app.js

// This requires the necessary libraries for the webapp.
// (1) express - this provides the express web framework
// (2) handlebars - this provides the handlebars templating framework
var express    = require('express');
var handlebars = require('express-handlebars');

// The body parser is used to parse the body of an HTTP request.
var bodyParser = require('body-parser');

// Require session library.
var session    = require('express-session');

// Require flash library.
var flash      = require('connect-flash');

// The cookie parser is used to parse cookies in an HTTP header.
var cookieParser = require('cookie-parser');

var fs = require('fs');

var multer = require('multer');

var upload = multer({ dest: 'public/uploads' });

//////////////////////////////////////////////////////////////////////
///// Express App Setup //////////////////////////////////////////////
//////////////////////////////////////////////////////////////////////

// The express library is a simple function. When you invoke this
// function it returns an express web application that you build from.
var app = express();

var router = express.Router();



// This will set an "application variable". An application variable is
// a variable that can be retrieved from your app later on. It is
// simply a key/value mapping. In this case, we are mapping the key
// 'port' to a port number. The port number will either be what you
// set for PORT as an environment variable (google this if you do not
// know what an evironment variable is) or port 3000.
app.set('port', process.env.PORT || 3000);

// This does the setup for handlebars. It first creates a new
// handlebars object giving it the default layout. This indicates
// that the default layout is called main.js in the views/layouts
// directory. We then set the app's view engine to 'handlebars' - this
// lets your express app know what the view engine is. We then set an
// app variable 'view engine' to 'handlebars'. This is mostly boiler
// plate so you need not worry about the details.
var view = handlebars.create({ defaultLayout: 'main' });
app.engine('handlebars', view.engine);
app.set('view engine', 'handlebars');

// This does the setup for static file serving. It uses express'
// static middleware to look for files in /public if no other route
// matches. We use the __dirname special variable which indicates the
// directory this server is running in and append it to '/public'.
app.use(express.static(__dirname + '/public'));

// The `testmw` function represents out testing middleware. We use
// this in our views to conditionally include the Mocha and Chai
// testing framework as well as our own tests. Because this is a
// middleware function it expects to receive the request object
// (`req`), response object (`res`), and `next` function as arguments.
// The `next` function is used to continue processing the request
// with subsequent routes.
function testmw(req, res, next) {
  // This checks the 'env' application variable to determine if we are
  // in "production" mode. An application is in "production" mode if
  // it is actually deployed. This can be set by the NODE_ENV
  // environment variable. It also checks to see if the request has
  // given a `test` querystring parameter, such as
  // http://localhost:3000/about?test=1. If the route has that set
  // then showTests will be set to a "truthy" value. We can then
  // use that in our handlebars views to conditionally include tests.
  res.locals.showTests = app.get('env') !== 'production' &&
                         req.query.test;
  // Passes the request to the next route handler.
  next();
}

// This adds our testing middleware to the express app.
app.use(testmw);

// Body Parser:
app.use(bodyParser.urlencoded({ extended: false }));
app.use(bodyParser.json());

// Cookie Parser:
app.use(cookieParser());

// Session Support:
app.use(session({
  secret: 'octocat',
  // Both of the options below are deprecated, but should be false
  // until removed from the library - sometimes, the reality of
  // libraries can be rather annoying!
  saveUninitialized: false, // does not save uninitialized session.
  resave: false             // does not save session if not modified.
}));

// Use Flash
app.use(flash());

//////////////////////////////////////////////////////////////////////
///// User Defined Routes ////////////////////////////////////////////
//////////////////////////////////////////////////////////////////////
var team = require('./lib/team');
var database = require('./lib/database');
var authentication = require('./routes/authentication');
var course = require('./routes/class');
var authenticateLogin = authentication.authenticateLogin;
var authenticateAdmin = authentication.authenticateAdmin;

