text: var _ = require('underscore');
  var colors = require('colors');
  var fs = require('fs');
  var inquirer = require('inquirer');
  var M = require('mstring');
  var os = require('os');
  
  colors.setTheme({
    silly: 'rainbow',
    input: 'grey',
    verbose: 'cyan',
    prompt: 'grey',
    info: 'green',
    data: 'grey',
    help: 'white',
    warn: 'yellow',
    debug: 'blue',
    error: 'red'
  });
  
  inquirer.prompt({
    type: 'list',
    name: 'category',
    message: 'Hackathon Starter:',
    choices: ['☂ Authentication', '☎ Email Service', '☱ Exit']
  }, function(answer) {
  
    if (answer.category.match('Email Service')) {
      inquirer.prompt({
        type: 'list',
        name: 'email',
        message: 'Choose Email Delivery Service:',
        choices: ['SendGrid', 'Mailgun', 'Cancel']
      }, function(answer) {
  
        var index;
  
        var contactControllerFile = 'controllers/contact.js';
        var userControllerFile = 'controllers/user.js';
  
        var contactController = fs.readFileSync(contactControllerFile).toString().split(os.EOL);
        var userController = fs.readFileSync(userControllerFile).toString().split(os.EOL);
  
        if (answer.email.match('SendGrid')) {
  
          // Change SMPT Transport to SendGrid in controllers/contact.js
          index = contactController.indexOf('var smtpTransport = nodemailer.createTransport(\'SMTP\', {');
          contactController.splice(index + 1, 1, '  service: \'SendGrid\',');
          contactController.splice(index + 3, 1, '       user: secrets.sendgrid.user,');
          contactController.splice(index + 4, 1, '       pass: secrets.sendgrid.password');
          fs.writeFileSync(contactControllerFile, contactController.join(os.EOL));
  
          // Change SMPT Transport to SendGrid in controllers/user.js
          index = userController.indexOf('      var smtpTransport = nodemailer.createTransport(\'SMTP\', {');
          userController.splice(index + 1, 1, '        service: \'SendGrid\',');
          userController.splice(index + 3, 1, '          user: secrets.sendgrid.user,');
          userController.splice(index + 4, 1, '          pass: secrets.sendgrid.password');
          index = userController.indexOf('      var smtpTransport = nodemailer.createTransport(\'SMTP\', {', 1);
          userController.splice(index + 1, 1, '        service: \'SendGrid\',');
          userController.splice(index + 3, 1, '          user: secrets.sendgrid.user,');
          userController.splice(index + 4, 1, '          pass: secrets.sendgrid.password');
          fs.writeFileSync(userControllerFile, userController.join(os.EOL));
  
          console.log('✓ Email Delivery Service has been switched to'.info, 'SendGrid'.help);
        }
  
        if (answer.email.match('Mailgun')) {
  
          // Change SMPT Transport to Mailgun in controllers/contact.js
          index = contactController.indexOf('var smtpTransport = nodemailer.createTransport(\'SMTP\', {');
          contactController.splice(index + 1, 1, '  service: \'Mailgun\',');
          contactController.splice(index + 3, 1, '       user: secrets.mailgun.login,');
          contactController.splice(index + 4, 1, '       pass: secrets.mailgun.password');
          fs.writeFileSync(contactControllerFile, contactController.join(os.EOL));
  
          // Change SMPT Transport to Mailgun in controllers/user.js
          index = userController.indexOf('      var smtpTransport = nodemailer.createTransport(\'SMTP\', {');
          userController.splice(index + 1, 1, '        service: \'Mailgun\',');
          userController.splice(index + 3, 1, '          user: secrets.mailgun.login,');
          userController.splice(index + 4, 1, '          pass: secrets.mailgun.password');
          index = userController.indexOf('      var smtpTransport = nodemailer.createTransport(\'SMTP\', {', 1);
          userController.splice(index + 1, 1, '        service: \'Mailgun\',');
          userController.splice(index + 3, 1, '          user: secrets.mailgun.login,');
          userController.splice(index + 4, 1, '          pass: secrets.mailgun.password');
          fs.writeFileSync(userControllerFile, userController.join(os.EOL));
  
          console.log('✓ Email Delivery Service has been switched to'.info, '@'.error + 'mail'.data + 'gun'.error);
        }
      });
    }
  
    if (answer.category.match('Authentication')) {
      inquirer.prompt({
        type: 'checkbox',
        message: 'Select Authentication Providers',
        name: 'auth',
        choices: [
          new inquirer.Separator(M(function() {
            /***
  
             ╔══════════════════════════════════════════════════════════════════════╗
             ║ THIS TOOL IS STILL IN EXPERIMENTAL STAGE! USE AT YOUR OWN RISK.      ║
             ║ ALWAYS USE VERSION CONTROL SYSTEM SO YOU COULD REVERT THE CHANGES.   ║
             ║ REPORT BUGS AT HTTPS://GITHUB.COM/SAHAT/HACKATHON-STARTER/ISSUES/NEW ║
             ╚══════════════════════════════════════════════════════════════════════╝
  
