import type { LiveMatch } from './tournament';
import type { MatchStatus, Stage } from '../../src/lib/types';

// football-data.org v4 — the reliable (if delayed) free source.
// Free tier: World Cup is included, 10 req/min. We poll one endpoint (~1 req/min).
const BASE = 'https://api.football-data.org/v4';
const COMPETITION = 'WC';

interface FdTeam { name: string | null }
interface FdScore { home: number | null; away: number | null }
interface FdMatch {
  status: string;
  stage: string;
  group: string | null;
  utcDate: string;
  minute?: number | null;
  homeTeam: FdTeam;
  awayTeam: FdTeam;
  score: { fullTime: FdScore };
}

function mapStatus(s: string): MatchStatus | null {
  switch (s) {
    case 'SCHEDULED':
    case 'TIMED':
      return 'scheduled';
    case 'IN_PLAY':
    case 'PAUSED':
      return 'live';
    case 'FINISHED':
      return 'finished';
    default:
      return null; // POSTPONED / SUSPENDED / CANCELLED — ignore
  }
}

function mapStage(s: string): Stage | null {
  switch (s) {
    case 'GROUP_STAGE':
      return 'group';
    case 'LAST_32':
      return 'r32';
    case 'LAST_16':
      return 'r16';
    case 'QUARTER_FINALS':
      return 'qf';
    case 'SEMI_FINALS':
      return 'sf';
    case 'THIRD_PLACE':
      return 'third';
    case 'FINAL':
      return 'final';
    default:
      return null;
  }
}

export async function fetchFootballData(token: string): Promise<LiveMatch[]> {
  const res = await fetch(`${BASE}/competitions/${COMPETITION}/matches`, {
    headers: { 'X-Auth-Token': token },
    signal: AbortSignal.timeout(12_000),
  });
  if (!res.ok) throw new Error(`football-data ${res.status}`);
  const body = (await res.json()) as { matches?: FdMatch[] };
  const out: LiveMatch[] = [];
  for (const m of body.matches ?? []) {
    const status = mapStatus(m.status);
    const stage = mapStage(m.stage);
    if (!status || !stage || !m.homeTeam.name || !m.awayTeam.name) continue;
    out.push({
      home: m.homeTeam.name,
      away: m.awayTeam.name,
      group: m.group ? m.group.replace('GROUP_', '') : null,
      stage,
      kickoff: m.utcDate,
      homeScore: m.score.fullTime.home,
      awayScore: m.score.fullTime.away,
      status,
      minute: m.minute ?? null,
    });
  }
  return out;
}