text: 'use strict';
  
  /* eslint func-names: off */
  
  const fs = require('fs');
  const http = require('http');
  const path = require('path');
  const url = require('url');
  const chokidar = require('chokidar');
  const compress = require('compression');
  const del = require('del');
  const express = require('express');
  const httpProxyMiddleware = require('http-proxy-middleware');
  const ip = require('ip');
  const killable = require('killable');
  const serveIndex = require('serve-index');
  const historyApiFallback = require('connect-history-api-fallback');
  const selfsigned = require('selfsigned');
  const sockjs = require('sockjs');
  const spdy = require('spdy');
  const webpack = require('webpack');
  const webpackDevMiddleware = require('webpack-dev-middleware');
  const createLog = require('./createLog');
  const OptionsValidationError = require('./OptionsValidationError');
  const optionsSchema = require('./optionsSchema.json');
  
  const clientStats = { all: false, assets: true, warnings: true, errors: true, errorDetails: false, hash: true };
  
  function Server(compiler, options, _log) {
    // Default options
    if (!options) options = {};
    this.log = _log || createLog(options);
  
    const validationErrors = webpack.validateSchema(optionsSchema, options);
    if (validationErrors.length) {
      throw new OptionsValidationError(validationErrors);
    }
  
    if (options.lazy && !options.filename) {
      throw new Error("'filename' option must be set in lazy mode.");
    }
  
    this.hot = options.hot || options.hotOnly;
    this.headers = options.headers;
    this.clientLogLevel = options.clientLogLevel;
    this.clientOverlay = options.overlay;
    this.progress = options.progress;
    this.disableHostCheck = !!options.disableHostCheck;
    this.publicHost = options.public;
    this.allowedHosts = options.allowedHosts;
    this.sockets = [];
    this.contentBaseWatchers = [];
    this.watchOptions = options.watchOptions || {};
  
    // Listening for events
    const invalidPlugin = () => {
      this.sockWrite(this.sockets, 'invalid');
    };
    if (this.progress) {
      const progressPlugin = new webpack.ProgressPlugin((percent, msg, addInfo) => {
        percent = Math.floor(percent * 100);
        if (percent === 100) msg = 'Compilation completed';
        if (addInfo) msg = `${msg} (${addInfo})`;
        this.sockWrite(this.sockets, 'progress-update', { percent, msg });
      });
      progressPlugin.apply(compiler);
    }
  
    const addCompilerHooks = (comp) => {
      comp.hooks.compile.tap('webpack-dev-server', invalidPlugin);
      comp.hooks.invalid.tap('webpack-dev-server', invalidPlugin);
      comp.hooks.done.tap('webpack-dev-server', (stats) => {
        this._sendStats(this.sockets, stats.toJson(clientStats));
        this._stats = stats;
      });
    };
    if (compiler.compilers) {
      compiler.compilers.forEach(addCompilerHooks);
    } else {
      addCompilerHooks(compiler);
    }
  
    // Init express server
    const app = this.app = new express(); // eslint-disable-line
  
    app.all('*', (req, res, next) => { // eslint-disable-line
      if (this.checkHost(req.headers)) { return next(); }
      res.send('Invalid Host header');
    });
  
    const wdmOptions = { logLevel: this.log.options.level };
  
    // middleware for serving webpack bundle
    this.middleware = webpackDevMiddleware(compiler, Object.assign({}, options, wdmOptions));
  
    app.get('/__webpack_dev_server__/live.bundle.js', (req, res) => {
      res.setHeader('Content-Type', 'application/javascript');
      fs.createReadStream(path.join(__dirname, '..', 'client', 'live.bundle.js')).pipe(res);
    });
  
    app.get('/__webpack_dev_server__/sockjs.bundle.js', (req, res) => {
      res.setHeader('Content-Type', 'application/javascript');
      fs.createReadStream(path.join(__dirname, '..', 'client', 'sockjs.bundle.js')).pipe(res);
    });
  
