Merge pull request #154 from ilyabesk/replace_connection_improvements

Cheanges to allow ability to automatically create inputs if required.

src/litegraph.d.ts

@@ -952,6 +952,17 @@ export declare class LGraphNode {
         slotIndex: number
     ): boolean;
 
+    /**
+     * Called just before connection (or disconnect - if input is linked).
+     * A convenient place to switch to another input, or create new one.
+     * This allow for ability to automatically add slots if needed
+     * @param inputIndex
+     * @return selected input slot index, can differ from parameter value
+     */
+    onBeforeConnectInput?(
+        inputIndex: number
+    ): number;
+    
     /** a connection changed (new one or removed) (LiteGraph.INPUT or LiteGraph.OUTPUT, slot, true if connected, link_info, input_info or output_info ) */
     onConnectionsChange(
         type: number,

src/litegraph.js

@@ -3593,6 +3593,12 @@
             return null;
         }
 
+        if (LiteGraph.isValidConnection(output.type, input.type)) {
+            if (target_node.onBeforeConnectInput) {
+                // This way node can choose another slot (if selected is occupied)
+                target_slot = target_node.onBeforeConnectInput(target_slot);
+            }
+
             //if there is something already plugged there, disconnect
             if (target_node.inputs[target_slot].link != null) {
                 target_node.disconnectInput(target_slot);
@@ -3614,7 +3620,6 @@
             var input = target_node.inputs[target_slot];
             var link_info = null;
 
-        if (LiteGraph.isValidConnection(output.type, input.type)) {
             link_info = new LLink(
                 ++this.graph.last_link_id,
                 input.type,