5043 Move ELK to standalone package

packages/mermaid-flowchart-elk/src/detector.ts

@@ -0,0 +1,32 @@
+import type {
+  ExternalDiagramDefinition,
+  DiagramDetector,
+  DiagramLoader,
+} from '../../mermaid/src/diagram-api/types.js';
+
+const id = 'flowchart-elk';
+
+const detector: DiagramDetector = (txt, config): boolean => {
+  if (
+    // If diagram explicitly states flowchart-elk
+    /^\s*flowchart-elk/.test(txt) ||
+    // If a flowchart/graph diagram has their default renderer set to elk
+    (/^\s*flowchart|graph/.test(txt) && config?.flowchart?.defaultRenderer === 'elk')
+  ) {
+    return true;
+  }
+  return false;
+};
+
+const loader: DiagramLoader = async () => {
+  const { diagram } = await import('./diagram-definition.js');
+  return { id, diagram };
+};
+
+const plugin: ExternalDiagramDefinition = {
+  id,
+  detector,
+  loader,
+};
+
+export default plugin;