const db = require('server/models');
const {
  getInformationFromValues,
  getZScore,
  getFastPValue,
  getWeight,
} = require('server/models/utils/trendingAnalysis');

module.exports = async () => {
  const claims = await db.Trending.getTrendingClaims();
  const claimViews = await db.Views.getUniqueViews();

  if(claimViews.length <= 1) {
    return;
  }

  const time = Date.now();

  // Must create statistical analytics before we can process zScores, etc
  const viewsNumArray = claimViews.map((claimViewsEntry) => claimViewsEntry.views);
  const {
    mean,
    standardDeviation,
  } = getInformationFromValues(viewsNumArray);

  for(let i = 0; i < claimViews.length; i++) {
    let claimViewsEntry = claimViews[i];

    const {
      isChannel,
      claimId,
      publisherId,
    } = claimViewsEntry;

    const zScore = getZScore(claimViewsEntry.views, mean, standardDeviation);
    const pValue = getFastPValue(zScore);
    const weight = getWeight(zScore, pValue);

    const trendingData = {
      time,
      isChannel: claimViewsEntry.isChannel,
      claimId: claimViewsEntry.claimId,
      publisherId: claimViewsEntry.publisherId,
      intervalViews: claimViewsEntry.views,
      weight,
      zScore,
      pValue,
    };

    db.Trending.create(trendingData);
  }
}