Add auto-hide nav bars on scroll and chapter selector bottom sheet

Nav bars hide when scrolling down and reappear on scroll up.
Replace static page count with a chapter picker that opens as a
bottom sheet drawer for quick chapter navigation.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

app/manga/[slug]/[chapter]/page.tsx

@@ -53,6 +53,11 @@ export default async function ChapterReaderPage({ params }: Props) {
       ? manga.chapters[chapterIndex + 1].number
       : null;
 
+  const allChapters = manga.chapters.map((c) => ({
+    number: c.number,
+    title: c.title,
+  }));
+
   return (
     <PageReader
       pages={currentChapter.pages}
@@ -62,6 +67,7 @@ export default async function ChapterReaderPage({ params }: Props) {
       chapterTitle={currentChapter.title}
       prevChapter={prevChapter}
       nextChapter={nextChapter}
+      chapters={allChapters}
     />
   );
 }

components/PageReader.tsx

@@ -1,6 +1,6 @@
 "use client";
 
-import { useState } from "react";
+import { useState, useEffect, useRef } from "react";
 import Link from "next/link";
 
 type PageData = {
@@ -8,6 +8,11 @@ type PageData = {
   imageUrl: string;
 };
 
+type ChapterInfo = {
+  number: number;
+  title: string;
+};
+
 type PageReaderProps = {
   pages: PageData[];
   mangaSlug: string;
@@ -16,6 +21,7 @@ type PageReaderProps = {
   chapterTitle: string;
   prevChapter: number | null;
   nextChapter: number | null;
+  chapters: ChapterInfo[];
 };
 
 export function PageReader({
@@ -26,8 +32,26 @@ export function PageReader({
   chapterTitle,
   prevChapter,
   nextChapter,
+  chapters,
 }: PageReaderProps) {
   const [showUI, setShowUI] = useState(true);
+  const [showDrawer, setShowDrawer] = useState(false);
+  const lastScrollY = useRef(0);
+
+  useEffect(() => {
+    const handleScroll = () => {
+      const currentY = window.scrollY;
+      if (currentY > lastScrollY.current && currentY > 50) {
+        setShowUI(false);
+      } else if (currentY < lastScrollY.current) {
+        setShowUI(true);
+      }
+      lastScrollY.current = currentY;
+    };
+
+    window.addEventListener("scroll", handleScroll, { passive: true });
+    return () => window.removeEventListener("scroll", handleScroll);
+  }, []);
 
   return (
     <div className="min-h-screen bg-black relative">
@@ -106,9 +130,23 @@ export function PageReader({
           ) : (
             <div />
           )}
-          <span className="text-white/50 text-xs">
-            {pages.length} pages
-          </span>
+          <button
+            onClick={() => setShowDrawer(true)}
+            className="flex items-center gap-1 text-white/80 hover:text-white text-sm transition-colors"
+          >
+            <svg
+              viewBox="0 0 24 24"
+              fill="none"
+              stroke="currentColor"
+              strokeWidth={2}
+              className="w-5 h-5"
+            >
+              <line x1="3" y1="6" x2="21" y2="6" />
+              <line x1="3" y1="12" x2="21" y2="12" />
+              <line x1="3" y1="18" x2="21" y2="18" />
+            </svg>
+            Ch. {chapterNumber}
+          </button>
           {nextChapter ? (
             <Link
               href={`/manga/${mangaSlug}/${nextChapter}`}
@@ -135,6 +173,49 @@ export function PageReader({
           )}
         </div>
       </div>
+      {/* Chapter drawer overlay */}
+      {showDrawer && (
+        <div
+          className="fixed inset-0 z-[60]"
+          onClick={() => setShowDrawer(false)}
+        >
+          {/* Backdrop */}
+          <div className="absolute inset-0 bg-black/60" />
+
+          {/* Bottom sheet */}
+          <div
+            className="absolute bottom-0 left-0 right-0 max-h-[60vh] bg-zinc-900 rounded-t-2xl overflow-hidden"
+            onClick={(e) => e.stopPropagation()}
+          >
+            {/* Handle + header */}
+            <div className="sticky top-0 bg-zinc-900 z-10">
+              <div className="flex justify-center pt-2 pb-1">
+                <div className="w-10 h-1 rounded-full bg-white/20" />
+              </div>
+              <div className="px-4 pb-2 border-b border-white/10">
+                <span className="text-white text-sm font-medium">Chapters</span>
+              </div>
+            </div>
+            {/* Chapter list */}
+            <div className="overflow-y-auto max-h-[calc(60vh-3rem)] pb-safe">
+              {chapters.map((ch) => (
+                <Link
+                  key={ch.number}
+                  href={`/manga/${mangaSlug}/${ch.number}`}
+                  className={`block px-4 py-3 text-sm transition-colors ${
+                    ch.number === chapterNumber
+                      ? "bg-white/10 text-white font-medium"
+                      : "text-white/70 hover:bg-white/5 hover:text-white"
+                  }`}
+                  onClick={() => setShowDrawer(false)}
+                >
+                  Ch. {ch.number} — {ch.title}
+                </Link>
+              ))}
+            </div>
+          </div>
+        </div>
+      )}
     </div>
   );
 }