            ***/
          })),
          { name: 'Facebook', checked: true },
          { name: 'GitHub', checked: true },
          { name: 'Google', checked: true },
          { name: 'Twitter', checked: true },
          { name: 'LinkedIn', checked: true },
          { name: 'Instagram' },
          new inquirer.Separator('Press ctrl+c to cancel'.warn)
        ]
      }, function(answer) {
        var index;
  
        var passportConfigFile = 'config/passport.js';
        var userModelFile = 'models/User.js';
        var appFile = 'app.js';
        var secretsFile = 'config/secrets.js';
        var profileTemplateFile = 'views/account/profile.jade';
        var loginTemplateFile = 'views/account/login.jade';
  
        var passportConfig = fs.readFileSync(passportConfigFile).toString().split(os.EOL);
        var loginTemplate = fs.readFileSync(loginTemplateFile).toString().split(os.EOL);
        var profileTemplate = fs.readFileSync(profileTemplateFile).toString().split(os.EOL);
        var userModel = fs.readFileSync(userModelFile).toString().split(os.EOL);
        var app = fs.readFileSync(appFile).toString().split(os.EOL);
        var secrets = fs.readFileSync(secretsFile).toString().split(os.EOL);
  
        /////////////////////////////
        // Facebook Authentication //
        /////////////////////////////
  
        var facebookRoutes = M(function() {
          /***
          app.get('/auth/facebook', passport.authenticate('facebook', { scope: ['email', 'user_location'] }));
          app.get('/auth/facebook/callback', passport.authenticate('facebook', { failureRedirect: '/login' }), function(req, res) {
            res.redirect(req.session.returnTo || '/');
          });
          ***/
        });
        var facebookStrategyRequire = "var FacebookStrategy = require('passport-facebook').Strategy;";
        var facebookStrategy = M(function() {
          /***
          // Sign in with Facebook.
  
          passport.use(new FacebookStrategy(secrets.facebook, function(req, accessToken, refreshToken, profile, done) {
            if (req.user) {
              User.findOne({ $or: [{ facebook: profile.id }, { email: profile.email }] }, function(err, existingUser) {
                if (existingUser) {
                  req.flash('errors', { msg: 'There is already a Facebook account that belongs to you. Sign in with that account or delete it, then link it with your current account.' });
                  done(err);
                } else {
                  User.findById(req.user.id, function(err, user) {
                    user.facebook = profile.id;
                    user.tokens.push({ kind: 'facebook', accessToken: accessToken });
                    user.profile.name = user.profile.name || profile.displayName;
                    user.profile.gender = user.profile.gender || profile._json.gender;
                    user.profile.picture = user.profile.picture || 'https://graph.facebook.com/' + profile.id + '/picture?type=large';
                    user.save(function(err) {
                      req.flash('info', { msg: 'Facebook account has been linked.' });
                      done(err, user);
                    });
                  });
                }
              });
            } else {
              User.findOne({ facebook: profile.id }, function(err, existingUser) {
                if (existingUser) return done(null, existingUser);
                User.findOne({ email: profile._json.email }, function(err, existingEmailUser) {
                  if (existingEmailUser) {
                    req.flash('errors', { msg: 'There is already an account using this email address. Sign in to that account and link it with Facebook manually from Account Settings.' });
                    done(err);
                  } else {
                    var user = new User();
                    user.email = profile._json.email;
                    user.facebook = profile.id;
                    user.tokens.push({ kind: 'facebook', accessToken: accessToken });
                    user.profile.name = profile.displayName;
                    user.profile.gender = profile._json.gender;
                    user.profile.picture = 'https://graph.facebook.com/' + profile.id + '/picture?type=large';
                    user.profile.location = (profile._json.location) ? profile._json.location.name : '';
                    user.save(function(err) {
                      done(err, user);
                    });
                  }
                });
              });
            }
          }));
  
          ***/
        });
        var facebookButton = M(function() {
          /***
                a.btn.btn-block.btn-facebook.btn-social(href='/auth/facebook')
                  i.fa.fa-facebook
                  | Sign in with Facebook
          ***/
        });
        var facebookLinkUnlink = M(function() {
          /***
  
            if user.facebook
              p: a.text-danger(href='/account/unlink/facebook') Unlink your Facebook account
            else
              p: a(href='/auth/facebook') Link your Facebook account
          ***/
        });
        var facebookModel = '  facebook: String,';
  
        if (_.contains(answer.auth, 'Facebook')) {
          if (passportConfig.indexOf(facebookStrategyRequire) < 0) {
  
            // Add Facebook to config/passport.js
            index = passportConfig.indexOf("var passport = require('passport');");
            passportConfig.splice(index + 1, 0, facebookStrategyRequire);
            index = passportConfig.indexOf('passport.deserializeUser(function(id, done) {');
            passportConfig.splice(index + 6, 0, facebookStrategy);
            fs.writeFileSync(passportConfigFile, passportConfig.join(os.EOL));
  
            // Add Facebook to views/account/login.jade
            loginTemplate.push(facebookButton);
            fs.writeFileSync(loginTemplateFile, loginTemplate.join(os.EOL));
  
            // Add Facebook to views/account/profile.jade
            index = profileTemplate.indexOf('    h3 Linked Accounts');
            profileTemplate.splice(index + 1, 0, facebookLinkUnlink);
            fs.writeFileSync(profileTemplateFile, profileTemplate.join(os.EOL));
  
            // Add Facebook to models/User.js
            index = userModel.indexOf('  tokens: Array,');
            userModel.splice(index - 1, 0, facebookModel);
            fs.writeFileSync(userModelFile, userModel.join(os.EOL));
  
