import { mkdir, readFile, rm, writeFile } from "node:fs/promises";
import { join } from "node:path";
import { defineCommand } from "citty";
import { apiRequest, type ApiRequestInit } from "../lib/api";
import type { MaintenanceStatus } from "../shared/api";

type Request = <T>(path: string, init?: ApiRequestInit) => Promise<T>;
type Confirmation = (host: string) => Promise<boolean>;
const confirmationPath = join(
  process.env.XDG_RUNTIME_DIR ?? "/tmp",
  "kuber",
  "maintenance-confirmation",
);
const TTL_MS = 60_000;

async function confirmed(host: string): Promise<boolean> {
  try {
    const value = JSON.parse(await readFile(confirmationPath, "utf8")) as {
      host?: string;
      expiresAt?: number;
    };
    if (
      value.host === host &&
      typeof value.expiresAt === "number" &&
      value.expiresAt > Date.now()
    ) {
      await rm(confirmationPath, { force: true });
      return true;
    }
  } catch {}
  await mkdir(join(confirmationPath, ".."), { recursive: true, mode: 0o700 });
  await writeFile(
    confirmationPath,
    JSON.stringify({ host, expiresAt: Date.now() + TTL_MS }),
    { mode: 0o600 },
  );
  return false;
}

export async function runMaintenance(
  host: string,
  request: Request = apiRequest,
  confirm: Confirmation = confirmed,
): Promise<MaintenanceStatus> {
  const status = await request<MaintenanceStatus>(
    `/maintenance/${encodeURIComponent(host)}`,
  );
  if (!(await confirm(status.host))) {
    console.log(
      `${status.host} maintenance is currently ${status.enabled ? "\x1b[31mON\x1b[0m" : "\x1b[32mOFF\x1b[0m"}, run this command again to toggle.`,
    );
    return status;
  }
  const result = await request<MaintenanceStatus>(
    `/maintenance/${encodeURIComponent(status.host)}`,
    { method: "POST", json: { enabled: !status.enabled } },
  );
  console.log(
    `${result.host} maintenance is now ${result.enabled ? "\x1b[31mON\x1b[0m" : "\x1b[32mOFF\x1b[0m"}`,
  );
  return result;
}

export const maintenance = defineCommand({
  meta: {
    name: "maintenance",
    description: "Toggle a global hostname maintenance override",
  },
  args: {
    host: { type: "positional", required: true, description: "DNS hostname" },
  },
  async run({ args }) {
    await runMaintenance(args.host);
  },
});