utils for articles

src/blog/utils/articles.ts

@@ -0,0 +1,76 @@
+import {
+  ArticleModel,
+  ArticleRepoModel
+} from "../types/models";
+
+// List helpers
+export function createInList(list: ArticleModel[], a: ArticleModel) {
+  return [a, ...list];
+}
+
+export function readInList(list: ArticleModel[], index: number) {
+  if (index < 0 || index >= list.length) {
+    // Soft fallback
+    return undefined;
+  }
+  return list[index];
+}
+
+export function updateInList(list: ArticleModel[], a: ArticleModel) {
+  return list.map(x => (x._id === a._id ? a : x));
+}
+
+export function deleteInList(list: ArticleModel[], id: string) {
+  return list.filter(x => x._id !== id);
+}
+
+// Map helpers
+export function createById(
+  map: Record<string, ArticleModel>,
+  a: ArticleModel
+) {
+  if (!a._id) {
+    // Soft mode: ignore create, return unchanged
+    return map;
+  }
+
+  if (map[a._id]) {
+    // Soft mode: do not replace existing
+    return map;
+  }
+
+  return { ...map, [a._id]: a };
+}
+
+export function readById(
+  map: Record<string, ArticleModel>,
+  id: string
+) {
+  if (!id) return undefined;
+  return map[id];
+}
+
+export function updateById(
+  map: Record<string, ArticleModel>,
+  a: ArticleModel
+) {
+  if (!a._id) {
+    // Cannot update without ID
+    return map;
+  }
+
+  if (!map[a._id]) {
+    // ID does not exist → soft mode: do nothing
+    return map;
+  }
+
+  return { ...map, [a._id]: a };
+}
+
+export function deleteById(
+  map: Record<string, ArticleModel>,
+  id: string
+) {
+  const { [id]: _, ...rest } = map;
+  return rest;
+}