From dd696296255d8e232054b65054c90a9e6c538bfa Mon Sep 17 00:00:00 2001
From: Tim Hansen <timbonicus@gmail.com>
Date: Mon, 21 Jun 2021 11:28:09 -0600
Subject: [PATCH] Use query params with useEntityListProvider

Signed-off-by: Tim Hansen <timbonicus@gmail.com>
---
 .../EntityKindPicker/EntityKindPicker.tsx     |  7 +++++--
 plugins/catalog-react/src/filters.ts          |  4 ++++
 .../src/hooks/useEntityListProvider.tsx       | 21 +++++++++++++++++++
 plugins/catalog-react/src/types.ts            |  7 +++++++
 4 files changed, 37 insertions(+), 2 deletions(-)

diff --git a/plugins/catalog-react/src/components/EntityKindPicker/EntityKindPicker.tsx b/plugins/catalog-react/src/components/EntityKindPicker/EntityKindPicker.tsx
index 92831ea252..5b3f95b7ba 100644
--- a/plugins/catalog-react/src/components/EntityKindPicker/EntityKindPicker.tsx
+++ b/plugins/catalog-react/src/components/EntityKindPicker/EntityKindPicker.tsx
@@ -28,8 +28,11 @@ export const EntityKindPicker = ({
   initialFilter,
   hidden,
 }: EntityKindFilterProps) => {
-  const [selectedKind] = useState(initialFilter);
-  const { updateFilters } = useEntityListProvider();
+  const { updateFilters, queryParameters } = useEntityListProvider();
+  const [selectedKind] = useState(
+    // TODO Cast here is not great 🤔
+    (queryParameters.kind as string) ?? initialFilter,
+  );
 
   useEffect(() => {
     updateFilters({
diff --git a/plugins/catalog-react/src/filters.ts b/plugins/catalog-react/src/filters.ts
index 9b57e0f560..2b23031cc9 100644
--- a/plugins/catalog-react/src/filters.ts
+++ b/plugins/catalog-react/src/filters.ts
@@ -29,6 +29,10 @@ export class EntityKindFilter implements EntityFilter {
   getCatalogFilters(): Record<string, string | string[]> {
     return { kind: this.value };
   }
+
+  toQueryValue(): string {
+    return this.value;
+  }
 }
 
 export class EntityTypeFilter implements EntityFilter {
diff --git a/plugins/catalog-react/src/hooks/useEntityListProvider.tsx b/plugins/catalog-react/src/hooks/useEntityListProvider.tsx
index 33c951acce..253184a851 100644
--- a/plugins/catalog-react/src/hooks/useEntityListProvider.tsx
+++ b/plugins/catalog-react/src/hooks/useEntityListProvider.tsx
@@ -77,6 +77,11 @@ export type EntityListContextProps<
       | ((prevFilters: EntityFilters) => Partial<EntityFilters>),
   ) => void;
 
+  /**
+   * Filter values from query parameters.
+   */
+  queryParameters: Record<keyof EntityFilters, string | string[]>;
+
   loading: boolean;
   error?: Error;
 };
@@ -89,6 +94,7 @@ type OutputState<EntityFilters extends DefaultEntityFilters> = {
   appliedFilters: EntityFilters;
   entities: Entity[];
   backendEntities: Entity[];
+  queryParameters: Record<string, string | string[]>;
 };
 
 export const EntityListProvider = <EntityFilters extends DefaultEntityFilters>({
@@ -102,6 +108,7 @@ export const EntityListProvider = <EntityFilters extends DefaultEntityFilters>({
     appliedFilters: {} as EntityFilters,
     entities: [],
     backendEntities: [],
+    queryParameters: {}, // TODO: Load (once!!) from query parameters
   });
 
   // The main async filter worker. Note that while it has a lot of dependencies
@@ -116,6 +123,15 @@ export const EntityListProvider = <EntityFilters extends DefaultEntityFilters>({
         compact(Object.values(outputState.appliedFilters)),
       );
 
+      const queryParams = Object.keys(requestedFilters).reduce((params, key) => {
+        const filter: EntityFilter | undefined =
+          requestedFilters[key as keyof EntityFilters];
+        if (filter?.toQueryValue) {
+          params[key] = filter.toQueryValue();
+        }
+        return params;
+      }, {} as Record<string, string | string[]>);
+
       // TODO(mtlewis): currently entities will never be requested unless
       // there's at least one filter, we should allow an initial request
       // to happen with no filters.
@@ -129,14 +145,18 @@ export const EntityListProvider = <EntityFilters extends DefaultEntityFilters>({
           appliedFilters: requestedFilters,
           backendEntities: response.items,
           entities: response.items.filter(entityFilter),
+          queryParameters: queryParams,
         });
       } else {
         setOutputState({
           appliedFilters: requestedFilters,
           backendEntities: outputState.backendEntities,
           entities: outputState.backendEntities.filter(entityFilter),
+          queryParameters: queryParams,
         });
       }
+
+      // TODO: write queryParams to query string
     },
     [catalogApi, requestedFilters, outputState],
     { loading: true },
@@ -168,6 +188,7 @@ export const EntityListProvider = <EntityFilters extends DefaultEntityFilters>({
         entities: outputState.entities,
         backendEntities: outputState.backendEntities,
         updateFilters,
+        queryParameters: outputState.queryParameters,
         loading,
         error,
       }}
diff --git a/plugins/catalog-react/src/types.ts b/plugins/catalog-react/src/types.ts
index 68c11d7f38..4ac7644ee1 100644
--- a/plugins/catalog-react/src/types.ts
+++ b/plugins/catalog-react/src/types.ts
@@ -34,6 +34,13 @@ export type EntityFilter = {
    * @param env
    */
   filterEntity?: (entity: Entity) => boolean;
+
+  /**
+   * Serialize the filter value to a string for query params. The UI component responsible for
+   * handling this filter should retrieve this from useEntityListProvider.queryParameters. The
+   * value restored should be in the precedence: queryParameters > initialValue prop > default.
+   */
+  toQueryValue?: () => string | string[];
 };
 
 export type UserListFilterKind = 'owned' | 'starred' | 'all';