/*!
 * URI.js - Mutating URLs
 *
 * Version: 1.11.2
 *
 * Author: Rodney Rehm
 * Web: http://medialize.github.com/URI.js/
 *
 * Licensed under
 *   MIT License http://www.opensource.org/licenses/mit-license
 *   GPL v3 http://opensource.org/licenses/GPL-3.0 
 *
 */
(function (root, factory) {
    // https://github.com/umdjs/umd/blob/master/returnExports.js
    if (typeof exports === 'object') {
        // Node
        module.exports = factory(require('./punycode'), require('./IPv6'), require('./SecondLevelDomains'));
    } else if (typeof define === 'function' && define.amd) {
        // AMD. Register as an anonymous module.
        define(['./punycode', './IPv6', './SecondLevelDomains'], factory);
    } else {
        // Browser globals (root is window)
        root.URI = factory(root.punycode, root.IPv6, root.SecondLevelDomains, root);
    }
}(this, function (punycode, IPv6, SLD, root) {
"use strict";

// save current URI variable, if any
var _URI = root && root.URI;

function URI(url, base) {
    // Allow instantiation without the 'new' keyword
    if (!(this instanceof URI)) {
        return new URI(url, base);
    }

    if (url === undefined) {
        if (typeof location !== 'undefined') {
            url = location.href + "";
        } else {
            url = "";
        }
    }

    this.href(url);

    // resolve to base according to http://dvcs.w3.org/hg/url/raw-file/tip/Overview.html#constructor
    if (base !== undefined) {
        return this.absoluteTo(base);
    }

    return this;
};

var p = URI.prototype;
var hasOwn = Object.prototype.hasOwnProperty;

function escapeRegEx(string) {
    // https://github.com/medialize/URI.js/commit/85ac21783c11f8ccab06106dba9735a31a86924d#commitcomment-821963
    return string.replace(/([.*+?^=!:${}()|[\]\/\\])/g, '\\$1');
}

function getType(value) {
    // IE8 doesn't return [Object Undefined] but [Object Object] for undefined value
    if (value === undefined) {
        return 'Undefined';
    }

    return String(Object.prototype.toString.call(value)).slice(8, -1);
}

function isArray(obj) {
    return getType(obj) === "Array";
}

function filterArrayValues(data, value) {
    var lookup = {};
    var i, length;

    if (isArray(value)) {
        for (i = 0, length = value.length; i < length; i++) {
            lookup[value[i]] = true;
        }
    } else {
        lookup[value] = true;
    }

    for (i = 0, length = data.length; i < length; i++) {
        if (lookup[data[i]] !== undefined) {
            data.splice(i, 1);
            length--;
            i--;
        }
    }

    return data;
}

function arrayContains(list, value) {
    var i, length;
    
    // value may be string, number, array, regexp
    if (isArray(value)) {
        // Note: this can be optimized to O(n) (instead of current O(m * n))
        for (i = 0, length = value.length; i < length; i++) {
            if (!arrayContains(list, value[i])) {
                return false;
            }
        }
        
        return true;
    }
    
    var _type = getType(value);
    for (i = 0, length = list.length; i < length; i++) {
        if (_type === 'RegExp') {
            if (typeof list[i] === 'string' && list[i].match(value)) {
                return true;
            }
        } else if (list[i] === value) {
            return true;
        }
    }

    return false;
}

function arraysEqual(one, two) {
    if (!isArray(one) || !isArray(two)) {
        return false;
    }
    
    // arrays can't be equal if they have different amount of content
    if (one.length !== two.length) {
        return false;
    }

    one.sort();
    two.sort();

    for (var i = 0, l = one.length; i < l; i++) {
        if (one[i] !== two[i]) {
            return false;
        }
    }
    
    return true;
}

URI._parts = function() {
    return {
        protocol: null,
        username: null,
        password: null,
        hostname: null,
        urn: null,
        port: null,
        path: null,
        query: null,
        fragment: null,
        // state
        duplicateQueryParameters: URI.duplicateQueryParameters,
        escapeQuerySpace: URI.escapeQuerySpace
    };
};
// state: allow duplicate query parameters (a=1&a=1)
URI.duplicateQueryParameters = false;
// state: replaces + with %20 (space in query strings)
URI.escapeQuerySpace = true;
// static properties
URI.protocol_expression = /^[a-z][a-z0-9-+-]*$/i;
URI.idn_expression = /[^a-z0-9\.-]/i;
URI.punycode_expression = /(xn--)/i;
// well, 333.444.555.666 matches, but it sure ain't no IPv4 - do we care?
URI.ip4_expression = /^\d{1,3}\.\d{1,3}\.\d{1,3}\.\d{1,3}$/;
// credits to Rich Brown
// source: http://forums.intermapper.com/viewtopic.php?p=1096#1096
// specification: http://www.ietf.org/rfc/rfc4291.txt
URI.ip6_expression = /^\s*((([0-9A-Fa-f]{1,4}:){7}([0-9A-Fa-f]{1,4}|:))|(([0-9A-Fa-f]{1,4}:){6}(:[0-9A-Fa-f]{1,4}|((25[0-5]|2[0-4]\d|1\d\d|[1-9]?\d)(\.(25[0-5]|2[0-4]\d|1\d\d|[1-9]?\d)){3})|:))|(([0-9A-Fa-f]{1,4}:){5}(((:[0-9A-Fa-f]{1,4}){1,2})|:((25[0-5]|2[0-4]\d|1\d\d|[1-9]?\d)(\.(25[0-5]|2[0-4]\d|1\d\d|[1-9]?\d)){3})|:))|(([0-9A-Fa-f]{1,4}:){4}(((:[0-9A-Fa-f]{1,4}){1,3})|((:[0-9A-Fa-f]{1,4})?:((25[0-5]|2[0-4]\d|1\d\d|[1-9]?\d)(\.(25[0-5]|2[0-4]\d|1\d\d|[1-9]?\d)){3}))|:))|(([0-9A-Fa-f]{1,4}:){3}(((:[0-9A-Fa-f]{1,4}){1,4})|((:[0-9A-Fa-f]{1,4}){0,2}:((25[0-5]|2[0-4]\d|1\d\d|[1-9]?\d)(\.(25[0-5]|2[0-4]\d|1\d\d|[1-9]?\d)){3}))|:))|(([0-9A-Fa-f]{1,4}:){2}(((:[0-9A-Fa-f]{1,4}){1,5})|((:[0-9A-Fa-f]{1,4}){0,3}:((25[0-5]|2[0-4]\d|1\d\d|[1-9]?\d)(\.(25[0-5]|2[0-4]\d|1\d\d|[1-9]?\d)){3}))|:))|(([0-9A-Fa-f]{1,4}:){1}(((:[0-9A-Fa-f]{1,4}){1,6})|((:[0-9A-Fa-f]{1,4}){0,4}:((25[0-5]|2[0-4]\d|1\d\d|[1-9]?\d)(\.(25[0-5]|2[0-4]\d|1\d\d|[1-9]?\d)){3}))|:))|(:(((:[0-9A-Fa-f]{1,4}){1,7})|((:[0-9A-Fa-f]{1,4}){0,5}:((25[0-5]|2[0-4]\d|1\d\d|[1-9]?\d)(\.(25[0-5]|2[0-4]\d|1\d\d|[1-9]?\d)){3}))|:)))(%.+)?\s*$/;
// gruber revised expression - http://rodneyrehm.de/t/url-regex.html
URI.find_uri_expression = /\b((?:[a-z][\w-]+:(?:\/{1,3}|[a-z0-9%])|www\d{0,3}[.]|[a-z0-9.\-]+[.][a-z]{2,4}\/)(?:[^\s()<>]+|\(([^\s()<>]+|(\([^\s()<>]+\)))*\))+(?:\(([^\s()<>]+|(\([^\s()<>]+\)))*\)|[^\s`!()\[\]{};:'".,<>?«»“”‘’]))/ig;
// http://www.iana.org/assignments/uri-schemes.html
// http://en.wikipedia.org/wiki/List_of_TCP_and_UDP_port_numbers#Well-known_ports
URI.defaultPorts = {
    http: "80",
    https: "443",
    ftp: "21",
    gopher: "70",
    ws: "80",
    wss: "443"
};
// allowed hostname characters according to RFC 3986
// ALPHA DIGIT "-" "." "_" "~" "!" "$" "&" "'" "(" ")" "*" "+" "," ";" "=" %encoded
// I've never seen a (non-IDN) hostname other than: ALPHA DIGIT . -
URI.invalid_hostname_characters = /[^a-zA-Z0-9\.-]/;
// map DOM Elements to their URI attribute
URI.domAttributes = {
    'a': 'href',
    'blockquote': 'cite',
    'link': 'href',
    'base': 'href',
    'script': 'src',
    'form': 'action',
    'img': 'src',
    'area': 'href',
    'iframe': 'src',
    'embed': 'src',
    'source': 'src',
    'track': 'src',
    'input': 'src' // but only if type="image"
};
URI.getDomAttribute = function(node) {
    if (!node || !node.nodeName) {
        return undefined;
    }
    
