feat: implement content reveal mechanism via DOM traversal

Add `addRevealedClasses` to apply `revealed` or `concealed` CSS classes
to article elements based on the current heading hierarchy and
revealed paths. Update `Article` to expose its DOM element via an
`onDom` callback.

src/App.tsx

@@ -1,6 +1,9 @@
 import { Component, createEffect, createMemo, createSignal } from "solid-js";
 import { useLocation } from "@solidjs/router";
-import { useJournalStream } from "./components/stores/journalStream";
+import {
+  addRevealedClasses,
+  useJournalStream,
+} from "./components/stores/journalStream";
 
 // 导入组件以注册自定义元素
 import "./components";
@@ -123,6 +126,9 @@ const App: Component = () => {
           <Article
             class="prose text-black prose-sm max-w-full flex-1"
             src={currentPath()}
+            onDom={(dom) =>
+              addRevealedClasses(dom, stream.revealedPaths[currentPath()])
+            }
           />
         </main>
       </div>

src/components/Article.tsx

@@ -21,6 +21,7 @@ export interface ArticleProps {
   onError?: (error: Error) => void;
   class?: string; // 额外的 class 用于样式控制
   scrollToHash?: boolean; // 是否自动滚动到 hash
+  onDom?: (dom: HTMLDivElement) => void;
 }
 
 async function fetchArticleContent(params: {
@@ -64,6 +65,7 @@ export const Article: Component<ArticleProps> = (props) => {
     () => ({ src: props.src, section: props.section }),
     fetchArticleContent,
   );
+  let innerDiv!: HTMLDivElement;
 
   // 解析 iconPath，默认为 "./assets"，空字符串表示禁用
   const iconPrefix = createMemo(() => {
@@ -80,6 +82,8 @@ export const Article: Component<ArticleProps> = (props) => {
 
       // 内容渲染后检查 hash 并滚动
       scrollToHash(location.hash);
+
+      props.onDom?.(innerDiv);
     }
   });
 
@@ -101,6 +105,7 @@ export const Article: Component<ArticleProps> = (props) => {
       <Show when={!content.loading && !content.error && content()}>
         <div
           class="relative"
+          ref={innerDiv}
           innerHTML={parseMarkdown(content()!, iconPrefix())}
         />
       </Show>

src/components/Sidebar.tsx

@@ -3,6 +3,7 @@ import { generateToc, type FileNode, type TocNode } from "../data-loader";
 import { useLocation } from "@solidjs/router";
 import { FileTreeNode, HeadingNode } from "./FileTree";
 import { isPathRevealed } from "./stores/journalStream";
+import { createEffect } from "solid-js";
 
 export interface SidebarProps {
   isOpen: boolean;
@@ -43,8 +44,8 @@ const SidebarContent: Component<SidebarContentProps> = (props) => {
     }
     for (const node of currentFileHeadings()) {
       traverse(node, (anode) => {
-        if (isPathRevealed(pathname, anode.title)) {
-          traverse(anode, (each) => set.add(each.title));
+        if (isPathRevealed(pathname, anode.id ?? anode.title)) {
+          traverse(anode, (each) => set.add(anode.id ?? anode.title));
         }
       });
     }
@@ -56,10 +57,13 @@ const SidebarContent: Component<SidebarContentProps> = (props) => {
     return true;
   };
   const isHeadingHidden = (node: TocNode): boolean => {
-    if (revealedHeadings().has(node.title)) return false;
+    if (revealedHeadings().has(node.id ?? node.title)) return false;
     if (node.children?.some((child) => !isHeadingHidden(child))) return false;
     return true;
   };
+  createEffect(() => {
+    console.log(currentFileHeadings(), revealedHeadings());
+  });
 
   return (
     <div class="flex flex-col h-full">

src/components/stores/journalStream.ts

@@ -627,6 +627,54 @@ export function isPathRevealed(path: string, section?: string): boolean {
   return revealed.size > 0;
 }
 
+/**
+ * Walk every element in `root` and tag it as revealed or concealed.
+ *
+ * Headings (h1–h6) update a current-heading tracker. When a higher-level
+ * heading is encountered (e.g. h2 after h1), all sub-headings at deeper
+ * levels are cleared. Each non-heading element receives a `revealed` or
+ * `concealed` CSS class depending on whether any of its current heading
+ * ancestors is present in the `revealed` set.
+ */
+export function addRevealedClasses(
+  root: HTMLDivElement,
+  revealed: Set<string>,
+) {
+  if (!revealed) return;
+  // Current heading text for each level (h1..h6, index 1..6)
+  const cur: Record<number, string> = {};
+
+  const HEADING_TAGS = new Set(["H1", "H2", "H3", "H4", "H5", "H6"]);
+
+  const walk = (el: Element) => {
+    const tag = el.tagName.toUpperCase();
+
+    if (HEADING_TAGS.has(tag)) {
+      const level = Number(tag.charAt(1)); // 1-6
+      const text = el.textContent?.trim() ?? "";
+
+      // Update current heading at this level
+      cur[level] = text;
+      // Clear all deeper heading levels
+      for (let l = level + 1; l <= 6; l++) delete cur[l];
+    } else {
+      // Non-heading: check if any current heading ancestor is revealed
+      const isRevealed = Object.values(cur).some((h) => revealed.has(h));
+      el.classList.add(isRevealed ? "revealed" : "concealed");
+    }
+
+    // Recurse into children
+    for (const child of el.children) {
+      walk(child);
+    }
+  };
+
+  // Start walk from root's children (skip the container itself)
+  for (const child of root.children) {
+    walk(child);
+  }
+}
+
 /** Normalize a path for lookup: strip .md, leading ./ or / */
 function normalizePath(p: string): string {
   return p.replace(/^\.?\//, "").replace(/\.md$/, "");