export type TenantHostFields = {
  domain?: string | null;
  domains?: unknown;
  adminUrl?: string | null;
  appUrl?: string | null;
  nodeServer?: string | null;
};

export function normalizeTenantHost(value?: string | null): string {
  if (!value) return '';
  return String(value)
    .trim()
    .toLowerCase()
    .replace(/^https?:\/\//, '')
    .split('/')[0]
    .split(':')[0]
    .replace(/\.$/, '');
}

/** aliases JSON array, object map, CSV, or a single host/URL */
export function readHostList(raw: unknown): string[] {
  if (!raw) return [];
  if (Array.isArray(raw)) return raw.flatMap((item) => readHostList(item));
  if (typeof raw === 'object') {
    return Object.values(raw as Record<string, unknown>).flatMap(readHostList);
  }
  const text = String(raw).trim();
  if (!text) return [];
  if (
    (text.startsWith('[') && text.endsWith(']')) ||
    (text.startsWith('{') && text.endsWith('}'))
  ) {
    try {
      return readHostList(JSON.parse(text));
    } catch {
      /* fall through */
    }
  }
  return text
    .split(/[\s,;]+/)
    .map((item) => item.trim())
    .filter(Boolean);
}

function looksLikeHostname(value: string): boolean {
  if (!value.includes('.')) return false;
  if (/^09\d{9}$/.test(value)) return false;
  return true;
}

function hostsEqual(left: string, right: string): boolean {
  if (!left || !right) return false;
  if (left === right) return true;
  return left.replace(/^www\./, '') === right.replace(/^www\./, '');
}

/** new.gholaktala.ir belongs to tenant domain gholaktala.ir — not via shared nodeServer. */
function isSubdomainOf(host: string, parent: string): boolean {
  const child = normalizeTenantHost(host);
  const root = normalizeTenantHost(parent).replace(/^www\./, '');
  if (!child || !root || !root.includes('.')) return false;
  return child === root || child.endsWith('.' + root);
}

export type TenantHostMatchMode = 'full' | 'hmac';

/**
 * full: get_user — دامنه، alias، app/admin/node.
 * hmac: فقط دامنهٔ اصلی نسخه (و ساب‌دامنهٔ همان). adminUrl مشترک
 * (k.montzar.ir روی نسخهٔ app.gholaktala.ir) هویت نیست.
 */
export function scoreTenantHost(
  tenant: TenantHostFields,
  hostRaw: string,
  mode: TenantHostMatchMode = 'full',
): number {
  const host = normalizeTenantHost(hostRaw);
  if (!host) return 0;
  const eq = (raw?: string | null) =>
    hostsEqual(normalizeTenantHost(raw), host);

  if (eq(tenant.domain)) return 100;
  if (mode === 'hmac') {
    if (tenant.domain && isSubdomainOf(host, tenant.domain)) return 75;
    return 0;
  }

  for (const alias of readHostList(tenant.domains)) {
    if (eq(alias)) return 90;
  }
  for (const value of readHostList(tenant.appUrl)) {
    if (eq(value)) return 80;
  }
  if (tenant.domain && isSubdomainOf(host, tenant.domain)) return 75;
  for (const alias of readHostList(tenant.domains)) {
    if (isSubdomainOf(host, alias)) return 72;
  }
  for (const value of readHostList(tenant.adminUrl)) {
    const normalized = normalizeTenantHost(value);
    if (looksLikeHostname(normalized) && hostsEqual(normalized, host)) {
      return 50;
    }
  }
  for (const value of readHostList(tenant.nodeServer)) {
    if (eq(value)) return 10;
  }
  return 0;
}

export function findTenantForHost<T extends TenantHostFields>(
  tenants: T[],
  host: string,
  mode: TenantHostMatchMode = 'full',
): T | undefined {
  const scored = tenants
    .map((row) => ({ row, score: scoreTenantHost(row, host, mode) }))
    .filter((item) => item.score > 0)
    .sort((a, b) => b.score - a.score);
  if (!scored.length) return undefined;

  const best = scored[0].score;
  const tied = scored.filter((item) => item.score === best);
  if (tied.length !== 1) return undefined;
  return tied[0].row;
}