From 993482f8c042c1c495828ed68a22fd6e2e93e65e Mon Sep 17 00:00:00 2001
From: "p.vanderwilt" <p.van.der.wilt@brabantsedelta.nl>
Date: Mon, 29 Sep 2025 16:58:46 +0200
Subject: [PATCH] Deal with mulitple parents and set downstreamReactor for
 improved boundary conditions

---
 src/specificClass.js | 16 +++++++++++-----
 1 file changed, 11 insertions(+), 5 deletions(-)

diff --git a/src/specificClass.js b/src/specificClass.js
index 4d329b6..83829d8 100644
--- a/src/specificClass.js
+++ b/src/specificClass.js
@@ -27,7 +27,9 @@ class Reactor {
     this.measurements = new MeasurementContainer();
     this.upstreamReactor = null;
     this.childRegistrationUtils = new childRegistrationUtils(this); // Child registration utility
-    this.parent = null; // Gets assigned via child registration
+    this.parent = []; // Gets assigned via child registration
+
+    this.upstreamReactor = null;
 
     this.asm = new ASM3();
 
@@ -114,6 +116,10 @@ class Reactor {
     }
   }
 
+  setDownstreamReactor() {
+    this.downstreamReactor = this.parent.find((x) => x.config.functionality.softwareType == "reactor");
+  }
+
   _connectMeasurement(measurementChild) {
     if (!measurementChild) {
       this.logger.warn("Invalid measurement provided.");
@@ -152,6 +158,7 @@ class Reactor {
     }
 
     this.upstreamReactor = reactorChild;
+    reactorChild.setDownstreamReactor();
 
     reactorChild.emitter.on("stateChange", (data) => {
       this.logger.debug(`State change of upstream reactor detected.`);
@@ -323,7 +330,7 @@ class Reactor_PFR extends Reactor {
   _updateMeasurement(measurementType, value, position, context) {
     switch(measurementType) {
       case "quantity (oxygen)":
-        grid_pos = Math.round(position / this.config.length * this.n_x);
+        let grid_pos = Math.round(position / this.config.length * this.n_x);
         this.state[grid_pos][S_O_INDEX] = value; // naive approach for reconciling measurements and simulation
         break;
       default:
@@ -350,9 +357,8 @@ class Reactor_PFR extends Reactor {
       }
     }
 
-    const downstreamReactor = this.parent;
-    if (downstreamReactor) {
-      state[this.n_x-1] = downstreamReactor.state[0];
+    if (this.downstreamReactor) {
+      state[this.n_x-1] = this.downstreamReactor.state[0];
     } else {
       // Neumann BC (no flux)
       state[this.n_x-1] = state[this.n_x-2];