From a8b0ea1755a1a767ddbd33635d79fcb171569def Mon Sep 17 00:00:00 2001
From: Miguel Campos <amodestduck@gmail.com>
Date: Fri, 12 Jan 2024 21:41:06 -0800
Subject: [PATCH] add util methods for durations and percentages

---
 libs/util/numbers/src/lib/numbers.ts | 12 +++++++++++
 libs/util/time/src/lib/time.ts       | 32 ++++++++++++++++++++++++++++
 2 files changed, 44 insertions(+)

diff --git a/libs/util/numbers/src/lib/numbers.ts b/libs/util/numbers/src/lib/numbers.ts
index 9b7204080..be36c49ac 100644
--- a/libs/util/numbers/src/lib/numbers.ts
+++ b/libs/util/numbers/src/lib/numbers.ts
@@ -20,3 +20,15 @@ export function shorthandNumber(n: number): string {
   // else return n
   return `${n}`;
 }
+
+export function calculatePercentage(current?: number, max?: number) {
+  if (!current || !max) return 0;
+  if (current > max) return 0;
+  if (current < 0 || max < 0) return 0;
+
+  return Math.min(Math.round((current / max) * 100), 100);
+}
+
+export function toPercentage(current?: number, max?: number) {
+  return `${calculatePercentage(current, max)}%`;
+}
diff --git a/libs/util/time/src/lib/time.ts b/libs/util/time/src/lib/time.ts
index c73f5f397..57a6b91c9 100644
--- a/libs/util/time/src/lib/time.ts
+++ b/libs/util/time/src/lib/time.ts
@@ -149,3 +149,35 @@ export const formatAmericanDate = (stamp: string) => {
 export const waitFor = (wait: number): Promise<void> => {
   return new Promise((resolve) => setTimeout(resolve, wait));
 };
+
+/**
+ * @name timeUntil
+ * @definition used to calculate the amount of time until a specified date and time.
+ * @params {number} timestamp - the timestamp to calculate the amount of time until.
+ * @returns {number} the amount of time in milliseconds until the specified time.
+ */
+
+export const timeUntil = (timestamp: number): number => {
+  return timestamp - Date.now();
+};
+
+/**
+ * @name millisecondsToDuration
+ * @definition used to convert a number of milliseconds into a duration string.
+ * @params {number} milliseconds - the number of milliseconds to convert.
+ * @returns {string} the duration string.
+ * @example millisecondsToDuration(1000) // "00:00:01"
+ * @example millisecondsToDuration(1000 * 60) // "00:01:00"
+ * @example millisecondsToDuration(1000 * 60 * 60) // "01:00:00"
+ */
+export const millisecondsToDuration = (milliseconds: number): string => {
+  // count the number of hours, minutes, and seconds in the milliseconds
+  const hours = Math.floor(milliseconds / (1000 * 60 * 60));
+  const minutes = Math.floor(milliseconds / (1000 * 60)) % 60;
+  const seconds = Math.floor(milliseconds / 1000) % 60;
+
+  // print the hours, minutes, and seconds in the format HH:MM:SS
+  return `${hours.toString().padStart(2, '0')}:${minutes
+    .toString()
+    .padStart(2, '0')}:${seconds.toString().padStart(2, '0')}`;
+};