From f274513bb58108697f846e9367cad63bca6b9fe5 Mon Sep 17 00:00:00 2001
From: Nikita Vilunov <nikita@vilunov.me>
Date: Mon, 28 Oct 2024 22:40:39 +0100
Subject: [PATCH] improve track selection entropy

---
 MuzikaGromche/Plugin.cs | 16 ++++++++++++++--
 1 file changed, 14 insertions(+), 2 deletions(-)

diff --git a/MuzikaGromche/Plugin.cs b/MuzikaGromche/Plugin.cs
index 254b847..b6de3df 100644
--- a/MuzikaGromche/Plugin.cs
+++ b/MuzikaGromche/Plugin.cs
@@ -1,6 +1,8 @@
-using System.Collections;
+using System;
+using System.Collections;
 using System.Collections.Generic;
 using System.Linq;
+using System.Security.Cryptography;
 using BepInEx;
 using HarmonyLib;
 using UnityEngine;
@@ -129,7 +131,17 @@ namespace MuzikaGromche
 	        {
 		        //  ...and start modded music
 		        var seed = RoundManager.Instance.dungeonGenerator.Generator.ChosenSeed;
-		        var trackId = seed % Plugin.Tracks.Length;
+		        var sha = SHA256.Create();
+		        var hash = sha.ComputeHash(BitConverter.GetBytes(seed));
+		        var trackId = 0;
+		        foreach (var t in hash)
+		        {
+			        // modulus division on byte array
+			        trackId *= 256 % Plugin.Tracks.Length;
+			        trackId %= Plugin.Tracks.Length;
+			        trackId += t % Plugin.Tracks.Length;
+			        trackId %= Plugin.Tracks.Length;
+		        }
 		        Debug.Log($"Seed is {seed}, chosen track is {trackId} out of {Plugin.Tracks.Length} tracks");
 		        Plugin.CurrentTrack = Plugin.Tracks[trackId];
 		        __instance.popUpTimer = Plugin.CurrentTrack.WindUpTimer;