Added logs to track the issues, started doing changes based on the school api project

Examples/Nodify.Calculator/Execution/Handlers/NodeHandlers.cs

@@ -198,7 +198,7 @@ namespace Nodify.Calculator.Execution.Handlers
 
                 var bodyNode = loopBodyConnection?.Input?.Operation;
                 if (bodyNode != null)
-                    ctx.Executor.TraverseChainPublic(bodyNode, "end", ctx.Connections, new HashSet<string>(), true);
+                    ctx.Executor.ExecuteLinearChain(bodyNode, ctx.Connections);
             }
             ctx.Log($"[FOREACH] Loop completed. {array.Count} iterations executed.");
         }

Examples/Nodify.Calculator/Execution/Resolvers/NodeValueResolvers.cs

@@ -56,13 +56,35 @@ namespace Nodify.Calculator.Execution.Resolvers
         {
             // Split's model input is the Square-shaped connector
             var modelInput = node.Input.FirstOrDefault(i => i.Shape == ConnectorShape.Square);
-            if (modelInput == null) return null;
+            if (modelInput == null)
+            {
+                ctx.Log("[SPLIT] No Square input connector found.", logType.Warning);
+                return null;
+            }
 
             var modelJson = ctx.Read(modelInput);
+            ctx.Log($"[SPLIT] Input JSON: {(modelJson?.Length > 120 ? modelJson.Substring(0, 120) + "..." : modelJson ?? "(null)")}");
             if (string.IsNullOrWhiteSpace(modelJson)) return null;
 
             var propName = ResolverUtils.NormalizeConnectorName(outputConnector.Title);
-            return ResolverUtils.ExtractJsonProperty(modelJson, propName);
+            ctx.Log($"[SPLIT] Looking for property: \"{propName}\"");
+
+            // Try direct property extraction first
+            var result = ResolverUtils.ExtractJsonProperty(modelJson, propName);
+
+            // If not found at top level, try unwrapping a "data" envelope
+            if (result == null)
+            {
+                var dataInner = ResolverUtils.ExtractJsonProperty(modelJson, "data");
+                if (!string.IsNullOrWhiteSpace(dataInner))
+                {
+                    ctx.Log("[SPLIT] Property not found at top level, unwrapping \"data\" envelope...");
+                    result = ResolverUtils.ExtractJsonProperty(dataInner, propName);
+                }
+            }
+
+            ctx.Log($"[SPLIT] Resolved \"{propName}\" = {result ?? "(null)"}");
+            return result;
         }
     }
 

Examples/Nodify.Calculator/Executor.cs

@@ -208,24 +208,51 @@ namespace Nodify.Calculator
             var sourceOp = sourceConnector?.Operation;
             var srcNodeId = sourceOp?.NodeId;
 
+            OnLogMe?.Invoke($"[RESOLVE] Reading input \"{input.Title}\" ? source node \"{sourceOp?.Title}\" (connector \"{sourceConnector?.Title}\")");
+
             // 1. Flow-executed nodes record their result in outputs[nodeId].
             if (srcNodeId != null && outputs.TryGetValue(srcNodeId, out var producedVal))
+            {
+                OnLogMe?.Invoke($"[RESOLVE] Found in outputs[{sourceOp?.Title}]: {(producedVal?.Length > 80 ? producedVal.Substring(0, 80) + "..." : producedVal)}");
                 return producedVal;
+            }
 
             // 2. Generic dispatch for non-flow (sideband) nodes.
             if (sourceOp != null && sourceConnector != null)
             {
+                OnLogMe?.Invoke($"[RESOLVE] No cached output for \"{sourceOp.Title}\", trying value resolvers...");
                 var resCtx = new ValueResolutionContext(this, connections);
                 foreach (var resolver in _valueResolvers)
                 {
                     if (!resolver.CanResolve(sourceOp, sourceConnector)) continue;
+                    OnLogMe?.Invoke($"[RESOLVE] Matched resolver: {resolver.GetType().Name}");
                     var resolved = resolver.Resolve(sourceOp, sourceConnector, resCtx);
                     if (!string.IsNullOrEmpty(resolved))
+                    {
+                        OnLogMe?.Invoke($"[RESOLVE] Resolver returned: {(resolved.Length > 80 ? resolved.Substring(0, 80) + "..." : resolved)}");
                         return resolved;
                     }
+                    OnLogMe?.Invoke($"[RESOLVE] Resolver returned null/empty, trying next...", logType.Warning);
+                }
+                OnLogMe?.Invoke($"[RESOLVE] No resolver produced a value for \"{sourceOp.Title}\"", logType.Warning);
+
+                // 2b. Fallback: if no resolver handled this non-flow node, try to recursively
+                // resolve its first data input and pass the value through (generic passthrough).
+                var fallbackInput = sourceOp.Input.FirstOrDefault(i => i.Shape != ConnectorShape.Triangle);
+                if (fallbackInput != null)
+                {
+                    OnLogMe?.Invoke($"[RESOLVE] Attempting generic passthrough for \"{sourceOp.Title}\"...");
+                    var passthrough = TryReadInputValue(fallbackInput, connections);
+                    if (!string.IsNullOrEmpty(passthrough))
+                    {
+                        OnLogMe?.Invoke($"[RESOLVE] Passthrough returned: {(passthrough.Length > 80 ? passthrough.Substring(0, 80) + "..." : passthrough)}");
+                        return passthrough;
+                    }
+                }
             }
 
             // 3/4. Fall back to connector/default values.
+            OnLogMe?.Invoke($"[RESOLVE] Falling back to connector Value: {sourceConnector?.Value}", logType.Warning);
             if (sourceConnector?.Value != null)
                 return sourceConnector.Value.ToString();
             return input.Value.ToString();
@@ -483,6 +510,39 @@ namespace Nodify.Calculator
                                            HashSet<string> visited, bool isExecute)
             => TraverseChain(node, endNodeTitle, connections, visited, isExecute);
 
+        /// <summary>
+        /// Executes a linear chain of nodes without requiring an "End" node.
+        /// Used for loop bodies where the chain simply terminates at the last node.
+        /// </summary>
+        internal void ExecuteLinearChain(OperationViewModel startNode,
+                                         ICollection<ConnectionViewModel> connections)
+        {
+            var visited = new HashSet<string>();
+            var current = startNode;
+            while (current != null)
+            {
+                if (visited.Contains(current.NodeId))
+                    break;
+                visited.Add(current.NodeId);
+
+                SetNodeState(current, ExecutionState.Running);
+                System.Threading.Thread.Sleep(AnimationDelayMs / 2);
+                StartExecution(current, connections);
+                SetNodeState(current, ExecutionState.Completed);
+
+                // Find next node via outgoing Triangle connection
+                var outConn = connections.FirstOrDefault(c => c.Output?.Operation == current && c.Output.Shape == ConnectorShape.Triangle);
+                if (outConn?.Input?.Operation == null)
+                    break;
+
+                SetConnectionActive(outConn, true);
+                System.Threading.Thread.Sleep(AnimationDelayMs);
+                SetConnectionActive(outConn, false);
+
+                current = outConn.Input.Operation;
+            }
+        }
+
         internal void AddNewModelPublic(OperationInfoViewModel model)
             => editorViewModel.Calculator.OperationsMenu.AddNewModel(model);