TOCコンポーネントを追加し、見出しに自動IDを付与する機能を実装しました。また、スタイルを改善しました。

next/package.json

@@ -93,6 +93,7 @@
 		"sonner": "2.0.1",
 		"tailwind-merge": "3.0.1",
 		"tailwindcss-animate": "1.0.7",
+		"tocbot": "4.35.0",
 		"tsx": "4.19.3",
 		"unified": "11.0.5",
 		"unist-util-visit": "5.0.0",

next/src/app/[locale]/(common-layout)/user/[handle]/page/[slug]/components/floating-controls.tsx

@@ -2,10 +2,12 @@
 import { LikeButton } from "@/app/[locale]/components/like-button/client";
 import { Button } from "@/components/ui/button";
 import { cn } from "@/lib/utils";
-import { Languages, Text } from "lucide-react";
+import { Languages, Text } from "lucide-react"; // List アイコンをインポート
 import { useQueryState } from "nuqs";
 import { useCallback, useEffect, useRef, useState } from "react";
 import { ShareDialog } from "./share-dialog";
+import Toc from "./toc";
+
 interface FloatingControlsProps {
 	liked: boolean;
 	likeCount: number;
@@ -36,91 +38,110 @@ export function FloatingControls({
 			shallow: true,
 		},
 	);
-
 	const [isVisible, setIsVisible] = useState(true);
 	const [lastScrollY, setLastScrollY] = useState(0);
-
 	const ignoreScrollRef = useRef(false);
 
-	const handleScroll = useCallback(() => {
+	const handleShowFloatingControls = useCallback(() => {
 		if (ignoreScrollRef.current) return;
 
 		const currentScrollY = window.scrollY;
+		const viewportHeight = window.innerHeight;
+
+		// スクロール量をビューポートの高さに対する割合で計算
 		const scrollDelta = currentScrollY - lastScrollY;
 
-		if (scrollDelta > 100) {
+		// スクロール方向を検出
+		if (scrollDelta > 0) {
+			// 下方向へのスクロール - コントロールを非表示
 			setIsVisible(false);
-		} else if (scrollDelta < 0 || currentScrollY < 100) {
+		} else {
+			// 上方向へのスクロール - コントロールを表示
+			setIsVisible(true);
+		}
+
+		// ページ最上部付近（ビューポートの3%以内）では常に表示
+		if (currentScrollY < viewportHeight * 0.03) {
 			setIsVisible(true);
 		}
 
 		setLastScrollY(currentScrollY);
 	}, [lastScrollY]);
 
 	useEffect(() => {
-		window.addEventListener("scroll", handleScroll, { passive: true });
+		window.addEventListener("scroll", handleShowFloatingControls, {
+			passive: true,
+		});
 		return () => {
-			window.removeEventListener("scroll", handleScroll);
+			window.removeEventListener("scroll", handleShowFloatingControls);
 		};
-	}, [handleScroll]);
+	}, [handleShowFloatingControls]);
 
 	const baseClasses =
 		"drop-shadow-xl dark:drop-shadow-[0_9px_7px_rgba(255,255,255,0.1)] h-12 w-12 rounded-full";
 	const baseButtonClasses = `${baseClasses} border relative bg-background`;
 	/** 非選択状態（トグルOFF）時の追加クラス */
 	const toggledOffClasses = `bg-muted after:absolute after:w-full after:h-[1px] after:bg-current after:top-1/2 
 		after:left-0 after:origin-center after:-rotate-45`;
-	/** アイコンラッパーのクラス */
 
