import Link from "next/link";
import { notFound } from "next/navigation";
import { ContentCard, EmptyState } from "@/components/public/ui";
import { prisma } from "@/lib/prisma";

export const dynamic = "force-dynamic";

type ThreadRow = {
  id: number;
  openerId: number | null;
  subject: string | null;
  postsCount: number | null;
  createdAt: number | null;
  updatedAt: number | null;
  pinned: number | null;
  locked: number | null;
};

function formatTimestamp(ts: number | null | undefined): string {
  if (!ts) return "";
  return new Date(ts * 1000).toISOString().slice(0, 10);
}

export default async function GuildForumPage({
  params,
}: {
  params: Promise<{ id: string }>;
}) {
  const { id } = await params;
  const guildId = Number(id);
  if (!Number.isInteger(guildId) || guildId <= 0) notFound();

  // Guild header (read-only). A DB hiccup degrades to notFound rather than 500.
  let guild: { id: number; name: string; badge: string } | null = null;
  try {
    guild = await prisma.guilds.findUnique({
      where: { id: guildId },
      select: { id: true, name: true, badge: true },
    });
  } catch {
    guild = null;
  }

  if (!guild) notFound();

  // Threads for this guild. Pinned first, then most-recently active.
  let threads: ThreadRow[] = [];
  try {
    threads = await prisma.guildsForumsThreads.findMany({
      where: { guildId: guild.id, state: 0 },
      orderBy: [{ pinned: "desc" }, { updatedAt: "desc" }, { id: "desc" }],
      take: 100,
      select: {
        id: true,
        openerId: true,
        subject: true,
        postsCount: true,
        createdAt: true,
        updatedAt: true,
        pinned: true,
        locked: true,
      },
    });
  } catch {
    threads = [];
  }

  // Resolve opener usernames in one query (no relation exists in the schema, so
  // join the users table manually by id). Falls back to the raw author id.
  const openerIds = Array.from(
    new Set(
      threads
        .map((t) => t.openerId ?? 0)
        .filter((v) => v > 0),
    ),
  );

  let users: { id: number; username: string }[] = [];
  try {
    users = openerIds.length
      ? await prisma.user.findMany({
          where: { id: { in: openerIds } },
          select: { id: true, username: true },
        })
      : [];
  } catch {
    users = [];
  }

  const usernameById = new Map(users.map((u) => [u.id, u.username]));

  return (
    <main style={{ display: "grid", gap: "1.5rem" }}>
      <p style={{ margin: 0 }}>
        <Link href={`/guilds/${guild.id}`}>← Back to guild</Link>
      </p>

      <ContentCard
        icon="🗣️"
        title={`${guild.name || "Unnamed guild"} — Forum`}
        subtitle={`${threads.length} ${threads.length === 1 ? "thread" : "threads"}`}
        action={
          <Link href={`/guilds/${guild.id}/forum/new`} className="btn btn-primary">
            + New thread
          </Link>
        }
      />

      <ContentCard padded={threads.length === 0}>
        {threads.length === 0 ? (
          <EmptyState icon="🗣️">No threads in this forum yet.</EmptyState>
        ) : (
          <table>
            <thead>
              <tr>
                <th style={{ padding: "0.6rem 0.75rem" }}>Subject</th>
                <th style={{ padding: "0.6rem 0.75rem" }}>Author</th>
                <th style={{ padding: "0.6rem 0.75rem" }}>Posts</th>
                <th style={{ padding: "0.6rem 0.75rem" }}>Date</th>
              </tr>
            </thead>
            <tbody>
              {threads.map((t) => {
                const opener = t.openerId ?? 0;
                const username = opener > 0 ? usernameById.get(opener) : undefined;
                return (
                  <tr key={t.id}>
                    <td style={{ padding: "0.6rem 0.75rem" }}>
                      <span style={{ fontWeight: 700 }}>
                        {t.subject?.trim() || "(no subject)"}
                      </span>
                      {t.pinned ? (
                        <span className="online-badge online" style={{ marginLeft: "0.5rem" }}>
                          📌 Pinned
                        </span>
                      ) : null}
                      {t.locked ? (
                        <span className="online-badge" style={{ marginLeft: "0.5rem" }}>
                          🔒 Locked
                        </span>
                      ) : null}
                    </td>
                    <td style={{ padding: "0.6rem 0.75rem" }}>
                      {username ? (
                        <Link href={`/u/${username}`}>{username}</Link>
                      ) : (
                        <span className="muted">
                          {opener > 0 ? `User #${opener}` : "Unknown"}
                        </span>
                      )}
                    </td>
                    <td style={{ padding: "0.6rem 0.75rem" }}>
                      {t.postsCount ?? 0}
                    </td>
                    <td className="muted" style={{ padding: "0.6rem 0.75rem" }}>
                      {formatTimestamp(t.createdAt)}
                    </td>
                  </tr>
                );
              })}
            </tbody>
          </table>
        )}
      </ContentCard>
    </main>
  );
}