# Stage 1: Install dependencies
FROM node:20-alpine AS deps
RUN corepack enable && corepack prepare pnpm@10.33.2 --activate
WORKDIR /app
COPY package.json pnpm-lock.yaml ./
RUN pnpm install --frozen-lockfile --prod=false

# Stage 1b: Production dependency tree in a flat (hoisted) node_modules.
# Hoisted = symlink-free, so a Docker COPY into the runner is faithful
# (copying pnpm's default symlinked layout dereferences and breaks
# transitive resolution); complete = the custom socket.io server's deps
# (engine.io, accepts, ws, ...) all resolve at runtime.
FROM node:20-alpine AS prod-deps
RUN corepack enable && corepack prepare pnpm@10.33.2 --activate
WORKDIR /app
COPY package.json pnpm-lock.yaml ./
RUN echo "node-linker=hoisted" > .npmrc && pnpm install --frozen-lockfile --prod

# Stage 2: Build the application
FROM node:20-alpine AS builder
RUN corepack enable && corepack prepare pnpm@10.33.2 --activate
WORKDIR /app
COPY --from=deps /app/node_modules ./node_modules
COPY . .
# NODE_ENV=production in the builder makes `next build` and any code
# branching on isProd deterministic (build-auditor M9). Without this,
# CSP and other prod-only paths would compile under whatever NODE_ENV
# the host carried in.
ENV NODE_ENV=production
ENV NEXT_TELEMETRY_DISABLED=1
ENV SKIP_ENV_VALIDATION=1
RUN pnpm build

# Stage 3: Production runner
FROM node:20-alpine AS runner
RUN addgroup --system --gid 1001 nodejs && adduser --system --uid 1001 nextjs
WORKDIR /app
ENV NODE_ENV=production
ENV NEXT_TELEMETRY_DISABLED=1
COPY --from=builder --chown=nextjs:nodejs /app/.next/standalone ./
COPY --from=builder --chown=nextjs:nodejs /app/.next/static ./.next/static
COPY --from=builder --chown=nextjs:nodejs /app/public ./public
COPY --from=builder --chown=nextjs:nodejs /app/dist/server.js ./server-custom.js
# The custom socket.io server (server-custom.js, built with esbuild
# --packages=external) resolves socket.io and its FULL transitive closure
# (engine.io → accepts/ws/cors, @socket.io/redis-adapter, ...) from
# node_modules at runtime. The Next tracer omits these from
# .next/standalone because no Next route imports the socket server, and
# cherry-copying just socket.io/ leaves its deps unresolved
# (MODULE_NOT_FOUND 'accepts'). Overlay the complete prod dependency tree
# (flat/hoisted layout → symlink-safe copy) on top of the traced subset.
COPY --from=prod-deps --chown=nextjs:nodejs /app/node_modules ./node_modules
USER nextjs
EXPOSE 3000
HEALTHCHECK --interval=30s --timeout=5s --start-period=20s --retries=3 \
  CMD wget --no-verbose --tries=1 --spider http://localhost:${PORT:-3000}/api/health || exit 1
CMD ["node", "server-custom.js"]