/// Defaults for 4-hour slot market history ([MarketHistoryFourHourSlot]).
/// Env overrides via [MarketHistoryEnv] in [ServerEnv.load].
abstract final class MarketHistoryConfig {
  /// Rolling window length in calendar days (UTC).
  static const int windowDays = 7;

  /// Alpaca bar aggregation for market-history backfill (six slots per UTC day).
  static const String barTimeframe = '4Hour';

  /// Width of each history slot in hours (`24 / slotsPerDay`).
  static const int slotHours = 4;

  /// Symbols per Alpaca `GET /v2/stocks/bars` request (max ~100).
  static const int historySyncBatchSize = 100;

  /// Hard cap on symbols synced per run (Alpaca Basic rate-limit safety).
  static const int historySyncMaxSymbols = 2000;

  /// Minimum 4-hour bars required before a symbol is eligible for the
  /// guess-the-move question rule.
  static const int minBarsForGuess = 5;

  /// Hours before the same symbol can fire another guess question.
  static const int guessCooldownHours = 24;

  /// Rows deleted per cleanup loop iteration (Postgres batched DELETE).
  static const int retentionBatchSize = 5000;

  /// Max Alpaca HTTP calls per rolling minute during history backfill.
  static const int apiRequestsPerMinute = 200;

  /// Wait after HTTP 429 before retrying the same bars request.
  static const Duration rateLimitCooldown = Duration(minutes: 1);
}