// calculate a virtual InnerSource score from stars, watches, commits, and issues
function calculateScore(repo) {
// initial score is 50 to give active repos with low GitHub KPIs (forks, watchers, stars) a better starting point
// weighting: forks and watches count most, then stars, add some little score for open issues, too
iScore += repo.forks_count * 5;
iScore += (repo.subscribers_count ? repo.subscribers_count : 0);
iScore += repo.stargazers_count / 3;
iScore += repo.open_issues_count / 5;
// updated in last 3 months: adds a bonus multiplier between 0..1 to overall score (1 = updated today, 0 = updated more than 100 days ago)
let iDaysSinceLastUpdate = (new Date().getTime() - new Date(repo.updated_at).getTime()) / 1000 / 86400;
iScore = iScore * ((1 + (100 - Math.min(iDaysSinceLastUpdate, 100))) / 100);
// evaluate participation stats for the previous 3 months
repo._InnerSourceMetadata = repo._InnerSourceMetadata || {};
if (repo._InnerSourceMetadata.participation) {
// average commits: adds a bonus multiplier between 0..1 to overall score (1 = >10 commits per week, 0 = less than 3 commits per week)
let iAverageCommitsPerWeek = repo._InnerSourceMetadata.participation.slice(-13).reduce((a, b) => a + b) / 13;
iScore = iScore * ((1 + (Math.min(Math.max(iAverageCommitsPerWeek - 3, 0), 7))) / 7);
// all repositories updated in the previous year will receive a boost of maximum 1000 declining by days since last update
let iBoost = (1000 - Math.min(iDaysSinceLastUpdate, 365) * 2.74);
// gradually scale down boost according to repository creation date to mix with "real" engagement stats
let iDaysSinceCreation = (new Date().getTime() - new Date(repo.created_at).getTime()) / 1000 / 86400;
iBoost *= (365 - Math.min(iDaysSinceCreation, 365)) / 365;
// give projects with a meaningful description a static boost of 50
iScore += (repo.description?.length > 30 || repo._InnerSourceMetadata.motivation?.length > 30 ? 50 : 0);
// give projects with contribution guidelines (CONTRIBUTING.md) file a static boost of 100
iScore += (repo._InnerSourceMetadata.guidelines ? 100 : 0);
// build in a logarithmic scale for very active projects (open ended but stabilizing around 5000)
iScore = 3000 + Math.log(iScore) * 100;
// final score is a rounded value starting from 0 (subtract the initial value)
iScore = Math.round(iScore - 50);
// add score to metadata on the fly
repo._InnerSourceMetadata.score = iScore;