/**
 * This controller is in charge of all the actions relating to calling the youtube API 
 * 
 * @module YoutubeController
 * @category Backend
 * @subcategory Controllers
 */
const axios = require("axios");
var { google } = require("googleapis");
var OAuth2 = google.auth.OAuth2;
const { GOOGLE_CONFIG } = require("../passportConfigs/passportConfigs.js");
const NodeCache = require("node-cache");
const myCache = new NodeCache({ stdTTL: 60 * 60, checkperiod: 120 });

/**
 * Get the current users youtube channel from his access tokens
 * @param {*} accessToken our currentr access token
 * @param {*} refreshToken our current refresh token
 */
exports.getYoutubeChannelFromGoogle = async function (
  accessToken,
  refreshToken
) {
  //****************Getting user's youtube channels **************** */
  var oauth2Client = new OAuth2(
    GOOGLE_CONFIG.clientID,
    GOOGLE_CONFIG.clientSecret,
    "/auth/google/callback"
  );
  oauth2Client.credentials = {
    access_token: accessToken,
    refresh_token: refreshToken,
  };
  try {
    var service = google.youtube("v3");
    var response = await service.channels.list({
      auth: oauth2Client,
      part: "snippet,contentDetails,statistics",
      mine: true,
    });
  } catch (err) {
    console.log("The API returned an error: " + err);
    return;
  }

  var channels = response.data.items;
  if (channels && channels.length == 0) {
    console.log("No channel found.");
  }
  return channels;
};

/**
 * Returns the live video id of the requested channel id, tried to call it from cache if possible
 * @param {*} req.body.channelId id of the channle to find live video for
 */
exports.getLiveVideoId = async function (req, res) {
  const channelId = req.body.channelId;
  if (channelId == undefined) {
    send("/stream/no_channel_id");
  }
  let videoId = myCache.get(channelId);
  if (videoId === undefined) {
    const result = await axios({
      method: "GET",
      url: `https://www.googleapis.com/youtube/v3/search?part=snippet&channelId=${channelId}&eventType=live&type=video&key=${GOOGLE_CONFIG.apiKey}`,
    })
      .catch((e) => {
        console.log("error on getting video id");
      })
      .then((result) => {
        if (
          result &&
          result.data &&
          result.data.items &&
          result.data.items.length > 0
        ) {
          videoId = result.data.items[0].id.videoId;
          const success = myCache.set(channelId, videoId);
          res.send(videoId);
          return;
        }
        res.send("/stream/no_stream");
      });
  } else {
    res.send(videoId);
  }
};