// Setup sockets.io
var server = require('http').Server(app);
var io = require('socket.io')(server);

io.on('connection', (socket) => {

  function getSocketCollisionId(conv_id, from_class) {
    return 2 * conv_id + (from_class ? 1 : 0);
  }

  socket.on('subscribe', (conv_id, from_class) => {
    socket.join(getSocketCollisionId(conv_id, from_class));
  });

  socket.on('send_private_message', (data) => {
    // Display the message to clients in this conversation.
    var msg_data = {from_user: data.sender_info.user_id,
                    fname: data.sender_info.fname,
                    lname: data.sender_info.lname,
                    message: data.msg};
    io.sockets.in(getSocketCollisionId(data.conv_id, false)).emit('display_private_message', msg_data, data.conv_id);

    // Save the message in the database.
    database.createNewMessage(data.sender_info.user_id, data.conv_id, data.msg, (err, success) => {
      if (err) {
        console.log('Error saving message: ' + err);
      }
    });
  });

  socket.on('send_class_message', (data) => {
    // Display the message to clients in this conversation.
    var msg_data = {from_user: data.sender_info.user_id,
      fname: data.sender_info.fname,
      lname: data.sender_info.lname,
      message: data.msg};
    io.sockets.in(getSocketCollisionId(data.course_id, true)).emit('display_class_message', msg_data, data.course_id);

    // Save the message in the database.
    database.createNewClassMessage(data.sender_info.user_id, data.course_id, data.msg, (err, success) => {
      if (err) {
        console.log('Error saving message: ' + err);
      }
    });
  });

  socket.on('disconnect', () => {
    // no-op
  });
});

// Routes involving user login and registration.
app.use('/auth', require('./routes/authentication').router);

//Routes involving classes
app.use('/course', require('./routes/class').router);

app.post('/reportcontent',function(req, res){
    var userId = req.session.user.id;
    console.log(req.body);
    var formData = req.body;
    //If the message hasn't yet been assigned an id we have to look it up in the db using the message and author
    //It is faster to not wait for an id to be assigned than to feed the message to the database then display it.
    if(formData.reported_message !== '0') {
        database.reportContent(userId, formData.explanation, formData.reported_user, formData.reported_message, function (err) {
            if (err) {
                console.log(err);
                res.end();
            } else {
                res.redirect("/class?cid=" + req.body.course_id);
                res.end();
            }

        });
    }
    else
    {
        database.getClassMessageId(formData.reported_user, formData.message_content, function(err, messageIds){
            if(err){
                console.log(err);
            }else{

                database.reportContent(userId, formData.explanation, formData.reported_user, messageIds[0].id, function(){
                    if (err) {
                        console.log(err);
                        res.end();
                    } else {
                        res.redirect("/class?cid=" + req.body.course_id);
                        res.end();
                    }
                });
            }
        });
    }
});


app.post('/addevent', function (req, res) {
  var calendarDate = req.body.date;
  var title = req.body.name;
  var description = req.body.description;
  var course_id = req.body.course_id;

  database.addCalendarEvent(course_id, calendarDate, title, description, (err, results)=> {
    if(err){
      console.log(err);
    }else{
      res.redirect("/class?cid=" + course_id);
      res.end();
    }
  });
});

/*
This allows users to uploads a profile picture to their profile
Relies on a library called multer which takes in form data files
 */
app.post('/upload', upload.single('photo'), function (req, res, next) {
    var userId = req.session.user.id;

    console.log(req.file);

    if(typeof req.file === 'undefined'){
        //maybe add logic here to do something
    }else {

        var imageName = req.file.originalname;

        if (!imageName) {

            console.log("There was an error");
            res.redirect("/");
            res.end();

        } else {

            var newPath = req.file.path;

            fs.readFile(newPath, function (err, data) {

                //Saves the path of the picture in the database so it can be found when a profile is loaded
                database.saveProfilePictureUrl('/uploads/' + req.file.filename, userId, function () {
                    console.log('saved path successfully.');
                    res.redirect('back');
                });