            // Add Facebook to app.js
            index = app.indexOf(' * OAuth routes for sign-in.');
            app.splice(index + 3, 0, facebookRoutes);
            fs.writeFileSync(appFile, app.join(os.EOL));
  
            console.log('✓ Facebook authentication has been added.'.info);
          } else {
            console.log('✓ Facebook authentication is already active.'.data);
          }
        } else {
  
          // config/passport.js
          index = passportConfig.indexOf(facebookStrategyRequire);
          passportConfig.splice(index, 1);
          index = passportConfig.indexOf('// Sign in with Facebook.');
          passportConfig.splice(index, 47);
          fs.writeFileSync(passportConfigFile, passportConfig.join(os.EOL));
  
          // views/account/login.jade
          index = loginTemplate.indexOf("      a.btn.btn-block.btn-facebook.btn-social(href='/auth/facebook')");
          loginTemplate.splice(index, 3);
          fs.writeFileSync(loginTemplateFile, loginTemplate.join(os.EOL));
  
          // views/account/profile.jade
          index = profileTemplate.indexOf("  if user.facebook");
          profileTemplate.splice(index - 1, 5);
          fs.writeFileSync(profileTemplateFile, profileTemplate.join(os.EOL));
  
          // models/User.js
          index = userModel.indexOf('  facebook: String,');
          userModel.splice(index, 1);
          fs.writeFileSync(userModelFile, userModel.join(os.EOL));
  
          // Remove Facebook from app.js
          index = app.indexOf("app.get('/auth/facebook', passport.authenticate('facebook', { scope: ['email', 'user_location'] }));");
          app.splice(index, 4);
          fs.writeFileSync(appFile, app.join(os.EOL));
  
          console.log('✗ Facebook authentication has been removed.'.error);
        }
  
        ///////////////////////////
        // GitHub Authentication //
        ///////////////////////////
  
        var githubRoutes = M(function() {
          /***
          app.get('/auth/github', passport.authenticate('github'));
          app.get('/auth/github/callback', passport.authenticate('github', { failureRedirect: '/login' }), function(req, res) {
            res.redirect(req.session.returnTo || '/');
          });
          ***/
        });
        var githubStrategyRequire = "var GitHubStrategy = require('passport-github').Strategy;";
        var githubStrategy = M(function() {
          /***
          // Sign in with GitHub.
  
          passport.use(new GitHubStrategy(secrets.github, function(req, accessToken, refreshToken, profile, done) {
            if (req.user) {
              User.findOne({ $or: [{ github: profile.id }, { email: profile.email }] }, function(err, existingUser) {
                if (existingUser) {
                  req.flash('errors', { msg: 'There is already a GitHub account that belongs to you. Sign in with that account or delete it, then link it with your current account.' });
                  done(err);
                } else {
                  User.findById(req.user.id, function(err, user) {
                    user.github = profile.id;
                    user.tokens.push({ kind: 'github', accessToken: accessToken });
                    user.profile.name = user.profile.name || profile.displayName;
                    user.profile.picture = user.profile.picture || profile._json.avatar_url;
                    user.profile.location = user.profile.location || profile._json.location;
                    user.profile.website = user.profile.website || profile._json.blog;
                    user.save(function(err) {
                      req.flash('info', { msg: 'GitHub account has been linked.' });
                      done(err, user);
                    });
                  });
                }
              });
            } else {
              User.findOne({ github: profile.id }, function(err, existingUser) {
                if (existingUser) return done(null, existingUser);
                User.findOne({ email: profile._json.email }, function(err, existingEmailUser) {
                  if (existingEmailUser) {
                    req.flash('errors', { msg: 'There is already an account using this email address. Sign in to that account and link it with GitHub manually from Account Settings.' });
                    done(err);
                  } else {
                    var user = new User();
                    user.email = profile._json.email;
                    user.github = profile.id;
                    user.tokens.push({ kind: 'github', accessToken: accessToken });
                    user.profile.name = profile.displayName;
                    user.profile.picture = profile._json.avatar_url;
                    user.profile.location = profile._json.location;
                    user.profile.website = profile._json.blog;
                    user.save(function(err) {
                      done(err, user);
                    });
                  }
                });
              });
            }
          }));
  
          ***/
        });
  
        var githubButton = M(function() {
          /***
                a.btn.btn-block.btn-github.btn-social(href='/auth/github')
                  i.fa.fa-github
                  | Sign in with GitHub
          ***/
        });
        var githubLinkUnlink = M(function() {
          /***
  
            if user.github
              p: a.text-danger(href='/account/unlink/github') Unlink your GitHub account
            else
              p: a(href='/auth/github') Link your GitHub account
          ***/
        });
        var githubModel = '  github: String,';
  
        if (_.contains(answer.auth, 'GitHub')) {
          if (passportConfig.indexOf(githubStrategyRequire) < 0) {
  
            // config/passport.js
            index = passportConfig.indexOf("var passport = require('passport');");
            passportConfig.splice(index + 1, 0, githubStrategyRequire);
            index = passportConfig.indexOf('passport.deserializeUser(function(id, done) {');
            passportConfig.splice(index + 6, 0, githubStrategy);
            fs.writeFileSync(passportConfigFile, passportConfig.join(os.EOL));
  
            // views/account/login.jade
            loginTemplate.push(githubButton);
            fs.writeFileSync(loginTemplateFile, loginTemplate.join(os.EOL));
  