    app.get('/webpack-dev-server.js', (req, res) => {
      res.setHeader('Content-Type', 'application/javascript');
      fs.createReadStream(path.join(__dirname, '..', 'client', 'index.bundle.js')).pipe(res);
    });
  
    app.get('/webpack-dev-server/*', (req, res) => {
      res.setHeader('Content-Type', 'text/html');
      fs.createReadStream(path.join(__dirname, '..', 'client', 'live.html')).pipe(res);
    });
  
    app.get('/webpack-dev-server', (req, res) => {
      res.setHeader('Content-Type', 'text/html');
      res.write('<!DOCTYPE html><html><head><meta charset="utf-8"/></head><body>');
      const outputPath = this.middleware.getFilenameFromUrl(options.publicPath || '/');
      const filesystem = this.middleware.fileSystem;
  
      function writeDirectory(baseUrl, basePath) {
        const content = filesystem.readdirSync(basePath);
        res.write('<ul>');
        content.forEach((item) => {
          const p = `${basePath}/${item}`;
          if (filesystem.statSync(p).isFile()) {
            res.write('<li><a href="');
            res.write(baseUrl + item);
            res.write('">');
            res.write(item);
            res.write('</a></li>');
            if (/\.js$/.test(item)) {
              const htmlItem = item.substr(0, item.length - 3);
              res.write('<li><a href="');
              res.write(baseUrl + htmlItem);
              res.write('">');
              res.write(htmlItem);
              res.write('</a> (magic html for ');
              res.write(item);
              res.write(') (<a href="');
              res.write(baseUrl.replace(/(^(https?:\/\/[^\/]+)?\/)/, "$1webpack-dev-server/") + htmlItem); // eslint-disable-line
              res.write('">webpack-dev-server</a>)</li>');
            }
          } else {
            res.write('<li>');
            res.write(item);
            res.write('<br>');
            writeDirectory(`${baseUrl + item}/`, p);
            res.write('</li>');
          }
        });
        res.write('</ul>');
      }
      writeDirectory(options.publicPath || '/', outputPath);
      res.end('</body></html>');
    });
  
    let contentBase;
    if (options.contentBase !== undefined) { // eslint-disable-line
      contentBase = options.contentBase; // eslint-disable-line
    } else {
      contentBase = process.cwd();
    }
  
    // Keep track of websocket proxies for external websocket upgrade.
    const websocketProxies = [];
  
    const features = {
      compress() {
        if (options.compress) {
          // Enable gzip compression.
          app.use(compress());
        }
      },
  
      proxy() {
        if (options.proxy) {
          /**
            * Assume a proxy configuration specified as:
            * proxy: {
            *   'context': { options }
            * }
            * OR
            * proxy: {
            *   'context': 'target'
            * }
            */
          if (!Array.isArray(options.proxy)) {
            options.proxy = Object.keys(options.proxy).map((context) => {
              let proxyOptions;
              // For backwards compatibility reasons.
              const correctedContext = context.replace(/^\*$/, '**').replace(/\/\*$/, '');
  
              if (typeof options.proxy[context] === 'string') {
                proxyOptions = {
                  context: correctedContext,
                  target: options.proxy[context]
                };
              } else {
                proxyOptions = Object.assign({}, options.proxy[context]);
                proxyOptions.context = correctedContext;
              }
              proxyOptions.logLevel = proxyOptions.logLevel || 'warn';
  
              return proxyOptions;
            });
          }
  
          const getProxyMiddleware = (proxyConfig) => {
            const context = proxyConfig.context || proxyConfig.path;
  
            // It is possible to use the `bypass` method without a `target`.
            // However, the proxy middleware has no use in this case, and will fail to instantiate.
            if (proxyConfig.target) {
              return httpProxyMiddleware(context, proxyConfig);
            }
          };
  
