function asString(val) {
  return typeof val === 'string' && val
}

function linkDest(val) {
  return val ? asString(val) || asString(val.link) : null
}

function defalsify(val) {
  return val === 'false' ? false : val
}

module.exports = function (sbot, id, cb) {
  var aboutByFeed = {}

  let values = module.exports.allAbouts[id]

  for (var key in values) {
    for (var author in values[key]) {
      var feedAbout = aboutByFeed[author] || (aboutByFeed[author] = {})

      var v = values[key][author][0]

      if (!v) break;

      if (key == 'name') feedAbout.name = v.replace(/^@?/, '@')
      if (key == 'image') feedAbout.image = linkDest(v)
      if (key == 'description') feedAbout.description = v
      if (key == 'publicWebHosting' && author === id) feedAbout.publicWebHosting = defalsify(v)
    }
  }

  // Use whatever properties have the most counts.
  // Usually we would want to handle renames for dead feeds and such,
  // but for ssb-viewer it is mostly public/archival content anyway,
  // so we'll let the popular name stand.
  // Except: prefer the feed's own choices slightly
  var propValueCounts = {/* prop: {value: count} */}
  var topValues = {/* prop: value */}
  var topValueCounts = {/* prop: count */}
  var about = {}
  // bias the feed's own choice by 1
  aboutByFeed._author = aboutByFeed[id] || {}
  for (var feed in aboutByFeed) {
    var feedAbout = aboutByFeed[feed]
    for (var prop in feedAbout) {
      var value = feedAbout[prop]
      var valueCounts = propValueCounts[prop] || (propValueCounts[prop] = {})
      var count = (valueCounts[value] || 0) + 1
      valueCounts[value] = count
      if (count > (topValueCounts[prop] || 0)) {
        topValueCounts[prop] = count
        topValues[prop] = value
      }
    }
  }
  if (!topValues.name) topValues.name = String(id).substr(0, 10) + '…'
  cb(null, topValues)
}