From dd19497426b24f05f157187a00a8d488d6566938 Mon Sep 17 00:00:00 2001
From: Joscha <joscha@plugh.de>
Date: Fri, 7 Feb 2025 02:14:09 +0100
Subject: [PATCH] Store paths of unfolded nodes in ui state

---
 gdn-app/src/App.vue                     |  8 ++--
 gdn-app/src/components/CNavbar.vue      |  6 +--
 gdn-app/src/components/CNote.vue        | 55 ++++++++-----------------
 gdn-app/src/components/CNoteCreator.vue |  2 +-
 gdn-app/src/stores/ui.ts                | 28 +++++++++++--
 gdn-app/src/util.ts                     | 25 +++++++++++
 gdn-app/tsconfig.json                   |  4 +-
 7 files changed, 77 insertions(+), 51 deletions(-)
 create mode 100644 gdn-app/src/util.ts

diff --git a/gdn-app/src/App.vue b/gdn-app/src/App.vue
index f2590b5..a82cfac 100644
--- a/gdn-app/src/App.vue
+++ b/gdn-app/src/App.vue
@@ -11,10 +11,10 @@ const ui = useUiStore();
     <CNavbar />
     <div class="h-full overflow-auto p-1">
       <CNote
-        v-if="ui.anchor"
-        :noteId="ui.anchor"
-        :path="[]"
-        :focusPath="ui.focusPath"
+        v-if="ui.anchorId"
+        :noteId="ui.anchorId"
+        :path="''"
+        :forceOpen="true"
       />
     </div>
   </div>
diff --git a/gdn-app/src/components/CNavbar.vue b/gdn-app/src/components/CNavbar.vue
index 1339093..fc6d328 100644
--- a/gdn-app/src/components/CNavbar.vue
+++ b/gdn-app/src/components/CNavbar.vue
@@ -1,10 +1,10 @@
 <script setup lang="ts">
+import { Note, useNotesStore } from "@/stores/notes";
 import { useReposStore } from "@/stores/repos";
+import { useUiStore } from "@/stores/ui";
 import { RiDeleteBinFill, RiNodeTree, RiSettings3Fill } from "@remixicon/vue";
 import CNavbarButton from "./CNavbarButton.vue";
 import CNavbarDropdown from "./CNavbarDropdown.vue";
-import { useUiStore } from "@/stores/ui";
-import { Note, useNotesStore } from "@/stores/notes";
 
 const repos = useReposStore();
 const notes = useNotesStore();
@@ -29,7 +29,7 @@ function createSomeNotes() {
 
   const root = mkNote("root", n1.id, n2.id, n3.id, n4.id, n5.id, n2.id);
 
-  ui.anchor = root.id;
+  ui.anchorId = root.id;
 
   // Shuffle children of root
   root.children = root.children
diff --git a/gdn-app/src/components/CNote.vue b/gdn-app/src/components/CNote.vue
index b84e1d7..4ed2cef 100644
--- a/gdn-app/src/components/CNote.vue
+++ b/gdn-app/src/components/CNote.vue
@@ -1,6 +1,7 @@
 <script setup lang="ts">
 import { useNotesStore } from "@/stores/notes";
 import { useUiStore } from "@/stores/ui";
+import { pathAppend } from "@/util";
 import {
   RiArrowDownSLine,
   RiArrowRightSLine,
@@ -15,8 +16,8 @@ const ui = useUiStore();
 
 const props = defineProps<{
   noteId: string;
-  path: number[]; // From root to here
-  focusPath?: number[]; // From here to focus
+  path: string; // From root to here
+  forceOpen?: boolean;
 }>();
 
 const note = computed(() => notes.notes.get(props.noteId));
@@ -35,53 +36,34 @@ const children = computed(() => {
   return children;
 });
 
-const open = ref(false);
-
-const focused = computed(() => props.focusPath?.length === 0);
-
+const open = computed(() => ui.openPaths.has(props.path));
+const focused = computed(() => ui.focusPath === props.path);
 const creating = ref(false);
 
-// We want to set open to true when we're on the focus path, but then it should
-// stay true. Hence a computed() combining open and forceOpen would not suffice.
+// Ensure we're open if we need to be.
 watchEffect(() => {
-  open.value; // Ensure we stay open if `open.value = false` is attempted
-  if (props.focusPath && props.focusPath.length > 0) open.value = true;
+  if (props.forceOpen || creating.value) {
+    if (!ui.openPaths.has(props.path)) {
+      ui.openPaths.add(props.path);
+    }
+  }
 });
 
-// Abort creating a child node whenever we stop being focused.
+// Abort creating whenever we stop being focused.
 watchEffect(() => {
   if (!focused.value) creating.value = false;
 });
 