            // views/account/profile.jade
            index = profileTemplate.indexOf('    h3 Linked Accounts');
            profileTemplate.splice(index + 1, 0, githubLinkUnlink);
            fs.writeFileSync(profileTemplateFile, profileTemplate.join(os.EOL));
  
            // models/User.js
            index = userModel.indexOf('  tokens: Array,');
            userModel.splice(index - 1, 0, githubModel);
            fs.writeFileSync(userModelFile, userModel.join(os.EOL));
  
            // Add GitHub to app.js
            index = app.indexOf(' * OAuth routes for sign-in.');
            app.splice(index + 3, 0, githubRoutes);
            fs.writeFileSync(appFile, app.join(os.EOL));
  
            console.log('✓ GitHub authentication has been added.'.info);
          } else {
            console.log('✓ GitHub authentication is already active.'.data);
          }
        } else {
  
          // config/passport.js
          index = passportConfig.indexOf(githubStrategyRequire);
          passportConfig.splice(index, 1);
          index = passportConfig.indexOf('// Sign in with GitHub.');
          passportConfig.splice(index, 48);
          fs.writeFileSync(passportConfigFile, passportConfig.join(os.EOL));
  
          // views/account/login.jade
          index = loginTemplate.indexOf("      a.btn.btn-block.btn-github.btn-social(href='/auth/github')");
          loginTemplate.splice(index, 3);
          fs.writeFileSync(loginTemplateFile, loginTemplate.join(os.EOL));
  
          // views/account/profile.jade
          index = profileTemplate.indexOf('  if user.github');
          profileTemplate.splice(index - 1, 5);
          fs.writeFileSync(profileTemplateFile, profileTemplate.join(os.EOL));
  
          // models/User.js
          index = userModel.indexOf('  github: String,');
          userModel.splice(index, 1);
          fs.writeFileSync(userModelFile, userModel.join(os.EOL));
  
          // Remove GitHub from app.js
          index = app.indexOf("app.get('/auth/github', passport.authenticate('github'));");
          app.splice(index, 4);
          fs.writeFileSync(appFile, app.join(os.EOL));
  
          console.log('✗ GitHub authentication has been removed.'.error);
        }
  
        ///////////////////////////
        // Google Authentication //
        ///////////////////////////
  
        var googleRoutes = M(function() {
          /***
          app.get('/auth/google', passport.authenticate('google', { scope: 'profile email' }));
          app.get('/auth/google/callback', passport.authenticate('google', { failureRedirect: '/login' }), function(req, res) {
            res.redirect(req.session.returnTo || '/');
          });
          ***/
        });
        var googleStrategyRequire = "var GoogleStrategy = require('passport-google-oauth').OAuth2Strategy;";
        var googleStrategy = M(function() {
          /***
          // Sign in with Google.
  
          passport.use(new GoogleStrategy(secrets.google, function(req, accessToken, refreshToken, profile, done) {
            if (req.user) {
              User.findOne({ $or: [{ google: profile.id }, { email: profile.email }] }, function(err, existingUser) {
                if (existingUser) {
                  req.flash('errors', { msg: 'There is already a Google account that belongs to you. Sign in with that account or delete it, then link it with your current account.' });
                  done(err);
                } else {
                  User.findById(req.user.id, function(err, user) {
                    user.google = profile.id;
                    user.tokens.push({ kind: 'google', accessToken: accessToken });
                    user.profile.name = user.profile.name || profile.displayName;
                    user.profile.gender = user.profile.gender || profile._json.gender;
                    user.profile.picture = user.profile.picture || profile._json.picture;
                    user.save(function(err) {
                      req.flash('info', { msg: 'Google account has been linked.' });
                      done(err, user);
                    });
                  });
                }
              });
            } else {
              User.findOne({ google: profile.id }, function(err, existingUser) {
                if (existingUser) return done(null, existingUser);
                User.findOne({ email: profile._json.email }, function(err, existingEmailUser) {
                  if (existingEmailUser) {
                    req.flash('errors', { msg: 'There is already an account using this email address. Sign in to that account and link it with Google manually from Account Settings.' });
                    done(err);
                  } else {
                    var user = new User();
                    user.email = profile._json.email;
                    user.google = profile.id;
                    user.tokens.push({ kind: 'google', accessToken: accessToken });
                    user.profile.name = profile.displayName;
                    user.profile.gender = profile._json.gender;
                    user.profile.picture = profile._json.picture;
                    user.save(function(err) {
                      done(err, user);
                    });
                  }
                });
              });
            }
           }));
  
           ***/
        });
  
        var googleButton = M(function() {
          /***
                a.btn.btn-block.btn-google-plus.btn-social(href='/auth/google')
                  i.fa.fa-google-plus
                  | Sign in with Google
          ***/
        });
        var googleLinkUnlink = M(function() {
          /***
  
            if user.google
              p: a.text-danger(href='/account/unlink/google') Unlink your Google account
            else
              p: a(href='/auth/google') Link your Google account
          ***/
        });
        var googleModel = '  google: String,';
  
        if (_.contains(answer.auth, 'Google')) {
          if (passportConfig.indexOf(googleStrategyRequire) < 0) {
  
            // Add Google to config/passport.js
            index = passportConfig.indexOf("var passport = require('passport');");
            passportConfig.splice(index + 1, 0, googleStrategyRequire);
            index = passportConfig.indexOf('passport.deserializeUser(function(id, done) {');
            passportConfig.splice(index + 6, 0, googleStrategy);
            fs.writeFileSync(passportConfigFile, passportConfig.join(os.EOL));
  
