TASKS-1823 WebManager module

apps/backend/app/base_modules/WebManager/services/breadcrumb_paths.ts

@@ -0,0 +1,50 @@
+import { BREADCRUMB_PAGE_TYPE_PARENTS } from '#base_modules/WebManager/config/general'
+
+/**
+ * Utility functions that identify candidate pages for buildBreadcrumbs database queries.
+ * Breadcrumbs climb hierarchically from a target page to the home page.
+ * To avoid querying all published pages in a locale, queries are filtered down to two
+ * predictable sets of candidates:
+ *  1. Path-based ancestors: The small chain of parent paths above the target page.
+ *  2. Group-key ancestors: Static relationships where pages belong to a specific parent
+ *     type regardless of location (e.g., blog-item under blog).
+ */
+
+export const BREADCRUMB_PARENT_GROUP_KEYS = [
+  ...new Set(Object.values(BREADCRUMB_PAGE_TYPE_PARENTS)),
+]
+
+/**
+ * The paths a page can climb to, nearest parent first, ending at the home page (`''`).
+ *
+ *   'blog/post/hello' → ['blog/post', 'blog', '']
+ *   'about'           → ['']
+ *   ''                → ['']
+ *
+ * The page's own path is never included — a page cannot be its own parent.
+ */
+export function ancestorPaths(path: string) {
+  const segments = path.split('/').filter(Boolean)
+  const paths: string[] = []
+
+  for (let depth = segments.length - 1; depth >= 1; depth--) {
+    paths.push(segments.slice(0, depth).join('/'))
+  }
+
+  paths.push('')
+
+  return paths
+}
+
+/**
+ * True when `path` is an already loaded path or an ancestor of one. Only false after a
+ * group-key jump to another branch, never during a path climb.
+ */
+export function ancestorsAlreadyLoaded(path: string, loadedPaths: Iterable<string>) {
+  for (const loaded of loadedPaths) {
+    // The trailing slash keeps 'blog' from matching 'blogging'; '' matches every path.
+    if (loaded === path || loaded.startsWith(path === '' ? '' : `${path}/`)) return true
+  }
+
+  return false
+}