    var nodeName = node.nodeName.toLowerCase();
    // <input> should only expose src for type="image"
    if (nodeName === 'input' && node.type !== 'image') {
        return undefined;
    }
    
    return URI.domAttributes[nodeName];
};

function escapeForDumbFirefox36(value) {
    // https://github.com/medialize/URI.js/issues/91
    return escape(value);
}

// encoding / decoding according to RFC3986
function strictEncodeURIComponent(string) {
    // see https://developer.mozilla.org/en-US/docs/JavaScript/Reference/Global_Objects/encodeURIComponent
    return encodeURIComponent(string)
        .replace(/[!'()*]/g, escapeForDumbFirefox36)
        .replace(/\*/g, "%2A");
}
URI.encode = strictEncodeURIComponent;
URI.decode = decodeURIComponent;
URI.iso8859 = function() {
    URI.encode = escape;
    URI.decode = unescape;
};
URI.unicode = function() {
    URI.encode = strictEncodeURIComponent;
    URI.decode = decodeURIComponent;
};
URI.characters = {
    pathname: {
        encode: {
            // RFC3986 2.1: For consistency, URI producers and normalizers should
            // use uppercase hexadecimal digits for all percent-encodings.
            expression: /%(24|26|2B|2C|3B|3D|3A|40)/ig,
            map: {
                // -._~!'()*
                "%24": "$",
                "%26": "&",
                "%2B": "+",
                "%2C": ",",
                "%3B": ";",
                "%3D": "=",
                "%3A": ":",
                "%40": "@"
            }
        },
        decode: {
            expression: /[\/\?#]/g,
            map: {
                "/": "%2F",
                "?": "%3F",
                "#": "%23"
            }
        }
    },
    reserved: {
        encode: {
            // RFC3986 2.1: For consistency, URI producers and normalizers should
            // use uppercase hexadecimal digits for all percent-encodings.
            expression: /%(21|23|24|26|27|28|29|2A|2B|2C|2F|3A|3B|3D|3F|40|5B|5D)/ig,
            map: {
                // gen-delims
                "%3A": ":",
                "%2F": "/",
                "%3F": "?",
                "%23": "#",
                "%5B": "[",
                "%5D": "]",
                "%40": "@",
                // sub-delims
                "%21": "!",
                "%24": "$",
                "%26": "&",
                "%27": "'",
                "%28": "(",
                "%29": ")",
                "%2A": "*",
                "%2B": "+",
                "%2C": ",",
                "%3B": ";",
                "%3D": "="
            }
        }
    }
};
URI.encodeQuery = function(string, escapeQuerySpace) {
    var escaped = URI.encode(string + "");
    return escapeQuerySpace ? escaped.replace(/%20/g, '+') : escaped;
};
URI.decodeQuery = function(string, escapeQuerySpace) {
    string += "";
    try {
        return URI.decode(escapeQuerySpace ? string.replace(/\+/g, '%20') : string);
    } catch(e) {
        // we're not going to mess with weird encodings,
        // give up and return the undecoded original string
        // see https://github.com/medialize/URI.js/issues/87
        // see https://github.com/medialize/URI.js/issues/92
        return string;
    }
};
URI.recodePath = function(string) {
    var segments = (string + "").split('/');
    for (var i = 0, length = segments.length; i < length; i++) {
        segments[i] = URI.encodePathSegment(URI.decode(segments[i]));
    }

    return segments.join('/');
};
URI.decodePath = function(string) {
    var segments = (string + "").split('/');
    for (var i = 0, length = segments.length; i < length; i++) {
        segments[i] = URI.decodePathSegment(segments[i]);
    }

    return segments.join('/');
};
// generate encode/decode path functions
var _parts = {'encode':'encode', 'decode':'decode'};
var _part;
var generateAccessor = function(_group, _part) {
    return function(string) {
        return URI[_part](string + "").replace(URI.characters[_group][_part].expression, function(c) {
            return URI.characters[_group][_part].map[c];
        });
    };
};

for (_part in _parts) {
    URI[_part + "PathSegment"] = generateAccessor("pathname", _parts[_part]);
}

URI.encodeReserved = generateAccessor("reserved", "encode");

URI.parse = function(string, parts) {
    var pos;
    if (!parts) {
        parts = {};
    }
    // [protocol"://"[username[":"password]"@"]hostname[":"port]"/"?][path]["?"querystring]["#"fragment]

    // extract fragment
    pos = string.indexOf('#');
    if (pos > -1) {
        // escaping?
        parts.fragment = string.substring(pos + 1) || null;
        string = string.substring(0, pos);
    }

    // extract query
    pos = string.indexOf('?');
    if (pos > -1) {
        // escaping?
        parts.query = string.substring(pos + 1) || null;
        string = string.substring(0, pos);
    }