            // Add Google to views/account/login.jade
            loginTemplate.push(googleButton);
            fs.writeFileSync(loginTemplateFile, loginTemplate.join(os.EOL));
  
            // Add Google to views/account/profile.jade
            index = profileTemplate.indexOf('    h3 Linked Accounts');
            profileTemplate.splice(index + 1, 0, googleLinkUnlink);
            fs.writeFileSync(profileTemplateFile, profileTemplate.join(os.EOL));
  
            // Add Google to models/User.js
            index = userModel.indexOf('  tokens: Array,');
            userModel.splice(index - 1, 0, googleModel);
            fs.writeFileSync(userModelFile, userModel.join(os.EOL));
  
            // Add Google to app.js
            index = app.indexOf(' * OAuth routes for sign-in.');
            app.splice(index + 3, 0, googleRoutes);
            fs.writeFileSync(appFile, app.join(os.EOL));
  
            console.log('✓ Google authentication has been added.'.info);
          } else {
            console.log('✓ Google authentication is already active.'.data);
          }
        } else {
  
          // Remove Google from config/passport.js
          index = passportConfig.indexOf(googleStrategyRequire);
          passportConfig.splice(index, 1);
          index = passportConfig.indexOf('// Sign in with Google.');
          passportConfig.splice(index, 46);
          fs.writeFileSync(passportConfigFile, passportConfig.join(os.EOL));
  
          // Remove Google from views/account/login.jade
          index = loginTemplate.indexOf("      a.btn.btn-block.btn-google-plus.btn-social(href='/auth/google')");
          loginTemplate.splice(index, 3);
          fs.writeFileSync(loginTemplateFile, loginTemplate.join(os.EOL));
  
          // Remove Google from views/account/profile.jade
          index = profileTemplate.indexOf('  if user.google');
          profileTemplate.splice(index - 1, 5);
          fs.writeFileSync(profileTemplateFile, profileTemplate.join(os.EOL));
  
          // Remove Google from models/User.js
          index = userModel.indexOf('  google: String,');
          userModel.splice(index, 1);
          fs.writeFileSync(userModelFile, userModel.join(os.EOL));
  
          // Remove Google from app.js
          index = app.indexOf("app.get('/auth/google', passport.authenticate('google', { scope: 'profile email' }));");
          app.splice(index, 4);
          fs.writeFileSync(appFile, app.join(os.EOL));
  
          console.log('✗ Google authentication has been removed.'.error);
        }
  
        ////////////////////////////
        // Twitter Authentication //
        ////////////////////////////
  
        var twitterRoutes = M(function() {
          /***
          app.get('/auth/twitter', passport.authenticate('twitter'));
          app.get('/auth/twitter/callback', passport.authenticate('twitter', { failureRedirect: '/login' }), function(req, res) {
            res.redirect(req.session.returnTo || '/');
          });
          ***/
        });
        var twitterStrategyRequire = "var TwitterStrategy = require('passport-twitter').Strategy;";
        var twitterStrategy = M(function() {
          /***
          // Sign in with Twitter.
  
          passport.use(new TwitterStrategy(secrets.twitter, function(req, accessToken, tokenSecret, profile, done) {
            if (req.user) {
              User.findOne({ twitter: profile.id }, function(err, existingUser) {
                if (existingUser) {
                  req.flash('errors', { msg: 'There is already a Twitter account that belongs to you. Sign in with that account or delete it, then link it with your current account.' });
                  done(err);
                } else {
                  User.findById(req.user.id, function(err, user) {
                    user.twitter = profile.id;
                    user.tokens.push({ kind: 'twitter', accessToken: accessToken, tokenSecret: tokenSecret });
                    user.profile.name = user.profile.name || profile.displayName;
                    user.profile.location = user.profile.location || profile._json.location;
                    user.profile.picture = user.profile.picture || profile._json.profile_image_url;
                    user.save(function(err) {
                      req.flash('info', { msg: 'Twitter account has been linked.' });
                      done(err, user);
                    });
                  });
                }
              });
            } else {
              User.findOne({ twitter: profile.id }, function(err, existingUser) {
                if (existingUser) return done(null, existingUser);
                var user = new User();
                // Twitter will not provide an email address.  Period.
                // But a person’s twitter username is guaranteed to be unique
                // so we can "fake" a twitter email address as follows:
                user.email = profile.username + "@twitter.com";
                user.twitter = profile.id;
                user.tokens.push({ kind: 'twitter', accessToken: accessToken, tokenSecret: tokenSecret });
                user.profile.name = profile.displayName;
                user.profile.location = profile._json.location;
                user.profile.picture = profile._json.profile_image_url;
                user.save(function(err) {
                  done(err, user);
                });
              });
            }
          }));
          ***/
        });
  
        var twitterButton = M(function() {
          /***
                 a.btn.btn-block.btn-twitter-plus.btn-social(href='/auth/twitter')
                   i.fa.fa-twitter
                   | Sign in with Twitter
           ***/
        });
        var twitterLinkUnlink = M(function() {
          /***
  
            if user.twitter
              p: a.text-danger(href='/account/unlink/twitter') Unlink your Twitter account
            else
              p: a(href='/auth/twitter') Link your Twitter account
          ***/
        });
        var twitterModel = '  twitter: String,';
  
        if (_.contains(answer.auth, 'Twitter')) {
          if (passportConfig.indexOf(twitterStrategyRequire) < 0) {
  
