/**
 * PocketBase client for MEGA INFRASTRUCTURE.
 *
 * Two clients are exported:
 *   - `pb`        — browser/client-safe client (uses NEXT_PUBLIC_POCKETBASE_URL).
 *                   Reads its auth token from localStorage so the user
 *                   stays signed in across reloads.
 *   - `pbAdmin`   — server-only client authenticated as the superuser.
 *                   Uses POCKETBASE_ADMIN_EMAIL + POCKETBASE_ADMIN_PASSWORD
 *                   from the server environment and caches the token in
 *                   module scope.
 *
 * Always import from this file. Do not call `new Pocketbase(...)` elsewhere.
 */
import PocketBase from "pocketbase";
import { billableTimesheetRequest } from "./timesheet-dedup";

export const PB_URL =
  process.env.NEXT_PUBLIC_POCKETBASE_URL ?? "http://127.0.0.1:8090";

/**
 * Browser-reachable PocketBase base URL for fetching uploaded files.
 * PB file URLs (/api/files/<collection>/<record>/) are served by the
 * same host the browser uses to talk to PB, so we derive this from
 * NEXT_PUBLIC_POCKETBASE_URL rather than hardcoding the prod hostname.
 * Falls back to the same localhost default as PB_URL so dev "just works".
 */
export const PB_BASE_URL =
  process.env.NEXT_PUBLIC_POCKETBASE_URL ?? "http://127.0.0.1:8090";

const AUTH_STORAGE_KEY = "mega-pb-auth";

/* ------------------------------------------------------------------ */
/* Browser client                                                      */
/* ------------------------------------------------------------------ */

export const pb = new PocketBase(PB_URL);
pb.beforeSend = billableTimesheetRequest;

// Restore persisted auth on first access (browser only).
if (typeof window !== "undefined") {
  try {
    const raw = window.localStorage.getItem(AUTH_STORAGE_KEY);
    if (raw) {
      const parsed = JSON.parse(raw) as { token?: string; model?: unknown };
      if (parsed.token) {
        pb.authStore.save(parsed.token, parsed.model as never);
      }
    }
  } catch {
    /* localStorage may be blocked — ignore */
  }
  pb.authStore.onChange(() => {
    try {
      if (pb.authStore.isValid) {
        window.localStorage.setItem(
          AUTH_STORAGE_KEY,
          JSON.stringify({ token: pb.authStore.token, model: pb.authStore.model })
        );
      } else {
        window.localStorage.removeItem(AUTH_STORAGE_KEY);
      }
    } catch {
      /* ignore */
    }
  }, true);
}

/* ------------------------------------------------------------------ */
/* Admin client (server-only)                                          */
/* ------------------------------------------------------------------ */

let _adminClient: PocketBase | null = null;
let _adminToken: string | null = null;

export async function pbAdmin(): Promise<PocketBase> {
  if (_adminClient && _adminToken) return _adminClient;

  const email = process.env.POCKETBASE_ADMIN_EMAIL;
  const password = process.env.POCKETBASE_ADMIN_PASSWORD;
  const presetToken = process.env.POCKETBASE_ADMIN_TOKEN;

  if (!email || !password) {
    throw new Error(
      "pbAdmin(): POCKETBASE_ADMIN_EMAIL / POCKETBASE_ADMIN_PASSWORD are not set in the server environment."
    );
  }

  const client = new PocketBase(PB_URL);
  client.beforeSend = billableTimesheetRequest;
  // Disable SDK auto-cancellation on the admin client. Auto-cancel is a
  // browser feature (cancels in-flight requests when the user navigates
  // away) keyed off (method + URL-path). On the server, the module-level
  // client cache means every concurrent route handler shares ONE client
  // instance, so the second concurrent request to the same endpoint
  // aborts the first one and we get cascading AbortError 500s - visible
  // as soon as anything fires parallel requests (e.g. multi-file upload,
  // or a Promise.all over PB collections). Server-side requests have
  // nothing to navigate away from, so disabling is safe.
  //
  // The field is `private` in the public .d.ts even though the runtime
  // supports it. The double-cast (object -> never -> our shape) is the
  // only way to write to a `private` field on a class outside that class
  // without `any`.
  (client as unknown as { enableAutoCancellation: boolean }).enableAutoCancellation = false;
  if (presetToken) {
    client.authStore.save(presetToken, null);
  } else {
    await client.collection("_superusers").authWithPassword(email, password);
  }
  _adminClient = client;
  _adminToken = client.authStore.token;
  return client;
}

/* ------------------------------------------------------------------ */
/* Helpers                                                             */
/* ------------------------------------------------------------------ */

export type { RecordModel } from "pocketbase";