import type { NextConfig } from "next";
import { readFileSync, existsSync } from "fs";
import { join } from "path";

// 构建时自动加载 Server Actions 加密密钥，避免 "Failed to find Server Action" 部署错误
if (!process.env.NEXT_SERVER_ACTIONS_ENCRYPTION_KEY) {
  const keyPath = join(__dirname, "config", "server-actions.key");
  if (existsSync(keyPath)) {
    process.env.NEXT_SERVER_ACTIONS_ENCRYPTION_KEY = readFileSync(keyPath, "utf8").trim();
  }
}

/** 低配服务器构建：限制并行与 Turbopack 目标内存，避免 pnpm build 把机器拖死 / OOM */
const buildCpuCount = Math.max(
  1,
  Number.parseInt(process.env.NEXT_BUILD_CPUS ?? "1", 10) || 1,
);
const turbopackMemoryMb = Math.max(
  256,
  Number.parseInt(process.env.NEXT_BUILD_TURBOPACK_MEMORY_MB ?? "1536", 10) ||
    1536,
);

const nextConfig: NextConfig = {
  // 预渲染阶段关闭 source map，降低静态生成时内存峰值（需要时可设 NEXT_BUILD_PRERENDER_SOURCE_MAPS=1）
  enablePrerenderSourceMaps:
    process.env.NEXT_BUILD_PRERENDER_SOURCE_MAPS === "1",
  // 局域网访问（如手机 192.168.x.x）时允许跨域请求 _next 资源
  // 需完全重启 dev 服务（Ctrl+C 后 pnpm dev）后生效
  allowedDevOrigins: [
    "192.168.41.222",
    "192.168.41.222:3000",
    "http://192.168.41.222",
    "http://192.168.41.222:3000",
    "http://192.168.41.222:3001",
  ],
  experimental: {
    cpus: buildCpuCount,
    memoryBasedWorkersCount: true,
    turbopackMemoryLimit: turbopackMemoryMb * 1024 * 1024,
    // 仅 next dev（NODE_ENV=development）建议开启，避免栈帧过滤读到 null source map 控制台报错
    // 生产 build 默认关闭以省内存；需要 Sentry 等可设 NEXT_BUILD_TURBOPACK_SOURCE_MAPS=1
    turbopackSourceMaps:
      process.env.NODE_ENV === "development" ||
      process.env.NEXT_BUILD_TURBOPACK_SOURCE_MAPS === "1",
    // 静态页面导出时一次只跑少量页面，降低峰值内存
    staticGenerationMaxConcurrency: 1,
  },
};

export default nextConfig;