'use strict';

const { settings } = require('./settings');
const { getUpstreams } = require('./config');
const {
  getLastProbeAt,
  rankedUpstreams,
  describeUpstream,
  totalConnectionCapacity,
} = require('./upstream-pool');

function healthPayload() {
  const upstreams = getUpstreams();
  const ranked = rankedUpstreams();
  const selected = ranked.find((entry) => !entry.busy) || ranked[0] || null;

  return {
    ok: upstreams.some((upstream) => upstream.state.healthy),
    configFile: settings.configFile,
    probeIntervalSec: settings.probeIntervalSec,
    lastProbeAt: getLastProbeAt(),
    maxConnections: totalConnectionCapacity(),
    selected: selected ? describeUpstream(selected.upstream) : null,
    upstreams: upstreams.map(describeUpstream),
  };
}

module.exports = { healthPayload };