                /// write file to uploads folder
                fs.writeFile(newPath, data, function (err) {

                });
            });
        }
    }
});

/*
Saves biography of the user's profile
 */
app.post('/savebio',(req,res) => {
    var userId = req.session.user.id;
    var body = req.body;
    var bioText = body['val'];

    database.saveBioData(userId, bioText, function(err){
        console.log(err);
    });
});

/*
Saves activities of the user's profile
 */
app.post('/saveact',(req,res) => {
    var userId = req.session.user.id;
    var body = req.body;
    var activities = body['val'];

    database.saveActivitesData(userId, activities, function(err){
        console.log(err);
    });
});

app.post('/savegrad',(req,res) => {
    var userId = req.session.user.id;
    var body = req.body;
    var gradYear = body['val'];

    database.saveGraduationYearData(userId, gradYear, function(err){
        console.log(err);
    });
});

app.post('/savemajor',(req,res) => {
    var userId = req.session.user.id;
    var body = req.body;
    var major = body['val'];

    database.saveMajorData(userId, major, function(err){
        console.log(err);
    });
});

app.post('/deletereportedcontent', (req,res) => {
   var body = req.body;
   var messageId = body['messageId'];

   database.deleteReportedContent(messageId, function(err, result){
      res.send({success:true});
   });
});

app.post('/allowreportedcontent', (req,res) => {
    var body = req.body;
    var messageId = body['messageId'];

    database.allowReportedContent(messageId, function(err, result){
        res.send({success:true});
    });
});

/*
This allows users to uploads a profile picture to their profile
Relies on a library called multer which takes in form data files
 */
app.post('/uploadResource', upload.single('classResource'), function (req, res, next) {
    var userId = req.session.user.id;

    console.log(req.file);
    console.log("courseID = " + req.body.course_id);
    if(typeof req.file === 'undefined'){
        //maybe add logic here to do something
    }else {

        var fileName = req.body.filetitle;

        if (!fileName) {

            console.log("There was an error -> No filename");
            res.redirect("/");
            res.end();

        } else {

            var newPath = req.file.path;

            fs.readFile(newPath, function (err, data) {



              database.saveResource('/uploads/' + req.file.filename, fileName, req.body.course_id, userId, function(err) {
                  if(err){
                    console.log(err);
                  }else{
                    /// write file to uploads folder
                      fs.writeFile(newPath, data, function (err) {
                          res.redirect("/class?cid=" + req.body.course_id);
                          res.end();
                          console.log('saved path successfully.');
                      });
                    

                  }
                    // res.redirect('back');
              });
                
            });
        }
    }
});

String.prototype.replaceAll = function(str1, str2, ignore) {
    return this.replace(new RegExp(str1.replace(/([\/\,\!\\\^\$\{\}\[\]\(\)\.\*\+\?\|\<\>\-\&])/g,"\\$&"),(ignore?"gi":"g")),(typeof(str2)=="string")?str2.replace(/\$/g,"$$$$"):str2);
};

// Home/Splash screen.
app.get('/', (req, res) => {
  // Check whether the user's logged in and online
  // If so, render the home view
  var message = req.flash('home') || '';

  if(authentication.isOnline(req.session.user)) {
    var userId = req.session.user.id;
    var data = {message: message};

    database.getUsersCalendar(userId, (err, result) => {
        if (err) {
            data.message = err;
            res.render('home', data);
        } else {
            data.calendar = result;

            database.coursesForUser(userId, (err, result) => {
                if (err) {
                    data.message = err;
                    res.render('home', data);
                } else {
                    data.courses = result;

                    for (var i = 0; i < data.calendar.length; i++) {
                        var cal = data.calendar[i].calendar_date;
                        var date = new Date(cal);
                        var dateString = date.getMonth() + 1 + "/" + date.getDate() + "/" + date.getFullYear() + "     ";
                        data.calendar[i].calendar_date = dateString;
                    }
                    data.calendar = JSON.stringify(data.calendar).replaceAll('\'', '\\\'')

                    database.getAllUserResources(userId, (err, result) => {
                        if (err) {
                          data.message = err;
                          res.render('home', data);
                        } else {
                          data.resources = result;
                          res.render('home', data);
                        }
                    });
                }


