"use client";

/**
 * /u/me/hidden — the owner's hidden posts.
 *
 * Posts hidden from timelines + public collections live here (and in any
 * private collections). Each card's overflow menu offers "Unhide from
 * timeline"; on unhide we drop the post from this list since it's no longer
 * hidden. The tab itself is only shown (by the /u/me layout) when the user
 * has at least one hidden post.
 */

import { useEffect, useState } from "react";
import { useRouter } from "next/navigation";
import { useAuth } from "@/components/auth/auth-provider";
import { PostScrollCard } from "@/components/social/post/post-scroll-card";
import { posts, SocialError, type Post } from "@/lib/social";

export default function MyHiddenPostsPage() {
  const { user } = useAuth();
  const router = useRouter();
  const [feed, setFeed] = useState<Post[]>([]);
  const [loading, setLoading] = useState(true);
  const [error, setError] = useState<string | null>(null);

  useEffect(() => {
    if (!user) return;
    posts
      .hidden()
      .then((rows) => {
        const list = rows ?? [];
        setFeed(list);
        // Nothing hidden → the "Hidden" tab isn't in the strip, so this page
        // is a tab-less dead-end. Send the user to their Posts tab instead.
        if (list.length === 0) router.replace("/u/me");
      })
      .catch((err) =>
        setError(
          err instanceof SocialError
            ? err.message
            : "Could not load hidden posts.",
        ),
      )
      .finally(() => setLoading(false));
  }, [user, router]);

  function onPostUpdated(updated: Post) {
    setFeed((rows) => rows.map((p) => (p.id === updated.id ? updated : p)));
  }

  // Unhiding a post means it's no longer hidden → drop it from this list.
  // When that empties the list, the "Hidden" tab disappears (the layout's
  // count hits 0), so move the user to their Posts tab rather than leaving
  // them on an empty page with no active tab.
  function onHiddenChange(id: string, hidden: boolean) {
    if (hidden) return;
    const remaining = feed.filter((p) => p.id !== id);
    setFeed(remaining);
    if (remaining.length === 0) router.replace("/u/me");
  }

  if (!user) return null;

  return (
    <div className="max-w-xl w-full mx-auto space-y-6">
      <p className="text-sm text-muted-foreground">
        Hidden posts don&apos;t appear on your timeline, in the feed, or in
        public collections — but stay in your private collections. Use a card&apos;s
        menu to unhide.
      </p>

      {error ? (
        <p className="text-sm text-destructive">{error}</p>
      ) : loading ? (
        <p className="text-sm text-muted-foreground">Loading…</p>
      ) : feed.length === 0 ? (
        <p className="text-sm text-muted-foreground">No hidden posts.</p>
      ) : (
        feed.map((p) => (
          <PostScrollCard
            key={p.id}
            post={p}
            onUpdated={onPostUpdated}
            onHiddenChange={onHiddenChange}
          />
        ))
      )}
    </div>
  );
}