          /**
          * Assume a proxy configuration specified as:
          * proxy: [
          *   {
          *     context: ...,
          *     ...options...
          *   },
          *   // or:
          *   function() {
          *     return {
          *       context: ...,
          *       ...options...
          *     };
          *   }
          * ]
          */
          options.proxy.forEach((proxyConfigOrCallback) => {
            let proxyConfig;
            let proxyMiddleware;
  
            if (typeof proxyConfigOrCallback === 'function') {
              proxyConfig = proxyConfigOrCallback();
            } else {
              proxyConfig = proxyConfigOrCallback;
            }
  
            proxyMiddleware = getProxyMiddleware(proxyConfig);
            if (proxyConfig.ws) {
              websocketProxies.push(proxyMiddleware);
            }
  
            app.use((req, res, next) => {
              if (typeof proxyConfigOrCallback === 'function') {
                const newProxyConfig = proxyConfigOrCallback();
                if (newProxyConfig !== proxyConfig) {
                  proxyConfig = newProxyConfig;
                  proxyMiddleware = getProxyMiddleware(proxyConfig);
                }
              }
              const bypass = typeof proxyConfig.bypass === 'function';
              // eslint-disable-next-line
              const bypassUrl = bypass && proxyConfig.bypass(req, res, proxyConfig) || false;
  
              if (bypassUrl) {
                req.url = bypassUrl;
                next();
              } else if (proxyMiddleware) {
                return proxyMiddleware(req, res, next);
              } else {
                next();
              }
            });
          });
        }
      },
  
      historyApiFallback() {
        if (options.historyApiFallback) {
          // Fall back to /index.html if nothing else matches.
          app.use(historyApiFallback(typeof options.historyApiFallback === 'object' ? options.historyApiFallback : null));
        }
      },
  
      contentBaseFiles: () => {
        if (Array.isArray(contentBase)) {
          contentBase.forEach((item) => {
            app.get('*', express.static(item));
          });
        } else if (/^(https?:)?\/\//.test(contentBase)) {
          this.log.warn('Using a URL as contentBase is deprecated and will be removed in the next major version. Please use the proxy option instead.');
          this.log.warn('proxy: {\n\t"*": "<your current contentBase configuration>"\n}'); // eslint-disable-line quotes
          // Redirect every request to contentBase
          app.get('*', (req, res) => {
            res.writeHead(302, {
              Location: contentBase + req.path + (req._parsedUrl.search || '')
            });
            res.end();
          });
        } else if (typeof contentBase === 'number') {
          this.log.warn('Using a number as contentBase is deprecated and will be removed in the next major version. Please use the proxy option instead.');
          this.log.warn('proxy: {\n\t"*": "//localhost:<your current contentBase configuration>"\n}'); // eslint-disable-line quotes
          // Redirect every request to the port contentBase
          app.get('*', (req, res) => {
            res.writeHead(302, {
              Location: `//localhost:${contentBase}${req.path}${req._parsedUrl.search || ''}`
            });
            res.end();
          });
        } else {
          // route content request
          app.get('*', express.static(contentBase, options.staticOptions));
        }
      },
  
      contentBaseIndex() {
        if (Array.isArray(contentBase)) {
          contentBase.forEach((item) => {
            app.get('*', serveIndex(item));
          });
        } else if (!/^(https?:)?\/\//.test(contentBase) && typeof contentBase !== 'number') {
          app.get('*', serveIndex(contentBase));
        }
      },
  
      watchContentBase: () => {
        if (/^(https?:)?\/\//.test(contentBase) || typeof contentBase === 'number') {
          throw new Error('Watching remote files is not supported.');
        } else if (Array.isArray(contentBase)) {
          contentBase.forEach((item) => {
            this._watch(item);
          });
        } else {
          this._watch(contentBase);
        }
      },
  
      before: () => {
        if (typeof options.before === 'function') {
          options.before(app, this);
        }
      },
  
      middleware: () => {
        // include our middleware to ensure it is able to handle '/index.html' request after redirect
        app.use(this.middleware);
      },
  
