public/javascripts/assessment.js

   1 let socket = null; //monitor answers in real time
   2
   3 if (assessment.mode == "secure" && !checkWindowSize())
   4     document.location.href= "/fullscreen";
   5
   6 function checkWindowSize()
   7 {
   8     // NOTE: temporarily accept smartphone (security hole: pretend being a smartphone on desktop browser...)
   9     if (navigator.userAgent.match(/(iPhone|iPod|iPad|Android|BlackBerry)/))
  10         return true;
  11     // 3 is arbitrary, but a small tolerance is required (e.g. in Firefox)
  12     return window.innerWidth >= screen.width-3 && window.innerHeight >= screen.height-3;
  13 }
  14
  15 new Vue({
  16     el: "#assessment",
  17     data: {
  18         assessment: assessment,
  19         answers: { }, //filled later with answering parameters
  20         student: { }, //filled later (name, password)
  21         // Stage 0: unauthenticated (number),
  22         //       1: authenticated (got a name, unvalidated)
  23         //       2: locked: password set, exam started
  24         //       3: completed
  25         //       4: show answers
  26         remainingTime: assessment.time, //integer or array
  27         stage: assessment.mode != "open" ? 0 : 1,
  28         warnMsg: "",
  29     },
  30     computed: {
  31         countdown: function() {
  32             const remainingTime = assessment.display == "one" && _.isArray(assessment.time)
  33                 ? this.remainingTime[this.answers.index]
  34                 : this.remainingTime;
  35             let seconds = remainingTime % 60;
  36             let minutes = Math.floor(remainingTime / 60);
  37             return this.padWithZero(minutes) + ":" + this.padWithZero(seconds);
  38         },
  39     },
  40     mounted: function() {
  41         $(".modal").modal();
  42         if (["exam","open"].includes(assessment.mode))
  43             return;
  44         window.addEventListener("blur", () => {
  45             if (this.stage != 2)
  46                 return;
  47             if (assessment.mode == "secure")
  48             {
  49                 this.sendAnswer();
  50                 document.location.href= "/noblur";
  51             }
  52             else //"watch" mode
  53                 socket.emit(message.studentBlur, {number:this.student.number});
  54         }, false);
  55         if (assessment.mode == "watch")
  56         {
  57             window.addEventListener("focus", () => {
  58                 if (this.stage != 2)
  59                     return;
  60                 socket.emit(message.studentFocus, {number:this.student.number});
  61             }, false);
  62         }
  63         window.addEventListener("resize", e => {
  64             if (this.stage != 2)
  65                 return;
  66             if (assessment.mode == "secure")
  67             {
  68                 this.sendAnswer();
  69                 document.location.href = "/fullscreen";
  70             }
  71             else //"watch" mode
  72             {
  73                 if (checkWindowSize())
  74                     socket.emit(message.studentFullscreen, {number:this.student.number});
  75                 else
  76                     socket.emit(message.studentResize, {number:this.student.number});
  77             }
  78         }, false);
  79     },
  80     methods: {
  81         // In case of AJAX errors (not blur-ing)
  82         showWarning: function(message) {
  83             this.warnMsg = message;
  84             $("#warning").modal("open");
  85         },
  86         padWithZero: function(x) {
  87             if (x < 10)
  88                 return "0" + x;
  89             return x;
  90         },
  91         // stage 0 --> 1
  92         getStudent: function() {
  93             $.ajax("/get/student", {
  94                 method: "GET",
  95                 data: {
  96                     number: this.student.number,
  97                     cid: assessment.cid,
  98                 },
  99                 dataType: "json",
 100                 success: s => {
 101                     if (!!s.errmsg)
 102                         return this.showWarning(s.errmsg);
 103                     this.stage = 1;
 104                     this.student = s.student;
 105                     Vue.nextTick( () => { Materialize.updateTextFields(); });
 106                 },
 107             });
 108         },
 109         // stage 1 --> 0
 110         cancelStudent: function() {
 111             this.stage = 0;
 112         },
 113         // stage 1 --> 2 (get all questions, set password)
 114         startAssessment: function() {
 115             let initializeStage2 = paper => {
 116                 $("#leftButton, #rightButton").hide();
 117                 // Initialize structured answer(s) based on questions type and nesting (TODO: more general)
 118
 119                 // if display == "all" getQuestionS
 120                 // otherwise get first question
 121
 122
 123                 if (!!questions)
 124                     assessment.questions = questions;
 125                 this.answers.inputs = [ ];
 126                 for (let q of assessment.questions)
 127                     this.answers.inputs.push( _(q.options.length).times( _.constant(false) ) );
 128                 if (!paper)
 129                 {
 130                     this.answers.indices = assessment.fixed
 131                         ? _.range(assessment.questions.length)
 132                         : _.shuffle( _.range(assessment.questions.length) );
 133                 }
 134                 else
 135                 {
 136                     // Resuming
 137                     let indices = paper.inputs.map( input => { return input.index; });
 138                     let remainingIndices = _.difference( _.range(assessment.questions.length).map(String), indices );
 139                     this.answers.indices = indices.concat( _.shuffle(remainingIndices) );
 140                 }
 141
 142
 143
 144
 145
 146
 147
 148                 if (assessment.time > 0)
 149                 {
 150
 151 // TODO: distinguish total exam time AND question time
 152
 153                     const deltaTime = !!paper ? Date.now() - paper.startTime : 0;
 154                     this.remainingTime = assessment.time * 60 - Math.round(deltaTime / 1000);
 155                     this.runTimer();
 156                 }
 157
 158
 159                 this.answers.index = !!paper ? paper.inputs.length : 0;
 160                 this.answers.displayAll = assessment.display == "all";
 161                 this.answers.showSolution = false;
 162                 this.stage = 2;
 163             };
 164             if (assessment.mode == "open")
 165                 return initializeStage2();
 166             $.ajax("/start/assessment", {
 167                 method: "GET",
 168                 data: {
 169                     number: this.student.number,
 170                     aid: assessment._id
 171                 },
 172                 dataType: "json",
 173                 success: s => {
 174                     if (!!s.errmsg)
 175                         return this.showWarning(s.errmsg);
 176                     if (!!s.paper)
 177                     {
 178                         // Resuming: receive stored answers + startTime
 179                         this.student.password = s.paper.password;
 180                         this.answers.inputs = s.paper.inputs.map( inp => { return inp.input; });
 181                     }
 182                     else
 183                     {
 184                         this.student.password = s.password;
 185                         // Got password: students answers locked to this page until potential teacher
 186                         // action (power failure, computer down, ...)
