import { useEffect, useState } from 'react';
import { Link, useNavigate } from 'react-router-dom';
import { api } from '../lib/api.js';
import { FORMAT_LABEL, serverLabel, timeAgo } from '../lib/labels.js';
import { getAccess } from '../lib/session.js';
import { useOverview } from '../lib/useMatch.js';
import MapImage from '../components/MapImage.jsx';

const GROUPS = [
  { key: 'open', title: 'Offen', empty: 'Keine offenen Lobbys. Erstelle ein Match, um zu starten.' },
  { key: 'running', title: 'Laufend', empty: 'Gerade läuft kein Match.' },
  { key: 'closed', title: 'Abgeschlossen', empty: 'Noch keine abgeschlossenen Matches.' },
];

export default function Overview() {
  const { matches } = useOverview();
  return (
    <div className="overview">
      <section className="overview-head">
        <div>
          <h1>Match-Lobbys</h1>
          <p className="lead">Teams treten mit ihrem Einladungscode bei, die Captains führen das Map-Veto, der Server wird automatisch eingerichtet.</p>
        </div>
        <CodeEntry />
      </section>

      <KnifeServers />

      {matches === null ? (
        <p className="muted">Lade Matches …</p>
      ) : (
        <div className="groups">
          {GROUPS.map((g) => {
            const list = matches.filter((m) => m.group === g.key);
            return (
              <section key={g.key} className={`group group-${g.key}`}>
                <h2>{g.title} <span className="count">{list.length}</span></h2>
                {list.length === 0 ? <p className="muted small">{g.empty}</p> : g.key === 'running' ? (
                  <div className="run-grid">
                    {list.map((m) => <RunningCard key={m.id} match={m} />)}
                  </div>
                ) : (
                  <ul className="match-list">
                    {list.map((m) => <MatchRow key={m.id} match={m} />)}
                  </ul>
                )}
              </section>
            );
          })}
        </div>
      )}
    </div>
  );
}

function MatchRow({ match: m }) {
  const access = getAccess(m.id);
  const server = serverLabel(m.server);
  return (
    <li>
      <Link to={`/m/${m.id}`} className="match-row">
        <div className="match-row-teams">
          <span className="team-a">{m.teamA}</span>
          {m.seriesScore && m.format !== 'bo1' ? (
            <span className="row-score" title="Serienstand">{m.seriesScore.A}:{m.seriesScore.B}</span>
          ) : (
            <span className="vs">vs.</span>
          )}
          <span className="team-b">{m.teamB}</span>
        </div>
        <div className="match-row-meta">
          {m.currentMap && (
            <span className={m.currentMap.finished ? '' : 'row-live'}>
              {m.currentMap.finished ? '' : <span className="live-badge">Live</span>} {m.currentMap.name} {m.currentMap.score.A}:{m.currentMap.score.B}
            </span>
          )}
          <span>{m.modeLabel}</span>
          <span>{FORMAT_LABEL[m.format]}</span>
          {m.group === 'open' && <span>{m.players.A + m.players.B}/{m.players.teamSize * 2} Spieler</span>}
          <span className={`tone-${server.tone}`}>{m.statusLabel}</span>
          {access && <span className="mine">Dein Zugang</span>}
          <span className="muted">{timeAgo(m.createdAt)}</span>
        </div>
      </Link>
    </li>
  );
}

/** Karte für ein laufendes Match: Map als Hintergrund, Stand groß, Serie und Status darunter. */
function RunningCard({ match: m }) {
  const server = serverLabel(m.server);
  const map = m.currentMap;
  const live = map && !map.finished;
  const bo1 = m.format === 'bo1';
  return (
    <Link to={`/m/${m.id}`} className={`run-card ${live ? 'is-live' : ''}`} style={{ '--map': map?.color ?? '#3a4150' }}>
      {map?.image && <MapImage map={{ image: map.image, color: map.color, name: map.name }} className="run-art" />}
      <div className="run-top">
        <span className="run-mode">{m.modeLabel}, {FORMAT_LABEL[m.format]}</span>
        {live ? <span className="live-badge run-live">Live</span> : <span className={`run-status tone-${server.tone}`}>{m.statusLabel}</span>}
      </div>
      <div className="run-teams">
        <span className="run-team a">{m.teamA}</span>
        <span className="run-score">
          {map ? <>{map.score.A}<i>:</i>{map.score.B}</> : <i className="run-vs">vs.</i>}
        </span>
        <span className="run-team b">{m.teamB}</span>
      </div>
      <div className="run-foot">
        <span>{map ? `Map ${map.number}: ${map.name}` : 'Veto läuft'}</span>
        {!bo1 && m.seriesScore && <span className="run-series">Serie {m.seriesScore.A}:{m.seriesScore.B}</span>}
      </div>
    </Link>
  );
}

function CodeEntry() {
  const [code, setCode] = useState('');
  const [error, setError] = useState(null);
  const navigate = useNavigate();
  const submit = async (e) => {
    e.preventDefault();
    setError(null);
    try {
      const res = await api('/access', { method: 'POST', body: { code } });
      navigate(res.access === 'spectator' ? `/watch/${code.trim()}` : `/join/${code.trim()}`);
    } catch (err) {
      setError(err.message);
    }
  };
  return (
    <form className="code-entry" onSubmit={submit}>
      <label htmlFor="code">Einladungs- oder Zuschauercode</label>
      <div className="row">
        <input id="code" value={code} onChange={(e) => setCode(e.target.value)} placeholder="ABCD-EFGH" autoComplete="off" spellCheck="false" />
        <button className="btn" disabled={code.replace(/[^a-z0-9]/gi, '').length < 8}>Beitreten</button>
      </div>
      {error && <p className="field-error">{error}</p>}
    </form>
  );
}
/** Offene Messer-Server für die Seitenwahl, zum direkten Verbinden. */
function KnifeServers() {
  const [servers, setServers] = useState([]);
  useEffect(() => {
    let alive = true;
    const load = () => api('/knife-servers').then((res) => alive && setServers(res.servers)).catch(() => {});
    load();
    const t = setInterval(load, 10_000);
    return () => {
      alive = false;
      clearInterval(t);
    };
  }, []);
  if (servers.length === 0) return null;
  return (
    <section className="group knife-public">
      <h2>Messer-Server für die Seitenwahl <span className="count">{servers.length}</span></h2>
      <p className="muted small">Ohne Passwort, auch im LAN-Reiter von Steam. Nach eurer Messerrunde setzt sich der Server selbst zurück.</p>
      <ul className="knife-list">
        {servers.map((k) => (
          <li key={k.id}>
            <strong>{k.name}</strong>
            {k.modeShort && <span className="knife-mode">{k.modeShort}</span>}
            <span className="muted small">{k.mapName}</span>
            <span className="small">{k.playerCount ? `${k.playerCount} Spieler` : 'frei'}</span>
            <code>{k.connect}</code>
            <a className="btn btn-sm" href={k.steamUrl}>Verbinden</a>
          </li>
        ))}
      </ul>
    </section>
  );
}