import { join } from "node:path";
import type { DB, Kysely } from "@umt/db";
import { sql } from "@umt/db";
import type { Config } from "./config.ts";

export interface PreflightProblem {
  check: string;
  message: string;
}

export interface PreflightDeps {
  config: Config;
  db: Kysely<DB>;
  /** 测试可注入;默认取当前进程 uid(Windows 上为 null) */
  uid?: number | null;
}

// 明显的占位符密钥:生产环境拒绝启动
const PLACEHOLDER = /change[-_]?me|replace[-_]?me|dev[-_]?only|example/i;

/** 启动自检:返回问题列表,空数组表示通过。不打印变量值。 */
export async function runPreflight({ config, db, uid = Deno.uid() }: PreflightDeps): Promise<PreflightProblem[]> {
  const problems: PreflightProblem[] = [];
  const prod = config.NODE_ENV === "production";

  if (prod && PLACEHOLDER.test(config.SECRET_MASTER_KEY)) {
    problems.push({ check: "secret", message: "SECRET_MASTER_KEY 仍是占位符,生产环境必须换成随机串" });
  }
  if (prod && uid === 0) {
    problems.push({ check: "user", message: "生产环境不允许以 root 运行" });
  }
  try {
    await sql`select 1`.execute(db);
  } catch (err) {
    problems.push({ check: "db", message: `数据库不可达: ${(err as Error).message}` });
  }
  if (config.WEB_ROOT) {
    try {
      await Deno.stat(join(config.WEB_ROOT, "index.html"));
    } catch {
      problems.push({ check: "web", message: `WEB_ROOT 下没有 index.html: ${config.WEB_ROOT}` });
    }
  }
  return problems;
}