nodejs .next

# Automatically leverage output traces to reduce image size
# https://nextjs.org/docs/advanced-features/output-file-tracing
COPY --from=builder --chown=nextjs:nodejs /app/.next/standalone ./
COPY --from=builder --chown=nextjs:nodejs /app/.next/static ./.next/static

USER nextjs

EXPOSE 3000

ENV PORT 3000
ENV HOSTNAME "0.0.0.0"

# Run Next.js server
CMD ["node", "server.js"]