import { data, Link, useLoaderData } from "react-router";
import type { LoaderFunctionArgs } from "react-router";
import {
  getBandById,
  getBandLinks,
  getBandMembers,
  getBandRevisions,
  type BandMemberRow,
} from "~/lib/db.server";
import { LINK_TYPE_LABEL } from "~/lib/constants";

export async function loader({ params }: LoaderFunctionArgs) {
  const band = getBandById(params.uuid!);
  if (!band) throw data("Not found", { status: 404 });
  const links = getBandLinks(band.id);
  const members = getBandMembers(band.id);
  const revisions = getBandRevisions(band.id);
  return { band, links, members, latest: revisions[0] ?? null };
}

const STATUS_LABEL: Record<string, string> = {
  active: "活動中",
  hiatus: "活動休止",
  disbanded: "解散",
};

function periodLabel(m: BandMemberRow): string | null {
  if (!m.since && !m.until) return null;
  const from = m.since || "?";
  const to = m.until || "現在";
  return `${from} 〜 ${to}`;
}

export default function BandDetail() {
  const { band, links, members, latest } = useLoaderData<typeof loader>();

  // group members by artist_id for display
  const artistIds = [...new Set(members.map((m) => m.artist_id))];

  return (
    <main>
      <div className="detail-header">
        <div className="detail-info">
          <h1>{band.name}</h1>
          <div className="detail-subtitle">
            {band.area && <span>{band.area}</span>}
            <span>{STATUS_LABEL[band.status] ?? band.status}</span>
          </div>
          {band.description && (
            <p className="detail-desc">{band.description}</p>
          )}
        </div>
        <div className="detail-actions">
          <Link to={`/bands/of/${band.id}/history`} className="history">履歴</Link>
          <Link to={`/bands/of/${band.id}/edit`} className="edit">編集</Link>
        </div>
      </div>

      {artistIds.length > 0 && (
        <section>
          <h2>メンバー</h2>
          <ul className="member-list">
            {artistIds.map((artistId) => {
              const group = members.filter((m) => m.artist_id === artistId);
              const first = group[0];
              return (
                <li key={artistId}>
                  <div className="member-main">
                    <Link to={`/artists/of/${artistId}`}>{first.artist_name}</Link>
                    {group.flatMap((m) =>
                      m.role ? m.role.split(", ").filter(Boolean).map((r, i) => (
                        <span key={`${m.id}-${i}`} className="badge">{r}</span>
                      )) : []
                    ).filter((_, i, arr) => {
                      // deduplicate role badges across periods (keep unique labels)
                      return true;
                    })}
                  </div>
                  {group.some((m) => m.since || m.until || m.note) && (
                    <ul className="period-list">
                      {group.map((m) => {
                        const label = periodLabel(m);
                        if (!label && !m.note) return null;
                        return (
                          <li key={m.id} className="period-item">
                            {label && <span className="period-range">{label}</span>}
                            {m.note && <span className="period-note">{m.note}</span>}
                          </li>
                        );
                      })}
                    </ul>
                  )}
                </li>
              );
            })}
          </ul>
        </section>
      )}

      {links.length > 0 && (
        <section>
          <h2>リンク</h2>
          <ul className="link-list">
            {links.map((l) => (
              <li key={l.id}>
                <a href={l.url} target="_blank" rel="noopener noreferrer">
                  {LINK_TYPE_LABEL[l.label] ?? l.label}
                </a>
              </li>
            ))}
          </ul>
        </section>
      )}

      <hr />
      <div className="meta">
        <p>/bands/of/{band.id}</p>
        <p>
          <Link to={`/bands/named/${band.slug}`}>/bands/named/{band.slug}</Link>
        </p>
        {latest && (
          <p className="updated">最終更新: {latest.created_at} — {latest.message}</p>
        )}
      </div>
    </main>
  );
}
