add libpoketube core utils

src/libpoketube/ptutils/libpt-coreutils.js

@@ -0,0 +1,62 @@
+/*
+
+    PokeTube is a Free/Libre youtube front-end !
+    
+    Copyright (C) 2021-2022 POKETUBE
+ 
+    This file is Licensed under LGPL-3.0-or-later. Poketube itself is GPL, Only this file is LGPL.
+    
+    see a copy here:https://www.gnu.org/licenses/lgpl-3.0.txt
+    
+    please dont remove this comment while sharing this code 
+    
+  */
+
+function IsJsonString(str) {
+  try {
+    JSON.parse(str);
+  } catch (e) {
+    return false;
+  }
+  return true;
+}
+
+function convert(value) {
+  return new Intl.NumberFormat("en-GB", {
+    notation: "compact",
+  }).format(value);
+}
+
+function getFirstLine(text) {
+  var index = text.indexOf("<br> ");
+  if (index === -1) index = undefined;
+  return text.substring(0, index);
+}
+
+function capitalizeFirstLetter(string) {
+  return string.charAt(0).toUpperCase() + string.slice(1);
+}
+
+function turntomins(time) {
+  var minutes = Math.floor(time / 60);
+
+  var seconds = time - minutes * 60;
+
+  function str_pad_left(string, pad, length) {
+    return (new Array(length + 1).join(pad) + string).slice(-length);
+  }
+
+  var finalTime =
+    str_pad_left(minutes, "0", 2) + ":" + str_pad_left(seconds, "0", 2);
+
+  return finalTime;
+};
+
+
+module.exports = {
+IsJsonString,
+convert,
+getFirstLine,
+capitalizeFirstLetter,
+turntomins
+};