Improve execution logic / Fix group node execution (#4422)

src/utils/executableGroupNodeChildDTO.ts

@@ -0,0 +1,53 @@
+import {
+  type ExecutableLGraphNode,
+  ExecutableNodeDTO,
+  type ExecutionId,
+  type LGraphNode,
+  type NodeId,
+  type SubgraphNode
+} from '@comfyorg/litegraph'
+
+import type { GroupNodeHandler } from '@/extensions/core/groupNode'
+
+export class ExecutableGroupNodeChildDTO extends ExecutableNodeDTO {
+  groupNodeHandler?: GroupNodeHandler
+
+  constructor(
+    /** The actual node that this DTO wraps. */
+    node: LGraphNode | SubgraphNode,
+    /** A list of subgraph instance node IDs from the root graph to the containing instance. @see {@link id} */
+    subgraphNodePath: readonly NodeId[],
+    /** A flattened map of all DTOs in this node network. Subgraph instances have been expanded into their inner nodes. */
+    nodesByExecutionId: Map<ExecutionId, ExecutableLGraphNode>,
+    /** The actual subgraph instance that contains this node, otherise undefined. */
+    subgraphNode?: SubgraphNode | undefined,
+    groupNodeHandler?: GroupNodeHandler
+  ) {
+    super(node, subgraphNodePath, nodesByExecutionId, subgraphNode)
+    this.groupNodeHandler = groupNodeHandler
+  }
+
+  override resolveInput(slot: number) {
+    const inputNode = this.node.getInputNode(slot)
+    if (!inputNode) return
+
+    const link = this.node.getInputLink(slot)
+    if (!link) throw new Error('Failed to get input link')
+
+    const id = String(inputNode.id).split(':').at(-1)
+    if (id === undefined) throw new Error('Invalid input node id')
+
+    const inputNodeDto = this.nodesByExecutionId?.get(id)
+    if (!inputNodeDto) {
+      throw new Error(
+        `Failed to get input node ${id} for group node child ${this.id} with slot ${slot}`
+      )
+    }
+
+    return {
+      node: inputNodeDto,
+      origin_id: inputNode.id,
+      origin_slot: link.origin_slot
+    }
+  }
+}