feat(plugin-notes-data): add auto sidebar option

packages/plugin-notes-data/src/node/prepareNotesData.ts

@@ -95,10 +95,47 @@ export const watchNotesData = (
 
 function initSidebar(note: NotesItem, pages: NotePage[]): NotesSidebarItem[] {
   if (!note.sidebar) return []
-  if (note.sidebar === 'auto') return []
+  if (note.sidebar === 'auto') return initSidebarByAuto(note, pages)
   return initSidebarByConfig(note, pages)
 }
 
+function initSidebarByAuto(
+  note: NotesItem,
+  pages: NotePage[]
+): NotesSidebarItem[] {
+  pages = pages.sort((prev, next) => {
+    const pi = prev.relativePath.match(/\//g)?.length || 0
+    const ni = next.relativePath.match(/\//g)?.length || 0
+    return pi < ni ? -1 : 1
+  })
+  const RE_INDEX = ['index.md', 'README.md', 'readme.md']
+  const result: NotesSidebarItem[] = []
+  for (const page of pages) {
+    const { relativePath, title, link } = page
+    const paths = relativePath
+      .slice(note.dir.replace(/^\/|\/$/g, '').length + 1)
+      .split('/')
+    let index = 0
+    let dir: string
+    let items = result
+    while ((dir = paths[index])) {
+      const text = dir.replace(/\.md$/, '')
+      let current = items.find((item) => item.text === text)
+      if (!current) {
+        current = { text, link: undefined, items: [] }
+        !RE_INDEX.includes(dir) ? items.push(current) : items.unshift(current)
+      }
+      if (dir.endsWith('.md')) {
+        current.link = link
+        current.text = title
+      }
+      items = current.items as NotesSidebarItem[]
+      index++
+    }
+  }
+  return result
+}
+
 function initSidebarByConfig(
   { text, dir, sidebar }: NotesItem,
   pages: NotePage[]
@@ -116,6 +153,7 @@ function initSidebarByConfig(
       return {
         text: item.text || item.dir || current?.title,
         collapsed: item.collapsed,
+        link: item.link,
         items: initSidebarByConfig(
           {
             link: item.link || '',