word/quiz.js

   1 Array.prototype.shuffle = function () {
   2         for (let i = this.length - 1; i > 0; i--) {
   3                 const j = Math.floor(Math.random() * (i + 1)); // random index 0..i
   4                 [this[i], this[j]] = [this[j], this[i]]; // swap elements
   5         }
   6         return this;
   7 };
   8
   9 Set.prototype.filter = function (f) {
  10         return new Set([...this].filter(f));
  11 };
  12
  13 class WordQuiz {
  14         dataselect(json) {
  15                 this.data = this.datafilter(json);
  16                 let rows = Object.values(this.data);
  17                 rows = rows.filter(row => !row[3].length); // remove referenced categories
  18                 return rows.shuffle();
  19         }
  20
  21         datafilter(json) {
  22                 // find viable rows from json data
  23                 let ids = new Set(Object.keys(json));
  24                 const selection = {...json}; // clone
  25
  26                 for (let cat of selection[''][3]) {
  27                         if (selection[cat])
  28                         selection[cat][1] = 0; // keep root categories
  29                 }
  30
  31                 if (this.preset.cat !== undefined) {
  32                         ids.clear();
  33                         let children = this.preset.cat;
  34                         for (let loop = 0; children.length && loop < 20; loop++) {
  35                                 for (let child of children) ids.add(child.toString());
  36                                 children = children.map(cat => json[cat][3]).filter(is => is).flat()
  37                         }
  38                 }
  39                 if (this.preset.images) {
  40                         ids = ids.filter(id => json[id][2]);
  41                 }
  42                 if (this.preset.level !== undefined) {
  43                         ids = ids.filter(id => json[id][1] <= this.preset.level);
  44                 }
  45
  46                 // keep only wanted ids
  47                 for (let id in selection) {
  48                         if (id && !ids.has(id)) {
  49                                 delete selection[id];
  50                         }
  51                 }
  52
  53                 // retain orphaned references in grandparent categories
  54                 for (let id in selection) {
  55                         selection[id][3] = function subresolve(subs) {
  56                                 //console.log(subs);
  57                                 return (subs || []).flatMap(sub =>
  58                                         sub in selection ? [sub] : json[sub] ? subresolve(json[sub][3]) : []
  59                                 );
  60                         }(selection[id][3]);
  61                 }
  62                 return selection;
  63         }
  64
  65         configure(params = window.location.hash.split('#')) {
  66                 const opts = new Map(params.map(arg => arg.split(/[:=](.*)/)));
  67                 for (let [query, val] of opts) {
  68                         if (query.match(/^\d+$/)) {
  69                                 this.preset.cat = [parseInt(query)];
  70                         }
  71                         else if (query === 'level') {
  72                                 this.preset.level = parseInt(val);
  73                         }
  74                         else {
  75                                 this.preset[query] = val;
  76                         }
  77                 }
  78                 this.preset.dataurl = `/data/wordlist.${this.preset.lang}.json`
  79         }
  80
  81         setup() {
  82                 this.form = document.getElementById('quiz');
  83         }
  84
  85         load() {
  86                 this.configure();
  87                 fetch(this.preset.dataurl).then(res => res.json()).then(json => {
  88                         this.words = this.dataselect(json)
  89                         this.setup();
  90                 });
  91         }
  92
  93         log(...args) {
  94                 this.history.push([new Date().toISOString(), ...args]);
  95         }
  96
  97         stop(...args) {
  98                 this.log(...args);
  99                 window.onbeforeunload = null;
 100                 fetch('/word/report', {method: 'POST', body: JSON.stringify(this.history)});
 101         }
 102
 103         constructor() {
 104                 this.preset = {images: true, lang: 'en'};
 105                 this.load();
 106                 this.history = [];
 107                 window.onbeforeunload = e => {
 108                         this.stop('abort');
 109                 };
 110                 window.onhashchange = e => {
 111                         this.load();
 112                 };
 113         }
 114 }