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lib/hierarchy-model.ts

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+import { types } from "mobx-state-tree";
+
+/**
+ * Reusable abstraction for a domain/sector hierarchy.
+ * Works for both v1 and v2
+ */
+export const HierarchyModel = types.model("HierarchyModel", {
+    version: types.string,                 // "v1" | "v2"
+    domain: types.string,                  // e.g. "Finance", "Technology"
+    structure: types.array(types.string),  // ordered hierarchy labels
+    description: types.string,             // plain-text description
+    commonSkills: types.array(types.string),
+    commonTools: types.array(types.string),
+    examples: types.array(types.string)
+});
+
+/* ------------------------------------------------------------------ *
+ * Example usage
+ * ------------------------------------------------------------------ */
+
+// Create individual instances
+// import { HierarchyModel } from "./hierarchy-model";
+//
+// const finance = HierarchyModel.create(v1Finance);
+// const tech = HierarchyModel.create(v2Tech);
+
+export const HierarchyStore = types
+    .model("HierarchyStore", {
+        items: types.map(HierarchyModel)     // keyed by domain name
+    })
+    .actions(self => ({
+        add(h: Instance<typeof HierarchyModel>) {
+            self.items.set(h.domain, h);
+        }
+    }));