import 'package:postgres/postgres.dart';

import '../alpaca/alpaca_assets_client.dart';
import '../alpaca/alpaca_models.dart';
import 'sync_run_recorder.dart';
import 'tradable_assets_db.dart';

/// Outcome of a single [TradableAssetsSync.runOnce] invocation.
///
/// On the happy path [error] is `null` and [rowsWritten] is the number of
/// asset rows upserted. On a failure path [error] holds the upstream
/// message and [rowsWritten] is `0` — the exception itself is never
/// rethrown to callers (the scheduler in §5 must keep going).
class TradableAssetsSyncResult {
  TradableAssetsSyncResult({
    required this.rowsWritten,
    required this.startedAt,
    required this.finishedAt,
    this.error,
  });

  final int rowsWritten;
  final DateTime startedAt;
  final DateTime finishedAt;
  final String? error;

  bool get succeeded => error == null;
}

/// Daily refresh of the `tradable_assets` cache from Alpaca.
///
/// One pass:
/// 1. [SyncRunRecorder] inserts a `market_data_sync_runs` row with
///    `kind='universe'`.
/// 2. Pull `/v2/assets?status=active&asset_class=us_equity`.
/// 3. Upsert into `tradable_assets`, marking missing symbols inactive.
/// 4. Recorder closes the row with `finished_at` + `rows_written` (or
///    `error` on failure).
///
/// The scheduler in §5 runs this once per `MARKET_UNIVERSE_REFRESH_HOURS`.
class TradableAssetsSync {
  TradableAssetsSync({
    required AlpacaAssetsClient assetsClient,
    required TradableAssetsDb assetsDb,
    required Connection connection,
  })  : _assetsClient = assetsClient,
        _assetsDb = assetsDb,
        _recorder = SyncRunRecorder(connection);

  final AlpacaAssetsClient _assetsClient;
  final TradableAssetsDb _assetsDb;
  final SyncRunRecorder _recorder;

  static const String kind = 'universe';

  Future<TradableAssetsSyncResult> runOnce({DateTime? now}) async {
    final DateTime started = (now ?? DateTime.now()).toUtc();

    final SyncRunOutcome outcome = await _recorder.record(
      kind,
      () async {
        final List<AlpacaAsset> assets =
            await _assetsClient.listActiveTradable();
        await _assetsDb.upsertAll(assets, now: started);
        return SyncRunCounts(rowsWritten: assets.length);
      },
      now: started,
    );

    return TradableAssetsSyncResult(
      rowsWritten: outcome.rowsWritten,
      startedAt: outcome.startedAt,
      finishedAt: outcome.finishedAt,
      error: outcome.error,
    );
  }
}