refactor: [torrust#297] new error checks and refactoring

Date converter helper function now throws errors if the timestamp passed as argument is not an integer
and if the Date() constructor returns an invalid date.

Author: mario-nt

components/torrent/TorrentCreationDateTab.vue

@@ -14,8 +14,7 @@
     <template v-if="!collapsed">
       <div class="flex flex-col w-full h-full p-6 grow bg-base-100 rounded-2xl">
         <template v-if="torrent.creation_date">
-          <!--<Markdown :source="torrent.name" />-->
-          {{ creationDateUTC }}
+          {{ unixTimeToHumanReadableUTC(torrent.creation_date) }}
         </template>
         <template v-else>
           <span class="italic text-neutral-content">No creation date provided.</span>
@@ -42,8 +41,6 @@ const props = defineProps({
   }
 });
 
-const creationDateUTC = unixTimeToHumanReadableUTC(props.torrent.creation_date);
-
 </script>
 
 <style scoped>

src/helpers/DateConverter.ts

@@ -1,14 +1,34 @@
 type UnixTime = number;
 
-function isValidDate (date: Date) {
-  return date instanceof Date && !isNaN(date.valueOf());
-}
+class InvalidDateError extends Error {}
 
 // Takes the date in seconds from Epoch time and converts it to human readable format.
 
-export function unixTimeToHumanReadableUTC (seconds: UnixTime) {
+export function unixTimeToHumanReadableUTC (creationDate: UnixTime) {
+  try {
+    return dateFromSeconds(creationDate);
+  } catch (error) {
+    return ("Invalid date");
+  }
+}
+
+function dateFromSeconds (seconds: number) {
+  if (!validateTimestamp(seconds))
+  { throw new TypeError("Torrent creation date is not an integer"); }
+
   const milliseconds = seconds * 1000;
   const convertedDate = new Date(milliseconds);
 
-  return isValidDate(convertedDate) ? convertedDate.toDateString() : "Invalid date";
+  if (!validateDate(convertedDate))
+  { throw new InvalidDateError("Date is not valid"); }
+
+  return convertedDate.toDateString();
+}
+
+function validateDate (date: Date) {
+  return date instanceof Date && !isNaN(date.valueOf());
+}
+
+function validateTimestamp (timestamp: UnixTime) {
+  return Number.isInteger(timestamp);
 }