1 files changed, 82 insertions, 0 deletions
diff --git a/web_src/js/modules/diff-file.ts b/web_src/js/modules/diff-file.ts
new file mode 100644
index 0000000000..2cec7bc6b3
--- /dev/null
+++ b/web_src/js/modules/diff-file.ts
@@ -0,0 +1,82 @@
+import {reactive} from 'vue';
+import type {Reactive} from 'vue';
+
+const {pageData} = window.config;
+
+export type DiffStatus = '' | 'added' | 'modified' | 'deleted' | 'renamed' | 'copied' | 'typechange';
+
+export type DiffTreeEntry = {
+  FullName: string,
+  DisplayName: string,
+  NameHash: string,
+  DiffStatus: DiffStatus,
+  EntryMode: string,
+  IsViewed: boolean,
+  Children: DiffTreeEntry[],
+  FileIcon: string,
+  ParentEntry?: DiffTreeEntry,
+}
+
+type DiffFileTreeData = {
+  TreeRoot: DiffTreeEntry,
+};
+
+type DiffFileTree = {
+  folderIcon: string;
+  folderOpenIcon: string;
+  diffFileTree: DiffFileTreeData;
+  fullNameMap?: Record<string, DiffTreeEntry>
+  fileTreeIsVisible: boolean;
+  selectedItem: string;
+}
+
+let diffTreeStoreReactive: Reactive<DiffFileTree>;
+export function diffTreeStore() {
+  if (!diffTreeStoreReactive) {
+    diffTreeStoreReactive = reactiveDiffTreeStore(pageData.DiffFileTree, pageData.FolderIcon, pageData.FolderOpenIcon);
+  }
+  return diffTreeStoreReactive;
+}
+
+export function diffTreeStoreSetViewed(store: Reactive<DiffFileTree>, fullName: string, viewed: boolean) {
+  const entry = store.fullNameMap[fullName];
+  if (!entry) return;
+  entry.IsViewed = viewed;
+  for (let parent = entry.ParentEntry; parent; parent = parent.ParentEntry) {
+    parent.IsViewed = isEntryViewed(parent);
+  }
+}
+
+function fillFullNameMap(map: Record<string, DiffTreeEntry>, entry: DiffTreeEntry) {
+  map[entry.FullName] = entry;
+  if (!entry.Children) return;
+  entry.IsViewed = isEntryViewed(entry);
+  for (const child of entry.Children) {
+    child.ParentEntry = entry;
+    fillFullNameMap(map, child);
+  }
+}
+
+export function reactiveDiffTreeStore(data: DiffFileTreeData, folderIcon: string, folderOpenIcon: string): Reactive<DiffFileTree> {
+  const store = reactive({
+    diffFileTree: data,
+    folderIcon,
+    folderOpenIcon,
+    fileTreeIsVisible: false,
+    selectedItem: '',
+    fullNameMap: {},
+  });
+  fillFullNameMap(store.fullNameMap, data.TreeRoot);
+  return store;
+}
+
+function isEntryViewed(entry: DiffTreeEntry): boolean {
+  if (entry.Children) {
+    let count = 0;
+    for (const child of entry.Children) {
+      if (child.IsViewed) count++;
+    }
+    return count === entry.Children.length;
+  }
+  return entry.IsViewed;
+}