Create a derived atom for dataset hydration from Next.js, expose it i…

…n the veda lib

app/scripts/components/exploration/atoms/datasetLayers.ts

@@ -0,0 +1,27 @@
+import { atom } from 'jotai';
+import { DatasetLayer } from '$types/veda';
+
+/**
+ * This is the primary storage atom for external datasets (e.g. passed from Next.js).
+ */
+export const externalDatasetsAtom = atom<any[]>([]);
+
+/**
+ * Derived atom that transforms the provided datasets into layers.
+ * It is used by the timelineDatasetsAtom to rebuild state from URL parameters
+ * while it preserves the parent dataset metadata for each layer that comes
+ * from the MDX configuration.
+ */
+export const datasetLayersAtom = atom<DatasetLayer[]>((get) => {
+  const datasets = get(externalDatasetsAtom);
+
+  return datasets.flatMap((dataset) => {
+    return (dataset.layers || []).map((l: any) => ({
+      ...l,
+      parentDataset: {
+        id: dataset.id,
+        name: dataset.name
+      }
+    }));
+  });
+});

app/scripts/components/exploration/atoms/datasets.ts

@@ -1,6 +1,6 @@
-import { datasetLayers } from '../data-utils';
 import { reconcileDatasets } from '../data-utils-no-faux-module';
 import { TimelineDataset, TimelineDatasetForUrl } from '../types.d.ts';
+import { datasetLayersAtom } from './datasetLayers';
 import { atomWithUrlValueStability } from '$utils/params-location-atom/atom-with-url-value-stability';
 
 function urlDatasetsDehydrate(datasets: TimelineDataset[]) {
@@ -38,7 +38,7 @@ export const timelineDatasetsAtom = atomWithUrlValueStability<
   dehydrate: (datasets) => {
     return urlDatasetsDehydrate(datasets);
   },
-  reconcile: (urlDatasets, storageDatasets) => {
+  reconcile: (urlDatasets, storageDatasets, get) => {
     // Reconcile what needs to be reconciled.
     const reconciledDatasets = urlDatasets.map((enc) => {
       // We only want to do this on load. If the dataset was already
@@ -49,10 +49,14 @@ export const timelineDatasetsAtom = atomWithUrlValueStability<
       if (readyDataset) {
         return readyDataset;
       }
+      const currentDatasetLayers = get(datasetLayersAtom);
       // Reconcile the dataset with the internal data (from VEDA config files)
       // and then add the url stored settings.
-      // @TODO - replace datasetLayers
-      const [reconciled] = reconcileDatasets([enc.id], datasetLayers, []);
+      const [reconciled] = reconcileDatasets(
+        [enc.id],
+        currentDatasetLayers,
+        []
+      );
       if (enc.settings) {
         reconciled.settings = enc.settings;
       }

app/scripts/components/exploration/hooks/use-timeline-dataset-atom.tsx

@@ -2,10 +2,10 @@ import { useAtom } from 'jotai';
 import { timelineDatasetsAtom } from '../atoms/datasets';
 import { TimelineDataset } from '../types.d.ts';
 
-export default function useTimelineDatasetAtom (): [
+export default function useTimelineDatasetAtom(): [
   TimelineDataset[],
   (datasets: TimelineDataset[]) => void
-]  {
+] {
   const [datasets, setDatasets] = useAtom(timelineDatasetsAtom);
   return [datasets, setDatasets];
-}
+}

app/scripts/index.ts

@@ -29,6 +29,10 @@ import useTimelineDatasetAtom from '$components/exploration/hooks/use-timeline-d
 import { timelineDatasetsAtom } from '$components/exploration/atoms/datasets';
 import { DatasetSelectorModal } from '$components/exploration/components/dataset-selector-modal';
 import { EnvConfigProvider } from '$context/env-config';
+import {
+  datasetLayersAtom,
+  externalDatasetsAtom
+} from '$components/exploration/atoms/datasetLayers';
 
 // Adding .last property to array
 /* eslint-disable-next-line fp/no-mutating-methods */
@@ -77,5 +81,7 @@ export {
   InternalNavLink,
 
   // STATE
-  timelineDatasetsAtom
+  timelineDatasetsAtom,
+  externalDatasetsAtom,
+  datasetLayersAtom
 };

app/scripts/utils/params-location-atom/atom-with-url-value-stability.ts

@@ -57,10 +57,15 @@ interface StableAtomOptions<Value, ValueUrl> {
    * the information that goes to the url needs to be simplified.
    * @param urlValue The value stored in the URL parameter after hydration.
    * @param storageValue The value stored in the atom.
+   * @param get A getter function to access other atom values during reconciliation.
    * @returns The reconciled value. If the function is not provided the urlValue
    * is considered the reconciled value.
    */
-  reconcile?: (urlValue: ValueUrl, storageValue: Value) => Value;
+  reconcile?: (
+    urlValue: ValueUrl,
+    storageValue: Value,
+    get: (atom: any) => any
+  ) => Value;
   /**
    * An optional function to compare two atom values for equality.
    * @param prev The previous atom value.
@@ -93,7 +98,7 @@ export function atomWithUrlValueStability<T, TUrl = T>(
       const storageValue = get(storage);
 
       // Reconcile the hydrated value with the storage value.
-      const reconciled = reconcile(hydrated, storageValue);
+      const reconciled = reconcile(hydrated, storageValue, get);
 
       // If the reconciled value is equal to the storage value, return the
       // storage value to ensure equality.