From 81a263b7d0ab02edce49ceb4ea2888c41ee556b6 Mon Sep 17 00:00:00 2001
From: Chomp <dev@dev.sp-tarkov.com>
Date: Mon, 30 Jun 2025 10:12:55 +0100
Subject: [PATCH] Fixed incorrect logic in how weekly reset date is picked,
 choose the most recent previous day, not the closest

---
 .../Extensions/DateTimeExtensions.cs          | 26 ++++++++++++++++++-
 .../Services/PostDbLoadService.cs             |  2 +-
 2 files changed, 26 insertions(+), 2 deletions(-)

diff --git a/Libraries/SPTarkov.Server.Core/Extensions/DateTimeExtensions.cs b/Libraries/SPTarkov.Server.Core/Extensions/DateTimeExtensions.cs
index 0b35c730..14e4af69 100644
--- a/Libraries/SPTarkov.Server.Core/Extensions/DateTimeExtensions.cs
+++ b/Libraries/SPTarkov.Server.Core/Extensions/DateTimeExtensions.cs
@@ -113,7 +113,7 @@
         /// <param name="dateTime">Date to get closest monday of</param>
         /// <param name="startDay">Starting day of week - Default = Monday</param>
         /// <returns>Monday as DateTime</returns>
-        public static DateTime GetStartOfWeek(
+        public static DateTime GetClosestDate(
             this DateTime dateTime,
             DayOfWeek startDay = DayOfWeek.Monday
         )
@@ -124,5 +124,29 @@
             // Subtract difference to get date of most recent Monday
             return dateTime.AddDays(-1 * diff).Date;
         }
+
+        /// <summary>
+        /// Get the most recent requested day from date
+        /// </summary>
+        /// <param name="dateTime">Date to start from</param>
+        /// <param name="desiredDay">Desired day to find</param>
+        /// <param name="inclusiveOfToday">Should today be included in check, default = true</param>
+        /// <returns>Datetime of desired day</returns>
+        public static DateTime GetMostRecentPreviousDay(
+            this DateTime dateTime,
+            DayOfWeek desiredDay,
+            bool inclusiveOfToday = true
+        )
+        {
+            // Go back 1 day if we don't count today (exclusive)
+            var closestDate = inclusiveOfToday ? dateTime : dateTime.AddDays(-1);
+
+            while (closestDate.DayOfWeek != desiredDay)
+            {
+                closestDate = closestDate.AddDays(-1);
+            }
+
+            return closestDate;
+        }
     }
 }
diff --git a/Libraries/SPTarkov.Server.Core/Services/PostDbLoadService.cs b/Libraries/SPTarkov.Server.Core/Services/PostDbLoadService.cs
index cdf359a6..e6d1a9c9 100644
--- a/Libraries/SPTarkov.Server.Core/Services/PostDbLoadService.cs
+++ b/Libraries/SPTarkov.Server.Core/Services/PostDbLoadService.cs
@@ -147,7 +147,7 @@ public class PostDbLoadService(
     protected WildSpawnType GetWeeklyBoss(List<WildSpawnType> bosses, DayOfWeek bossResetDay)
     {
         // Get closest monday to today
-        var startOfWeek = DateTime.Today.GetStartOfWeek(bossResetDay);
+        var startOfWeek = DateTime.Today.GetMostRecentPreviousDay(bossResetDay);
 
         // Create a consistent seed for the week using the year and the day of the year of above monday chosen
         // This results in seed being identical for the week