From fdb9aa8e84bc4e8e1391a32f0d50ef28be9db87d Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Luk=C3=A1=C5=A1=20Kucharczyk?= <lukas@kucharczyk.xyz>
Date: Thu, 5 Jan 2023 11:14:00 +0100
Subject: [PATCH] Add format_duration to common.util.time

---
 CHANGELOG.md                |  1 +
 src/web/common/util/time.py | 39 ++++++++++++++++++++++++++++++++++++-
 2 files changed, 39 insertions(+), 1 deletion(-)

diff --git a/CHANGELOG.md b/CHANGELOG.md
index 55d55ff..2a976fd 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,4 +1,5 @@
 ## Unreleased
+* Add format_duration to common.util.time
 * Allow deleting sessions
 * Redirect after adding game/platform/purchase/session
 * Fix display of duration_manual
diff --git a/src/web/common/util/time.py b/src/web/common/util/time.py
index 57c8885..13ee8a1 100644
--- a/src/web/common/util/time.py
+++ b/src/web/common/util/time.py
@@ -1,7 +1,44 @@
-from datetime import datetime
+from datetime import datetime, timedelta
 from django.conf import settings
 from zoneinfo import ZoneInfo
+import re
 
 
 def now():
     return datetime.now(ZoneInfo(settings.TIME_ZONE))
+
+
+def format_duration(
+    duration: timedelta, format_string: str = "%H hours %m minutes"
+) -> str:
+    """
+    Format timedelta into the specified format_string.
+    If duration is less than 60 seconds, skips formatting, returns "less than a minute".
+    If duration is 0, skips formatting, returns 0.
+    Valid format variables:
+    - %H hours
+    - %m minutes
+    - %s seconds
+    """
+    seconds_in_hours = 3600
+    seconds_in_minute = 60
+    hours: int
+    minutes: int
+    seconds: int
+    seconds_total: int
+    remainder: int
+    seconds_total = duration.total_seconds()
+    if seconds_total == 0:
+        return 0
+    else:
+        hours = int(seconds_total // seconds_in_hours)
+        remainder = int(seconds_total % seconds_in_hours)
+        minutes = int(remainder // seconds_in_minute)
+        if hours == 0 and minutes == 0:
+            return "less than a minute"
+        seconds = int(minutes % seconds_in_minute)
+        literals = {"%H": str(hours), "%m": str(minutes), "%s": str(seconds)}
+        formatted_string = format_string
+        for pattern, replacement in literals.items():
+            formatted_string = re.sub(pattern, replacement, formatted_string)
+        return formatted_string