From c590c168f4b41d8e37e09d064288d5d0b77ac28f Mon Sep 17 00:00:00 2001
From: Marc Emmanuel <marc.emmanuel@tado.com>
Date: Fri, 23 Jan 2026 13:47:35 +0100
Subject: [PATCH] fix: update colorUtils and probabilityUtils to use seeded
 randomness (#1280)

---
 src/utils/colorUtils.ts       | 5 ++++-
 src/utils/probabilityUtils.ts | 4 +++-
 2 files changed, 7 insertions(+), 2 deletions(-)

diff --git a/src/utils/colorUtils.ts b/src/utils/colorUtils.ts
index 047d6eae..e64636fc 100644
--- a/src/utils/colorUtils.ts
+++ b/src/utils/colorUtils.ts
@@ -1,4 +1,4 @@
-import { color, interpolate, interpolateRainbow, range, RGBColor, scaleSequential, shuffle } from "d3";
+import { color, interpolate, interpolateRainbow, range, RGBColor, scaleSequential, shuffler } from "d3";
 
 /**
  * Convert RGB or RGBA color to HEX
@@ -35,11 +35,14 @@ export const C_12 = [
 
 /** 
  * Get an array of distinct colors
+ * Uses shuffler with current Math.random to ensure seeded randomness works
  * @param {number} count - The count of colors to generate
  * @returns {string[]} - The array of HEX color strings
 */
 export const getColors = (count: number): string[] => {
   const scaleRainbow = scaleSequential(interpolateRainbow);
+  // Use shuffler() to create a shuffle function that uses the current Math.random
+  const shuffle = shuffler(() => Math.random());
   const colors = shuffle(
     range(count).map(i => (i < 12 ? C_12[i] : color(scaleRainbow((i - 12) / (count - 12)))?.formatHex()))
   );
diff --git a/src/utils/probabilityUtils.ts b/src/utils/probabilityUtils.ts
index 4f6fd66a..a526c981 100644
--- a/src/utils/probabilityUtils.ts
+++ b/src/utils/probabilityUtils.ts
@@ -38,6 +38,7 @@ export const each = (n: number) => {
 
 /**
  * Random Gaussian number generator
+ * Uses randomNormal.source(Math.random) to ensure it uses the current PRNG
  * @param {number} expected - expected value
  * @param {number} deviation - standard deviation
  * @param {number} min - minimum value
@@ -46,7 +47,8 @@ export const each = (n: number) => {
  * @return {number} random number
  */
 export const gauss = (expected = 100, deviation = 30, min = 0, max = 300, round = 0) => {
-  return rn(minmax(randomNormal(expected, deviation)(), min, max), round);
+  // Use .source() to get a version that uses the current Math.random (which may be seeded)
+  return rn(minmax(randomNormal.source(() => Math.random())(expected, deviation)(), min, max), round);
 }
 
 /**