            });
        }
    });

    // Otherwise, user is not logged in
    // Render the landing view
  } else {
    res.render('landing', {
        loggedOut: true
    });
  }
});

app.get('/settings', authenticateLogin, (req, res) => {
    res.render('settings');
});

app.get('/profile', authenticateLogin, (req, res) => {
  var message = req.flash('profile') || '';
  var data = {message: message, edits: true};
  var userId = req.session.user.id;

  var goToUser = req.query.query;

  if(typeof goToUser !== 'undefined'){
      userId = goToUser;
      data.edits = false;
  }

  // Start by getting user info.
  database.getProfileInfo(userId, (err, info) => {
    if (err) {
      data.message = err;
    } else {
      data.user = info;
    }

    // Now get user courses.
    database.coursesForUser(userId, (err, courses) => {
        if(typeof goToUser !== 'undefined'){
            // Now get your own courses.
            database.coursesForUser(req.session.user.id, (err2, ownCourses) => {
                if (err || err2) {
                    data.message = err + ', ' + err2;
                } else {
                    data.courses = courses;
                    data.own_courses = ownCourses;
                }

                // Render with data.
                res.render('profile', data);
            });
        } else {
            if (err) {
                data.message = err;
            } else {
                data.courses = courses;
                data.own_courses = courses;
            }

            // Render with data.
            res.render('profile', data);
        }
    });
  });
});

app.get('/admin', authenticateAdmin, (req, res) => {
    var message = req.flash('admin') || '';
    var data = {message: message};

  database.getReportedContent(function content(err, reportedContent){

    if(err){
        data.message = err;
    }else{
        data.reported = reportedContent;
    }

    res.render('admin', data);

  });
});

app.get('/class', authenticateLogin, (req, res) => {
  //res.render('class');
  var userId = req.session.user.id;
  var initial_cid = req.query.cid || -1;

  // Get the user's enrolled courses.
  database.coursesForUser(userId, (err, courses) => {
    var data = {init_cid: initial_cid};
    if (err) {
      data.error = err;
    } else {
      data.init_course = courses[initial_cid - 1];
      data.courses = courses;

      // Fill data with sender info.
      data.sender = {id: userId, fname: req.session.user.fname, lname: req.session.user.lname};
    }

    res.render('class', data);
  });
});

app.get('/class/messages/fetch', authenticateLogin, (req, res) => {
  var course_id = req.query.course_id;
  database.getClassMessages(course_id, (err, results) => {
    var data = {};
    if (err) {
      data.error = err;
    } else {
      data.messages = results;
    }
    res.send(data);
  });
});

app.get('/class/events/fetch', authenticateLogin, (req, res) => {
  var course_id = req.query.course_id;
  database.getCalendarsForCourse(course_id, (err, results) => {
    var data = {};
    if (err) {
      data.error = err;
    } else {
      data.events = results;
    }
    res.send(data);
  });
});

app.get('/class/resources/fetch', authenticateLogin, (req, res) => {
  var course_id = req.query.course_id;
  database.getClassResources(course_id, (err, results) => {
    var data = {};
    if (err) {
      data.error = err;
    } else {
      data.resources = results;
    }
    res.send(data);
  });
});

app.get('/class/members/fetch', authenticateLogin, (req, res) => {
  var user_id = req.session.user.id;
  var course_id = req.query.course_id;

  database.getUsersForCourse(user_id, course_id, (err, results) => {
    var data = {};
    if (err) {
      data.error = err;
    } else {
      data.members = results;
    }
    res.send(data);
  });
});

app.get('/messages', authenticateLogin, (req, res) => {
  var message = req.flash('messages') || '';
  var data = {message: message, sender: req.session.user};
  var userId = req.session.user.id;

