function filterProposals()

in index.js [661:699]

• 30 lines of code
• 5 McCabe index (conditional complexity)

function filterProposals () {
  var filterElement = document.querySelector('#search-filter')
  var filter = filterElement.value

  var clearButton = document.querySelector('#clear-button')
  if (filter.length === 0) {
    clearButton.classList.add('hidden')
  } else {
    clearButton.classList.remove('hidden')
  }

  var matchingSets = [proposals.concat()]

  // Comma-separated lists of proposal IDs are treated as an "or" search.
  if (filter.match(/(SE-\d\d\d\d)($|((,SE-\d\d\d\d)+))/i)) {
    var proposalIDs = filter.split(',').map(function (id) {
      return id.toUpperCase()
    })

    matchingSets[0] = matchingSets[0].filter(function (proposal) {
      return proposalIDs.indexOf(proposal.id) !== -1
    })
  } else if (filter.trim().length !== 0) {
    // The search input treats words as order-independent.
    matchingSets = filter.split(/\s/)
      .filter(function (s) { return s.length > 0 })
      .map(function (part) { return _searchProposals(part) })
  }

  var intersection = matchingSets.reduce(function (intersection, candidates) {
    return intersection.filter(function (alreadyIncluded) { return candidates.indexOf(alreadyIncluded) !== -1 })
  }, matchingSets[0] || [])

  _applyFilter(intersection)
  _updateURIFragment()

  determineNumberOfProposals(intersection)
  updateFilterStatus()
}