    // extract protocol
    if (string.substring(0, 2) === '//') {
        // relative-scheme
        parts.protocol = null;
        string = string.substring(2);
        // extract "user:pass@host:port"
        string = URI.parseAuthority(string, parts);
    } else {
        pos = string.indexOf(':');
        if (pos > -1) {
            parts.protocol = string.substring(0, pos) || null;
            if (parts.protocol && !parts.protocol.match(URI.protocol_expression)) {
                // : may be within the path
                parts.protocol = undefined;
            } else if (parts.protocol === 'file') {
                // the file scheme: does not contain an authority
                string = string.substring(pos + 3);
            } else if (string.substring(pos + 1, pos + 3) === '//') {
                string = string.substring(pos + 3);

                // extract "user:pass@host:port"
                string = URI.parseAuthority(string, parts);
            } else {
                string = string.substring(pos + 1);
                parts.urn = true;
            }
        }
    }

    // what's left must be the path
    parts.path = string;

    // and we're done
    return parts;
};
URI.parseHost = function(string, parts) {
    // extract host:port
    var pos = string.indexOf('/');
    var bracketPos;
    var t;

    if (pos === -1) {
        pos = string.length;
    }

    if (string.charAt(0) === "[") {
        // IPv6 host - http://tools.ietf.org/html/draft-ietf-6man-text-addr-representation-04#section-6
        // I claim most client software breaks on IPv6 anyways. To simplify things, URI only accepts
        // IPv6+port in the format [2001:db8::1]:80 (for the time being)
        bracketPos = string.indexOf(']');
        parts.hostname = string.substring(1, bracketPos) || null;
        parts.port = string.substring(bracketPos+2, pos) || null;
    } else if (string.indexOf(':') !== string.lastIndexOf(':')) {
        // IPv6 host contains multiple colons - but no port
        // this notation is actually not allowed by RFC 3986, but we're a liberal parser
        parts.hostname = string.substring(0, pos) || null;
        parts.port = null;
    } else {
        t = string.substring(0, pos).split(':');
        parts.hostname = t[0] || null;
        parts.port = t[1] || null;
    }

    if (parts.hostname && string.substring(pos).charAt(0) !== '/') {
        pos++;
        string = "/" + string;
    }

    return string.substring(pos) || '/';
};
URI.parseAuthority = function(string, parts) {
    string = URI.parseUserinfo(string, parts);
    return URI.parseHost(string, parts);
};
URI.parseUserinfo = function(string, parts) {
    // extract username:password
    var firstSlash = string.indexOf('/');
    var pos = firstSlash > -1 
        ? string.lastIndexOf('@', firstSlash) 
        : string.indexOf('@');
    var t;

    // authority@ must come before /path
    if (pos > -1 && (firstSlash === -1 || pos < firstSlash)) {
        t = string.substring(0, pos).split(':');
        parts.username = t[0] ? URI.decode(t[0]) : null;
        t.shift();
        parts.password = t[0] ? URI.decode(t.join(':')) : null;
        string = string.substring(pos + 1);
    } else {
        parts.username = null;
        parts.password = null;
    }

    return string;
};
URI.parseQuery = function(string, escapeQuerySpace) {
    if (!string) {
        return {};
    }

    // throw out the funky business - "?"[name"="value"&"]+
    string = string.replace(/&+/g, '&').replace(/^\?*&*|&+$/g, '');

    if (!string) {
        return {};
    }

    var items = {};
    var splits = string.split('&');
    var length = splits.length;
    var v, name, value;

    for (var i = 0; i < length; i++) {
        v = splits[i].split('=');
        name = URI.decodeQuery(v.shift(), escapeQuerySpace);
        // no "=" is null according to http://dvcs.w3.org/hg/url/raw-file/tip/Overview.html#collect-url-parameters
        value = v.length ? URI.decodeQuery(v.join('='), escapeQuerySpace) : null;

        if (items[name]) {
            if (typeof items[name] === "string") {
                items[name] = [items[name]];
            }

            items[name].push(value);
        } else {
            items[name] = value;
        }
    }

    return items;
};

URI.build = function(parts) {
    var t = "";

    if (parts.protocol) {
        t += parts.protocol + ":";
    }

    if (!parts.urn && (t || parts.hostname)) {
        t += '//';
    }

    t += (URI.buildAuthority(parts) || '');

    if (typeof parts.path === "string") {
        if (parts.path.charAt(0) !== '/' && typeof parts.hostname === "string") {
            t += '/';
        }

        t += parts.path;
    }

    if (typeof parts.query === "string" && parts.query) {
        t += '?' + parts.query;
    }

    if (typeof parts.fragment === "string" && parts.fragment) {
        t += '#' + parts.fragment;
    }
    return t;
};
URI.buildHost = function(parts) {
    var t = "";

    if (!parts.hostname) {
        return "";
    } else if (URI.ip6_expression.test(parts.hostname)) {
        if (parts.port) {
            t += "[" + parts.hostname + "]:" + parts.port;
        } else {
            // don't know if we should always wrap IPv6 in []
            // the RFC explicitly says SHOULD, not MUST.
            t += parts.hostname;
        }
    } else {
        t += parts.hostname;
        if (parts.port) {
            t += ':' + parts.port;
        }
    }

    return t;
};
URI.buildAuthority = function(parts) {
    return URI.buildUserinfo(parts) + URI.buildHost(parts);
};
URI.buildUserinfo = function(parts) {
    var t = "";

    if (parts.username) {
        t += URI.encode(parts.username);

        if (parts.password) {
            t += ':' + URI.encode(parts.password);
        }

        t += "@";
    }

    return t;
};
URI.buildQuery = function(data, duplicateQueryParameters, escapeQuerySpace) {
    // according to http://tools.ietf.org/html/rfc3986 or http://labs.apache.org/webarch/uri/rfc/rfc3986.html
    // being »-._~!$&'()*+,;=:@/?« %HEX and alnum are allowed
    // the RFC explicitly states ?/foo being a valid use case, no mention of parameter syntax!
    // URI.js treats the query string as being application/x-www-form-urlencoded
    // see http://www.w3.org/TR/REC-html40/interact/forms.html#form-content-type

    var t = "";
    var unique, key, i, length;
    for (key in data) {
        if (hasOwn.call(data, key) && key) {
            if (isArray(data[key])) {
                unique = {};
                for (i = 0, length = data[key].length; i < length; i++) {
                    if (data[key][i] !== undefined && unique[data[key][i] + ""] === undefined) {
                        t += "&" + URI.buildQueryParameter(key, data[key][i], escapeQuerySpace);
                        if (duplicateQueryParameters !== true) {
                            unique[data[key][i] + ""] = true;
                        }
                    }
                }
            } else if (data[key] !== undefined) {
                t += '&' + URI.buildQueryParameter(key, data[key], escapeQuerySpace);
            }
        }
    }

    return t.substring(1);
};
URI.buildQueryParameter = function(name, value, escapeQuerySpace) {
    // http://www.w3.org/TR/REC-html40/interact/forms.html#form-content-type -- application/x-www-form-urlencoded
    // don't append "=" for null values, according to http://dvcs.w3.org/hg/url/raw-file/tip/Overview.html#url-parameter-serialization
    return URI.encodeQuery(name, escapeQuerySpace) + (value !== null ? "=" + URI.encodeQuery(value, escapeQuerySpace) : "");
};

