feat: complete v0.3 reading and discovery experience

app/api/reactions/route.ts

@@ -1,2 +1,19 @@
-import { NextResponse } from "next/server"; import { requireUser } from "@/lib/auth"; import { db } from "@/lib/db"; import { externalUrl } from "@/lib/http";
-const allowed=new Set(['👍','❤️','🎉','🤔']);export async function POST(req:Request){try{const user=await requireUser();const f=await req.formData();const postId=Number(f.get('postId'));const emoji=String(f.get('emoji'));if(!postId||!allowed.has(emoji))throw 0;const found=db.prepare('SELECT 1 FROM reactions WHERE post_id=? AND user_id=? AND emoji=?').get(postId,user.id,emoji);if(found)db.prepare('DELETE FROM reactions WHERE post_id=? AND user_id=? AND emoji=?').run(postId,user.id,emoji);else db.prepare('INSERT INTO reactions(post_id,user_id,emoji) VALUES(?,?,?)').run(postId,user.id,emoji);return NextResponse.redirect(externalUrl(req,`/posts/${postId}`));}catch{return NextResponse.redirect(externalUrl(req,'/'));}}
+import { NextResponse } from "next/server";
+import { requireUser } from "@/lib/auth";
+import { db } from "@/lib/db";
+import { externalUrl } from "@/lib/http";
+import { notify } from "@/lib/notifications";
+
+const allowed = new Set(["👍", "❤️", "🎉", "🤔"]);
+export async function POST(req: Request) {
+  try {
+    const user = await requireUser(); const form = await req.formData(); const postId = Number(form.get("postId")); const emoji = String(form.get("emoji"));
+    if (!postId || !allowed.has(emoji)) throw new Error("Invalid reaction");
+    const post = db.prepare("SELECT author_id FROM posts WHERE id=? AND hidden=0").get(postId) as { author_id: number } | undefined;
+    if (!post) throw new Error("Post not found");
+    const found = db.prepare("SELECT 1 FROM reactions WHERE post_id=? AND user_id=? AND emoji=?").get(postId, user.id, emoji);
+    if (found) db.prepare("DELETE FROM reactions WHERE post_id=? AND user_id=? AND emoji=?").run(postId, user.id, emoji);
+    else { db.prepare("INSERT INTO reactions(post_id,user_id,emoji) VALUES(?,?,?)").run(postId, user.id, emoji); notify(post.author_id, user.id, postId, "reaction", `@${user.username} 對你的貼文給了 ${emoji}`); }
+    return NextResponse.redirect(externalUrl(req, `/posts/${postId}`));
+  } catch { return NextResponse.redirect(externalUrl(req, "/")); }
+}