'use strict';

var constants = require('./constants');
var formatUrl = require('./format');
var getOptions = require('./options');
var objUtils = require('./util/object');
var parseUrl = require('./parse');
var relateUrl = require('./relate');

function RelateUrl(from, options) {
  this.options = getOptions(options, {
    defaultPorts: { ftp: 21, http: 80, https: 443 },
    directoryIndexes: ['index.html'],
    ignore_www: false,
    output: RelateUrl.SHORTEST,
    rejectedSchemes: ['data', 'javascript', 'mailto'],
    removeAuth: false,
    removeDirectoryIndexes: true,
    removeEmptyQueries: false,
    removeRootTrailingSlash: true,
    schemeRelative: true,
    site: undefined,
    slashesDenoteHost: true,
  });

  this.from = parseUrl.from(from, this.options, null);
}

/*
	Usage: instance=new RelateUrl(); instance.relate();
*/
RelateUrl.prototype.relate = function (from, to, options) {
  // relate(to,options)
  if (objUtils.isPlainObject(to)) {
    options = to;
    to = from;
    from = null;
  }
  // relate(to)
  else if (!to) {
    to = from;
    from = null;
  }

  options = getOptions(options, this.options);
  from = from || options.site;
  from = parseUrl.from(from, options, this.from);

  if (!from || !from.href) {
    throw new Error('from value not defined.');
  } else if (from.extra.hrefInfo.minimumPathOnly) {
    throw new Error('from value supplied is not absolute: ' + from.href);
  }

  to = parseUrl.to(to, options);

  if (to.valid === false) return to.href;

  to = relateUrl(from, to, options);
  to = formatUrl(to, options);

  return to;
};

/*
	Usage: RelateUrl.relate();
*/
RelateUrl.relate = function (from, to, options) {
  return new RelateUrl().relate(from, to, options);
};

// Make constants accessible from API
objUtils.shallowMerge(RelateUrl, constants);

module.exports = RelateUrl;