let statisticsLocalSessionKey = "";
let statisticsLocalSessionRef = "";

export function uuidv4() {
  // copied from https://stackoverflow.com/a/2117523/669561
  // @ts-ignore
  return ([1e7] + -1e3 + -4e3 + -8e3 + -1e11).replace(/[018]/g, (c) =>
    (c ^ (crypto.getRandomValues(new Uint8Array(1))[0] & (15 >> (c / 4)))).toString(16)
  );
}

export function getLocalSessionKey() {
  return (
    window.sessionStorage.getItem("statisticsLocalSessionKey") ||
    statisticsLocalSessionKey ||
    ""
  );
}

export function generateLocalSessionKey() {
  let localSessionKey =
    window.sessionStorage.getItem("statisticsLocalSessionKey") ||
    statisticsLocalSessionKey;
  if (!localSessionKey) {
    localSessionKey = uuidv4();
  }
  statisticsLocalSessionKey = localSessionKey;
  window.sessionStorage.setItem("statisticsLocalSessionKey", localSessionKey);

  return localSessionKey;
}

export function getLocalSessionRef() {
  return (
    window.sessionStorage.getItem("statisticsLocalSessionRef") ||
    statisticsLocalSessionRef ||
    ""
  );
}

export function setLocalSessionRef(sessionRef: string) {
  if (sessionRef) {
    statisticsLocalSessionRef = sessionRef;
    window.sessionStorage.setItem("statisticsLocalSessionRef", sessionRef);
  }
}