URI.addQuery = function(data, name, value) {
    if (typeof name === "object") {
        for (var key in name) {
            if (hasOwn.call(name, key)) {
                URI.addQuery(data, key, name[key]);
            }
        }
    } else if (typeof name === "string") {
        if (data[name] === undefined) {
            data[name] = value;
            return;
        } else if (typeof data[name] === "string") {
            data[name] = [data[name]];
        }

        if (!isArray(value)) {
            value = [value];
        }

        data[name] = data[name].concat(value);
    } else {
        throw new TypeError("URI.addQuery() accepts an object, string as the name parameter");
    }
};
URI.removeQuery = function(data, name, value) {
    var i, length, key;
    
    if (isArray(name)) {
        for (i = 0, length = name.length; i < length; i++) {
            data[name[i]] = undefined;
        }
    } else if (typeof name === "object") {
        for (key in name) {
            if (hasOwn.call(name, key)) {
                URI.removeQuery(data, key, name[key]);
            }
        }
    } else if (typeof name === "string") {
        if (value !== undefined) {
            if (data[name] === value) {
                data[name] = undefined;
            } else if (isArray(data[name])) {
                data[name] = filterArrayValues(data[name], value);
            }
        } else {
            data[name] = undefined;
        }
    } else {
        throw new TypeError("URI.addQuery() accepts an object, string as the first parameter");
    }
};
URI.hasQuery = function(data, name, value, withinArray) {
    if (typeof name === "object") {
        for (var key in name) {
            if (hasOwn.call(name, key)) {
                if (!URI.hasQuery(data, key, name[key])) {
                    return false;
                }
            }
        }
        
        return true;
    } else if (typeof name !== "string") {
        throw new TypeError("URI.hasQuery() accepts an object, string as the name parameter");
    }

    switch (getType(value)) {
        case 'Undefined':
            // true if exists (but may be empty)
            return name in data; // data[name] !== undefined;

        case 'Boolean':
            // true if exists and non-empty
            var _booly = Boolean(isArray(data[name]) ? data[name].length : data[name]);
            return value === _booly;

        case 'Function':
            // allow complex comparison
            return !!value(data[name], name, data);

        case 'Array':
            if (!isArray(data[name])) {
                return false;
            }

            var op = withinArray ? arrayContains : arraysEqual;
            return op(data[name], value);

        case 'RegExp':
            if (!isArray(data[name])) {
                return Boolean(data[name] && data[name].match(value));
            }

            if (!withinArray) {
                return false;
            }

            return arrayContains(data[name], value);

        case 'Number':
            value = String(value);
            // omit break;
        case 'String':
            if (!isArray(data[name])) {
                return data[name] === value;
            }

            if (!withinArray) {
                return false;
            }

            return arrayContains(data[name], value);

        default:
            throw new TypeError("URI.hasQuery() accepts undefined, boolean, string, number, RegExp, Function as the value parameter");
    }
};


URI.commonPath = function(one, two) {
    var length = Math.min(one.length, two.length);
    var pos;

    // find first non-matching character
    for (pos = 0; pos < length; pos++) {
        if (one.charAt(pos) !== two.charAt(pos)) {
            pos--;
            break;
        }
    }

    if (pos < 1) {
        return one.charAt(0) === two.charAt(0) && one.charAt(0) === '/' ? '/' : '';
    }
    
    // revert to last /
    if (one.charAt(pos) !== '/' || two.charAt(pos) !== '/') {
        pos = one.substring(0, pos).lastIndexOf('/');
    }

    return one.substring(0, pos + 1);
};

URI.withinString = function(string, callback) {
    // expression used is "gruber revised" (@gruber v2) determined to be the best solution in
    // a regex sprint we did a couple of ages ago at
    // * http://mathiasbynens.be/demo/url-regex
    // * http://rodneyrehm.de/t/url-regex.html

    return string.replace(URI.find_uri_expression, callback);
};

URI.ensureValidHostname = function(v) {
    // Theoretically URIs allow percent-encoding in Hostnames (according to RFC 3986)
    // they are not part of DNS and therefore ignored by URI.js

    if (v.match(URI.invalid_hostname_characters)) {
        // test punycode
        if (!punycode) {
            throw new TypeError("Hostname '" + v + "' contains characters other than [A-Z0-9.-] and Punycode.js is not available");
        }

        if (punycode.toASCII(v).match(URI.invalid_hostname_characters)) {
            throw new TypeError("Hostname '" + v + "' contains characters other than [A-Z0-9.-]");
        }
    }
};

// noConflict
URI.noConflict = function(removeAll) {
    if (removeAll) {
        var unconflicted = {
            URI: this.noConflict()
        };

        if (URITemplate && typeof URITemplate.noConflict == "function") {
            unconflicted.URITemplate = URITemplate.noConflict();
        }

        if (IPv6 && typeof IPv6.noConflict == "function") {
            unconflicted.IPv6 = IPv6.noConflict();
        }

        if (SecondLevelDomains && typeof SecondLevelDomains.noConflict == "function") {
            unconflicted.SecondLevelDomains = SecondLevelDomains.noConflict();
        }

        return unconflicted;
    } else if (root.URI === this) {
        root.URI = _URI;
    }

    return this;
};

p.build = function(deferBuild) {
    if (deferBuild === true) {
        this._deferred_build = true;
    } else if (deferBuild === undefined || this._deferred_build) {
        this._string = URI.build(this._parts);
        this._deferred_build = false;
    }

    return this;
};

p.clone = function() {
    return new URI(this);
};

p.valueOf = p.toString = function() {
    return this.build(false)._string;
};

// generate simple accessors
_parts = {protocol: 'protocol', username: 'username', password: 'password', hostname: 'hostname',  port: 'port'};
generateAccessor = function(_part){
    return function(v, build) {
        if (v === undefined) {
            return this._parts[_part] || "";
        } else {
            this._parts[_part] = v || null;
            this.build(!build);
            return this;
        }
    };
};

for (_part in _parts) {                                                                                                                                                                                        
    p[_part] = generateAccessor(_parts[_part]);
}