      after: () => {
        if (typeof options.after === 'function') { options.after(app, this); }
      },
  
      headers: () => {
        app.all('*', this.setContentHeaders.bind(this));
      },
  
      magicHtml: () => {
        app.get('*', this.serveMagicHtml.bind(this));
      },
  
      setup: () => {
        if (typeof options.setup === 'function') {
          this.log.warn('The `setup` option is deprecated and will be removed in v3. Please update your config to use `before`');
          options.setup(app, this);
        }
      }
    };
  
    const defaultFeatures = ['before', 'setup', 'headers', 'middleware'];
    if (options.proxy) { defaultFeatures.push('proxy', 'middleware'); }
    if (contentBase !== false) { defaultFeatures.push('contentBaseFiles'); }
    if (options.watchContentBase) { defaultFeatures.push('watchContentBase'); }
    if (options.historyApiFallback) {
      defaultFeatures.push('historyApiFallback', 'middleware');
      if (contentBase !== false) { defaultFeatures.push('contentBaseFiles'); }
    }
    defaultFeatures.push('magicHtml');
    if (contentBase !== false) { defaultFeatures.push('contentBaseIndex'); }
    // compress is placed last and uses unshift so that it will be the first middleware used
    if (options.compress) { defaultFeatures.unshift('compress'); }
    if (options.after) { defaultFeatures.push('after'); }
  
    (options.features || defaultFeatures).forEach((feature) => {
      features[feature]();
    });
  
    if (options.https) {
      // for keep supporting CLI parameters
      if (typeof options.https === 'boolean') {
        options.https = {
          key: options.key,
          cert: options.cert,
          ca: options.ca,
          pfx: options.pfx,
          passphrase: options.pfxPassphrase,
          requestCert: options.requestCert || false
        };
      }
  
      let fakeCert;
      if (!options.https.key || !options.https.cert) {
        // Use a self-signed certificate if no certificate was configured.
        // Cycle certs every 24 hours
        const certPath = path.join(__dirname, '../ssl/server.pem');
        let certExists = fs.existsSync(certPath);
  
        if (certExists) {
          const certStat = fs.statSync(certPath);
          const certTtl = 1000 * 60 * 60 * 24;
          const now = new Date();
  
          // cert is more than 30 days old, kill it with fire
          if ((now - certStat.ctime) / certTtl > 30) {
            this.log.info('SSL Certificate is more than 30 days old. Removing.');
            del.sync([certPath], { force: true });
            certExists = false;
          }
        }
  
        if (!certExists) {
          this.log.info('Generating SSL Certificate');
          const attrs = [{ name: 'commonName', value: 'localhost' }];
          const pems = selfsigned.generate(attrs, {
            algorithm: 'sha256',
            days: 30,
            keySize: 2048,
            extensions: [{
              name: 'basicConstraints',
              cA: true
            }, {
              name: 'keyUsage',
              keyCertSign: true,
              digitalSignature: true,
              nonRepudiation: true,
              keyEncipherment: true,
              dataEncipherment: true
            }, {
              name: 'subjectAltName',
              altNames: [
                {
                  // type 2 is DNS
                  type: 2,
                  value: 'localhost'
                },
                {
                  type: 2,
                  value: 'localhost.localdomain'
                },
                {
                  type: 2,
                  value: 'lvh.me'
                },
                {
                  type: 2,
                  value: '*.lvh.me'
                },
                {
                  type: 2,
                  value: '[::1]'
                },
                {
                  // type 7 is IP
                  type: 7,
                  ip: '127.0.0.1'
                },
                {
                  type: 7,
                  ip: 'fe80::1'
                }
              ]
            }]
          });
  
          fs.writeFileSync(certPath, pems.private + pems.cert, { encoding: 'utf-8' });
        }
        fakeCert = fs.readFileSync(certPath);
      }
  
      options.https.key = options.https.key || fakeCert;
      options.https.cert = options.https.cert || fakeCert;
  
      if (!options.https.spdy) {
        options.https.spdy = {
          protocols: ['h2', 'http/1.1']
        };
      }
  
      this.listeningApp = spdy.createServer(options.https, app);
    } else {
      this.listeningApp = http.createServer(app);
    }
  
    killable(this.listeningApp);
  
