# Multi-stage build for Next.js application
# Stage 1: Build stage
FROM node:20-alpine AS builder

WORKDIR /app

# NEXT_PUBLIC_* vars are inlined at build time — must be passed as build args
ARG NEXT_PUBLIC_SITE_URL
ENV NEXT_PUBLIC_SITE_URL=$NEXT_PUBLIC_SITE_URL

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

# Install dependencies
RUN npm ci --prefer-offline --no-audit

# Copy source code
COPY . .

# Build the application
RUN npm run build

# Stage 2: Production runtime
FROM node:20-alpine AS runner

WORKDIR /app

# Set production environment
ENV NODE_ENV=production
# Next standalone otherwise inherits Docker's container-ID HOSTNAME and only binds
# to the container IP. Bind explicitly to all interfaces for port publishing and healthchecks.
ENV HOSTNAME=0.0.0.0

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

# Copy built application from builder stage
COPY --from=builder /app/.next/standalone ./
COPY --from=builder /app/.next/static ./.next/static
COPY --from=builder /app/public ./public

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

# Expose port
EXPOSE 3000

# Health check
HEALTHCHECK --interval=30s --timeout=5s --retries=5 \
  CMD wget -qO- http://127.0.0.1:3000/api/health || exit 1

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