From fc37c5e4c2bb4daa7a61714555a68b43930fc211 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Bart=C5=82omiej=20Dach?= <dach.bartlomiej@gmail.com>
Date: Tue, 16 Jan 2024 20:18:32 +0100
Subject: [PATCH] Fix taiko maps containing only drum rolls / swells not being
 passable without mods

Closes https://github.com/ppy/osu/issues/26370.

As was noted in the issue thread stable does not attempt to account for
such maps, and the maps are impassable in stable without No Fail.
Nevertheless that seems like a pretty anti-player behaviour and I
honestly believe that it is fine to change this in lazer.
---
 .../Scoring/TaikoHealthProcessor.cs           | 28 +++++++++++++++++++
 1 file changed, 28 insertions(+)

diff --git a/osu.Game.Rulesets.Taiko/Scoring/TaikoHealthProcessor.cs b/osu.Game.Rulesets.Taiko/Scoring/TaikoHealthProcessor.cs
index d75906f3aa..dfca4ac8c7 100644
--- a/osu.Game.Rulesets.Taiko/Scoring/TaikoHealthProcessor.cs
+++ b/osu.Game.Rulesets.Taiko/Scoring/TaikoHealthProcessor.cs
@@ -31,11 +31,39 @@ public partial class TaikoHealthProcessor : AccumulatingHealthProcessor
         /// </summary>
         private double hpMissMultiplier;
 
+        /// <summary>
+        /// Sum of all achievable health increases throughout the map.
+        /// Used to determine if there are any objects that give health.
+        /// If there are none, health will be forcibly pulled up to 1 to avoid cases of impassable maps.
+        /// </summary>
+        private double sumOfMaxHealthIncreases;
+
         public TaikoHealthProcessor()
             : base(0.5)
         {
         }
 
+        protected override void ApplyResultInternal(JudgementResult result)
+        {
+            base.ApplyResultInternal(result);
+            sumOfMaxHealthIncreases += result.Judgement.MaxHealthIncrease;
+        }
+
+        protected override void RevertResultInternal(JudgementResult result)
+        {
+            base.RevertResultInternal(result);
+            sumOfMaxHealthIncreases -= result.Judgement.MaxHealthIncrease;
+        }
+
+        protected override void Reset(bool storeResults)
+        {
+            base.Reset(storeResults);
+
+            if (storeResults && sumOfMaxHealthIncreases == 0)
+                Health.Value = 1;
+            sumOfMaxHealthIncreases = 0;
+        }
+
         public override void ApplyBeatmap(IBeatmap beatmap)
         {
             base.ApplyBeatmap(beatmap);