/// Market-history pipeline settings loaded from env (§7).
class MarketHistoryEnv {
  MarketHistoryEnv({
    required this.syncEnabled,
    required this.windowDays,
    required this.retentionDays,
    required this.archiveEnabled,
    required this.universeRefreshHours,
    required this.historySyncHours,
    required this.cleanupHours,
    required this.syncHourUtc,
    required this.historySyncBatchSize,
    required this.historySyncMaxSymbols,
    required this.minBarsForGuess,
    required this.guessCooldownHours,
    required this.apiRequestsPerMinute,
    required this.staleSyncRunMinutes,
  });

  final bool syncEnabled;
  final int windowDays;
  final int retentionDays;
  final bool archiveEnabled;
  final int universeRefreshHours;
  final int historySyncHours;
  final int cleanupHours;

  /// UTC hour (0–23) for optional daily alignment, or `null` when unset.
  final int? syncHourUtc;
  final int historySyncBatchSize;
  final int historySyncMaxSymbols;
  final int minBarsForGuess;
  final int guessCooldownHours;
  final int apiRequestsPerMinute;
  final int staleSyncRunMinutes;

  static MarketHistoryEnv fromMap(Map<String, String> env) {
    final bool syncEnabled =
        (env['MARKET_HISTORY_SYNC_ENABLED'] ?? 'false').toLowerCase() == 'true';
    final int windowDays =
        _positiveInt(env['MARKET_HISTORY_WINDOW_DAYS'], defaultValue: 5, name: 'MARKET_HISTORY_WINDOW_DAYS');
    final int retentionDays = _positiveInt(
      env['MARKET_HISTORY_RETENTION_DAYS'],
      defaultValue: 5,
      name: 'MARKET_HISTORY_RETENTION_DAYS',
    );
    final bool archiveEnabled =
        (env['MARKET_HISTORY_ARCHIVE_ENABLED'] ?? 'false').toLowerCase() ==
            'true';
    final int universeRefreshHours = _positiveInt(
      env['MARKET_UNIVERSE_REFRESH_HOURS'],
      defaultValue: 24,
      name: 'MARKET_UNIVERSE_REFRESH_HOURS',
    );
    final int historySyncHours = _positiveInt(
      env['MARKET_HISTORY_SYNC_HOURS'],
      defaultValue: 24,
      name: 'MARKET_HISTORY_SYNC_HOURS',
    );
    final int cleanupHours = _positiveInt(
      env['MARKET_HISTORY_CLEANUP_HOURS'],
      defaultValue: 24,
      name: 'MARKET_HISTORY_CLEANUP_HOURS',
    );
    final int? syncHourUtc = _optionalSyncHourUtc(env['MARKET_HISTORY_SYNC_HOUR_UTC']);
    final int historySyncBatchSize = _positiveInt(
      env['HISTORY_SYNC_BATCH_SIZE'],
      defaultValue: 50,
      name: 'HISTORY_SYNC_BATCH_SIZE',
    );
    final int historySyncMaxSymbols = _positiveInt(
      env['HISTORY_SYNC_MAX_SYMBOLS'],
      defaultValue: 2000,
      name: 'HISTORY_SYNC_MAX_SYMBOLS',
    );
    final int minBarsForGuess = _positiveInt(
      env['MIN_BARS_FOR_GUESS'],
      defaultValue: 5,
      name: 'MIN_BARS_FOR_GUESS',
    );
    final int guessCooldownHours = _positiveInt(
      env['GUESS_COOLDOWN_HOURS'],
      defaultValue: 24,
      name: 'GUESS_COOLDOWN_HOURS',
    );
    final int apiRequestsPerMinute = _positiveInt(
      env['MARKET_HISTORY_API_REQUESTS_PER_MINUTE'],
      defaultValue: 200,
      name: 'MARKET_HISTORY_API_REQUESTS_PER_MINUTE',
    );
    final int staleSyncRunMinutes = _positiveInt(
      env['MARKET_HISTORY_SYNC_STALE_MINUTES'],
      defaultValue: 30,
      name: 'MARKET_HISTORY_SYNC_STALE_MINUTES',
    );

    return MarketHistoryEnv(
      syncEnabled: syncEnabled,
      windowDays: windowDays,
      retentionDays: retentionDays,
      archiveEnabled: archiveEnabled,
      universeRefreshHours: universeRefreshHours,
      historySyncHours: historySyncHours,
      cleanupHours: cleanupHours,
      syncHourUtc: syncHourUtc,
      historySyncBatchSize: historySyncBatchSize,
      historySyncMaxSymbols: historySyncMaxSymbols,
      minBarsForGuess: minBarsForGuess,
      guessCooldownHours: guessCooldownHours,
      apiRequestsPerMinute: apiRequestsPerMinute,
      staleSyncRunMinutes: staleSyncRunMinutes,
    );
  }

  /// Fails fast when market-history flags conflict with trading gates.
  void assertConsistent({required bool tradingEnabled}) {
    if (syncEnabled && !tradingEnabled) {
      throw StateError(
        'MARKET_HISTORY_SYNC_ENABLED=true requires TRADING_ENABLED=true',
      );
    }
  }

  static int _positiveInt(
    String? raw, {
    required int defaultValue,
    required String name,
  }) {
    if (raw == null || raw.trim().isEmpty) {
      return defaultValue;
    }
    final int? parsed = int.tryParse(raw.trim());
    if (parsed == null || parsed <= 0) {
      throw ArgumentError.value(raw, name, 'must be a positive integer');
    }
    return parsed;
  }

  static int? _optionalSyncHourUtc(String? raw) {
    if (raw == null || raw.trim().isEmpty) {
      return null;
    }
    final int? parsed = int.tryParse(raw.trim());
    if (parsed == null || parsed < 0 || parsed > 23) {
      throw ArgumentError.value(
        raw,
        'MARKET_HISTORY_SYNC_HOUR_UTC',
        'must be an integer from 0 to 23',
      );
    }
    return parsed;
  }
}