import { removeTrackingParameters } from './productUrl';
export const ATX_PARAM = 'atx';
export const ATX_VALUE = '1';

function removeAtx(url: URL): string[] {
  const values: string[] = [];
  for (const key of Array.from(url.searchParams.keys())) {
    if (key.toLowerCase() === ATX_PARAM) {
      values.push(...url.searchParams.getAll(key));
      url.searchParams.delete(key);
    }
  }
  return values;
}

export function withShareLandingParam(cleanUrl: string | null): string | null {
  if (!cleanUrl) return null;
  try {
    const url = new URL(cleanUrl);
    if (url.protocol !== 'https:') return null;
    url.hash = '';
    removeAtx(url);
    removeTrackingParameters(url);
    url.searchParams.set(ATX_PARAM, ATX_VALUE);
    return url.toString();
  } catch { return null; }
}

export function stripShareLandingParam(value: string | null): string | null {
  if (!value) return value;
  try {
    const url = new URL(value);
    return removeAtx(url).length ? url.toString() : value;
  } catch { return value; }
}

let consumed = false;
export function consumeShareLanding(win: Pick<Window, 'location' | 'history'>): boolean {
  if (consumed) return false;
  consumed = true;
  try {
    const url = new URL(win.location.href);
    const values = removeAtx(url);
    if (!values.length) return false;
    try { win.history.replaceState(win.history.state, '', url.pathname + url.search + url.hash); } catch { /* sandboxed history */ }
    return values.includes(ATX_VALUE);
  } catch { return false; }
}