"use client";

/**
 * /u/me — owner Posts grid (the default tab).
 *
 * Grid-only — no Grid/Scroll toggle. Tapping a thumbnail jumps to
 * /u/me/posts#post-<id> where the Instagram-style scroll feed renders
 * the full passages.
 *
 * `?edit=1` (set by the header's Edit profile button) swaps the grid
 * for the inline edit form. Saving returns to /u/me. Keeps the URL
 * shareable while avoiding a separate route + layout.
 */

import { Suspense, useEffect, useState } from "react";
import { useRouter, useSearchParams } from "next/navigation";
import { LayoutGrid } from "lucide-react";
import { useAuth } from "@/components/auth/auth-provider";
import { ProfileEditForm } from "@/components/profile/profile-edit-form";
import { PostGridCard } from "@/components/social/post-grid-card";
import { ConfirmModal } from "@/components/ui/confirm-modal";
import { posts, SocialError, type Post } from "@/lib/social";

export default function MyProfilePage() {
  // useSearchParams() forces a CSR bailout during prerender; the
  // Suspense boundary is required by Next.js so the build doesn't fail
  // (the same wrapping is in app/u/me/layout.tsx for its own check).
  // The fallback matches the page's idle loading state so the brief
  // moment before search params resolve doesn't flash an empty section.
  return (
    <Suspense
      fallback={<p className="text-sm text-muted-foreground">Loading…</p>}
    >
      <MyProfilePageInner />
    </Suspense>
  );
}

function MyProfilePageInner() {
  const { user } = useAuth();
  const router = useRouter();
  const searchParams = useSearchParams();
  const editMode = searchParams.get("edit") === "1";

  const [feed, setFeed] = useState<Post[]>([]);
  const [loading, setLoading] = useState(true);
  const [error, setError] = useState<string | null>(null);
  // Post id pending confirmation — modal opens when non-null and runs
  // the actual delete on confirm.
  const [pendingDelete, setPendingDelete] = useState<string | null>(null);

  useEffect(() => {
    if (!user) return;
    posts
      .mine()
      .then((rows) => setFeed(rows ?? []))
      .catch((err) =>
        setError(
          err instanceof SocialError ? err.message : "Could not load posts.",
        ),
      )
      .finally(() => setLoading(false));
  }, [user]);

  // Card delete buttons stage an id; ConfirmModal runs `performDelete`
  // when the user confirms. We throw on failure so the modal stays open
  // with an inline error message.
  async function performDelete() {
    const id = pendingDelete;
    if (!id) return;
    const prev = feed;
    setFeed((rows) => rows.filter((p) => p.id !== id));
    try {
      await posts.delete(id);
    } catch (err) {
      setFeed(prev);
      const msg =
        err instanceof SocialError ? err.message : "Could not delete.";
      setError(msg);
      throw new Error(msg);
    }
  }

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

  if (!user) return null;

  if (editMode) {
    return <ProfileEditForm user={user} onDone={() => router.replace("/u/me")} />;
  }

  return (
    <section>
      {error ? (
        <p className="text-sm text-destructive">{error}</p>
      ) : loading ? (
        <p className="text-sm text-muted-foreground">Loading…</p>
      ) : feed.length === 0 ? (
        <EmptyPosts />
      ) : (
        <div className="grid grid-cols-2 gap-2 sm:gap-3">
          {feed.map((p) => (
            <PostGridCard
              key={p.id}
              post={p}
              onDelete={(id) => setPendingDelete(id)}
              onUpdated={onPostUpdated}
              href={`/u/me/posts#post-${p.id}`}
            />
          ))}
        </div>
      )}

      <ConfirmModal
        open={!!pendingDelete}
        onClose={() => setPendingDelete(null)}
        title="Delete this post?"
        message="The post will be removed permanently from your feed and from any collections it's in. This can't be undone."
        confirmLabel="Delete post"
        onConfirm={performDelete}
      />
    </section>
  );
}

function EmptyPosts() {
  return (
    <div className="flex flex-col items-center text-center gap-3 py-12 text-muted-foreground">
      <LayoutGrid className="size-8" />
      <p className="text-sm">
        You haven&apos;t posted anything yet. Select any passage in the
        knowledgebase and use the toolbar to share it to your feed.
      </p>
    </div>
  );
}