import type { MatchFullStat } from '../../../src/lib/types';

// Pure normalizer for the FotMob matchDetails `stats` payload — no network or
// DB, unit-testable in isolation (same pattern as statsNormalize).

/** Curated full-time stats, in display order: FotMob key → our i18n key.
 *  Unknown keys are dropped so the client's label dict stays exhaustive. */
const FULL_STAT_KEYS: [string, string][] = [
  ['expected_goals', 'xg'],
  ['expected_goals_on_target', 'xgot'],
  ['big_chance', 'bigChances'],
  ['accurate_passes', 'accuratePasses'],
  ['long_balls_accurate', 'longBalls'],
  ['accurate_crosses', 'crosses'],
  ['touches_opp_box', 'touchesInBox'],
  ['corners', 'corners'],
  ['Offsides', 'offsides'],
  ['fouls', 'fouls'],
  ['matchstats.headers.tackles', 'tackles'],
  ['interceptions', 'interceptions'],
  ['shot_blocks', 'blocks'],
  ['clearances', 'clearances'],
  ['keeper_saves', 'saves'],
  ['duel_won', 'duelsWon'],
  ['ground_duels_won', 'groundDuels'],
  ['aerials_won', 'aerialDuels'],
  ['dribbles_succeeded', 'dribbles'],
];

interface RawStatEntry { key?: string; stats?: unknown[]; type?: string }
interface RawStatGroup { stats?: RawStatEntry[] }
/** matchDetails `stats`: Periods.{All,FirstHalf,SecondHalf}.stats = groups. */
export interface RawMatchStats { Periods?: { All?: { stats?: RawStatGroup[] } } }

const usable = (v: unknown): v is string | number =>
  (typeof v === 'number' && Number.isFinite(v)) || (typeof v === 'string' && v.trim() !== '');

/** Full-match stat rows from a raw FotMob `stats` payload. Any shape
 *  surprise degrades to fewer rows (or none) — never a throw. */
export function normalizeMatchStats(raw: unknown): MatchFullStat[] {
  const groups = (raw as RawMatchStats | null | undefined)?.Periods?.All?.stats;
  if (!Array.isArray(groups)) return [];
  // Categories repeat across groups ("Top stats" previews the rest) — first
  // occurrence wins, output follows the whitelist order.
  const seen = new Map<string, { home: string; away: string }>();
  for (const g of groups) {
    if (!g || !Array.isArray(g.stats)) continue;
    for (const s of g.stats) {
      if (!s || typeof s.key !== 'string' || s.type === 'title' || !Array.isArray(s.stats)) continue;
      const [h, a] = s.stats;
      if (!usable(h) || !usable(a) || seen.has(s.key)) continue;
      seen.set(s.key, { home: String(h), away: String(a) });
    }
  }
  const out: MatchFullStat[] = [];
  for (const [fmKey, key] of FULL_STAT_KEYS) {
    const v = seen.get(fmKey);
    if (v) out.push({ key, ...v });
  }
  return out;
}