parse the parts from a known URL

location.js

// the point of this is to create a similar api to window.location from a known URL

// usage
/*
  var parts = new Location('http://twitter.com/path/to/?q=foo=bar&baz=1#hashbang');
  console.log(parts);
*/

function Location(url) {
  if (url.match(/^\/\//)) {
    url = 'http:' + url;
  } else if (!url.match(/^[a-z]+:\/\//)) {
    url = 'http://' + url;
  }
  var m = url.match(/^([a-z]+:)\/\/([\w\-\.]+)(\:\d+)?(.+)?/);
  this.href = url;
  this.protocol = m[1];
  this.hostname = m[2];
  this.host = m[2] + (m[3] || '');
  this.port = m[3] ? m[3].slice(1) : m[1] === 'https:' ? '443' : '80';

  var ext = m[2].match(/\.(\w+)$/);
  if (ext) {
    this.extension = ext[1];
  } else {
    this.ext = '';
  }

  if (!m[4]) {
    this.hash = '';
    this.search = '';
    this.pathname = '/';
  } else {

    if (!m[4].match(/^\//)) {
      m[4] = '/' + m[4];
    }
    var query = m[4].split('?');
    var hash = m[4].split('#');

    this.pathname = query[0];
    if (!((/\/$/).test(this.pathname))) {
      this.pathname = this.pathname + '/';
    }

    this.search = query.length > 1 ? '?' + (function() {
      query.shift();
      return query.join('').replace(/#.+$/, '');
    }()) : '';

    this.hash = hash.length > 1 ? '#' + hash[1] : '';
  }
}