/**
 * Copyright 2017 Google Inc. All rights reserved.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

var http = require('http');
var await = require('./utilities').await;

class WebServer {
    constructor() {
        this._server = http.createServer();
        this.objectName = 'WebServer';
        this.listenOnPort = this.listen;
        this.newRequest = function(req, res) { }
        Object.defineProperty(this, 'port', {
            get: () => {
                if (!this._server.listening)
                    return '';
                return this._server.address().port + '';
            },
            enumerable: true,
            configurable: false
        });
    }

    close() {
        this._server.close();
    }

    /**
     * @param {nubmer} port
     * @return {boolean}
     */
    listen(port, callback) {
        if (this._server.listening)
            return false;
        this.newRequest = callback;
        this._server.listen(port);
        var errorPromise = new Promise(x => this._server.once('error', x));
        var successPromise = new Promise(x => this._server.once('listening', x));
        await(Promise.race([errorPromise, successPromise]));
        if (!this._server.listening)
            return false;

        this._server.on('request', (req, res) => {
            res.close = res.end.bind(res);
            var headers = res.getHeaders();
            res.headers = [];
            for (var key in headers) {
                res.headers.push({
                    name: key,
                    value: headers[key]
                });
            }
            res.header = res.getHeader;
            res.setHeaders = (headers) => {
                for (var key in headers)
                    res.setHeader(key, headers[key]);
            }
            Object.defineProperty(res, 'statusCode', {
                enumerable: true,
                configurable: true,
                writable: true,
                value: res.statusCode
            });
            this.newRequest.call(null, req, res);
        });
        return true;
    }
}

module.exports = WebServer;