import { parseArgs } from "node:util";
import { createDb, migrateToLatest } from "@umt/db";
import denoJson from "../deno.json" with { type: "json" };
import { loadConfig } from "./config.ts";
import { createApp } from "./http/app.ts";
import { EventBus } from "./http/sse.ts";
import { createLogger } from "./logger.ts";
import { runPreflight } from "./preflight.ts";
import { startWorker } from "./worker/index.ts";

// api/worker/all 是常驻角色;migrate/preflight/probe 是容器入口脚本用的一次性子命令
const Roles = ["api", "worker", "all", "migrate", "preflight", "probe"] as const;
type Role = (typeof Roles)[number];

const { values } = parseArgs({ args: Deno.args, options: { role: { type: "string", default: "all" } }, strict: true });
const role = values.role as Role;
if (!Roles.includes(role)) {
  console.error(`--role 必须是 ${Roles.join("|")}`);
  Deno.exit(2);
}

// 健康探测:只打本机回环端口,不需要完整配置(HEALTHCHECK 用,镜像里不装 curl)
if (role === "probe") {
  const port = Deno.env.get("PORT") ?? "4380";
  try {
    const res = await fetch(`http://127.0.0.1:${port}/api/v1/health`, { signal: AbortSignal.timeout(3000) });
    const body = (await res.json()) as { data?: { status?: string } };
    Deno.exit(res.ok && body.data?.status === "ok" ? 0 : 1);
  } catch {
    Deno.exit(1);
  }
}

let config: ReturnType<typeof loadConfig>;
try {
  config = loadConfig();
} catch (err) {
  console.error((err as Error).message);
  Deno.exit(2);
}

const logger = createLogger({
  level: config.LOG_LEVEL,
  pretty: config.NODE_ENV === "development" && Deno.stdout.isTerminal(),
});
const db = createDb({ connectionString: config.DATABASE_URL });

if (role === "migrate" || role === "preflight") {
  let code = 0;
  try {
    if (role === "migrate") {
      const { results } = await migrateToLatest(db);
      for (const r of results ?? []) logger.info({ migration: r.migrationName, status: r.status }, "migration");
      logger.info({ applied: results?.length ?? 0 }, "迁移完成");
    } else {
      const problems = await runPreflight({ config, db });
      for (const p of problems) logger.error({ check: p.check }, p.message);
      if (problems.length) code = 1;
      else logger.info("启动自检通过");
    }
  } catch (err) {
    logger.error({ err }, `${role} 失败`);
    code = 1;
  } finally {
    await db.destroy();
  }
  Deno.exit(code);
}

const bus = new EventBus();
const stops: Array<() => Promise<void>> = [];

if (role === "api" || role === "all") {
  const app = createApp({
    config,
    logger,
    bus,
    db,
    role,
    version: denoJson.version,
    ...(config.WEB_ROOT ? { webRoot: config.WEB_ROOT } : {}),
  });
  const ac = new AbortController();
  const server = Deno.serve(
    {
      port: config.PORT,
      hostname: config.HOST,
      signal: ac.signal,
      onListen: ({ port }) =>
        logger.info(
          { port, role, webRoot: config.WEB_ROOT ?? null },
          `API 已启动 http://localhost:${port}/api/v1/health`,
        ),
    },
    app.fetch,
  );
  stops.push(async () => {
    // abort 后 Deno.serve 会断开 SSE 等长连接,finished 在所有连接关闭后 resolve
    ac.abort();
    await server.finished;
  });
}
if (role === "worker" || role === "all") {
  const worker = startWorker({ logger, heartbeatMs: config.WORKER_HEARTBEAT_MS, bus });
  stops.push(worker.stop);
}

let stopping = false;
async function shutdown(signal: Deno.Signal) {
  if (stopping) return;
  stopping = true;
  logger.info({ signal }, "正在退出");
  // 兜底:10 秒内没退干净就强退,避免容器 stop 超时被 SIGKILL
  const force = setTimeout(() => Deno.exit(1), 10_000);
  await Promise.allSettled(stops.map((s) => s()));
  await db.destroy();
  clearTimeout(force);
  Deno.exit(0);
}
Deno.addSignalListener("SIGINT", () => void shutdown("SIGINT"));
Deno.addSignalListener("SIGTERM", () => void shutdown("SIGTERM"));