feat(editor): ERD arrowheads and diagrams (#10940)

packages/element/src/arrowheads.ts

@@ -0,0 +1,32 @@
+import type { Arrowhead, AnyArrowhead } from "./types";
+
+export const normalizeArrowhead = (
+  arrowhead: AnyArrowhead | null | undefined,
+): Arrowhead | null => {
+  switch (arrowhead) {
+    case undefined:
+    case null:
+      return null;
+    case "dot":
+      return "circle";
+    case "crowfoot_one":
+      return "cardinality_one";
+    case "crowfoot_many":
+      return "cardinality_many";
+    case "crowfoot_one_or_many":
+      return "cardinality_one_or_many";
+    default:
+      return arrowhead;
+  }
+};
+
+export const getArrowheadForPicker = (
+  arrowhead: AnyArrowhead | null | undefined,
+): Arrowhead | null => {
+  const normalizedArrowhead = normalizeArrowhead(arrowhead);
+  if (normalizedArrowhead === null) {
+    return null;
+  }
+
+  return normalizedArrowhead;
+};