fix:新增功能并优化

stats-db.js

@@ -0,0 +1,155 @@
+const fs = require("fs/promises");
+const path = require("path");
+const initSqlJs = require("sql.js");
+
+const STATS_PATH = path.join(__dirname, "data", "stats.sqlite");
+
+let db = null;
+
+async function load() {
+  const SQL = await initSqlJs();
+  let buf;
+  try {
+    buf = await fs.readFile(STATS_PATH);
+  } catch {
+    buf = undefined;
+  }
+  db = buf ? new SQL.Database(buf) : new SQL.Database();
+  db.run(`
+    CREATE TABLE IF NOT EXISTS shader_stats (
+      id TEXT PRIMARY KEY NOT NULL,
+      views INTEGER NOT NULL DEFAULT 0,
+      likes INTEGER NOT NULL DEFAULT 0
+    );
+    CREATE TABLE IF NOT EXISTS shader_likes (
+      shader_id TEXT NOT NULL,
+      visitor_id TEXT NOT NULL,
+      PRIMARY KEY (shader_id, visitor_id)
+    );
+  `);
+}
+
+async function persist() {
+  const data = db.export();
+  await fs.writeFile(STATS_PATH, Buffer.from(data));
+}
+
+async function migrateIfEmpty(list) {
+  const r = db.exec("SELECT COUNT(*) FROM shader_stats");
+  const n = r.length && r[0].values.length ? r[0].values[0][0] : 0;
+  if (n > 0) return;
+  const stmt = db.prepare(
+    "INSERT INTO shader_stats (id, views, likes) VALUES (?, ?, ?)"
+  );
+  for (const item of list) {
+    stmt.run([
+      item.id,
+      Number(item.views) || 0,
+      Number(item.likes) || 0,
+    ]);
+  }
+  stmt.free();
+  await persist();
+}
+
+function getStatsRow(id) {
+  const stmt = db.prepare("SELECT views, likes FROM shader_stats WHERE id = ?");
+  stmt.bind([id]);
+  if (!stmt.step()) {
+    stmt.free();
+    return null;
+  }
+  const o = stmt.getAsObject();
+  stmt.free();
+  return { views: o.views, likes: o.likes };
+}
+
+function mergeItem(item, visitorId) {
+  const row = getStatsRow(item.id);
+  const views = row ? row.views : Number(item.views) || 0;
+  const likes = row ? row.likes : Number(item.likes) || 0;
+  let userLiked = false;
+  if (visitorId) {
+    const s = db.prepare(
+      "SELECT 1 FROM shader_likes WHERE shader_id = ? AND visitor_id = ?"
+    );
+    s.bind([item.id, visitorId]);
+    userLiked = s.step();
+    s.free();
+  }
+  return { ...item, views, likes, userLiked };
+}
+
+async function incrementView(id, fallback) {
+  const row = getStatsRow(id);
+  if (!row) {
+    db.run("INSERT INTO shader_stats (id, views, likes) VALUES (?, ?, ?)", [
+      id,
+      (Number(fallback.views) || 0) + 1,
+      Number(fallback.likes) || 0,
+    ]);
+  } else {
+    db.run("UPDATE shader_stats SET views = views + 1 WHERE id = ?", [id]);
+  }
+  await persist();
+  return getStatsRow(id);
+}
+
+async function tryLike(id, visitorId, fallback) {
+  const chk = db.prepare(
+    "SELECT 1 FROM shader_likes WHERE shader_id = ? AND visitor_id = ?"
+  );
+  chk.bind([id, visitorId]);
+  if (chk.step()) {
+    chk.free();
+    const r = getStatsRow(id);
+    return {
+      likes: r ? r.likes : Number(fallback.likes) || 0,
+      liked: false,
+    };
+  }
+  chk.free();
+
+  db.run("INSERT INTO shader_likes (shader_id, visitor_id) VALUES (?, ?)", [
+    id,
+    visitorId,
+  ]);
+
+  const existing = getStatsRow(id);
+  if (!existing) {
+    db.run("INSERT INTO shader_stats (id, views, likes) VALUES (?, ?, ?)", [
+      id,
+      Number(fallback.views) || 0,
+      (Number(fallback.likes) || 0) + 1,
+    ]);
+  } else {
+    db.run("UPDATE shader_stats SET likes = likes + 1 WHERE id = ?", [id]);
+  }
+  await persist();
+  return { likes: getStatsRow(id).likes, liked: true };
+}
+
+async function insertStats(id, views, likes) {
+  db.run("INSERT OR REPLACE INTO shader_stats (id, views, likes) VALUES (?, ?, ?)", [
+    id,
+    views,
+    likes,
+  ]);
+  await persist();
+}
+
+async function deleteStats(id) {
+  db.run("DELETE FROM shader_likes WHERE shader_id = ?", [id]);
+  db.run("DELETE FROM shader_stats WHERE id = ?", [id]);
+  await persist();
+}
+
+module.exports = {
+  load,
+  migrateIfEmpty,
+  mergeItem,
+  incrementView,
+  tryLike,
+  insertStats,
+  deleteStats,
+};