            // config/passport.js
            index = passportConfig.indexOf("var passport = require('passport');");
            passportConfig.splice(index + 1, 0, twitterStrategyRequire);
            index = passportConfig.indexOf('passport.deserializeUser(function(id, done) {');
            passportConfig.splice(index + 6, 0, twitterStrategy);
            fs.writeFileSync(passportConfigFile, passportConfig.join(os.EOL));
  
            // views/account/login.jade
            loginTemplate.push(twitterButton);
            fs.writeFileSync(loginTemplateFile, loginTemplate.join(os.EOL));
  
            // views/account/profile.jade
            index = profileTemplate.indexOf('    h3 Linked Accounts');
            profileTemplate.splice(index + 1, 0, twitterLinkUnlink);
            fs.writeFileSync(profileTemplateFile, profileTemplate.join(os.EOL));
  
            // models/User.js
            index = userModel.indexOf('  tokens: Array,');
            userModel.splice(index - 1, 0, twitterModel);
            fs.writeFileSync(userModelFile, userModel.join(os.EOL));
  
            // Add Twitter to app.js
            index = app.indexOf(' * OAuth routes for sign-in.');
            app.splice(index + 3, 0, twitterRoutes);
            fs.writeFileSync(appFile, app.join(os.EOL));
  
            console.log('✓ Twitter authentication has been added.'.info);
          } else {
            console.log('✓ Twitter authentication is already active.'.data);
          }
        } else {
  
          // Remove Twitter from config/passport.js
          index = passportConfig.indexOf(twitterStrategyRequire);
          passportConfig.splice(index, 1);
          index = passportConfig.indexOf('// Sign in with Twitter.');
          passportConfig.splice(index, 43);
          fs.writeFileSync(passportConfigFile, passportConfig.join(os.EOL));
  
          // Remove Twitter from views/account/login.jade
          index = loginTemplate.indexOf("      a.btn.btn-block.btn-twitter.btn-social(href='/auth/twitter')");
          loginTemplate.splice(index, 3);
          fs.writeFileSync(loginTemplateFile, loginTemplate.join(os.EOL));
  
          // Remove Twitter from views/account/profile.jade
          index = profileTemplate.indexOf('  if user.twitter');
          profileTemplate.splice(index - 1, 5);
          fs.writeFileSync(profileTemplateFile, profileTemplate.join(os.EOL));
  
          // Remove Twitter from models/User.js
          index = userModel.indexOf('  twitter: String,');
          userModel.splice(index, 1);
          fs.writeFileSync(userModelFile, userModel.join(os.EOL));
  
          // Remove Twitter from app.js
          index = app.indexOf("app.get('/auth/twitter', passport.authenticate('twitter'));");
          app.splice(index, 4);
          fs.writeFileSync(appFile, app.join(os.EOL));
  
          console.log('✗ Twitter authentication has been removed.'.error);
        }
  
        /////////////////////////////
        // LinkedIn Authentication //
        /////////////////////////////
  
        var linkedinRoutes = M(function() {
          /***
          app.get('/auth/linkedin', passport.authenticate('linkedin', { state: 'SOME STATE' }));
          app.get('/auth/linkedin/callback', passport.authenticate('linkedin', { failureRedirect: '/login' }), function(req, res) {
            res.redirect(req.session.returnTo || '/');
          });
          ***/
        });
        var linkedinStrategyRequire = "var LinkedInStrategy = require('passport-linkedin-oauth2').Strategy;";
        var linkedinStrategy = M(function() {
          /***
          // Sign in with LinkedIn.
  
          passport.use(new LinkedInStrategy(secrets.linkedin, function(req, accessToken, refreshToken, profile, done) {
            if (req.user) {
              User.findOne({ $or: [
                { linkedin: profile.id },
                { email: profile._json.emailAddress }
              ] }, function(err, existingUser) {
                if (existingUser) {
                  req.flash('errors', { msg: 'There is already a LinkedIn account that belongs to you. Sign in with that account or delete it, then link it with your current account.' });
                  done(err);
                } else {
                  User.findById(req.user.id, function(err, user) {
                    user.linkedin = profile.id;
                    user.tokens.push({ kind: 'linkedin', accessToken: accessToken });
                    user.profile.name = user.profile.name || profile.displayName;
                    user.profile.location = user.profile.location || profile._json.location.name;
                    user.profile.picture = user.profile.picture || profile._json.pictureUrl;
                    user.profile.website = user.profile.website || profile._json.publicProfileUrl;
                    user.save(function(err) {
                      req.flash('info', { msg: 'LinkedIn account has been linked.' });
                      done(err, user);
                    });
                  });
                }
              });
            } else {
              User.findOne({ linkedin: profile.id }, function(err, existingUser) {
                if (existingUser) return done(null, existingUser);
                User.findOne({ email: profile._json.emailAddress }, function(err, existingEmailUser) {
                  if (existingEmailUser) {
                    req.flash('errors', { msg: 'There is already an account using this email address. Sign in to that account and link it with LinkedIn manually from Account Settings.' });
                    done(err);
                  } else {
                    var user = new User();
                    user.linkedin = profile.id;
                    user.tokens.push({ kind: 'linkedin', accessToken: accessToken });
                    user.email = profile._json.emailAddress;
                    user.profile.name = profile.displayName;
                    user.profile.location = profile._json.location.name;
                    user.profile.picture = profile._json.pictureUrl;
                    user.profile.website = profile._json.publicProfileUrl;
                    user.save(function(err) {
                      done(err, user);
                    });
                  }
                });
              });
            }
          }));
          ***/
        });
  
