// Was src/backend/database/routes/tailscale-routes.ts, moved here and
// rewritten to register itself via the shared /tailscale dispatcher
// (src/backend/database/routes/tailscale-dispatch.ts) instead of taking a
// direct reference to the app instance, the same way fleets does.

import { Router } from "express";
import { AuthManager } from "../../../src/backend/utils/auth-manager.js";
import { apiLogger } from "../../../src/backend/utils/logger.js";
import { fetchWithProxy } from "../../../src/backend/utils/proxy-agent.js";
import { createCurrentSettingsRepository } from "../../../src/backend/database/repositories/factory.js";
import {
  registerTailscaleRouter,
  unregisterTailscaleRouter,
} from "../../../src/backend/database/routes/tailscale-dispatch.js";

interface TailscaleDevice {
  id: string;
  name: string;
  hostname: string;
  addresses: string[];
  os: string;
  lastSeen: string;
}

interface TailscaleAPIDevice {
  id: string;
  name: string;
  hostname: string;
  addresses: string[];
  os: string;
  lastSeen: string;
  nodeId?: string;
}

const DEFAULT_TAILSCALE_API_BASE = "https://api.tailscale.com/api/v2";

export const router = Router();

const authManager = AuthManager.getInstance();
const authenticateJWT = authManager.createAuthMiddleware();

function normalizeApiBase(raw: string | null): string {
  const trimmed = (raw ?? "").trim().replace(/\/+$/, "");
  return trimmed || DEFAULT_TAILSCALE_API_BASE;
}

/**
 * @openapi
 * /tailscale/devices:
 *   get:
 *     summary: List Tailscale devices
 *     description: Returns the list of devices in the configured tailnet using the stored API key.
 *     tags:
 *       - Tailscale
 *     responses:
 *       200:
 *         description: List of tailnet devices.
 *         content:
 *           application/json:
 *             schema:
 *               type: object
 *               properties:
 *                 devices:
 *                   type: array
 *                   items:
 *                     type: object
 *       500:
 *         description: Failed to fetch Tailscale devices.
 */
router.get("/devices", authenticateJWT, async (_req, res) => {
  try {
    const settingsRepo = createCurrentSettingsRepository();
    const apiKey = (await settingsRepo.get("tailscale_api_key")) ?? "";
    if (!apiKey) {
      return res.json({ devices: [], hasApiKey: false });
    }
    const apiBase = normalizeApiBase(
      await settingsRepo.get("tailscale_api_base_url"),
    );

    const url = `${apiBase}/tailnet/-/devices?fields=all`;
    const response = await fetchWithProxy(url, {
      headers: {
        Authorization: `Bearer ${apiKey}`,
        "User-Agent": "Termix/1.0",
      },
    });

    if (!response.ok) {
      apiLogger.warn("Tailscale API returned non-OK status", {
        operation: "tailscale_devices",
        status: response.status,
      });
      if (response.status === 401 || response.status === 403) {
        return res.status(401).json({
          error: "Invalid Tailscale API key",
          devices: [],
          hasApiKey: true,
        });
      }
      return res.status(502).json({
        error: "Tailscale API error",
        devices: [],
        hasApiKey: true,
      });
    }

    const data = (await response.json()) as { devices: TailscaleAPIDevice[] };

    const devices: TailscaleDevice[] = (data.devices ?? []).map((d) => ({
      id: d.id,
      name: d.name,
      hostname: d.hostname,
      addresses: d.addresses ?? [],
      os: d.os,
      lastSeen: d.lastSeen,
    }));

    res.json({ devices, hasApiKey: true });
  } catch (err) {
    apiLogger.error("Failed to fetch Tailscale devices", err, {
      operation: "tailscale_devices",
    });
    res.status(500).json({
      error: "Failed to fetch Tailscale devices",
      devices: [],
      hasApiKey: true,
    });
  }
});

/** Called from activate(). Mounts this router at /tailscale via the shared
 * dispatcher. */
export function startTailscaleService(): void {
  registerTailscaleRouter(router);
}

/** Called from deactivate(). /tailscale/* falls back to 404 until
 * reactivated. */
export function stopTailscaleService(): void {
  unregisterTailscaleRouter();
}