feat:优化数据

server.js

@@ -6,8 +6,9 @@ const crypto = require("crypto");
 const app = express();
 const PORT = process.env.PORT || 5180;
 const DB_PATH = path.join(__dirname, "data", "shaders.json");
+const THUMB_DIR = path.join(__dirname, "data", "thumbnails");
 
-app.use(express.json({ limit: "1mb" }));
+app.use(express.json({ limit: "4mb" }));
 app.use(express.static(__dirname));
 
 async function ensureDb() {
@@ -19,6 +20,50 @@ async function ensureDb() {
   }
 }
 
+async function ensureThumbnailsDir() {
+  await fs.mkdir(THUMB_DIR, { recursive: true });
+}
+
+function thumbPath(id) {
+  return path.join(THUMB_DIR, `${id}.png`);
+}
+
+async function thumbFileExists(id) {
+  try {
+    await fs.access(thumbPath(id));
+    return true;
+  } catch {
+    return false;
+  }
+}
+
+function decodePngBase64(s) {
+  if (!s || typeof s !== "string") return null;
+  const t = s.trim();
+  const m = /^data:image\/png;base64,(.+)$/i.exec(t);
+  const b64 = m ? m[1] : t.replace(/\s/g, "");
+  try {
+    return Buffer.from(b64, "base64");
+  } catch {
+    return null;
+  }
+}
+
+function isPngBuffer(buf) {
+  return (
+    buf &&
+    buf.length >= 8 &&
+    buf[0] === 0x89 &&
+    buf[1] === 0x50 &&
+    buf[2] === 0x4e &&
+    buf[3] === 0x47 &&
+    buf[4] === 0x0d &&
+    buf[5] === 0x0a &&
+    buf[6] === 0x1a &&
+    buf[7] === 0x0a
+  );
+}
+
 async function readDb() {
   await ensureDb();
   const raw = await fs.readFile(DB_PATH, "utf8");
@@ -286,6 +331,7 @@ async function autoNormalizeStoredShaders() {
 
 app.get("/api/shaders", async (_req, res) => {
   try {
+    await ensureThumbnailsDir();
     let shaders = await readDb();
     // Runtime safeguard: always return normalized code for display layer.
     shaders = shaders.map((item) => {
@@ -297,7 +343,16 @@ app.get("/api/shaders", async (_req, res) => {
       if (isAngleLike(raw)) next.sourceFormat = "angle-metal-auto-converted";
       return next;
     });
-    res.json(shaders);
+    const out = await Promise.all(
+      shaders.map(async (item) => {
+        const has = await thumbFileExists(item.id);
+        const thumbnailUrl = has
+          ? `/api/shaders/${encodeURIComponent(item.id)}/thumbnail`
+          : null;
+        return { ...item, thumbnailUrl };
+      })
+    );
+    res.json(out);
   } catch {
     res.status(500).json({ error: "读取失败" });
   }
@@ -333,6 +388,48 @@ app.post("/api/shaders", async (req, res) => {
   }
 });
 
+app.get("/api/shaders/:id/thumbnail", async (req, res) => {
+  try {
+    const p = thumbPath(req.params.id);
+    await fs.access(p);
+    res.setHeader("Content-Type", "image/png");
+    res.setHeader("Cache-Control", "public, max-age=86400");
+    res.sendFile(path.resolve(p));
+  } catch {
+    res.status(404).end();
+  }
+});
+
+app.post("/api/shaders/:id/thumbnail", async (req, res) => {
+  const { pngBase64 } = req.body || {};
+  const buf = decodePngBase64(pngBase64);
+  if (!buf || buf.length < 32) {
+    return res.status(400).json({ error: "无效 PNG 数据" });
+  }
+  if (!isPngBuffer(buf)) {
+    return res.status(400).json({ error: "必须是 PNG" });
+  }
+  if (buf.length > 2 * 1024 * 1024) {
+    return res.status(400).json({ error: "缩略图过大" });
+  }
+  try {
+    const shaders = await readDb();
+    const idx = shaders.findIndex((it) => it.id === req.params.id);
+    if (idx < 0) {
+      return res.status(404).json({ error: "未找到该 shader" });
+    }
+    await ensureThumbnailsDir();
+    await fs.writeFile(thumbPath(req.params.id), buf);
+    const thumbnailAt = new Date().toISOString();
+    shaders[idx] = { ...shaders[idx], thumbnailAt };
+    await writeDb(shaders);
+    const thumbnailUrl = `/api/shaders/${encodeURIComponent(req.params.id)}/thumbnail`;
+    res.json({ ok: true, thumbnailUrl, thumbnailAt });
+  } catch {
+    res.status(500).json({ error: "保存缩略图失败" });
+  }
+});
+
 app.delete("/api/shaders/:id", async (req, res) => {
   try {
     const shaders = await readDb();
@@ -341,6 +438,12 @@ app.delete("/api/shaders/:id", async (req, res) => {
       return res.status(404).json({ error: "未找到该 shader" });
     }
     await writeDb(next);
+    await ensureThumbnailsDir();
+    try {
+      await fs.unlink(thumbPath(req.params.id));
+    } catch (_) {
+      /* no thumb */
+    }
     res.status(204).end();
   } catch {
     res.status(500).json({ error: "删除失败" });