tmp

sitemap-parser/src/createSitemap.spec.ts

@@ -1,5 +1,5 @@
-import { createSitemap } from './createSitemap';
-import { ApiResponse, Sitemap } from './types';
+import { TypedSitemap, createSitemap } from './createSitemap';
+import { ApiResponse, PathsResolver, Paths, ResolverForPaths, Sitemap, Simplify } from './types';
 
 describe('createSitemap', () => {
     it('creates correct sitemap for sample data', () => {
@@ -16,6 +16,24 @@ describe('createSitemap', () => {
             { id: 10, slug: 'children', parent: 8 },
         ] as const satisfies ApiResponse;
 
+        const x: TypedSitemap<typeof sampleInput> = null as any;
+        const y: Simplify<Paths<typeof x>> = null as any;
+        if (y[0] === '/') {
+            let f = y[1]
+        }
+        const z: ResolverForPaths<typeof y> = null as any;
+        const a = z('/books/children')
+        const b = z('huihuoj');
+        const z2: PathsResolver<typeof x> = null as any;
+        const m = z2('/');
+        //const c = z2('');
+        const d = z2('abc');
+        const e = z2('/');
+        //const z: Sitemap = x;
+
+        const f = sampleInput as ApiResponse;
+        const g: TypedSitemap<ApiResponse> = null as any;
+
         const sampleOutput = {
             name: 'root',
             id: 1,

sitemap-parser/src/createSitemap.ts

@@ -1,4 +1,4 @@
-import { ApiResponse, Sitemap } from './types';
+import { ApiResponse, Sitemap, Simplify } from './types';
 
 type Subtree = {
     name: string;
@@ -6,10 +6,35 @@ type Subtree = {
     children: Sitemap[];
 };
 
+type GetBaseParentIdType<TParentId extends number | null> = TParentId extends null ? null : number;
+
+type ExtractEntryByParentId<TEntry extends ApiResponse[number], TParentId extends number | null> = 
+    //Extract<TEntry, { readonly parent: TParentId }>;
+    Simplify<{ readonly parent: GetBaseParentIdType<TParentId> } extends Pick<TEntry, 'parent'> ? TEntry : Extract<TEntry, { readonly parent: TParentId }>>;
+
+type ExtractEntriesByParentId<TApiResponse extends ApiResponse, TParentId extends number | null> = ExtractEntryByParentId<TApiResponse[number], TParentId>;
+
+type TypedSitemapEntry<TApiResponse extends ApiResponse, TEntry extends TApiResponse[number]> = TEntry extends unknown ? {
+    name: TEntry['slug'],
+    id: TEntry['id'],
+    children: TypedSitemapEntries<TApiResponse, TEntry['id']>
+} : never;
+
+type TypedSitemapEntries<TApiResponse extends ApiResponse, TParentId extends number | null> = TypedSitemapEntry<TApiResponse, ExtractEntriesByParentId<TApiResponse, TParentId>>[];
+
+//type NeverToNull<TSitemap> = TSitemap extends never ? null : TSitemap;
+
+//export type TypedSitemap<TApiResponse extends ApiResponse> = Simplify<NeverToNull<Simplify<TypedSitemapEntries<TApiResponse, null>[number]>>>;
+export type TypedSitemap<TApiResponse extends ApiResponse> = Simplify<TypedSitemapEntries<TApiResponse, null>[number]>;
+
+//const z = [{slug: 'a', id: 1, parent: 1 }];
+//type Q = NeverToNull<TypedSitemap<typeof z>>;
+//type A = never extends never ? 'a' : 'b';
+
 // alternatively, for full TS experience, if I had more time I'd also implement parsing in TS so that this declaration would look like:
 // export const createSitemap = <TResponse extends ApiResponse>(apiResponse: TResponse): Sitemap<TResponse> => {
 // and calling e.g. `createSitemap(const sample data json)` would return value with type `const sample sitemap`, rather than just general sitemap
-export const createSitemap = (apiResponse: ApiResponse): Sitemap | null => {
+export const createSitemap = <TResponse extends ApiResponse>(apiResponse: ApiResponse): TypedSitemap<TResponse> => {
     const subtrees = new Map<number, Subtree>(
         apiResponse.map(({ id, slug }) => [
             id,
@@ -36,5 +61,5 @@ export const createSitemap = (apiResponse: ApiResponse): Sitemap | null => {
         }
     }
 
-    return root;
+    return root as any;
 };

sitemap-parser/src/resolveByPath.ts

@@ -16,19 +16,20 @@ import { Sitemap } from './types';
         );
     };*/
 
-const createPaths = (node: Sitemap): Readonly<[string, number]>[] => [
-    ['', node.id],
+const createPaths = (
+    node: Sitemap,
+    prefix: string,
+): Readonly<[string, number]>[] => [
+    [prefix, node.id],
     ...node.children.flatMap((childNode) =>
-        createPaths(childNode).map(
-            ([path, id]) => [`/${childNode.name}${path}`, id] as const,
-        ),
+        createPaths(childNode, `${prefix}/${childNode.name}`),
     ),
 ];
 
 // Second, improved implementation, where we build a static hashmap from complete paths to IDs once,
 // and then use it as a single lookup table.
 export const createPathResolver = (sitemap: Sitemap | null) => {
-    const rawPathsData = sitemap ? createPaths(sitemap) : [];
+    const rawPathsData = sitemap ? createPaths(sitemap, '') : [];
     const pathsMap = new Map(
         rawPathsData.map(([path, id]) => [path.length ? path : '/', id]),
     );

sitemap-parser/src/types.ts

@@ -7,7 +7,30 @@ export type ApiResponse = Readonly<
 >;
 
 export type Sitemap = Readonly<{
-    name: string;
-    id: number;
-    children: readonly Sitemap[];
+    readonly name: string;
+    readonly id: number;
+    readonly children: readonly Sitemap[];
 }>;
+
+export type Simplify<T> = T extends Record<string, unknown> | unknown[]
+  ? T extends infer O
+    ? { [K in keyof O]: Simplify<O[K]> }
+    : never
+  : T;
+
+type PathsForEntry<TEntry extends Sitemap, TPrefix extends string> = TEntry extends unknown ? [`${TPrefix}/${TEntry['name']}`, TEntry['id']] | PathsForEntry<TEntry['children'][number], `${TPrefix}/${TEntry['name']}`> : never;
+
+export type Paths<TSitemap extends Sitemap> = Simplify<PathsForEntry<TSitemap['children'][number], ''> | ['/', TSitemap['id']]>;
+
+type Mew<T> = T extends readonly [string, number] ? T : never;
+
+type ResetStack<T> = T extends infer R ? R & readonly [string, number] : never;
+
+export type ResolverForPaths<TPaths extends readonly [string, number]> = {
+    <TPath extends TPaths[0]>(path: TPath): Extract<TPaths, readonly [TPath, number]>[1];
+    (unknownPath: string): null;
+};
+
+export type PathsResolver<TSitemap extends Sitemap> = ResolverForPaths<Extract<Paths<TSitemap> extends infer R ? R : never, readonly [string, number]>>;
+
+//export type PathsResolver<TSitemap extends Sitemap> = ResolverForPaths<Paths<TSitemap>>;