Initial commit

Co-Authored-By: Eric Tuvesson <eric.tuvesson@gmail.com>
Co-Authored-By: mikaeltellhed <2311083+mikaeltellhed@users.noreply.github.com>
Co-Authored-By: kotte <14197736+mrtamagotchi@users.noreply.github.com>
Co-Authored-By: Anders Larsson <64838990+anders-topp@users.noreply.github.com>
Co-Authored-By: Johan  <4934465+joolsus@users.noreply.github.com>
Co-Authored-By: Tore Knudsen <18231882+torekndsn@users.noreply.github.com>
Co-Authored-By: victoratndl <99176179+victoratndl@users.noreply.github.com>

packages/noodl-runtime/src/variants.js

@@ -0,0 +1,42 @@
+class Variants {
+
+    constructor({graphModel, getNodeScope}) {
+        this.getNodeScope = getNodeScope;
+
+        if(graphModel) {
+            this.graphModel = graphModel;
+            graphModel.on('variantUpdated', variant => this.onVariantUpdated(variant));
+        }
+    }
+
+    getVariant(typename, name) {
+        if(!this.graphModel) return undefined;
+        
+        return this.graphModel.getVariant(typename, name);
+    }
+
+    onVariantUpdated(variant) {
+        const nodeScope = this.getNodeScope();
+        if(!nodeScope) return;
+
+        //get all nodes with the type the variant applies to
+        const nodes = nodeScope.getNodesWithTypeRecursive(variant.typename);
+
+        //and filter for the ones using the updated variant
+        const nodesWithVariant = nodes.filter(node => {
+
+            //if a variant has been set during runtime, it'll override the value from the model
+            if(node.variant) return node.variant.name === variant.name;
+
+            //otherwise check the model (which always matches the editor)
+            return node.model && node.model.variant === variant.name;
+        });
+
+        //and re-apply the variant
+        for(const node of nodesWithVariant) {
+            node.setVariant(variant);
+        }
+    }
+}
+
+module.exports = Variants;