// generate accessors with optionally prefixed input
_parts = {query: '?', fragment: '#'};
generateAccessor = function(_part, _key){
    return function(v, build) {
        if (v === undefined) {
            return this._parts[_part] || "";
        } else {
            if (v !== null) {
                v = v + "";
                if (v.charAt(0) === _key) {
                    v = v.substring(1);
                }
            }

            this._parts[_part] = v;
            this.build(!build);
            return this;
        }
    };
};

for (_part in _parts) {
    p[_part] = generateAccessor(_part, _parts[_part]);
}

// generate accessors with prefixed output
_parts = {search: ['?', 'query'], hash: ['#', 'fragment']};
generateAccessor = function(_part, _key){
    return function(v, build) {
        var t = this[_part](v, build);
        return typeof t === "string" && t.length ? (_key + t) : t;
    };
};

for (_part in _parts) {
    p[_part] = generateAccessor(_parts[_part][1], _parts[_part][0]);
}

p.pathname = function(v, build) {
    if (v === undefined || v === true) {
        var res = this._parts.path || (this._parts.hostname ? '/' : '');
        return v ? URI.decodePath(res) : res;
    } else {
        this._parts.path = v ? URI.recodePath(v) : "/";
        this.build(!build);
        return this;
    }
};
p.path = p.pathname;
p.href = function(href, build) {
    var key;
    
    if (href === undefined) {
        return this.toString();
    }

    this._string = "";
    this._parts = URI._parts();

    var _URI = href instanceof URI;
    var _object = typeof href === "object" && (href.hostname || href.path || href.pathname);
    if (href.nodeName) {
        var attribute = URI.getDomAttribute(href);
        href = href[attribute] || "";
        _object = false;
    }
    
    // window.location is reported to be an object, but it's not the sort
    // of object we're looking for: 
    // * location.protocol ends with a colon
    // * location.query != object.search
    // * location.hash != object.fragment
    // simply serializing the unknown object should do the trick 
    // (for location, not for everything...)
    if (!_URI && _object && href.pathname !== undefined) {
        href = href.toString();
    }

    if (typeof href === "string") {
        this._parts = URI.parse(href, this._parts);
    } else if (_URI || _object) {
        var src = _URI ? href._parts : href;
        for (key in src) {
            if (hasOwn.call(this._parts, key)) {
                this._parts[key] = src[key];
            }
        }
    } else {
        throw new TypeError("invalid input");
    }

    this.build(!build);
    return this;
};

// identification accessors
p.is = function(what) {
    var ip = false;
    var ip4 = false;
    var ip6 = false;
    var name = false;
    var sld = false;
    var idn = false;
    var punycode = false;
    var relative = !this._parts.urn;

    if (this._parts.hostname) {
        relative = false;
        ip4 = URI.ip4_expression.test(this._parts.hostname);
        ip6 = URI.ip6_expression.test(this._parts.hostname);
        ip = ip4 || ip6;
        name = !ip;
        sld = name && SLD && SLD.has(this._parts.hostname);
        idn = name && URI.idn_expression.test(this._parts.hostname);
        punycode = name && URI.punycode_expression.test(this._parts.hostname);
    }

    switch (what.toLowerCase()) {
        case 'relative':
            return relative;

        case 'absolute':
            return !relative;

        // hostname identification
        case 'domain':
        case 'name':
            return name;

        case 'sld':
            return sld;

        case 'ip':
            return ip;

        case 'ip4':
        case 'ipv4':
        case 'inet4':
            return ip4;

        case 'ip6':
        case 'ipv6':
        case 'inet6':
            return ip6;

        case 'idn':
            return idn;

        case 'url':
            return !this._parts.urn;

        case 'urn':
            return !!this._parts.urn;

        case 'punycode':
            return punycode;
    }

    return null;
};

// component specific input validation
var _protocol = p.protocol;
var _port = p.port;
var _hostname = p.hostname;

p.protocol = function(v, build) {
    if (v !== undefined) {
        if (v) {
            // accept trailing ://
            v = v.replace(/:(\/\/)?$/, '');

            if (v.match(/[^a-zA-z0-9\.+-]/)) {
                throw new TypeError("Protocol '" + v + "' contains characters other than [A-Z0-9.+-]");
            }
        }
    }
    return _protocol.call(this, v, build);
};
p.scheme = p.protocol;
p.port = function(v, build) {
    if (this._parts.urn) {
        return v === undefined ? '' : this;
    }

    if (v !== undefined) {
        if (v === 0) {
            v = null;
        }

        if (v) {
            v += "";
            if (v.charAt(0) === ":") {
                v = v.substring(1);
            }

            if (v.match(/[^0-9]/)) {
                throw new TypeError("Port '" + v + "' contains characters other than [0-9]");
            }
        }
    }
    return _port.call(this, v, build);
};
p.hostname = function(v, build) {
    if (this._parts.urn) {
        return v === undefined ? '' : this;
    }

    if (v !== undefined) {
        var x = {};
        URI.parseHost(v, x);
        v = x.hostname;
    }
    return _hostname.call(this, v, build);
};

// compound accessors
p.host = function(v, build) {
    if (this._parts.urn) {
        return v === undefined ? '' : this;
    }

    if (v === undefined) {
        return this._parts.hostname ? URI.buildHost(this._parts) : "";
    } else {
        URI.parseHost(v, this._parts);
        this.build(!build);
        return this;
    }
};
p.authority = function(v, build) {
    if (this._parts.urn) {
        return v === undefined ? '' : this;
    }

    if (v === undefined) {
        return this._parts.hostname ? URI.buildAuthority(this._parts) : "";
    } else {
        URI.parseAuthority(v, this._parts);
        this.build(!build);
        return this;
    }
};
p.userinfo = function(v, build) {
    if (this._parts.urn) {
        return v === undefined ? '' : this;
    }

    if (v === undefined) {
        if (!this._parts.username) {
            return "";
        }

        var t = URI.buildUserinfo(this._parts);
        return t.substring(0, t.length -1);
    } else {
        if (v[v.length-1] !== '@') {
            v += '@';
        }

        URI.parseUserinfo(v, this._parts);
        this.build(!build);
        return this;
    }
};
p.resource = function(v, build) {
    var parts;
    
    if (v === undefined) {
        return this.path() + this.search() + this.hash();
    }
    
    parts = URI.parse(v);
    this._parts.path = parts.path;
    this._parts.query = parts.query;
    this._parts.fragment = parts.fragment;
    this.build(!build);
    return this;
};

// fraction accessors
p.subdomain = function(v, build) {
    if (this._parts.urn) {
        return v === undefined ? '' : this;
    }

    // convenience, return "www" from "www.example.org"
    if (v === undefined) {
        if (!this._parts.hostname || this.is('IP')) {
            return "";
        }