-// Ensure the creator component is visible.
-watchEffect(() => {
-  if (creating.value) open.value = true;
-});
-
-function focusPathFor(index: number): number[] | undefined {
-  if (!props.focusPath) return undefined;
-  if (index !== props.focusPath[0]) return undefined;
-  return props.focusPath.slice(1);
-}
-
 function focusOnThis() {
-  ui.focusPath = props.path.slice();
+  ui.focusPath = props.path;
 }
 
 function toggleOpen() {
-  if (props.focusPath) {
-    // We're on the focus path, so the situation is one of these cases:
-    //
-    // 1. We're closed and focused, in which case this does nothing.
-    // 2. We're open and focused, in which case this does nothing.
-    // 3. We're open and on the focus path, in which case closing will hide the
-    //    actual focus and we should be focused instead.
-    //
-    // In any case, we can just...
-    focusOnThis();
+  if (open.value) {
+    ui.openPaths.delete(props.path);
+  } else {
+    ui.openPaths.add(props.path);
   }
-
-  open.value = !open.value;
 }
 
 function onClick() {
@@ -125,8 +107,7 @@ function onClick() {
         v-for="([noteId, key], index) in children"
         :key
         :note-id
-        :path="path.concat(index)"
-        :focusPath="focusPathFor(index)"
+        :path="pathAppend(path, index)"
       />
     </div>
 
diff --git a/gdn-app/src/components/CNoteCreator.vue b/gdn-app/src/components/CNoteCreator.vue
index 3acb4b2..135c06d 100644
--- a/gdn-app/src/components/CNoteCreator.vue
+++ b/gdn-app/src/components/CNoteCreator.vue
@@ -1,7 +1,7 @@
 <script setup lang="ts">
 import { RiAddLine, RiCheckLine, RiCloseLine } from "@remixicon/vue";
-import CNoteButton from "./CNoteButton.vue";
 import { onMounted, ref, useTemplateRef } from "vue";
+import CNoteButton from "./CNoteButton.vue";
 
 const emit = defineEmits<{
   (e: "close"): void;
diff --git a/gdn-app/src/stores/ui.ts b/gdn-app/src/stores/ui.ts
index 68a1cc4..5f961dd 100644
--- a/gdn-app/src/stores/ui.ts
+++ b/gdn-app/src/stores/ui.ts
@@ -1,12 +1,32 @@
+import { pathAncestors, pathLiesOn } from "@/util";
 import { defineStore } from "pinia";
-import { ref } from "vue";
+import { ref, watch, watchEffect } from "vue";
 
 export const useUiStore = defineStore("ui", () => {
-  const anchor = ref<string>();
-  const focusPath = ref<number[]>([1]);
+  const anchorId = ref<string>();
+  const focusPath = ref<string>("");
+  const openPaths = ref<Set<string>>(new Set());
+
+  // Ensure all nodes on the focusPath are unfolded.
+  watchEffect(() => {
+    // The node pointed to by the path itself doesn't need to be unfolded.
+    for (const ancestor of pathAncestors(focusPath.value).slice(1)) {
+      openPaths.value.add(ancestor);
+    }
+  });
+
+  // Ensure the focusPath is updated when a node that lies on it is folded.
+  watch(openPaths, (now, old) => {
+    for (const folded of old.difference(now)) {
+      if (pathLiesOn(folded, focusPath.value)) {
+        focusPath.value = folded;
+      }
+    }
+  });
 
   return {
-    anchor,
+    anchorId,
     focusPath,
+    openPaths,
   };
 });
diff --git a/gdn-app/src/util.ts b/gdn-app/src/util.ts
new file mode 100644
index 0000000..e0c5c27
--- /dev/null
+++ b/gdn-app/src/util.ts
@@ -0,0 +1,25 @@
+function pathString(path: number[]): string {
+  return path.join("/");
+}
+
+function pathParse(path: string): number[] {
+  if (path === "") return [];
+  return path.split("/").map((it) => Number.parseInt(it));
+}
+
+export function pathAppend(path: string, segment: number): string {
+  return pathString(pathParse(path).concat(segment));
+}
+
+export function pathAncestors(path: string): string[] {
+  const parsedPath = pathParse(path);
+  const result = [];
+  for (let i = parsedPath.length; i >= 0; i--) {
+    result.push(pathString(parsedPath.slice(0, i)));
+  }
+  return result;
+}
+
+export function pathLiesOn(p1: string, p2: string): boolean {
+  return pathAncestors(p2).indexOf(p1) >= 0;
+}
diff --git a/gdn-app/tsconfig.json b/gdn-app/tsconfig.json
index d5f5a21..c1ccdf0 100644
--- a/gdn-app/tsconfig.json
+++ b/gdn-app/tsconfig.json
@@ -26,8 +26,8 @@
 
     // Language and Environment
     "jsx": "preserve",
-    "lib": ["ES2020", "DOM", "DOM.Iterable"],
-    "target": "ES2020",
+    "lib": ["ESNext", "DOM", "DOM.Iterable"],
+    "target": "ESNext",
     "useDefineForClassFields": true,
 
     // Completeness