import { SignalInstance } from '../types/signal.types';
import { supportsLocalStorage } from './cache.helper';
import { v4 as uuid } from 'uuid';
import { getDateString } from './date.helper';
import { CLIENT_CACHE_KEY } from '../constants/constants';

type CachedClientObj = {
  clientId: string;
  clientCreated: string;
};

const getCachedClientInfo = () => {
  const clientCache = localStorage.getItem(CLIENT_CACHE_KEY);

  if (clientCache) {
    try {
      return JSON.parse(clientCache) as CachedClientObj;
    } catch (e) {
      // do nothing
    }
  }

  return null;
};

export const getClientInfo = (instance: SignalInstance) => {
  if (instance.deviceId || !instance.clientUserAgent) {
    return {
      clientId: undefined,
      clientCreated: null,
    };
  }

  if (!supportsLocalStorage()) {
    throw new Error('Local storage is not supported. Cannot create client id');
  }

  const cachedClientObj = getCachedClientInfo();
  if (cachedClientObj && cachedClientObj.clientId && cachedClientObj.clientCreated) {
    return {
      clientId: cachedClientObj.clientId,
      clientCreated: cachedClientObj.clientCreated,
    };
  }

  const newClientInfo = {
    clientId: uuid(),
    clientCreated: getDateString(),
  };

  localStorage.setItem(CLIENT_CACHE_KEY, JSON.stringify(newClientInfo));

  return newClientInfo;
};