Remade lost changes

src/litegraph.d.ts

@@ -740,7 +740,7 @@ export declare class LGraphNode {
         name: string,
         type: string | -1,
         extra_info?: Partial<INodeOutputSlot>
-    ): void;
+    ): INodeOutputSlot;
     /**
      * add a new output slot to use in this node
      * @param array of triplets like [[name,type,extra_info],[...]]
@@ -760,7 +760,7 @@ export declare class LGraphNode {
         name: string,
         type: string | -1,
         extra_info?: Partial<INodeInputSlot>
-    ): void;
+    ): INodeInputSlot;
     /**
      * add several new input slots in this node
      * @param array of triplets like [[name,type,extra_info],[...]]
@@ -953,13 +953,34 @@ export declare class LGraphNode {
     /**
      * if returns false the incoming connection will be canceled
      * Called by `LGraph.connect`
+     * @param inputIndex target input slot number
+     * @param outputType type of output slot
+     * @param outputSlot output slot object
+     * @param outputNode node containing the output
+     * @param outputIndex index of output slot
      */
     onConnectInput?(
         inputIndex: number,
-        type: INodeOutputSlot["type"],
+        outputType: INodeOutputSlot["type"],
         outputSlot: INodeOutputSlot,
-        _this: this,
-        slotIndex: number
+        outputNode: LGraphNode,
+        outputIndex: number
+    ): boolean;
+    /**
+     * if returns false the incoming connection will be canceled
+     * Called by `LGraph.connect`
+     * @param outputIndex target output slot number
+     * @param inputType type of input slot
+     * @param inputSlot input slot object
+     * @param inputNode node containing the input
+     * @param inputIndex index of input slot
+     */
+    onConnectOutput?(
+        outputIndex: number,
+        inputType: INodeInputSlot["type"],
+        inputSlot: INodeInputSlot,
+        inputNode: LGraphNode,
+        inputIndex: number
     ): boolean;
 
     /**

src/litegraph.js

@@ -3685,43 +3685,37 @@
         }
 
 		var changed = false;
+        var input = target_node.inputs[target_slot];
+        var output = this.outputs[slot];
+        var link_info = 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) {
-			this.graph.beforeChange();
                 target_node.disconnectInput(target_slot);
-			changed = true;
             }
 
             //why here??
             //this.setDirtyCanvas(false,true);
             //this.graph.connectionChange( this );
 
-        var output = this.outputs[slot];
-
             //allows nodes to block connection
             if (target_node.onConnectInput) {
                 if ( target_node.onConnectInput(target_slot, output.type, output, this, slot) === false ) {
                     return null;
                 }
             }
-
-        var input = target_node.inputs[target_slot];
-        var link_info = null;
-
-		//this slots cannot be connected (different types)
-        if (!LiteGraph.isValidConnection(output.type, input.type))
-		{
-	        this.setDirtyCanvas(false, true);
-			if(changed)
-		        this.graph.connectionChange(this, link_info);
+            if (this.onConnectOutput) {
+                if ( this.onConnectOutput(slot, input.type, input, target_node, target_slot) === false ) {
                     return null;
                 }
+            }
 
-		if(!changed)
-			this.graph.beforeChange();
-
-		//create link class
             link_info = new LLink(
                 ++this.graph.last_link_id,
                 input.type,
@@ -3778,6 +3772,7 @@
                     target_slot
                 );
             }
+        }
 
         this.setDirtyCanvas(false, true);
 		this.graph.afterChange();