import { env } from './auth-config';
import { sleep } from './gotrue';

export interface MailSummary {
  ID: string;
  Subject: string;
  To: { Address: string }[];
  Created: string;
}

export interface Mail extends MailSummary {
  html: string;
  text: string;
}

async function getJson(path: string): Promise<any> {
  const res = await fetch(`${env.mailpitUrl}/api/v1${path}`);
  if (!res.ok) throw new Error(`Mailpit ${path}: HTTP ${res.status}`);
  return res.json();
}

/** Alle Mails an eine Adresse (Suche per `to:`; nie global loeschen, Tests laufen parallel). */
export async function mailsTo(address: string): Promise<MailSummary[]> {
  const result = await getJson(`/search?query=${encodeURIComponent(`to:"${address}"`)}&limit=50`);
  return (result.messages ?? []) as MailSummary[];
}

export async function countMails(address: string): Promise<number> {
  return (await mailsTo(address)).length;
}

export async function readMail(id: string): Promise<Mail> {
  const m = await getJson(`/message/${id}`);
  return { ID: m.ID, Subject: m.Subject, To: m.To, Created: m.Date ?? '', html: m.HTML ?? '', text: m.Text ?? '' };
}

/**
 * Wartet, bis mindestens `count` Mails an die Adresse vorliegen, und liefert die neueste.
 * Faellt nach `timeoutMs` mit einer aussagekraeftigen Meldung durch.
 */
export async function waitForMail(address: string, count = 1, timeoutMs = 10_000): Promise<Mail> {
  const deadline = Date.now() + timeoutMs;
  let found: MailSummary[] = [];
  while (Date.now() < deadline) {
    found = await mailsTo(address);
    if (found.length >= count) {
      // Mailpit liefert die neueste zuerst.
      return readMail(found[0].ID);
    }
    await sleep(200);
  }
  throw new Error(`Keine ${count}. Mail an ${address} nach ${timeoutMs} ms (vorhanden: ${found.length})`);
}

/**
 * Belegt „es kommt keine (weitere) Mail": wartet ein festes Fenster und zaehlt dann.
 * Nur dort einsetzen, wo die Abwesenheit selbst das Kriterium ist (Krit. 4, 8, 11).
 */
export async function expectMailCount(address: string, expected: number, windowMs = 2_000): Promise<number> {
  await sleep(windowMs);
  const actual = await countMails(address);
  if (actual !== expected) throw new Error(`Mails an ${address}: erwartet ${expected}, vorhanden ${actual}`);
  return actual;
}

/** Link aus der Mail: `.../auth/confirm?token_hash=...&type=email|recovery` (HTML-Entities decodiert). */
export function extractConfirmLink(mail: Mail): URL {
  const decoded = mail.html.replace(/&amp;/g, '&');
  const match = decoded.match(/https?:\/\/[^"'\s<]+\/auth\/confirm\?[^"'\s<]+/);
  if (!match) throw new Error(`Kein Bestaetigungslink in der Mail "${mail.Subject}"`);
  return new URL(match[0]);
}

export function extractTokenHash(mail: Mail): { tokenHash: string; type: string; link: URL } {
  const link = extractConfirmLink(mail);
  const tokenHash = link.searchParams.get('token_hash');
  const type = link.searchParams.get('type');
  if (!tokenHash || !type) throw new Error('token_hash oder type fehlen im Link');
  return { tokenHash, type, link };
}