        var linkedinButton = M(function() {
          /***
                a.btn.btn-block.btn-linkedin.btn-social(href='/auth/linkedin')
                  i.fa.fa-linkedin
                  | Sign in with LinkedIn
          ***/
        });
        var linkedinLinkUnlink = M(function() {
          /***
  
            if user.linkedin
              p: a.text-danger(href='/account/unlink/linkedin') Unlink your LinkedIn account
            else
              p: a(href='/auth/linkedin') Link your LinkedIn account
          ***/
        });
        var linkedinModel = '  linkedin: String,';
  
        if (_.contains(answer.auth, 'LinkedIn')) {
          if (passportConfig.indexOf(linkedinStrategyRequire) < 0) {
  
            // Add LinkedIn to passport.js
            index = passportConfig.indexOf("var passport = require('passport');");
            passportConfig.splice(index + 1, 0, linkedinStrategyRequire);
            index = passportConfig.indexOf('passport.deserializeUser(function(id, done) {');
            passportConfig.splice(index + 6, 0, linkedinStrategy);
            fs.writeFileSync(passportConfigFile, passportConfig.join(os.EOL));
  
            // Add LinkedIn to login.jade
            loginTemplate.push(linkedinButton);
            fs.writeFileSync(loginTemplateFile, loginTemplate.join(os.EOL));
  
            // Add LinkedIn to profile.jade
            index = profileTemplate.indexOf('    h3 Linked Accounts');
            profileTemplate.splice(index + 1, 0, linkedinLinkUnlink);
            fs.writeFileSync(profileTemplateFile, profileTemplate.join(os.EOL));
  
            // Add LinkedIn to models/User.js
            index = userModel.indexOf('  tokens: Array,');
            userModel.splice(index - 1, 0, linkedinModel);
            fs.writeFileSync(userModelFile, userModel.join(os.EOL));
  
            // Add LinkedIn to app.js
            index = app.indexOf(' * OAuth routes for sign-in.');
            app.splice(index + 3, 0, linkedinRoutes);
            fs.writeFileSync(appFile, app.join(os.EOL));
  
            console.log('✓ LinkedIn authentication has been added.'.info);
          } else {
            console.log('✓ LinkedIn authentication is already active.'.data);
          }
        } else {
  
          // Check if we have LinkedIn authentication to begin with.
          if (passportConfig.indexOf(linkedinStrategyRequire) < 0) return;
  
          // Removed LinkedIn from passport.js
          index = passportConfig.indexOf(linkedinStrategyRequire);
          passportConfig.splice(index, 1);
          index = passportConfig.indexOf('// Sign in with LinkedIn.');
          passportConfig.splice(index, 51);
          fs.writeFileSync(passportConfigFile, passportConfig.join(os.EOL));
  
          // Remove LinkedIn from login.jade
          index = loginTemplate.indexOf("      a.btn.btn-block.btn-linkedin.btn-social(href='/auth/linkedin')");
          loginTemplate.splice(index, 3);
          fs.writeFileSync(loginTemplateFile, loginTemplate.join(os.EOL));
  
          // Remove LinkedIn from profile.jade
          index = profileTemplate.indexOf('  if user.linkedin');
          profileTemplate.splice(index - 1, 5);
          fs.writeFileSync(profileTemplateFile, profileTemplate.join(os.EOL));
  
          // Remove LinkedIn from app.js
          index = app.indexOf("app.get('/auth/linkedin', passport.authenticate('linkedin', { state: 'SOME STATE' }));");
          app.splice(index, 4);
          fs.writeFileSync(appFile, app.join(os.EOL));
  
          // Remove LinkedIn from User.js
          index = userModel.indexOf('  linkedin: String,');
          userModel.splice(index, 1);
          fs.writeFileSync(userModelFile, userModel.join(os.EOL));
  
          console.log('✗ LinkedIn authentication has been removed.'.error);
        }
  
        //////////////////////////////
        // Instagram Authentication //
        //////////////////////////////
  
        var instagramRoutes = M(function() {
          /***
          app.get('/auth/instagram', passport.authenticate('instagram'));
          app.get('/auth/instagram/callback', passport.authenticate('instagram', { failureRedirect: '/login' }), function(req, res) {
            res.redirect(req.session.returnTo || '/');
          });
          ***/
        });
        var instagramSecrets = M(function() {
          /***
             instagram: {
               clientID: process.env.INSTAGRAM_ID || 'Your Client ID',
               clientSecret: process.env.INSTAGRAM_SECRET || 'Your Client Secret',
               callbackURL: '/auth/instagram/callback',
               passReqToCallback: true
             },
  
           ***/
        });
        var instagramStrategyRequire = "var InstagramStrategy = require('passport-instagram').Strategy;";
        var instagramStrategy = M(function() {
          /***
          // Sign in with Instagram.
  
