# 分层构建：依赖与代码分离，仅代码变更时只重建 COPY 及以后层
FROM node:20-alpine

WORKDIR /app

# 使用国内镜像源，加快安装并减少网络卡死
RUN npm config set registry https://registry.npmmirror.com \
    && npm config set fetch-retries 5 \
    && npm config set fetch-timeout 60000 \
    && npm config set fetch-retry-mintimeout 10000

# 依赖层：只有 package.json / package-lock 变更时才重建
COPY package.json ./
RUN npm install --prefer-offline --no-audit --progress=false

# 代码层：业务代码变更只重建此层及后续 build
COPY . .

ENV NODE_ENV=production
ENV NEXT_TELEMETRY_DISABLED=1

RUN npm run build

EXPOSE 3000

CMD ["npm", "run", "start"]