    // Proxy websockets without the initial http request
    // https://github.com/chimurai/http-proxy-middleware#external-websocket-upgrade
    websocketProxies.forEach(function (wsProxy) {
      this.listeningApp.on('upgrade', wsProxy.upgrade);
    }, this);
  }
  
  Server.prototype.use = function () {
    // eslint-disable-next-line
    this.app.use.apply(this.app, arguments);
  };
  
  Server.prototype.setContentHeaders = function (req, res, next) {
    if (this.headers) {
      for (const name in this.headers) { // eslint-disable-line
        res.setHeader(name, this.headers[name]);
      }
    }
  
    next();
  };
  
  Server.prototype.checkHost = function (headers) {
    // allow user to opt-out this security check, at own risk
    if (this.disableHostCheck) return true;
  
    // get the Host header and extract hostname
    // we don't care about port not matching
    const hostHeader = headers.host;
    if (!hostHeader) return false;
  
    // use the node url-parser to retrieve the hostname from the host-header.
    const hostname = url.parse(`//${hostHeader}`, false, true).hostname;
  
    // always allow requests with explicit IPv4 or IPv6-address.
    // A note on IPv6 addresses: hostHeader will always contain the brackets denoting
    // an IPv6-address in URLs, these are removed from the hostname in url.parse(),
    // so we have the pure IPv6-address in hostname.
    if (ip.isV4Format(hostname) || ip.isV6Format(hostname)) return true;
  
    // always allow localhost host, for convience
    if (hostname === 'localhost') return true;
  
    // allow if hostname is in allowedHosts
    if (this.allowedHosts && this.allowedHosts.length) {
      for (let hostIdx = 0; hostIdx < this.allowedHosts.length; hostIdx++) {
        const allowedHost = this.allowedHosts[hostIdx];
        if (allowedHost === hostname) return true;
  
        // support "." as a subdomain wildcard
        // e.g. ".example.com" will allow "example.com", "www.example.com", "subdomain.example.com", etc
        if (allowedHost[0] === '.') {
          // "example.com"
          if (hostname === allowedHost.substring(1)) return true;
          // "*.example.com"
          if (hostname.endsWith(allowedHost)) return true;
        }
      }
    }
  
    // allow hostname of listening adress
    if (hostname === this.listenHostname) return true;
  
    // also allow public hostname if provided
    if (typeof this.publicHost === 'string') {
      const idxPublic = this.publicHost.indexOf(':');
      const publicHostname = idxPublic >= 0 ? this.publicHost.substr(0, idxPublic) : this.publicHost;
      if (hostname === publicHostname) return true;
    }
  
    // disallow
    return false;
  };
  
  // delegate listen call and init sockjs
  Server.prototype.listen = function (port, hostname, fn) {
    this.listenHostname = hostname;
    const returnValue = this.listeningApp.listen(port, hostname, (err) => {
      const sockServer = sockjs.createServer({
        // Use provided up-to-date sockjs-client
        sockjs_url: '/__webpack_dev_server__/sockjs.bundle.js',
        // Limit useless logs
        log: (severity, line) => {
          if (severity === 'error') {
            this.log.error(line);
          } else {
            this.log.debug(line);
          }
        }
      });
  
      sockServer.on('connection', (conn) => {
        if (!conn) return;
        if (!this.checkHost(conn.headers)) {
          this.sockWrite([conn], 'error', 'Invalid Host header');
          conn.close();
          return;
        }
        this.sockets.push(conn);
  
        conn.on('close', () => {
          const connIndex = this.sockets.indexOf(conn);
          if (connIndex >= 0) {
            this.sockets.splice(connIndex, 1);
          }
        });
  