          passport.use(new InstagramStrategy(secrets.instagram,function(req, accessToken, refreshToken, profile, done) {
            if (req.user) {
              User.findOne({ $or: [{ instagram: profile.id }, { email: profile.email }] }, function(err, existingUser) {
                if (existingUser) {
                  req.flash('errors', { msg: 'There is already an Instagram account that belongs to you. Sign in with that account or delete it, then link it with your current account.' });
                  done(err);
                } else {
                  User.findById(req.user.id, function(err, user) {
                    user.instagram = profile.id;
                    user.tokens.push({ kind: 'instagram', accessToken: accessToken });
                    user.profile.name = user.profile.name || profile.displayName;
                    user.profile.picture = user.profile.picture || profile._json.data.profile_picture;
                    user.profile.website = user.profile.website || profile._json.data.website;
                    user.save(function(err) {
                      req.flash('info', { msg: 'Instagram account has been linked.' });
                      done(err, user);
                    });
                  });
                }
              });
            } else {
              User.findOne({ instagram: profile.id }, function(err, existingUser) {
                if (existingUser) return done(null, existingUser);
  
                var user = new User();
                user.instagram = profile.id;
                user.tokens.push({ kind: 'instagram', accessToken: accessToken });
                user.profile.name = profile.displayName;
                user.email = '';
                user.profile.website = profile._json.data.website;
                user.profile.picture = profile._json.data.profile_picture;
                user.save(function(err) {
                  done(err, user);
                });
              });
            }
          }));
  
          ***/
        });
  
        var instagramButton = M(function() {
          /***
                a.btn.btn-block.btn-instagram.btn-social(href='/auth/instagram')
                  i.fa.fa-instagram
                  | Sign in with Instagram
          ***/
        });
        var instagramLinkUnlink = M(function() {
          /***
  
            if user.instagram
              p: a.text-danger(href='/account/unlink/instagram') Unlink your Instagram account
            else
              p: a(href='/auth/instagram') Link your Instagram account
          ***/
        });
        var instagramModel = '  instagram: String,';
  
        if (_.contains(answer.auth, 'Instagram')) {
  
          if (passportConfig.indexOf(instagramStrategyRequire) < 0) {
  
            // Add Instagram to passport.js
            index = passportConfig.indexOf("var passport = require('passport');");
            passportConfig.splice(index + 1, 0, instagramStrategyRequire);
            index = passportConfig.indexOf('passport.deserializeUser(function(id, done) {');
            passportConfig.splice(index + 6, 0, instagramStrategy);
            fs.writeFileSync(passportConfigFile, passportConfig.join(os.EOL));
  
            // Add Instagram to login.jade
            loginTemplate.push(instagramButton);
            fs.writeFileSync(loginTemplateFile, loginTemplate.join(os.EOL));
  
            // Add Instagram to profile.jade
            index = profileTemplate.indexOf('    h3 Linked Accounts');
            profileTemplate.splice(index + 1, 0, instagramLinkUnlink);
            fs.writeFileSync(profileTemplateFile, profileTemplate.join(os.EOL));
  
            // Add Instagram to User.js
            index = userModel.indexOf('  tokens: Array,');
            userModel.splice(index - 1, 0, instagramModel);
            fs.writeFileSync(userModelFile, userModel.join(os.EOL));
  
            // Add Instagram to app.js
            index = app.indexOf(' * OAuth routes for sign-in.');
            app.splice(index + 3, 0, instagramRoutes);
            fs.writeFileSync(appFile, app.join(os.EOL));
  
            // Add Instagram to secrets.js
            index = secrets.indexOf('module.exports = {');
            secrets.splice(index + 1, 0, instagramSecrets);
            fs.writeFileSync(secretsFile, secrets.join(os.EOL));
  
            console.log('✓ Instagram authentication has been added.'.info);
          } else {
            console.log('✓ Instagram authentication is already active.'.data);
          }
        } else {
  
          if (passportConfig.indexOf(instagramStrategyRequire) < 0) return;
  
          // Remove Instagram from passport.js
          index = passportConfig.indexOf(instagramStrategyRequire);
          passportConfig.splice(index, 1);
          index = passportConfig.indexOf('// Sign in with Instagram.');
          passportConfig.splice(index, 40);
          fs.writeFileSync(passportConfigFile, passportConfig.join(os.EOL));
  
          // Remove Instagram from login.jade
          index = loginTemplate.indexOf("      a.btn.btn-block.btn-instagram.btn-social(href='/auth/instagram')");
          loginTemplate.splice(index, 3);
          fs.writeFileSync(loginTemplateFile, loginTemplate.join(os.EOL));
  
          // Remove Instagram from profile.jade
          index = profileTemplate.indexOf('  if user.instagram');
          profileTemplate.splice(index - 1, 5);
          fs.writeFileSync(profileTemplateFile, profileTemplate.join(os.EOL));
  
          // Remove Instagram from app.js
          index = app.indexOf("app.get('/auth/instagram', passport.authenticate('instagram'));");
          app.splice(index, 4);
          fs.writeFileSync(appFile, app.join(os.EOL));
  
          // Remove Instagram from secrets.js
          index = secrets.indexOf('  instagram: {');
          secrets.splice(index, 7);
          fs.writeFileSync(secretsFile, secrets.join(os.EOL));
  
          // Remove Instagram from User.js
          index = userModel.indexOf('  instagram: String,');
          userModel.splice(index, 1);
          fs.writeFileSync(userModelFile, userModel.join(os.EOL));
  
          console.log('✗ Instagram authentication has been removed.'.error);
        }
      });
    }
  });