 	return (
 		<div
 			className={cn(
-				"fixed bottom-4 right-4 lg:right-8 xl:right-[15%] 2xl:right-[20%] flex gap-3 transition-all duration-300 transform",
+				"fixed bottom-4 right-4 lg:right-8 xl:right-[15%] 2xl:right-[20%] transition-all duration-300 transform",
 				isVisible ? "translate-y-0 opacity-100" : "translate-y-20 opacity-0",
 			)}
 		>
-			<Button
-				variant="ghost"
-				size="icon"
-				className={cn(baseButtonClasses, !showOriginal && toggledOffClasses)}
-				onClick={() => {
-					setShowOriginal(!showOriginal);
-					ignoreScrollRef.current = true;
-					setTimeout(() => {
-						ignoreScrollRef.current = false;
-					}, 100);
-				}}
-				title={showOriginal ? "Hide original text" : "Show original text"}
-			>
-				<Text
-					className={cn("h-5 w-5 opacity-100", !showOriginal && "opacity-50")}
-				/>
-			</Button>
-			<Button
-				variant="ghost"
-				size="icon"
-				className={cn(baseButtonClasses, !showTranslation && toggledOffClasses)}
-				onClick={() => {
-					setShowTranslation(!showTranslation);
-					ignoreScrollRef.current = true;
-					setTimeout(() => {
-						ignoreScrollRef.current = false;
-					}, 100);
-				}}
-				title={showTranslation ? "Hide translation" : "Show translation"}
-			>
-				<Languages
+			<div className=" bg-background mb-3 p-4 rounded-xl drop-shadow-xl dark:drop-shadow-[0_9px_7px_rgba(255,255,255,0.1)] border border-border">
+				<Toc />
+			</div>
+			<div className="flex gap-3">
+				<Button
+					variant="ghost"
+					size="icon"
+					className={cn(baseButtonClasses, !showOriginal && toggledOffClasses)}
+					onClick={() => {
+						setShowOriginal(!showOriginal);
+						ignoreScrollRef.current = true;
+						setTimeout(() => {
+							ignoreScrollRef.current = false;
+						}, 100);
+					}}
+					title={showOriginal ? "Hide original text" : "Show original text"}
+				>
+					<Text
+						className={cn("h-5 w-5 opacity-100", !showOriginal && "opacity-50")}
+					/>
+				</Button>
+				<Button
+					variant="ghost"
+					size="icon"
 					className={cn(
-						"h-5 w-5 opacity-100",
-						!showTranslation && "opacity-50",
+						baseButtonClasses,
+						!showTranslation && toggledOffClasses,
 					)}
-				/>
-			</Button>
-			<div className={baseClasses}>
-				<LikeButton liked={liked} likeCount={likeCount} slug={slug} />
-			</div>
-			<div className={baseClasses}>
-				<ShareDialog title={shareTitle} firstImageUrl={firstImageUrl} />
+					onClick={() => {
+						setShowTranslation(!showTranslation);
+						ignoreScrollRef.current = true;
+						setTimeout(() => {
+							ignoreScrollRef.current = false;
+						}, 100);
+					}}
+					title={showTranslation ? "Hide translation" : "Show translation"}
+				>
+					<Languages
+						className={cn(
+							"h-5 w-5 opacity-100",
+							!showTranslation && "opacity-50",
+						)}
+					/>
+				</Button>
+
+				<div className={baseClasses}>
+					<LikeButton liked={liked} likeCount={likeCount} slug={slug} />
+				</div>
+				<div className={baseClasses}>
+					<ShareDialog title={shareTitle} firstImageUrl={firstImageUrl} />
+				</div>
 			</div>
 		</div>
 	);

next/src/app/[locale]/(common-layout)/user/[handle]/page/[slug]/components/parsed-content.tsx

@@ -9,6 +9,7 @@ import parse, {
 	type DOMNode,
 } from "html-react-parser";
 import DOMPurify from "isomorphic-dompurify";
+import { customAlphabet } from "nanoid";
 import Image from "next/image";
 import { memo } from "react";
 import { SegmentAndTranslationSection } from "./segment-and-translation-section";
@@ -33,6 +34,15 @@ export function ParsedContent({
 
 	const options: HTMLReactParserOptions = {
 		replace: (domNode) => {
+			if (domNode.type === "tag" && /^h[1-6]$/.test(domNode.name)) {
+				// 既に id が存在するかチェック
+				if (!domNode.attribs.id) {
+					const ALPHABET =
+						"ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz";
+					const uuid = customAlphabet(ALPHABET, 8)();
+					domNode.attribs.id = uuid;
+				}
+			}
 			if (domNode.type === "tag" && domNode.attribs["data-number-id"]) {
 				const number = Number(domNode.attribs["data-number-id"]);
 				const segmentWithTranslation = segmentWithTranslations?.find(
@@ -73,6 +83,5 @@ export function ParsedContent({
 			return domNode;
 		},
 	};
-
-	return parse(sanitizedContent, options);
+	return <span className="js-content">{parse(sanitizedContent, options)}</span>;
 }

next/src/app/[locale]/(common-layout)/user/[handle]/page/[slug]/components/toc.tsx

@@ -0,0 +1,27 @@
+"use client";
+import { useEffect } from "react";
+import * as tocbot from "tocbot";
+import "tocbot/dist/tocbot.css";
+
+export default function PostContent() {
+	useEffect(() => {
+		// tocbotの初期化
+		tocbot.init({
+			tocSelector: ".js-toc",
+			contentSelector: ".js-content",
+			headingSelector: "h1, h2, h3",
+			collapseDepth: 10,
+			orderedList: false,
+			headingLabelCallback: (text) => {
+				// 10文字以上の場合は10文字に切り詰めて「...」を追加
+				return text.length > 10 ? `${text.substring(0, 10)}...` : text;
+			},
+		});
+
+		// コンポーネントのアンマウント時にリソースを解放
+		return () => {
+			tocbot.destroy();
+		};
+	}, []);
+	return <nav className="js-toc" />;
+}

next/src/app/[locale]/components/header/base-header-layout.tsx

@@ -49,7 +49,7 @@ export function BaseHeaderLayout({
 					<div className="flex items-center gap-4">
 						{rightExtra}
 						{showUserMenu && currentUser && (
-							<DropdownMenu>
+							<DropdownMenu modal={false}>
 								<DropdownMenuTrigger>
 									<Avatar className="w-6 h-6">
 										<AvatarImage

next/src/app/globals.css

@@ -100,3 +100,20 @@
 body.virtual-keyboard-shown {
 	margin-top: var(--visual-viewport-offset-top, 0px);
 }
+
+.toc-link:before {
+	@apply !hidden;
+}
+
+.toc-list {
+	@apply text-slate-400 !list-none;
+}
+.toc-link {
+	@apply !no-underline;
+}
+.toc-link:hover {
+	@apply !underline;
+}
+.is-active-link {
+	@apply !text-primary;
+}