Photoshop script replacing linked smart objects based on layer "name string"

This "Relink All Smart Object Layers Using New Name Prefix.jsx" variation will process all linked smart object layers found inside layer groups/nested layer groups (not only root/top-level layers):

/*
Relink All Smart Object Layers Using New Name Prefix.jsx
(Including layers in groups and nested groups)
v1.0 - 19th April 2024, Stephen Marsh
https://community.adobe.com/t5/photoshop-ecosystem-discussions/photoshop-script-replacing-linked-smart-objects-based-on-layer-quot-name-string-quot/td-p/14559920

Note: The case-insensitive colour name prefix replaces the linked file with another file in the same directory with a different colour prefix name -

From: blue_rectangle.psd
      blue_circle.psd

To:   red_rectangle.psd
      red_circle.psd

There is no need to type the underscore _ separator character (although it has to exist in the filename) and the replacement image should have the same resolution and file format as the smart objects
*/

#target photoshop

app.activeDocument.suspendHistory("Relink All Smart Object Layers Using New Name Prefix.jsx", "main()");

function main() {

    // Prompt for the colour prefix
    var thePrefix = prompt("Enter the new linked filename prefix:", "red");
    if (thePrefix === null) {
        //alert('Script cancelled!');
        //app.beep();
        return
    }
    processAllLayersAndSets(app.activeDocument);


    ///// FUNCTIONS /////

    function getSmartObjectReference() {
        // https://stackoverflow.com/questions/63010107/get-a-smart-objects-layers-files-directory-source-in-jsx
        try {
            var smartObject = {
                found: false,
                fileRef: '',
                filePath: '',
                linked: false,
            };
            var ref, so;
            ref = new ActionReference();
            ref.putProperty(charIDToTypeID("Prpr"), stringIDToTypeID("smartObject"));
            ref.putEnumerated(charIDToTypeID("Lyr "), charIDToTypeID("Ordn"), charIDToTypeID("Trgt"));
            so = executeActionGet(ref).getObjectValue(stringIDToTypeID("smartObject"));
            smartObject.found = true;
            smartObject.linked = so.getBoolean(stringIDToTypeID("linked"));
            smartObject.fileRef = so.getString(stringIDToTypeID("fileReference"));
            if (smartObject.linked) {
                smartObject.filePath = so.getPath(stringIDToTypeID("link"));
            } else {
                smartObject.filePath = Folder.temp + '/' + smartObject.fileRef;
            }
            return smartObject;
        } catch (e) {
            alert(e);
            return smartObject;
        }
    }

    function processAllLayersAndSets(obj) {
        // Process all layers and layer sets
        // Change the following 2 entries of "obj.artLayers" to "obj.layers" to include layer sets
        for (var al = obj.artLayers.length - 1; 0 <= al; al--) {
            app.activeDocument.activeLayer = obj.artLayers[al];
            relink();
        }
        // Process Layer Set Layers 
        for (var ls = obj.layerSets.length - 1; 0 <= ls; ls--) {
            processAllLayersAndSets(obj.layerSets[ls]);
            relink();
        }
    }

    function relink() {
        if (app.activeDocument.activeLayer.kind == LayerKind.SMARTOBJECT) {
            // Conditional check for linked SO
            var ref = new ActionReference();
            ref.putProperty(charIDToTypeID("Prpr"), stringIDToTypeID("smartObject"));
            ref.putEnumerated(charIDToTypeID("Lyr "), charIDToTypeID("Ordn"), charIDToTypeID("Trgt"));
            var so = executeActionGet(ref).getObjectValue(stringIDToTypeID("smartObject"));
            if (so.getBoolean(stringIDToTypeID("linked"))) {
                // Set the file path and name variables
                var thePath = getSmartObjectReference().filePath.toString().replace(/(^.+\/)(.+)/, '$1');
                //alert(thePath);
                var theName = getSmartObjectReference().filePath.fsName.toString().replace(/(^.+?)(_.+)/, '$2');
                //alert(theName);
                var theAD = new ActionDescriptor();
                //alert((thePath + thePrefix + theName));
                // Relink to the new file 
                theAD.putPath(stringIDToTypeID("null"), new File(thePath + thePrefix + theName));
                executeAction(stringIDToTypeID("placedLayerRelinkToFile"), theAD, DialogModes.NO);
            }
        }
    }
}