fix(files): Ensure children are removed from folder and not duplicated

* Resolves https://github.com/nextcloud/server/issues/47904

We need to make sure that we only add one source (unique!) once as a child,
this is ensured by simply use a native `Set`.
Also we need to remove children on from folders when the `files:node:deleted`
event is emitted.

Signed-off-by: Ferdinand Thiessen <opensource@fthiessen.de>

2 files changed, 64 insertions, 13 deletions

diff --git a/apps/files/src/store/paths.ts b/apps/files/src/store/paths.ts
index 2993cc9d704..8c197400eac 100644
--- a/apps/files/src/store/paths.ts
+++ b/apps/files/src/store/paths.ts
@@ -2,7 +2,7 @@
  * SPDX-FileCopyrightText: 2023 Nextcloud GmbH and Nextcloud contributors
  * SPDX-License-Identifier: AGPL-3.0-or-later
  */
-import type { FileSource, PathsStore, PathOptions, ServicesState } from '../types'
+import type { FileSource, PathsStore, PathOptions, ServicesState, Service } from '../types'
 import { defineStore } from 'pinia'
 import { FileType, Folder, Node, getNavigation } from '@nextcloud/files'
 import { subscribe } from '@nextcloud/event-bus'
@@ -41,6 +41,57 @@ export const usePathsStore = function(...args) {
 				Vue.set(this.paths[payload.service], payload.path, payload.source)
 			},
 
+			deletePath(service: Service, path: string) {
+				// skip if service does not exist
+				if (!this.paths[service]) {
+					return
+				}
+
+				Vue.delete(this.paths[service], path)
+			},
+
+			onDeletedNode(node: Node) {
+				const service = getNavigation()?.active?.id || 'files'
+
+				if (node.type === FileType.Folder) {
+					// Delete the path
+					this.deletePath(
+						service,
+						node.path,
+					)
+				}
+
+				// Remove node from children
+				if (node.dirname === '/') {
+					const root = files.getRoot(service) as Folder & { _children?: string[] }
+					// ensure sources are unique
+					const children = new Set(root._children ?? [])
+					children.delete(node.source)
+					Vue.set(root, '_children', [...children.values()])
+					return
+				}
+
+				if (this.paths[service][node.dirname]) {
+					const parentSource = this.paths[service][node.dirname]
+					const parentFolder = files.getNode(parentSource) as Folder & { _children?: string[] }
+
+					if (!parentFolder) {
+						logger.error('Parent folder not found', { parentSource })
+						return
+					}
+
+					logger.debug('Path exists, removing from children', { parentFolder, node })
+
+					// ensure sources are unique
+					const children = new Set(parentFolder._children ?? [])
+					children.delete(node.source)
+					Vue.set(parentFolder, '_children', [...children.values()])
+					return
+				}
+
+				logger.debug('Parent path does not exists, skipping children update', { node })
+			},
+
 			onCreatedNode(node: Node) {
 				const service = getNavigation()?.active?.id || 'files'
 				if (!node.fileid) {
@@ -60,11 +111,11 @@ export const usePathsStore = function(...args) {
 				// Update parent folder children if exists
 				// If the folder is the root, get it and update it
 				if (node.dirname === '/') {
-					const root = files.getRoot(service)
-					if (!root._children) {
-						Vue.set(root, '_children', [])
-					}
-					root._children.push(node.source)
+					const root = files.getRoot(service) as Folder & { _children?: string[] }
+					// ensure sources are unique
+					const children = new Set(root._children ?? [])
+					children.add(node.source)
+					Vue.set(root, '_children', [...children.values()])
 					return
 				}
 
@@ -72,7 +123,7 @@ export const usePathsStore = function(...args) {
 				// fetched later and its children updated anyway.
 				if (this.paths[service][node.dirname]) {
 					const parentSource = this.paths[service][node.dirname]
-					const parentFolder = files.getNode(parentSource) as Folder
+					const parentFolder = files.getNode(parentSource) as Folder & { _children?: string[] }
 					logger.debug('Path already exists, updating children', { parentFolder, node })
 
 					if (!parentFolder) {
@@ -80,10 +131,10 @@ export const usePathsStore = function(...args) {
 						return
 					}
 
-					if (!parentFolder._children) {
-						Vue.set(parentFolder, '_children', [])
-					}
-					parentFolder._children.push(node.source)
+					// ensure sources are unique
+					const children = new Set(parentFolder._children ?? [])
+					children.add(node.source)
+					Vue.set(parentFolder, '_children', [...children.values()])
 					return
 				}
 
@@ -97,7 +148,7 @@ export const usePathsStore = function(...args) {
 	if (!pathsStore._initialized) {
 		// TODO: watch folders to update paths?
 		subscribe('files:node:created', pathsStore.onCreatedNode)
-		// subscribe('files:node:deleted', pathsStore.onDeletedNode)
+		subscribe('files:node:deleted', pathsStore.onDeletedNode)
 		// subscribe('files:node:moved', pathsStore.onMovedNode)
 
 		pathsStore._initialized = true
diff --git a/apps/files/src/views/FilesList.vue b/apps/files/src/views/FilesList.vue
index c7574c8a7a7..7700cf92382 100644
--- a/apps/files/src/views/FilesList.vue
+++ b/apps/files/src/views/FilesList.vue
@@ -651,7 +651,7 @@ export default defineComponent({
 		},
 
 		filterDirContent() {
-			let nodes = this.dirContents
+			let nodes: INode[] = this.dirContents
 			for (const filter of this.filtersStore.sortedFilters) {
 				nodes = filter.filter(nodes)
 			}