        // grab domain and add another segment
        var end = this._parts.hostname.length - this.domain().length - 1;
        return this._parts.hostname.substring(0, end) || "";
    } else {
        var e = this._parts.hostname.length - this.domain().length;
        var sub = this._parts.hostname.substring(0, e);
        var replace = new RegExp('^' + escapeRegEx(sub));

        if (v && v.charAt(v.length - 1) !== '.') {
            v += ".";
        }

        if (v) {
            URI.ensureValidHostname(v);
        }

        this._parts.hostname = this._parts.hostname.replace(replace, v);
        this.build(!build);
        return this;
    }
};
p.domain = function(v, build) {
    if (this._parts.urn) {
        return v === undefined ? '' : this;
    }

    if (typeof v === 'boolean') {
        build = v;
        v = undefined;
    }

    // convenience, return "example.org" from "www.example.org"
    if (v === undefined) {
        if (!this._parts.hostname || this.is('IP')) {
            return "";
        }

        // if hostname consists of 1 or 2 segments, it must be the domain
        var t = this._parts.hostname.match(/\./g);
        if (t && t.length < 2) {
            return this._parts.hostname;
        }

        // grab tld and add another segment
        var end = this._parts.hostname.length - this.tld(build).length - 1;
        end = this._parts.hostname.lastIndexOf('.', end -1) + 1;
        return this._parts.hostname.substring(end) || "";
    } else {
        if (!v) {
            throw new TypeError("cannot set domain empty");
        }

        URI.ensureValidHostname(v);

        if (!this._parts.hostname || this.is('IP')) {
            this._parts.hostname = v;
        } else {
            var replace = new RegExp(escapeRegEx(this.domain()) + "$");
            this._parts.hostname = this._parts.hostname.replace(replace, v);
        }

        this.build(!build);
        return this;
    }
};
p.tld = function(v, build) {
    if (this._parts.urn) {
        return v === undefined ? '' : this;
    }

    if (typeof v === 'boolean') {
        build = v;
        v = undefined;
    }

    // return "org" from "www.example.org"
    if (v === undefined) {
        if (!this._parts.hostname || this.is('IP')) {
            return "";
        }

        var pos = this._parts.hostname.lastIndexOf('.');
        var tld = this._parts.hostname.substring(pos + 1);

        if (build !== true && SLD && SLD.list[tld.toLowerCase()]) {
            return SLD.get(this._parts.hostname) || tld;
        }

        return tld;
    } else {
        var replace;
        
        if (!v) {
            throw new TypeError("cannot set TLD empty");
        } else if (v.match(/[^a-zA-Z0-9-]/)) {
            if (SLD && SLD.is(v)) {
                replace = new RegExp(escapeRegEx(this.tld()) + "$");
                this._parts.hostname = this._parts.hostname.replace(replace, v);
            } else {
                throw new TypeError("TLD '" + v + "' contains characters other than [A-Z0-9]");
            }
        } else if (!this._parts.hostname || this.is('IP')) {
            throw new ReferenceError("cannot set TLD on non-domain host");
        } else {
            replace = new RegExp(escapeRegEx(this.tld()) + "$");
            this._parts.hostname = this._parts.hostname.replace(replace, v);
        }

        this.build(!build);
        return this;
    }
};
p.directory = function(v, build) {
    if (this._parts.urn) {
        return v === undefined ? '' : this;
    }

    if (v === undefined || v === true) {
        if (!this._parts.path && !this._parts.hostname) {
            return '';
        }

        if (this._parts.path === '/') {
            return '/';
        }

        var end = this._parts.path.length - this.filename().length - 1;
        var res = this._parts.path.substring(0, end) || (this._parts.hostname ? "/" : "");

        return v ? URI.decodePath(res) : res;

    } else {
        var e = this._parts.path.length - this.filename().length;
        var directory = this._parts.path.substring(0, e);
        var replace = new RegExp('^' + escapeRegEx(directory));

        // fully qualifier directories begin with a slash
        if (!this.is('relative')) {
            if (!v) {
                v = '/';
            }

            if (v.charAt(0) !== '/') {
                v = "/" + v;
            }
        }

        // directories always end with a slash
        if (v && v.charAt(v.length - 1) !== '/') {
            v += '/';
        }

        v = URI.recodePath(v);
        this._parts.path = this._parts.path.replace(replace, v);
        this.build(!build);
        return this;
    }
};
p.filename = function(v, build) {
    if (this._parts.urn) {
        return v === undefined ? '' : this;
    }

    if (v === undefined || v === true) {
        if (!this._parts.path || this._parts.path === '/') {
            return "";
        }

        var pos = this._parts.path.lastIndexOf('/');
        var res = this._parts.path.substring(pos+1);

        return v ? URI.decodePathSegment(res) : res;
    } else {
        var mutatedDirectory = false;
        
        if (v.charAt(0) === '/') {
            v = v.substring(1);
        }

        if (v.match(/\.?\//)) {
            mutatedDirectory = true;
        }

        var replace = new RegExp(escapeRegEx(this.filename()) + "$");
        v = URI.recodePath(v);
        this._parts.path = this._parts.path.replace(replace, v);

        if (mutatedDirectory) {
            this.normalizePath(build);
        } else {
            this.build(!build);
        }

        return this;
    }
};
p.suffix = function(v, build) {
    if (this._parts.urn) {
        return v === undefined ? '' : this;
    }

    if (v === undefined || v === true) {
        if (!this._parts.path || this._parts.path === '/') {
            return "";
        }

        var filename = this.filename();
        var pos = filename.lastIndexOf('.');
        var s, res;

        if (pos === -1) {
            return "";
        }

        // suffix may only contain alnum characters (yup, I made this up.)
        s = filename.substring(pos+1);
        res = (/^[a-z0-9%]+$/i).test(s) ? s : "";
        return v ? URI.decodePathSegment(res) : res;
    } else {
        if (v.charAt(0) === '.') {
            v = v.substring(1);
        }

        var suffix = this.suffix();
        var replace;

        if (!suffix) {
            if (!v) {
                return this;
            }

            this._parts.path += '.' + URI.recodePath(v);
        } else if (!v) {
            replace = new RegExp(escapeRegEx("." + suffix) + "$");
        } else {
            replace = new RegExp(escapeRegEx(suffix) + "$");
        }

        if (replace) {
            v = URI.recodePath(v);
            this._parts.path = this._parts.path.replace(replace, v);
        }

        this.build(!build);
        return this;
    }
};
p.segment = function(segment, v, build) {
    var separator = this._parts.urn ? ':' : '/';
    var path = this.path();
    var absolute = path.substring(0, 1) === '/';
    var segments = path.split(separator);

    if (segment !== undefined && typeof segment !== 'number') {
        build = v;
        v = segment;
        segment = undefined;
    }

    if (segment !== undefined && typeof segment !== 'number') {
        throw new Error("Bad segment '" + segment + "', must be 0-based integer");
    }

    if (absolute) {
        segments.shift();
    }

    if (segment < 0) {
        // allow negative indexes to address from the end
        segment = Math.max(segments.length + segment, 0);
    }

