var _ = require("lodash");

var _MessageUtils = {
    getContentType: function (message) {
        return this.get_first_header(message, /^Content-Type$/i);
    },
    get_first_header: function (message, regex) {
        //FIXME: Cache Invalidation.
        if (!message._headerLookups)
            Object.defineProperty(message, "_headerLookups", {
                value: {},
                configurable: false,
                enumerable: false,
                writable: false
            });
        if (!(regex in message._headerLookups)) {
            var header;
            for (var i = 0; i < message.headers.length; i++) {
                if (!!message.headers[i][0].match(regex)) {
                    header = message.headers[i];
                    break;
                }
            }
            message._headerLookups[regex] = header ? header[1] : undefined;
        }
        return message._headerLookups[regex];
    },
    match_header: function (message, regex) {
        var headers = message.headers;
        var i = headers.length;
        while (i--) {
            if (regex.test(headers[i].join(" "))) {
                return headers[i];
            }
        }
        return false;
    }
};

var defaultPorts = {
    "http": 80,
    "https": 443
};

var RequestUtils = _.extend(_MessageUtils, {
    pretty_host: function (request) {
        //FIXME: Add hostheader
        return request.host;
    },
    pretty_url: function (request) {
        var port = "";
        if (defaultPorts[request.scheme] !== request.port) {
            port = ":" + request.port;
        }
        return request.scheme + "://" + this.pretty_host(request) + port + request.path;
    }
});

var ResponseUtils = _.extend(_MessageUtils, {});


module.exports = {
    ResponseUtils: ResponseUtils,
    RequestUtils: RequestUtils

}