  // First get all conversations that involve us.
  database.getConversation(userId, (err, results) => {
    if (err) {
      data.message = err;
      console.log(err);
    } else {
      data.conversations = results;
    }

    // Get the user's enrolled courses.
    database.coursesForUser(userId, (err, courses) => {
        if (err) {
            data.error = err;
            console.log(err);
        } else {
            data.courses = courses;
        }
        res.render('messages', data);
    });

  });
});

app.get('/messages/fetch', authenticateLogin, (req, res) => {
  var conv_id = req.query.conv_id;
  database.getConversationMessages(conv_id, (err, results) => {
    var data = {};
    if (err) {
      data.error = err;
    } else {
      data.messages = results;
    }
    res.send(data);
  });
});

app.get('/friends/fetch', authenticateLogin, (req, res) => {
  var user_id = req.session.user.id;
  database.getPossibleFriends(user_id, (err, results) => {
    var data = {};
    if (err) {
      data.error = err;
    } else {
      data.friends = results;
    }
    res.send(data);
  });
});

app.get('/messages/new_conversation', authenticateLogin, (req, res) => {
  var friend_id = req.query.friend_id;
  var user_id = req.session.user.id;
  var data = {};

  // First make sure this conversation doesn't already exist.
  database.getConversationForBothUsers(user_id, friend_id, (err, results) => {
    if (err) {
      data.error = err;
      res.send(data);
    } else if (results.length > 0) {
      data.error = "You're already talking to this friend!";
      res.send(data);
    }

    // Now create a new conversation and return it to the view.
    else {
      database.createPrivateConversation(user_id, friend_id, (err, results) => {
        if (err) {
          data.error = err;
        } else if (results.length === 0) {
          data.error = "Something went wrong. Please try again later";
        } else {
          data.conversation = results[0];
        }
        res.send(data);
      });
    }
  });
});

app.get('/team', (req, res) => {
  var result;
  if (req.query.user) {
    // Retrieve the selected user from the query.
    result = team.one(req.query.user);
  } else {
    // No query string, show the whole team.
    result = team.all();
  }

  if (!result.success) {
    notFound404(req, res);
  } else {
    res.render('team', {
      members: result.data,
      multiple: result.multiple,
      pageTestScript: '/qa/tests-team.js'
    });
  }
});


app.get('/about', (req, res) => {
  res.render('about')
});


//////////////////////////////////////////////////////////////////////
///// Error Middleware ///////////////////////////////////////////////
//////////////////////////////////////////////////////////////////////

// A middleware function that will be invoked if no other route path
// has been matched. HTTP 404 indicates that the resource was not
// found. We set the HTTP status code in the response object to 404.
// We then render our views/404.handlebars view back to the client.
function notFound404(req, res) {
  res.status(404);
  res.render('404');
}

// A middleware function that will be invoked if there is an internal
// server error (HTTP 500). An internal server error indicates that
// a serious problem occurred in the server. When there is a serious
// problem in the server an additional `err` parameter is given. In
// our implementation here we print the stack trace of the error, set
// the response status code to 500, and render our
// views/500.handlebars view back to the client.
function internalServerError500(err, req, res, next) {
  console.error(err.stack);
  res.status(500);
  res.render('500');
}

// This adds the two middleware functions as the last two middleware
// functions. Because they are at the end they will only be invoked if
// no other route defined above does not match.
app.use(notFound404);
app.use(internalServerError500);

//////////////////////////////////////////////////////////////////////
//// Application Startup /////////////////////////////////////////////
//////////////////////////////////////////////////////////////////////

// Starts the express application up on the port specified by the
// application variable 'port' (which was set above). The second
// parameter is a function that gets invoked after the application is
// up and running.
server.listen(app.get('port'), () => {
  console.log('Express started on http://localhost:' +
              app.get('port') + '; press Ctrl-C to terminate');
});