    if (v === undefined) {
        return segment === undefined
            ? segments
            : segments[segment];
    } else if (segment === null || segments[segment] === undefined) {
        if (isArray(v)) {
            segments = [];
            // collapse empty elements within array
            for (var i=0, l=v.length; i < l; i++) {
                if (!v[i].length && (!segments.length || !segments[segments.length -1].length)) {
                    continue;
                }
                
                if (segments.length && !segments[segments.length -1].length) {
                    segments.pop();
                }
                
                segments.push(v[i]);
            }
        } else if (v || (typeof v === "string")) {
            if (segments[segments.length -1] === "") {
                // empty trailing elements have to be overwritten
                // to prevent results such as /foo//bar
                segments[segments.length -1] = v;
            } else {
                segments.push(v);
            }
        }
    } else {
        if (v || (typeof v === "string" && v.length)) {
            segments[segment] = v;
        } else {
            segments.splice(segment, 1);
        }
    }

    if (absolute) {
        segments.unshift("");
    }

    return this.path(segments.join(separator), build);
};
p.segmentCoded = function(segment, v, build) {
    var segments, i, l;

    if (typeof segment !== 'number') {
        build = v;
        v = segment;
        segment = undefined;
    }

    if (v === undefined) {
        segments = this.segment(segment, v, build);
        if (!isArray(segments)) {
            segments = segments !== undefined ? URI.decode(segments) : undefined;
        } else {
            for (i = 0, l = segments.length; i < l; i++) {
                segments[i] = URI.decode(segments[i]);
            }
        }

        return segments;
    }

    if (!isArray(v)) {
        v = typeof v === 'string' ? URI.encode(v) : v;
    } else {
        for (i = 0, l = v.length; i < l; i++) {
            v[i] = URI.decode(v[i]);
        }
    }

    return this.segment(segment, v, build);
};

// mutating query string
var q = p.query;
p.query = function(v, build) {
    if (v === true) {
        return URI.parseQuery(this._parts.query, this._parts.escapeQuerySpace);
    } else if (typeof v === "function") {
        var data = URI.parseQuery(this._parts.query, this._parts.escapeQuerySpace);
        var result = v.call(this, data);
        this._parts.query = URI.buildQuery(result || data, this._parts.duplicateQueryParameters, this._parts.escapeQuerySpace);
        this.build(!build);
        return this;
    } else if (v !== undefined && typeof v !== "string") {
        this._parts.query = URI.buildQuery(v, this._parts.duplicateQueryParameters, this._parts.escapeQuerySpace);
        this.build(!build);
        return this;
    } else {
        return q.call(this, v, build);
    }
};
p.setQuery = function(name, value, build) {
    var data = URI.parseQuery(this._parts.query, this._parts.escapeQuerySpace);
    
    if (typeof name === "object") {
        for (var key in name) {
            if (hasOwn.call(name, key)) {
                data[key] = name[key];
            }
        }
    } else if (typeof name === "string") {
        data[name] = value !== undefined ? value : null;
    } else {
        throw new TypeError("URI.addQuery() accepts an object, string as the name parameter");
    }
    
    this._parts.query = URI.buildQuery(data, this._parts.duplicateQueryParameters, this._parts.escapeQuerySpace);
    if (typeof name !== "string") {
        build = value;
    }

    this.build(!build);
    return this;
};
p.addQuery = function(name, value, build) {
    var data = URI.parseQuery(this._parts.query, this._parts.escapeQuerySpace);
    URI.addQuery(data, name, value === undefined ? null : value);
    this._parts.query = URI.buildQuery(data, this._parts.duplicateQueryParameters, this._parts.escapeQuerySpace);
    if (typeof name !== "string") {
        build = value;
    }

    this.build(!build);
    return this;
};
p.removeQuery = function(name, value, build) {
    var data = URI.parseQuery(this._parts.query, this._parts.escapeQuerySpace);
    URI.removeQuery(data, name, value);
    this._parts.query = URI.buildQuery(data, this._parts.duplicateQueryParameters, this._parts.escapeQuerySpace);
    if (typeof name !== "string") {
        build = value;
    }

    this.build(!build);
    return this;
};
p.hasQuery = function(name, value, withinArray) {
    var data = URI.parseQuery(this._parts.query, this._parts.escapeQuerySpace);
    return URI.hasQuery(data, name, value, withinArray);
};
p.setSearch = p.setQuery;
p.addSearch = p.addQuery;
p.removeSearch = p.removeQuery;
p.hasSearch = p.hasQuery;

// sanitizing URLs
p.normalize = function() {
    if (this._parts.urn) {
        return this
            .normalizeProtocol(false)
            .normalizeQuery(false)
            .normalizeFragment(false)
            .build();
    }

    return this
        .normalizeProtocol(false)
        .normalizeHostname(false)
        .normalizePort(false)
        .normalizePath(false)
        .normalizeQuery(false)
        .normalizeFragment(false)
        .build();
};
p.normalizeProtocol = function(build) {
    if (typeof this._parts.protocol === "string") {
        this._parts.protocol = this._parts.protocol.toLowerCase();
        this.build(!build);
    }

    return this;
};
p.normalizeHostname = function(build) {
    if (this._parts.hostname) {
        if (this.is('IDN') && punycode) {
            this._parts.hostname = punycode.toASCII(this._parts.hostname);
        } else if (this.is('IPv6') && IPv6) {
            this._parts.hostname = IPv6.best(this._parts.hostname);
        }

        this._parts.hostname = this._parts.hostname.toLowerCase();
        this.build(!build);
    }

    return this;
};
p.normalizePort = function(build) {
    // remove port of it's the protocol's default
    if (typeof this._parts.protocol === "string" && this._parts.port === URI.defaultPorts[this._parts.protocol]) {
        this._parts.port = null;
        this.build(!build);
    }

    return this;
};
p.normalizePath = function(build) {
    if (this._parts.urn) {
        return this;
    }

    if (!this._parts.path || this._parts.path === '/') {
        return this;
    }

    var _was_relative;
    var _path = this._parts.path;
    var _parent, _pos;

    // handle relative paths
    if (_path.charAt(0) !== '/') {
        _was_relative = true;
        _path = '/' + _path;
    }

    // resolve simples
    _path = _path
        .replace(/(\/(\.\/)+)|(\/\.$)/g, '/')
        .replace(/\/{2,}/g, '/');

    // resolve parents
    while (true) {
        _parent = _path.indexOf('/../');
        if (_parent === -1) {
            // no more ../ to resolve
            break;
        } else if (_parent === 0) {
            // top level cannot be relative...
            _path = _path.substring(3);
            break;
        }

        _pos = _path.substring(0, _parent).lastIndexOf('/');
        if (_pos === -1) {
            _pos = _parent;
        }
        _path = _path.substring(0, _pos) + _path.substring(_parent + 3);
    }

    // revert to relative
    if (_was_relative && this.is('relative')) {
        _path = _path.substring(1);
    }

