sunnymh-manga-site/CLAUDE.md

# CLAUDE.md

This file provides guidance to Claude Code (claude.ai/code) when working with code in this repository.

> **This is NOT the Next.js you know.** Next 16 / App Router has breaking
> changes from older training data — APIs, conventions, and file structure
> may differ. Check `node_modules/next/dist/docs/` before writing routing
> or metadata code, and heed deprecation notices.

## Build & Development Commands

```bash
npm run dev              # Start dev server (hot reload, Turbopack)
npm run build            # Production build
npm start                # Start production server
npm run lint             # ESLint (flat config, v9+)
npx prisma generate      # Regenerate Prisma client after schema changes
npx prisma db push       # Sync schema to DB (this repo uses db push, not migrate)
npx tsx scripts/backfill-page-dims.ts   # Probe Page.width/height via image-size against R2
```

The DB is managed via `prisma db push`, not `migrate dev`. `prisma/migrations/`
holds SQL files kept for reference only; `migrate dev` won't work (no shadow
DB permission on this Postgres).

## Architecture

**Stack**: Next.js 16.2.1 (App Router) · React 19 · TypeScript · Tailwind CSS v4 · Prisma · PostgreSQL 16 · Cloudflare R2

**Path alias**: `@/*` maps to project root.

### Reader is placeholder-based — read this before touching `PageReader.tsx`

`components/PageReader.tsx` is deliberately **not** a naive `pages.map(<img>)`.
Every page renders as a `<div>` placeholder with `style={{ aspectRatio: w/h }}`
so the document height is correct before any image bytes load. This avoids
a whole class of iOS Safari scroll-anchoring / prepend-shift bugs that a
simple reader would hit. Key invariants:

- `Page.width` / `Page.height` **must** be populated for every row. The
  Python scraper writes them on insert; the backfill script covers older
  rows. With dims=0, the reader falls back to 3/4 and layout shifts on
  image load.
- Initial chapter meta (dims skeleton) is fetched server-side in
  `app/manga/[slug]/[chapter]/page.tsx` and passed as a prop. Later
  chapters' meta is lazy-fetched via `/api/chapters/[id]/meta`.
- Image URLs (signed, short-TTL) come in batches via `/api/pages` triggered
  by an `IntersectionObserver` with 1200 px margin. A separate
  intersecting-pages `Map` is maintained for the scroll tick so the topmost
  visible page can be found in O(k) without walking every placeholder.
- Continuous multi-chapter reading auto-appends the next chapter when the
  user gets within `PREFETCH_NEXT_AT = 3` pages of the end.
- URL syncs to the chapter currently in viewport via
  `window.history.replaceState`. `prevChapter` / `nextChapter` for
  double-tap nav are derived from `currentChapterNum`, **not** from the URL
  or props.
- All Links into the reader use `scroll={false}`, and the double-tap
  `router.push(..., { scroll: false })`. This is load-bearing — without it,
  App Router's default scroll-to-top clobbers the `useLayoutEffect` that
  restores the resume page.
- Reading progress is persisted to `localStorage` under the key
  `sunnymh:last-read:<slug>` as JSON `{chapter, page}`. `readProgress`
  in `components/ReadingProgressButton.tsx` also accepts the **legacy
  bare-number format** (just a chapter number string) for backward
  compatibility — preserve this when touching the storage format.

### Immersive reader route

`components/Header.tsx` and `components/BottomNav.tsx` both return `null`
when the pathname matches `/manga/[slug]/[chapter]` — the reader runs
full-bleed with its own chrome. Anything new that relies on the global
nav being present needs to account for this.

### Data flow

- **Prisma models** (see `prisma/schema.prisma`): `Manga`, `Chapter`, `Page`.
  `Page` carries `width` / `height`. `Manga` has `genre` as a
  comma-separated string; parse with `lib/genres.ts`.
- **Images live in R2** (S3-compatible). Format is **WebP** (~25–35%
  smaller than JPEG). The app **never** serves R2 URLs directly —
  `lib/r2.ts::signUrl` / `signCoverUrls` mint presigned GETs with a 60 s
  TTL; `keyFromPublicUrl` reverses a public URL to its R2 key.
  `signCoverUrls` is the standardized pattern for list pages — homepage
  carousel, genre grid, search results, detail page all route through it.
  Don't bypass it by handing raw `manga.coverUrl` to the browser.
- **R2 layout** (populated by the scraper — not this app):
  - `manga/<slug>/chapters/<chapter_number>/<page_number>.webp`
  - `manga/<slug>/cover.webp`
- **Search**: PostgreSQL `contains` + `mode: 'insensitive'`. Fine up to
  ~10k titles. If a future scale requires fuzzy/full-text, the planned
  swap-in is Meilisearch.

