wayfarer/index.js

const assert = require('assert')
const sliced = require('sliced')
const trie = require('./trie')

module.exports = Wayfarer

// create a router
// str -> obj
function Wayfarer (dft) {
  if (!(this instanceof Wayfarer)) return new Wayfarer(dft)

  const _default = (dft || '').replace(/^\//, '')
  const _trie = trie()

  emit._trie = _trie
  emit.emit = emit
  emit.on = on
  emit._wayfarer = true

  return emit

  // define a route
  // (str, fn) -> obj
  function on (route, cb) {
    assert.equal(typeof route, 'string')
    assert.equal(typeof cb, 'function')

    route = route || '/'

    if (cb && cb._wayfarer && cb._trie) {
      _trie.mount(route, cb._trie.trie)
    } else {
      const node = _trie.create(route)
      node.cb = cb
    }

    return emit
  }

  // match and call a route
  // (str, obj?) -> null
  function emit (route) {
    assert.notEqual(route, undefined, "'route' must be defined")
    const args = sliced(arguments)

    const node = _trie.match(route)
    if (node && node.cb) {
      args[0] = node.params
      return node.cb.apply(null, args)
    }

    const dft = _trie.match(_default)
    if (dft && dft.cb) {
      args[0] = dft.params
      return dft.cb.apply(null, args)
    }

    throw new Error("route '" + route + "' did not match")
  }
}