    _path = URI.recodePath(_path);
    this._parts.path = _path;
    this.build(!build);
    return this;
};
p.normalizePathname = p.normalizePath;
p.normalizeQuery = function(build) {
    if (typeof this._parts.query === "string") {
        if (!this._parts.query.length) {
            this._parts.query = null;
        } else {
            this.query(URI.parseQuery(this._parts.query, this._parts.escapeQuerySpace));
        }

        this.build(!build);
    }

    return this;
};
p.normalizeFragment = function(build) {
    if (!this._parts.fragment) {
        this._parts.fragment = null;
        this.build(!build);
    }

    return this;
};
p.normalizeSearch = p.normalizeQuery;
p.normalizeHash = p.normalizeFragment;

p.iso8859 = function() {
    // expect unicode input, iso8859 output
    var e = URI.encode;
    var d = URI.decode;

    URI.encode = escape;
    URI.decode = decodeURIComponent;
    this.normalize();
    URI.encode = e;
    URI.decode = d;
    return this;
};

p.unicode = function() {
    // expect iso8859 input, unicode output
    var e = URI.encode;
    var d = URI.decode;

    URI.encode = strictEncodeURIComponent;
    URI.decode = unescape;
    this.normalize();
    URI.encode = e;
    URI.decode = d;
    return this;
};

p.readable = function() {
    var uri = this.clone();
    // removing username, password, because they shouldn't be displayed according to RFC 3986
    uri.username("").password("").normalize();
    var t = '';
    if (uri._parts.protocol) {
        t += uri._parts.protocol + '://';
    }

    if (uri._parts.hostname) {
        if (uri.is('punycode') && punycode) {
            t += punycode.toUnicode(uri._parts.hostname);
            if (uri._parts.port) {
                t += ":" + uri._parts.port;
            }
        } else {
            t += uri.host();
        }
    }

    if (uri._parts.hostname && uri._parts.path && uri._parts.path.charAt(0) !== '/') {
        t += '/';
    }

    t += uri.path(true);
    if (uri._parts.query) {
        var q = '';
        for (var i = 0, qp = uri._parts.query.split('&'), l = qp.length; i < l; i++) {
            var kv = (qp[i] || "").split('=');
            q += '&' + URI.decodeQuery(kv[0], this._parts.escapeQuerySpace)
                .replace(/&/g, '%26');

            if (kv[1] !== undefined) {
                q += "=" + URI.decodeQuery(kv[1], this._parts.escapeQuerySpace)
                    .replace(/&/g, '%26');
            }
        }
        t += '?' + q.substring(1);
    }

    t += URI.decodeQuery(uri.hash(), true);
    return t;
};

// resolving relative and absolute URLs
p.absoluteTo = function(base) {
    var resolved = this.clone();
    var properties = ['protocol', 'username', 'password', 'hostname', 'port'];
    var basedir, i, p;

    if (this._parts.urn) {
        throw new Error('URNs do not have any generally defined hierarchical components');
    }

    if (!(base instanceof URI)) {
        base = new URI(base);
    }
    
    if (!resolved._parts.protocol) {
        resolved._parts.protocol = base._parts.protocol;
    }
    
    if (this._parts.hostname) {
        return resolved;
    }

    for (i = 0; p = properties[i]; i++) {
        resolved._parts[p] = base._parts[p];
    }
    
    properties = ['query', 'path'];
    for (i = 0; p = properties[i]; i++) {
        if (!resolved._parts[p] && base._parts[p]) {
            resolved._parts[p] = base._parts[p];
        }
    }

    if (resolved.path().charAt(0) !== '/') {
        basedir = base.directory();
        resolved._parts.path = (basedir ? (basedir + '/') : '') + resolved._parts.path;
        resolved.normalizePath();
    }

    resolved.build();
    return resolved;
};
p.relativeTo = function(base) {
    var relative = this.clone().normalize();
    var relativeParts, baseParts, common, relativePath, basePath;

    if (relative._parts.urn) {
        throw new Error('URNs do not have any generally defined hierarchical components');
    }

    base = new URI(base).normalize();
    relativeParts = relative._parts;
    baseParts = base._parts;
    relativePath = relative.path();
    basePath = base.path();

    if (relativePath.charAt(0) !== '/') {
        throw new Error('URI is already relative');
    }

    if (basePath.charAt(0) !== '/') {
        throw new Error('Cannot calculate a URI relative to another relative URI');
    }

    if (relativeParts.protocol === baseParts.protocol) {
        relativeParts.protocol = null;
    }

    if (relativeParts.username !== baseParts.username || relativeParts.password !== baseParts.password) {
        return relative.build();
    }

    if (relativeParts.protocol !== null || relativeParts.username !== null || relativeParts.password !== null) {
        return relative.build();
    }

    if (relativeParts.hostname === baseParts.hostname && relativeParts.port === baseParts.port) {
        relativeParts.hostname = null;
        relativeParts.port = null;
    } else {
        return relative.build();
    }

    if (relativePath === basePath) {
        relativeParts.path = '';
        return relative.build();
    }
    
    // determine common sub path
    common = URI.commonPath(relative.path(), base.path());

    // If the paths have nothing in common, return a relative URL with the absolute path.
    if (!common) {
        return relative.build();
    }

    var parents = baseParts.path
        .substring(common.length)
        .replace(/[^\/]*$/, '')
        .replace(/.*?\//g, '../');

    relativeParts.path = parents + relativeParts.path.substring(common.length);

    return relative.build();
};

// comparing URIs
p.equals = function(uri) {
    var one = this.clone();
    var two = new URI(uri);
    var one_map = {};
    var two_map = {};
    var checked = {};
    var one_query, two_query, key;

    one.normalize();
    two.normalize();

    // exact match
    if (one.toString() === two.toString()) {
        return true;
    }

    // extract query string
    one_query = one.query();
    two_query = two.query();
    one.query("");
    two.query("");

    // definitely not equal if not even non-query parts match
    if (one.toString() !== two.toString()) {
        return false;
    }

    // query parameters have the same length, even if they're permuted
    if (one_query.length !== two_query.length) {
        return false;
    }

    one_map = URI.parseQuery(one_query, this._parts.escapeQuerySpace);
    two_map = URI.parseQuery(two_query, this._parts.escapeQuerySpace);

    for (key in one_map) {
        if (hasOwn.call(one_map, key)) {
            if (!isArray(one_map[key])) {
                if (one_map[key] !== two_map[key]) {
                    return false;
                }
            } else if (!arraysEqual(one_map[key], two_map[key])) {
                return false;
            }

            checked[key] = true;
        }
    }

    for (key in two_map) {
        if (hasOwn.call(two_map, key)) {
            if (!checked[key]) {
                // two contains a parameter not present in one
                return false;
            }
        }
    }

    return true;
};

// state
p.duplicateQueryParameters = function(v) {
    this._parts.duplicateQueryParameters = !!v;
    return this;
};

p.escapeQuerySpace = function(v) {
    this._parts.escapeQuerySpace = !!v;
    return this;
};

return URI;
}));