### Key routes

- `app/page.tsx` — homepage (trending carousel + genre tabs).
- `app/manga/[slug]/page.tsx` — detail + chapter list + "continue reading".
- `app/manga/[slug]/[chapter]/page.tsx` — reader. Issues both required
  queries (manga+chapters, initial chapter page meta) in parallel via
  `Promise.all`.
- `app/api/pages/route.ts` — batched `{number, imageUrl}` with signed URLs.
- `app/api/chapters/[chapterId]/meta/route.ts` — `[{number, width, height}]`
  for lazy next-chapter prefetch.
- `app/api/search/route.ts` — case-insensitive title search.
- `app/api/upload/route.ts` — R2 presigned PUT (admin/scraper only; no DB
  write happens here).
- `app/sitemap.ts` — auto-generated `/sitemap.xml`. Each page uses
  `generateMetadata()` for per-route title/description.

### Ingestion is a sibling Python repo

New manga and chapters are created by `../manga-dl/manga.py`, not by this
web app. It scrapes, converts to WebP, uploads to R2, and writes
`Manga` / `Chapter` / `Page` rows directly via `psycopg2`. When updating the
Prisma schema, update the sibling's SQL INSERTs too (they're raw, not ORM).

### Branding

- Source SVGs in `logo/qingtian_*.svg`.
- Wired up as: `app/icon.svg` (browser favicon, Next.js convention),
  `app/apple-icon.svg` (iOS home-screen), `public/logo.svg` (Header `<img>`).
- Accent color: `#268a52` (green sunflower), defined as `--accent` in
  `app/globals.css`. Hover: `#1f7044`.
- Brand name: 晴天漫画 · Sunny MH.

### iOS Safari conventions

- `viewport` in `app/layout.tsx` sets `viewportFit: "cover"` so the app
  extends into the notch; any sticky/fixed chrome must use the
  `pt-safe` / `pb-safe` utilities from `app/globals.css` (they map to
  `env(safe-area-inset-*)`). Header and BottomNav already do.
- Horizontal carousels (`components/TrendingCarousel.tsx`) set
  `WebkitOverflowScrolling: "touch"` inline for momentum scrolling.
  Preserve this on any new swipe lane.
- `overflow-x: hidden` on `body` (globals.css) prevents the fixed
  BottomNav from leaking horizontal scroll on mobile.

## Deployment

- **Host**: Proxmox VM running Docker + Portainer.
- **Flow**: Push to Gitea (`gitea.04080616.xyz/yiekheng/sunnymh-manga-site`)
  → `git pull` on the Docker host → rebuild → restart via Portainer.
- **Dockerfile** at repo root; container listens on 3000, mapped to host
  3001. `docker-compose.yml` only brings up the app — **Postgres is
  external** (connected via `DATABASE_URL`), not defined in compose.
- **Reverse proxy**: aaPanel Nginx routes `www.04080616.xyz` →
  `http://127.0.0.1:3001`. SSL via Let's Encrypt managed in aaPanel. DDNS
  already configured — no Cloudflare Tunnel involved.
- **Host ports in use elsewhere**: 3000, 8000–8002, 8005, 2283, 5432,
  51820–51821, 9443 — don't collide. Postgres lives on host 5433.
- After schema changes reach prod, run `scripts/backfill-page-dims.ts`
  once against prod DB to populate dims for historical rows.

### Minimal Nginx location block (aaPanel)

```nginx
location / {
    proxy_pass http://127.0.0.1:3001;
    proxy_http_version 1.1;
    proxy_set_header Upgrade $http_upgrade;
    proxy_set_header Connection 'upgrade';
    proxy_set_header Host $host;
    proxy_cache_bypass $http_upgrade;
}
```

## Environment Variables

Required in `.env` (container equivalents in `docker-compose.yml`):

- `DATABASE_URL` — PostgreSQL connection string, e.g. `postgresql://manga_user:…@localhost:5433/manga_db`
- `R2_ACCOUNT_ID`, `R2_ACCESS_KEY`, `R2_SECRET_KEY`, `R2_BUCKET`, `R2_PUBLIC_URL` — Cloudflare R2

## Dev gotchas

- **`next.config.ts` has `allowedDevOrigins: ["10.8.0.2"]`** — a VPN-access
  whitelist so dev on macOS is reachable from other devices on the tunnel.
  Removing or breaking it silently blocks hot-reload from those origins;
  update it if the VPN subnet changes.
- **`prisma/seed.ts` is documentation-only.** The real data pipeline is
  the sibling Python scraper (`../manga-dl/manga.py`) writing directly via
  `psycopg2`. The `npm run seed` script exists for quick local dev but is
  never run in production.