        if (this.clientLogLevel) { this.sockWrite([conn], 'log-level', this.clientLogLevel); }
  
        if (this.progress) { this.sockWrite([conn], 'progress', this.progress); }
  
        if (this.clientOverlay) { this.sockWrite([conn], 'overlay', this.clientOverlay); }
  
        if (this.hot) this.sockWrite([conn], 'hot');
  
        if (!this._stats) return;
        this._sendStats([conn], this._stats.toJson(clientStats), true);
      });
  
      sockServer.installHandlers(this.listeningApp, {
        prefix: '/sockjs-node'
      });
  
      if (fn) {
        fn.call(this.listeningApp, err);
      }
    });
  
    return returnValue;
  };
  
  Server.prototype.close = function (callback) {
    this.sockets.forEach((sock) => {
      sock.close();
    });
    this.sockets = [];
  
    this.contentBaseWatchers.forEach((watcher) => {
      watcher.close();
    });
    this.contentBaseWatchers = [];
  
    this.listeningApp.kill(() => {
      this.middleware.close(callback);
    });
  };
  
  Server.prototype.sockWrite = function (sockets, type, data) {
    sockets.forEach((sock) => {
      sock.write(JSON.stringify({
        type,
        data
      }));
    });
  };
  
  Server.prototype.serveMagicHtml = function (req, res, next) {
    const _path = req.path;
    try {
      if (!this.middleware.fileSystem.statSync(this.middleware.getFilenameFromUrl(`${_path}.js`)).isFile()) { return next(); }
      // Serve a page that executes the javascript
      res.write('<!DOCTYPE html><html><head><meta charset="utf-8"/></head><body><script type="text/javascript" charset="utf-8" src="');
      res.write(_path);
      res.write('.js');
      res.write(req._parsedUrl.search || '');
      res.end('"></script></body></html>');
    } catch (e) {
      return next();
    }
  };
  
  // send stats to a socket or multiple sockets
  Server.prototype._sendStats = function (sockets, stats, force) {
    if (!force &&
    stats &&
    (!stats.errors || stats.errors.length === 0) &&
    stats.assets &&
    stats.assets.every(asset => !asset.emitted)
    ) { return this.sockWrite(sockets, 'still-ok'); }
    this.sockWrite(sockets, 'hash', stats.hash);
    if (stats.errors.length > 0) { this.sockWrite(sockets, 'errors', stats.errors); } else if (stats.warnings.length > 0) { this.sockWrite(sockets, 'warnings', stats.warnings); } else { this.sockWrite(sockets, 'ok'); }
  };
  
  Server.prototype._watch = function (watchPath) {
    // duplicate the same massaging of options that watchpack performs
    // https://github.com/webpack/watchpack/blob/master/lib/DirectoryWatcher.js#L49
    // this isn't an elegant solution, but we'll improve it in the future
    const usePolling = this.watchOptions.poll ? true : undefined; // eslint-disable-line no-undefined
    const interval = typeof this.watchOptions.poll === 'number' ? this.watchOptions.poll : undefined; // eslint-disable-line no-undefined
    const options = {
      ignoreInitial: true,
      persistent: true,
      followSymlinks: false,
      depth: 0,
      atomic: false,
      alwaysStat: true,
      ignorePermissionErrors: true,
      ignored: this.watchOptions.ignored,
      usePolling,
      interval
    };
    const watcher = chokidar.watch(watchPath, options).on('change', () => {
      this.sockWrite(this.sockets, 'content-changed');
    });
  
    this.contentBaseWatchers.push(watcher);
  };
  
  Server.prototype.invalidate = function () {
    if (this.middleware) this.middleware.invalidate();
  };
  
  // Export this logic, so that other implementations, like task-runners can use it
  Server.addDevServerEntrypoints = require('./util/addDevServerEntrypoints');
  
  module.exports = Server;
  