From 785b359d37d2ccfb844e193667a48f2296bf9c4e Mon Sep 17 00:00:00 2001
From: Manuel Thalmann <m@nuth.ch>
Date: Tue, 8 Nov 2022 22:18:33 +0100
Subject: [PATCH] Add code for determining and drawing a route

---
 .../ch/nuth/zhaw/exbox/LabyrinthServer.java   | 37 +++++++++++++++++--
 1 file changed, 33 insertions(+), 4 deletions(-)

diff --git a/app/src/main/java/ch/nuth/zhaw/exbox/LabyrinthServer.java b/app/src/main/java/ch/nuth/zhaw/exbox/LabyrinthServer.java
index a717b3a..bf92073 100644
--- a/app/src/main/java/ch/nuth/zhaw/exbox/LabyrinthServer.java
+++ b/app/src/main/java/ch/nuth/zhaw/exbox/LabyrinthServer.java
@@ -51,14 +51,43 @@ public class LabyrinthServer implements CommandExecutor {
         }
     }
 
-    private boolean search(DijkstraNode current, DijkstraNode ziel) {
-        // TODO implement 8.4
-        return false;
+    private boolean search(DijkstraNode current, DijkstraNode destination) {
+        current.setMark(true);
+
+        if (current == destination) {
+            return true;
+        } else {
+            for (Edge edge : current.getEdges()) {
+                if (edge.getDest() instanceof DijkstraNode node &&
+                        !node.getMark()) {
+                    node.setPrev(current);
+
+                    if (search(node, destination)) {
+                        return true;
+                    } else {
+                        node.setPrev(null);
+                    }
+                }
+            }
+
+            return false;
+        }
     }
 
     // search and draw result
-    public void drawRoute(Graph<DijkstraNode, Edge> graph, String startNode, String zielNode) {
+    public void drawRoute(Graph<DijkstraNode, Edge> graph, String startNode, String destinationNode) {
         // TODO implement 8.4
+        ServerGraphics graphics = getGraphics();
+        DijkstraNode currentNode = graph.findNode(destinationNode);
+        graphics.setColor(Color.RED);
+
+        if (search(graph.findNode(startNode), currentNode)) {
+            while (currentNode.getPrev() != null) {
+                DijkstraNode previousNode = currentNode.getPrev();
+                graphics.drawPath(previousNode.getName(), currentNode.getName(), true);
+                currentNode = previousNode;
+            }
+        }
     }
 
     public String execute(String s) {