// Shared HTTP helpers. The TV app talks to Radarr, Sonarr, SABnzbd and Trakt
// directly from the browser: all four answer cross-origin requests (CORS).

export class HTTPError extends Error {
  status: number;
  constructor(status: number, message: string) {
    super(message ? `HTTP ${status}: ${message}` : `unexpected response: HTTP ${status}`);
    this.status = status;
  }
}

export class NotConfiguredError extends Error {
  constructor(what: string) {
    super(`${what} is not configured: set its address and API key in Settings`);
  }
}

// request sends a request that gives up after timeoutMs. Network failures
// become an Error naming the host only (the URL may carry an API key).
export async function request(url: string, init: RequestInit = {}, timeoutMs = 30_000): Promise<Response> {
  const ctl = new AbortController();
  const timer = setTimeout(() => ctl.abort(), timeoutMs);
  const outer = init.signal;
  if (outer) {
    if (outer.aborted) ctl.abort();
    else outer.addEventListener("abort", () => ctl.abort());
  }
  try {
    return await fetch(url, { ...init, signal: ctl.signal });
  } catch (e) {
    if (outer?.aborted) throw new DOMException("cancelled", "AbortError");
    if (ctl.signal.aborted) throw new Error(`${hostOf(url)}: no answer within ${Math.round(timeoutMs / 1000)} s`);
    // A browser cannot follow a redirect (e.g. http to https) of a cross-origin
    // request unless the redirect itself allows it; the TUI never notices.
    const hint = url.startsWith("http://") ? "; if the address redirects to https, enter the https address" : "";
    throw new Error(`${hostOf(url)}: cannot connect (${(e as Error).message})${hint}`);
  } finally {
    clearTimeout(timer);
  }
}

export function hostOf(url: string): string {
  try {
    return new URL(url).host;
  } catch {
    return "server";
  }
}

export function isAbort(e: unknown): boolean {
  return e instanceof DOMException && e.name === "AbortError";
}

export function query(params: Record<string, string | number | boolean | undefined>): string {
  const parts: string[] = [];
  for (const [k, v] of Object.entries(params)) {
    if (v !== undefined) parts.push(encodeURIComponent(k) + "=" + encodeURIComponent(String(v)));
  }
  return parts.length ? "?" + parts.join("&") : "";
}

export function trimSlash(u: string): string {
  return u.trim().replace(/\/+$/, "");
}