 187                     }
 188                     socket = io.connect("/", {
 189                         query: "aid=" + assessment._id + "&number=" + this.student.number + "&password=" + this.student.password
 190                     });
 191                     socket.on(message.allAnswers, this.setAnswers);
 192                     initializeStage2(s.questions, s.paper);
 193                 },
 194             });
 195         },
 196
 197
 198         // stage 2
 199         runGlobalTimer: function() {
 200             if (assessment.time <= 0)
 201                 return;
 202             let self = this;
 203             setInterval( function() {
 204                 self.remainingTime--;
 205                 if (self.remainingTime <= 0)
 206                 {
 207                     if (self.stage == 2)
 208                         self.endAssessment();
 209                     clearInterval(this);
 210                 }
 211             }, 1000);
 212         },
 213         runQuestionTimer: function(idx) {
 214             if (assessment.questions[idx].time <= 0)
 215                 return;
 216             let self = this; //TODO: question remaining time
 217             setInterval( function() {
 218                 self.remainingTime--;
 219                 if (self.remainingTime <= 0)
 220                 {
 221                     if (self.stage == 2)
 222                         self.endAssessment();
 223                     clearInterval(this);
 224                 }
 225             }, 1000);
 226         },
 227
 228 //TODO: get question after sending answer
 229
 230         // stage 2
 231         sendOneAnswer: function() {
 232             const realIndex = this.answers.indices[this.answers.index];
 233             let gotoNext = () => {
 234                 if (this.answers.index == assessment.questions.length - 1)
 235                     this.endAssessment();
 236                 else
 237                     this.answers.index++;
 238                 this.$children[0].$forceUpdate(); //TODO: bad HACK, and shouldn't be required...
 239             };
 240             if (assessment.mode == "open")
 241                 return gotoNext(); //only local
 242             let answerData = {
 243                 aid: assessment._id,
 244                 answer: JSON.stringify({
 245                     index: realIndex.toString(),
 246                     input: this.answers.inputs[realIndex]
 247                         .map( (tf,i) => { return {val:tf,idx:i}; } )
 248                         .filter( item => { return item.val; })
 249                         .map( item => { return item.idx; })
 250                 }),
 251                 number: this.student.number,
 252                 password: this.student.password,
 253             };
 254             $.ajax("/send/answer", {
 255                 method: "GET",
 256                 data: answerData,
 257                 dataType: "json",
 258                 success: ret => {
 259                     if (!!ret.errmsg)
 260                         return this.showWarning(ret.errmsg);
 261                     gotoNext();
 262                     socket.emit(message.newAnswer, answerData);
 263                 },
 264             });
 265         },
 266         // TODO: I don't like that + sending should not be definitive in exam mode with display = all
 267         sendAnswer: function() {
 268             if (assessment.display == "one")
 269                 this.sendOneAnswer();
 270             else
 271                 assessment.questions.forEach(this.sendOneAnswer);
 272         },
 273         // stage 2 --> 3 (or 4)
 274         // from a message by statements component, or time over
 275         endAssessment: function() {
 276             // Set endTime, destroy password
 277             $("#leftButton, #rightButton").show();
 278             if (assessment.mode == "open")
 279             {
 280                 this.stage = 4;
 281                 this.answers.showSolution = true;
 282                 this.answers.displayAll = true;
 283                 return;
 284             }
 285             $.ajax("/end/assessment", {
 286                 method: "GET",
 287                 data: {
 288                     aid: assessment._id,
 289                     number: this.student.number,
 290                     password: this.student.password,
 291                 },
 292                 dataType: "json",
 293                 success: ret => {
 294                     if (!!ret.errmsg)
 295                         return this.showWarning(ret.errmsg);
 296                     this.stage = 3;
 297                     delete this.student["password"]; //unable to send new answers now
 298                 },
 299             });
 300         },
 301         // stage 3 --> 4 (on socket message "feedback")
 302         setAnswers: function(m) {
 303             const answers = JSON.parse(m.answers);
 304             for (let i=0; i<answers.length; i++)
 305                 assessment.questions[i].answer = answers[i];
 306             this.answers.showSolution = true;
 307             this.answers.displayAll = true;
 308             this.stage = 4;
 309             socket.disconnect();
 310             socket = null;
 311         },
 312     },
 313 });