✨ Create convertToLocalISODate function

code/frontend/src/utils/convertToLocalISODate.js

@@ -0,0 +1,30 @@
+// Wow, JS, davvero?
+// Davvero tutte le date.toISOString() sono considerate UTC?
+// Wow.
+
+/**
+ * Convert a {@link Date} object to a timezone aware ISO String, using the user's local timezone.
+ *
+ * @param date
+ * @returns {string}
+ */
+export default function convertToLocalISODate(date) {
+    if(date.toString() === "Invalid Date") {
+        throw new Error("Received an Invalid Date as parameter.")
+    }
+
+    // Create a timezone naive ISO string
+    const naive = date.toISOString()
+
+    // Find the local timezone
+    const tz = - new Date().getTimezoneOffset()
+
+    // Convert the timezone to hours
+    const tzHours = Math.abs(Math.floor(tz / 60)).toString().padStart(2, "0")
+
+    // Find the minutes
+    const tzMinutes = (tz % 60).toString().padStart(2, "0")
+
+    // Replace the naive part with the aware part
+    return naive.replace("Z", `${tz < 0 ? "-" : "+"}${tzHours}${tzMinutes}`)
+}