Weight news so that recent items are less likely to appear

gorge.js

@@ -48,6 +48,8 @@ let newsRemoveTimer;
 
 const newsDelay = 8000;
 
+const newsWeightFactors = [];
+
 let buttonClicked = false;
 
 const state = {
@@ -531,6 +533,7 @@ function setup() {
   // prepare dynamic stuff
 
   initializeData();
+  initializeNews();
   createButtons();
   createDisplays();
   registerListeners();
@@ -541,6 +544,12 @@ function setup() {
   updateAll();
 }
 
+function initializeNews() {
+  news.forEach(entry => {
+    newsWeightFactors.push(0);
+  });
+}
+
 const cache = {};
 
 function initializeCaches() {
@@ -1116,16 +1125,28 @@ function clickPopup(text, type, location) {
 
 function doNews() {
   let options = [];
+  let weights = [];
+  let indices = [];
+  let index = 0;
   news.forEach(entry => {
-    if (entry.condition(state)) {
+    if (entry.condition(state) && newsWeightFactors[index] != 1) {
       options = options.concat(entry.lines);
+      weights.push(1 - newsWeightFactors[index])
+      indices.push(index);
     }
+    index += 1;
   });
 
-  const choice = Math.floor(Math.random() * options.length);
-
+  const choice = weightedSelect(weights);
+  
   showNews(options[choice](state));
 
+  for (let i = 0; i < newsWeightFactors.length; i++) {
+    newsWeightFactors[i] *= 0.9;
+  }
+
+  newsWeightFactors[indices[choice]] = 1;
+
   newsShowTimer = setTimeout(() => {
     doNews();
   }, 8000);

util.js

@@ -53,3 +53,16 @@ function capitalize(string) {
 function weekday() {
   return ["Sunday", "Monday", "Tuesday", "Wednesday", "Thursday", "Friday", "Saturday"][(new Date()).getDay()];
 }
+
+function weightedSelect(weights) {
+  const total = weights.reduce((x,y) => x+y, 0);
+  const rand = Math.random() * total;
+  let counter = weights[0];
+  let index = 0;
+  while (counter < rand) {
+    index += 1;
+    counter += weights[index];
+  }
+
+  return index;
+}